Introduction

Shoulder Dysfunction

Palpation

Capsule and Ligaments

Bursae

Nerves

Joint Actions

Arthrokinematics

Integrated Function

Movement Impairment (Postural Dysfunction)

Shoulder Joint Anatomy (Glenohumeral Joint)

REPS

NYPT

ACSM

AFAA

REPSI

AOTA

YOGA

AUSPHYSIO

TPTA

PACE

WITS

CIMSPA

NASM

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Shoulder (Glenohumeral) Joint

This course describes shoulder joint anatomy, which includes the glenohumeral joint. This includes descriptions of the bones, synovial joints, joint actions, ligaments, bursae, relative location, the relationship between the bones of the shoulder/humerus, and the muscles that cross them. Further, this course discusses palpation and introduces shoulder joint <a id="specificity" data-tip="1224" target="_blank" href="/glossary-term/specificity" class="glossary">specific</a> exercises, manual techniques, and interventions for dysfunction, pain, <a id="posture" data-tip="1658" target="_blank" href="/glossary-term/posture" class="glossary">posture</a>, and <a id="movement-impairment" data-tip="1575" target="_blank" href="/glossary-term/movement-impairment" class="glossary">movement impairment</a>. The shoulder joint is included in the common compensation patterns known as rounded shoulder <a id="posture" data-tip="1658" target="_blank" href="/glossary-term/posture" class="glossary">posture</a> (RSP), upper-crossed syndrome (UCS), shoulder <a id="medial" data-tip="1568" target="_blank" href="/glossary-term/medial" class="glossary">medial</a> rotation syndrome (SMRS), and upper body dysfunction (UBD). Sports medicine professionals (personal trainers, fitness instructors, physical therapists, massage therapists, chiropractors, occupational therapists, athletic trainers, etc.) with advanced knowledge of the glenohumeral joint will improve their ability to analyze human movement and develop sophisticated exercise programs and therapeutic (rehabilitation) interventions. Further, this course is essential knowledge for future courses discussing injury prevention and physical rehabilitation/physical therapy (e.g. impingement syndrome, rotator cuff injury, scapula (shoulder blade) dysfunction, shoulder arthritis, shoulder replacement, forward head <a id="posture" data-tip="1658" target="_blank" href="/glossary-term/posture" class="glossary">posture</a>, thoracic kyphosis, sternocostal pain, and <a id="medial" data-tip="1568" target="_blank" href="/glossary-term/medial" class="glossary">medial</a> epicondylitis of the elbow), the effect the shoulder joint has on upper extremity alignment (e.g. excessive shoulder internal rotation), and shoulder joint <a id="specificity" data-tip="1224" target="_blank" href="/glossary-term/specificity" class="glossary">specific</a> techniques for enhancing sports performance (e.g. upper body (upper limb) <a id="stability" data-tip="1191" target="_blank" href="/glossary-term/stability" class="glossary">stability</a>, strength, hypertrophy, agility, and <a id="power" data-tip="1399" target="_blank" href="/glossary-term/power" class="glossary">power</a>).
<h4>Brookbush Institute&#x2019;s most recommended techniques for the Shoulder Joint (see videos below):</h4>
<ul>
 <li>Assess:
 <ul>
 <li>Overhead Squat Assessment: <a href="https://brookbushinstitute.com/video/overhead-squat-assessment-10-arms-fall">Arms Fall</a></li>
 <li>Goniometry: <a href="https://brookbushinstitute.com/courses/upper-body-goniometry">Shoulder Internal Rotation</a></li>
 <li>Goniometry: <a href="https://brookbushinstitute.com/courses/upper-body-goniometry">Shoulder External Rotation</a></li>
 </ul>
 <a href="https://brookbushinstitute.com/video/overhead-squat-assessment-10-arms-fall"> </a>
 </li>
 <li>Self-administered Techniques:
 <ul>
 <li>Release: <a href="https://brookbushinstitute.com/video/latissimus-dorsi-rhomboids-teres-major-and-posterior-deltoid-vibration-release">Latissimus Dorsi, Rhomboids, Teres Major, and </a><a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> Deltoid Vibration Release</li>
 <li>Joint Mobilization: <a href="https://brookbushinstitute.com/courses/joint-mobilizations-upper-body-self-administered">Self-administered Shoulder Mobilization</a></li>
 <li>Stretch: <a href="https://brookbushinstitute.com/video/latissimus-dorsi-and-erector-spinae-static-stretch-childs-pose">Latissimus Dorsi and Erector Spinae Static Stretch: Child&apos;s Pose</a></li>
 <li>Activation: <a href="https://brookbushinstitute.com/video/shoulder-external-rotator-isolated-activation">Shoulder External Rotator Isolated Activation</a></li>
 </ul>
 <a href="https://brookbushinstitute.com/video/shoulder-external-rotator-isolated-activation"> </a>
 </li>
 <li>Manual Techniques:
 <ul>
 <li>Mobilization: <a href="https://brookbushinstitute.com/video/anterior-posterior-shoulder-glenohumeral-joint-manual-mobilization">Shoulder (Glenohumeral) Joint </a><a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> to <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> Mobilization</li>
 <li>Manipulation: <a href="https://brookbushinstitute.com/video/thoracic-spine-manipulation">Thoracic Spine Manipulation</a></li>
 </ul>
 <a href="https://brookbushinstitute.com/video/thoracic-spine-manipulation"> </a>
 </li>
</ul>
<img alt="An image of the glenohumeral joint, humerus, and scapula" title="The shoulder joint with the ligaments, bones, and joint capsule labeled" src="https://www.datocms-assets.com/25800/1642702065-shoulder-capsule.jpg">

Course Description: Shoulder (Glenohumeral) Joint

<h2>What&apos;s in a name</h2>
<ul>
 <li><a href="http://www.etymonline.com/index.php?allowed_in_frame=0&amp;search=shoulder" target="_blank" rel="noopener noreferrer">shoulder (n)</a>: &quot;Old English sculdor &quot;shoulder,&quot; from West Germanic *skuldro (source also of Middle Dutch scouder, Dutch schouder, Old Frisian skoldere, Middle Low German scholder, Old High German scultra, German Schulter), of unknown origin, perhaps related to <a class="crossreference" href="http://www.etymonline.com/index.php?term=shield&amp;allowed_in_frame=0" target="_blank" rel="noopener">shield</a> (n.). Meaning &quot;edge of the road&quot; is attested from 1933.&quot; (<a href="http://www.etymonline.com/index.php?allowed_in_frame=0&amp;search=shoulder" target="_blank" rel="noopener noreferrer">Etymology Online</a>)</li>
 <li><a href="http://www.etymonline.com/index.php?allowed_in_frame=0&amp;search=glen" target="_blank" rel="noopener noreferrer">glene (n)</a>: Greek root meaning &quot;socket of joint&quot; (1).</li>
 <li><a href="http://www.etymonline.com/index.php?allowed_in_frame=0&amp;search=humeral" target="_blank" rel="noopener noreferrer">humeral (n)</a>: from the word <a href="http://www.etymonline.com/index.php?term=humerus&amp;allowed_in_frame=0" target="_blank" rel="noopener noreferrer">humerus (n)</a> &quot;1706, &quot;bone of the upper arm,&quot; originally (14c.) &quot;shoulder,&quot; from Latin humerus, a common spelling of umerus &quot;shoulder,&quot; from PIE *om(e)so- &quot;shoulder&quot; (source also of Sanskrit amsah, Greek omos, Old Norse ass, Gothic ams &quot;shoulder&quot;). Blount&apos;s &quot;Glossographia&quot; (1656) has humerous (adj.) &quot;That hath great shoulders.&quot; (<a href="http://www.etymonline.com/index.php?allowed_in_frame=0&amp;search=humeral" target="_blank" rel="noopener noreferrer">Etymology Online</a>)</li>
 <li>joint (n): &quot;c. 1300, &quot;an (anatomical) joint, a part of a body where two bones meet and move in contact with one another, the structure that holds such bones together,&quot; from Old French joint&quot;joint of the body&quot; (12c.), from Latin iunctus &quot;united, connected, associated,&quot; past participle of iungere &quot;join&quot; (see <a class="crossreference" href="http://www.etymonline.com/index.php?term=jugular&amp;allowed_in_frame=0" target="_blank" rel="noopener">jugular</a>). &quot; (<a href="http://www.etymonline.com/index.php?term=joint" target="_blank" rel="noopener noreferrer">Etymology Online</a>)</li>
</ul>
<a href="https://www.datocms-assets.com/25800/1642701916-1642106311-shoulder-joint-cross-section.png"><img src="https://www.datocms-assets.com/25800/1642701916-1642106311-shoulder-joint-cross-section.png" title="Cross section of the glenohumeral joint (shoulder) of the body" alt="The shoulder (glenohumeral) joint "></a>
Cross Section of the Glenohumeral Joint By Blausen.com staff. &quot;Blausen gallery 2014&quot;. Wikiversity Journal of Medicine. DOI:10.15347/wjm/2014.010. ISSN 20018762. - Own work, CC BY 3.0, http
<ul>
 <li>Joint Type:
 <ul>
 <li>Diarthrosis</li>
 <li>Synovial Joint
 <ul>
 <li>Ball and Socket Joint</li>
 </ul>
 </li>
 </ul>
 </li>
 <li>Bones: Humerus and Scapula
 <ul>
 <li><span style="background-color: transparent; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-ligatures: inherit; font-variant-caps: inherit; font-weight: inherit; letter-spacing: 0px;">The shoulder joint is comprised of the humerus and glenoid fossa of the scapula, hence the name glenohumeral joint (GH), and it is one of three articulations of the shoulder complex. The other two articulations are the acromioclavicular (AC) joint and sternoclavicular (SC) joint, which are commonly referenced relative to scapulothoracic motion and discussed in a separate article.</li>
 </ul>
 </li>
</ul>
<a href="https://www.datocms-assets.com/25800/1642701975-1642106387-x-ray-of-shoulder.jpeg"><img src="https://www.datocms-assets.com/25800/1642701975-1642106387-x-ray-of-shoulder.jpeg" title="An illustration and X-ray of the glenohumeral joint with boney attachments" alt="The glenohumeral joint comprised of the humerus and glenoid fossa"></a>
Illustration and X-Ray of Glenohumeral Joint - http://clinicalgate.com/wp-content/uploads/2015/03/B9780702051319000079_f007-025-9780702051319.jpg
<h4>Articular Surfaces:</h4>
<ul>
 <li>Humeral Head (ball)<span style="background-color: transparent; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-ligatures: inherit; font-variant-caps: inherit; font-weight: inherit; letter-spacing: 0px;">: A <a id="convex" data-tip="1284" target="_blank" href="/glossary-term/convex" class="glossary">convex</a> surface that is approximately half of a full sphere facing superiomedially and slightly posteriorly. The slight <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> slant of the humeral head allows for more direct contact with the relatively small glenoid fossa of the scapula. The humeral head is lined with articular cartilage and tends to be 1.9 times larger longitudinally than the glenoid fossa.</li>
 <li>Scapular Glenoid Fossa (socket): A shallow <a id="concave" data-tip="1281" target="_blank" href="/glossary-term/concave" class="glossary">concave</a> surface angled superiorly and either anterolaterally (anteverted) or posterolaterally (retroverted); 6&#xBA;-7&#xBA; of retroversion is typical (3). The surface of the glenoid fossa is longer (<a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> to <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a>) than it is wide (<a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> to <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a>) and varies considerably in size between individuals (3). The articular cartilage of the glenoid fossa is thicker around the edges than it is in the middle, which increases the surface contact area with the much larger humeral head. The shallowness of the glenoid fossa allows for greater <a id="mobility" data-tip="1455" target="_blank" href="/glossary-term/mobility" class="glossary">mobility</a> but offers minimal <a id="stability" data-tip="1191" target="_blank" href="/glossary-term/stability" class="glossary">stability</a>. The joint capsule does not enhance the <a id="stability" data-tip="1191" target="_blank" href="/glossary-term/stability" class="glossary">stability</a> significantly as it is relatively thin with a slackened <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> portion named the axillary pouch, allowing for significant <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> translation during movement. Therefore joint <a id="stability" data-tip="1191" target="_blank" href="/glossary-term/stability" class="glossary">stability</a> is primarily accomplished via musculature, of particular importance to joint <a id="stability" data-tip="1191" target="_blank" href="/glossary-term/stability" class="glossary">stability</a> are the rotator cuff muscles (<a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a>, <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a>, <a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">infraspinatus, and teres minor</a>).
 <ul>
 <li>To increase congruence with the humeral head, the scapula rests on the thorax tilted anteriorly approximately 10&#xBA;, upwardly rotated approximately 5-10&#xBA;, and internally rotated approximately 35&#xBA;, forming the scapular plane angle.</li>
 </ul>
 </li>
</ul>
<a href="https://www.datocms-assets.com/25800/1642701837-1642106253-internal-shoulder-cadaver.jpeg"><img src="https://www.datocms-assets.com/25800/1642701837-1642106253-internal-shoulder-cadaver.jpeg" width="513" height="385" title="Dissection of the shoulder (glenohumeral joint) in a cadaver" alt="A cadaver dissection of the glenohumeral joint"></a>
<h3>Alignment:</h3>
<h4>Glenoid Fossa Inclination Angle (Frontal Plane)</h4>
<ul>
 <li>Angle formed by a line parallel to the floor of the supraspinatus fossa and a line from <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> to the <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> ridge of the glenoid fossa.</li>
 <li>Normal: Glenoid inclination was 15.7&#xB0; &#xB1; 5.1&#xB0; superiorly (15)</li>
</ul>
<h4>Glenoid Fossa Retroversion Angle (Tranverse Plane)</h4>
<ul>
 <li>Angle formed by a line parallel to the floor of the supraspinatus fossa and a line from the <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> to the <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> ridge of the glenoid fossa.</li>
 <li>Normal: Retroversion of 4.9&#xB0; &#xB1; 6.1&#xB0; (15)</li>
</ul>
<a href="https://www.datocms-assets.com/25800/1642702108-1642106558-shoulder-inclination-angle.png"><img src="https://www.datocms-assets.com/25800/1642702108-1642106558-shoulder-inclination-angle.png" title="An X-ray of the glenoid fossa showing the inclination angle in the frontal plane" alt="The inclination angle of the glenoid fossa"></a>
Glenoid Fossa Inclination Angle (Frontal Plane) on X-ray
<h4>Humeral Torsion Angle (Transverse Plane)</h4>
<ul>
 <li>
 <div data-canvas-width="387.4987500000001">Torsion is defined as a state of longitudinal twisting or spiraling of the shaft of a long bone and can be measured as the difference between the joint axis of <a id="proximal" data-tip="1564" target="_blank" href="/glossary-term/proximal" class="glossary">proximal</a> and <a id="distal" data-tip="1563" target="_blank" href="/glossary-term/distal" class="glossary">distal</a> ends of the bones. Angle formed by a line bisecting the humeral head and the medial-lateral axis through the condyles at the elbow.</div>
 </li>
 <li>
 <div data-canvas-width="387.4987500000001"><span style="background-color: transparent; font-family: inherit; font-size: inherit; font-style: inherit; font-variant-ligatures: inherit; font-variant-caps: inherit; font-weight: inherit; letter-spacing: 0px;">Normal: 30&#xBA; of retroversion (of the humeral head when compared to the axis of the elbow)</div>
 </li>
</ul>
<h4>Humeral head Inclination Angle (Frontal Plane)</h4>
<ul>
 <li>Angle formed by a line through the long axis of the humeral shaft and a line bisecting the humeral head</li>
 <li>Normal: 135&#xBA;-155&#xBA;</li>
</ul>
<a href="https://www.datocms-assets.com/25800/1642702145-1642106688-humeral-head-retroversion-angle.png"><img src="https://www.datocms-assets.com/25800/1642702145-1642106688-humeral-head-retroversion-angle.png" title="A representation of humeral torsion angle between the scapula and humerus" alt="Humeral torsion angle "></a>
Humeral Torsion Angle
s://commons.wikimedia.org/w/index.php?curid=27796970

Introduction to the Shoulder (Glenohumeral) Joint

Shoulder (Glenohumeral) Joint Palpation

<ul>
 <li>Open Pack Position: 40&#xB0; of abduction in the scapular plane</li>
 <li>Close Pack Position: Full abduction and external rotation</li>
</ul>
<img src="https://www.datocms-assets.com/25800/1643487781-1642106877-glenohumeral-ligaments-edited.png" width="355" height="393" title="The shoulder (glenohumeral) joint with boney landmarks and ligaments" alt="The glenohumeral ligaments with boney landmarks labeled">
Glenohumeral Ligaments - Henry Vandyke Carter - Henry Gray (1918) Anatomy of the Human Body (See &quot;Book&quot; section below) Bartleby.com: Gray&apos;s Anatomy, Plate 326
<table>
 <tbody>
 <tr>
 <td>
 <h3>Name</h3>
 </td>
 <td>
 <h3>Attachments</h3>
 </td>
 <td>
 <h3>Course</h3>
 </td>
 <td>
 <h3>Restricted Motions</h3>
 </td>
 </tr>
 <tr>
 <td>Fibrous Capsule</td>
 <td>
 <ul>
 <li>Scapular Attachment: Rim of the glenoid fossa</li>
 <li>Humeral Attachment: Anatomic neck, <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> to the lesser tubercle</li>
 </ul>
 </td>
 <td>Proximal to distal and circumferential</td>
 <td>Restricts the end range of all motions, although the capsule is fairly loose providing extensive mobility. The inferior portion of the capsule actually hangs loose with the arm in adduction forming the axillary pouch (1). The capsule and capsular ligaments aid in maintaining negative intra-articular pressure.</td>
 </tr>
 <tr>
 <td>Glenoid Labrum</td>
 <td>
 <ul>
 <li>Scapular Attachment: Rim of the glenoid fossa</li>
 <li>Humeral Attachment: None</li>
 </ul>
 </td>
 <td>Circumferential, increasing the depth of the glenoid fossa by 50% (3).</td>
 <td>Enhances stabilization by resisting translation and aiding in the absorption or compression forces.</td>
 </tr>
 <tr>
 <td>Superior Glenohumeral Ligament</td>
 <td>
 <ul>
 <li>Scapular Attachment: Superoanterior rim of the glenoid fossa and labrum near supraglenoid tubercle, <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> to the tendon of biceps brachii (long head)</li>
 <li>Humeral Attachment: Anatomic neck, <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> to the lesser tubercle</li>
 </ul>
 </td>
 <td>Laterally</td>
 <td>
 <ul>
 <li>In anatomic position: restricts <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> and <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> translation (3)</li>
 <li>Restricts adduction past neutral</li>
 <li>Once taut in full adduction: restricts <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a>, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a>, and <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> translation (1)</li>
 </ul>
 </td>
 </tr>
 <tr>
 <td>Middle Glenohumeral Ligament</td>
 <td>
 <ul>
 <li>Scapular Attachment: <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">Superior</a> and middle <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> rim of glenoid fossa and labrum</li>
 <li>Humeral Attachment: <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> anatomic neck <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> to the <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> glenohumeral ligament attachment</li>
 </ul>
 </td>
 <td>Lateral and oblique (from superior proximally to inferiorly distally), blending with the anterior capsule and subscapularis tendon</td>
 <td>
 <ul>
 <li>Restricts external rotation</li>
 <li>In anatomic position and up to 45&#xB0; of abduction: Restricts <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> translation of the humeral head</li>
 </ul>
 </td>
 </tr>
 <tr>
 <td>Inferior Glenohumeral Ligament Complex (IGHLC) - anterior &amp; posterior bands, connecting axillary pouch</td>
 <td>
 <ul>
 <li>Scapular Attachment: <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> rim of the glenoid fossa and glenoid labrum.</li>
 <li>Humeral Attachment: <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> and <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> aspects of the <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> anatomic neck.</li>
 </ul>
 </td>
 <td>Laterally, divides into an anterior (thickest &amp; strongest portion of the capsule (1)) and posterior band connected via the axillary pouch.</td>
 <td>
 <ul>
 <li>In abduction: IGHLC resists <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> translation</li>
 <li>Anterior Band: Resists <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> translation of humeral head during abduction and external rotation</li>
 <li>Posterior Band: Resists <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> translations of the humeral head during abduction with internal rotation.</li>
 <li>Axillary Pouch: When the arm is abducted, resists anterior/posterior and <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> translation of the humeral head</li>
 </ul>
 </td>
 </tr>
 <tr>
 <td>Coracohumeral Ligament</td>
 <td>
 <ul>
 <li>Scapular Attachment: <a id="base-of-support" data-tip="1196" target="_blank" href="/glossary-term/base-of-support" class="glossary">Base</a> and <a id="lateral" data-tip="1567" target="_blank" href="/glossary-term/lateral" class="glossary">lateral</a> border of the coracoid process</li>
 <li>Humeral Attachment (2 bands):
 <ul>
 <li>Blends with the tendon of the <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a> &amp; inserts into the <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> aspect of the greater tubercle (with <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> glenohumeral ligament)</li>
 <li>Blends with <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a> and lesser tubercle</li>
 </ul>
 </li>
 </ul>
 </td>
 <td>Lateral and oblique (from superior proximally to inferiorly distally)</td>
 <td>
 <ul>
 <li>Resists end range adduction</li>
 <li>In adduction (neutral position): <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">Inferior</a> translation of the humeral head and external rotation</li>
 <li>May prevent <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a> of the humeral head if the rotator cuff is impaired (17)</li>
 </ul>
 </td>
 </tr>
 <tr>
 <td>Coracoacromial Ligament</td>
 <td>
 <ul>
 <li><a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> margin of the acromion</li>
 <li><a id="lateral" data-tip="1567" target="_blank" href="/glossary-term/lateral" class="glossary">Lateral</a> border of the coracoid process</li>
 </ul>
 </td>
 <td>Superior/posterior/lateral (acromion) to anterior/inferior/medial coracoid process</td>
 <td>Forms the anterior portion of the &quot;roof&quot; of the glenohumeral joint.</td>
 </tr>
 </tbody>
</table>
<a href="https://brookbush.s3.us-east-2.amazonaws.com/wordpress/wp-content/uploads/2016/09/Shoulder-Capsule-Netter.jpg"><img class="size-full wp-image-85212" src="https://brookbush.s3.us-east-2.amazonaws.com/wordpress/wp-content/uploads/2016/09/Shoulder-Capsule-Netter.jpg" alt="The shoulder capsule and ligaments" width="650" height="358" title="An anterior view of the shoulder capsule with boney landmarks and ligaments labeled"></a>
Shoulder Capsule and Ligaments - Netter Atlas of Human Anatomy

Shoulder Joint Connective Tissues: Capsule and Ligaments

The bursae of the glenohumeral joint are often continuous with one another, and function to reduce friction between tendons, the humeral head, and the surrounding structures (coracoacromial arch, coracoid process, <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a> <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a>, etc.)
<ul>
 <li>Subacromial Bursa: Located <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> to the <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a> tendon and <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> to the acromion process (in the subacromial space). Functions to reduce friction during elevation of the arm as the <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a> contracts and the tendon <a id="glide" data-tip="1599" target="_blank" href="/glossary-term/glide" class="glossary">slides</a> beneath the coracoacromial arch.</li>
 <li>Subdeltoid Bursa: Located <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> to the <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a> tendon and <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> to the <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>; continuous with the subacromial bursa. Functions to reduce friction during elevation of the arm between the <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a> tendon, humeral head, and <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>.</li>
 <li>Subscapular Bursa: Extension of the glenohumeral synovial membrane, located <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> to the <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a> tendon on the <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> shoulder capsule. Functions to reduce friction between the <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a> tendon and joint capsule.</li>
 <li>Subcoracoid Bursa: Located <a class="mw-redirect" title="Anterior (anatomy)" href="https://en.wikipedia.org/wiki/Anterior_%28anatomy%29" target="_blank" rel="noopener">anterior</a> to the <a title="Subscapularis muscle" href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a>, <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> to the tendon of the short head of the biceps brachii, and <a class="mw-redirect" title="Inferior (anatomy)" href="https://en.wikipedia.org/wiki/Inferior_%28anatomy%29" target="_blank" rel="noopener">inferior</a> to the <a title="Coracoid process" href="https://en.wikipedia.org/wiki/Coracoid_process" target="_blank" rel="noopener">coracoid process</a>. Functions to reduce friction between the <a class="mw-redirect" title="Coracobrachialis" href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a>, <a class="mw-redirect" title="Subscapularis" href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a>, and short head of the biceps tendons, during shoulder motion.</li>
 <li>Supra-acromial Bursa: Located <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> to the acromion process this bursa generally does not communicate with the sub-acromial bursa (18). Likely function is to serve as a barrier between the bony <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> surface of the acromion, the skin, and external loads (for example, a backpack or purse)</li>
</ul>
<a href="https://www.datocms-assets.com/25800/1642702417-1642106954-shoulder-bursae-location.jpeg"><img src="https://www.datocms-assets.com/25800/1642702417-1642106954-shoulder-bursae-location.jpeg" title="A drawing of the subacromial-subdeltoid bursa, subscapular recess, subcoracoid bursa, coracoclavicular bursa, supra-acromial bursa and medial extension of the subacromial-subdeltoid bursa." alt="Diagram of bursae surrounding the glenohumeral joint"></a>
Diagram of normal bursae surrounding the shoulder joint: (1) subacromial-subdeltoid bursa, (2) subscapular recess, (3) subcoracoid bursa, (4) coracoclavicular bursa, (5) supra-acromial bursa and (6) <a id="medial" data-tip="1568" target="_blank" href="/glossary-term/medial" class="glossary">medial</a> extension of subacromial-subdeltoid bursa. By Zameer Hirji - Zameer Hirji, Jaspal S Hunjun, Hema N Choudur (2011). &quot;Imaging of the Bursae&quot;. Journal of Clinical Imaging Science 1 (1): 22. DOI:10.4103/2156-7514.80374. ISSN 2156-7514.Figure 1, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=25309551

Shoulder (Glenohumeral) Joint Bursae

<ul>
 <li>Sensory Innervation (1, 2, 4, 19, 20, 21): The glenohumeral joint receives sensory innervation from the suprascapular (<a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> posterior/anterior), axillary (<a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> capsule), and <a id="lateral" data-tip="1567" target="_blank" href="/glossary-term/lateral" class="glossary">lateral</a> pectoral nerves (<a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> and <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> capsule) via the C4-7 <a id="nerve-cell" data-tip="1361" target="_blank" href="/glossary-term/nerve-cell" class="glossary">nerve</a> roots.</li>
</ul>
<table class="aligncenter">
 <tbody>
 <tr>
 <td width="322">
 <h3 style="text-align: left;">Muscles Crossing the Shoulder</h3>
 </td>
 <td width="315" style="text-align: left;">
 <h3>Neural Innervation (1,2,4)</h3>
 </td>
 <td width="170" style="text-align: left;">
 <h3>Nerve Root (1,2, 4)</h3>
 </td>
 </tr>
 <tr>
 <td width="322"><a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">Supraspinatus</a></td>
 <td width="315">Suprascapular Nerve</td>
 <td width="170">C4-6</td>
 </tr>
 <tr>
 <td width="322"><a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">Infraspinatus</a></td>
 <td width="315">Suprascapular Nerve</td>
 <td width="170">C5-6, possibly C4</td>
 </tr>
 <tr>
 <td><a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">Teres Minor</a></td>
 <td>Axillary Nerve</td>
 <td>C5-6</td>
 </tr>
 <tr>
 <td><a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">Deltoid</a></td>
 <td>Axillary Nerve</td>
 <td>C5-6</td>
 </tr>
 <tr>
 <td width="322">Biceps Brachii</td>
 <td width="315">Musculocutaneous Nerve</td>
 <td width="170">C5-6</td>
 </tr>
 <tr>
 <td width="322"><a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">Subscapularis</a></td>
 <td width="315">Upper and Lower Subscapularis Nerve</td>
 <td width="170">C5-7</td>
 </tr>
 <tr>
 <td width="322"><a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">Teres Major</a></td>
 <td width="315">Lower Subscapularis Nerve</td>
 <td width="170">C5-7</td>
 </tr>
 <tr>
 <td width="322"><a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">Coracobrachialis</a></td>
 <td width="315">Musculocutaneous Nerve</td>
 <td width="170">C5-7</td>
 </tr>
 <tr>
 <td width="322"><a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">Pectoralis Major</a></td>
 <td width="315">Medial &amp; Lateral Pectoral Nerve</td>
 <td width="170">C5-T1</td>
 </tr>
 <tr>
 <td><a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">Latissimus Dorsi</a></td>
 <td>Thoracodorsal Nerve</td>
 <td>C6-8</td>
 </tr>
 <tr>
 <td width="322">Triceps Brachii (long head)</td>
 <td width="315">Radial Nerve</td>
 <td width="170">C6-T1</td>
 </tr>
 </tbody>
</table>
<a href="https://www.datocms-assets.com/25800/1642702473-1642106998-anterior-innervation-of-the-shoulder-joint-the-suprascapular-nerve-and-axillary-nerve-png.jpeg"><img src="https://www.datocms-assets.com/25800/1642702473-1642106998-anterior-innervation-of-the-shoulder-joint-the-suprascapular-nerve-and-axillary-nerve-png.jpeg" title="The axillary and suprascapular nerves which innervate the shoulder joint" alt="Primary nerves which innervate the shoulder"></a>
<a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> Innervation of the Shoulder Joint - Primary nerves innervating the capsule are axillary and suprascapular.

Shoulder (Glenohumeral) Joint Nerves

<h3>Open Chain Kinematics: Humerus on Scapula</h3>
<ul>
 <li>Flexion
 <ul>
 <li>Flexors: <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid,</a> <a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a>, biceps brachii, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a> (clavicular head)</li>
 <li>Limited by: <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi,</a> triceps brachii (long head), <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a> (sternocostal head), <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a>, <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> joint capsule, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> joint capsule, coracohumeral ligament (<a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> cord), clavipectoral fascia, pectoral fascia, axillary fascia, brachial plexus</li>
 <li>Optimal Range of Motion (ROM): 120&#xB0; (180&#xB0; with full scapular upward rotation) (<a href="https://brookbushinstitute.com/video/shoulder-flexion-goniometry" target="_blank" rel="noopener">Shoulder Flexion Goniometry</a>)</li>
 </ul>
 </li>
 <li>Extension
 <ul>
 <li>Extensors: <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">Latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major</a>, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, triceps brachii (long head), <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a> (sternocostal head)</li>
 <li>Limited by: <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid,</a> <a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a>, biceps brachii, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a> (clavicular head), <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> joint capsule, coracohumeral ligament, clavipectoral fascia, pectoral fascia, deltoid fascia, brachial plexus, and nerves of the arm</li>
 <li>Optimal ROM: 20-25&#xB0; (<a href="https://brookbushinstitute.com/video/shoulder-extension-goniometry" target="_blank" rel="noopener">Shoulder Extension Goniometry</a>)</li>
 </ul>
 </li>
 <li>Internal Rotation
 <ul>
 <li>Internal Rotators: <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">Subscapularis</a>, <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a>, <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major</a></li>
 <li>Limited by: <a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">Infraspinatus, teres minor</a>, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> capsule, <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> capsule, glenohumeral ligament (<a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> and <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a>), <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> deltoid fascia, brachial plexus</li>
 <li>Optimal ROM: 60-70&#xB0; (with 90&#xB0; of abduction) (<a href="https://brookbushinstitute.com/video/shoulder-internal-rotation-goniometry" target="_blank" rel="noopener">Shoulder Internal Rotation Goniometry</a>)</li>
 </ul>
 </li>
 <li>External Rotation
 <ul>
 <li>External Rotators: <a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">Infraspinatus, teres minor</a>, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a></li>
 <li style="color: #000000;">Limited by: <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">Subscapularis</a>, <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a>, <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major</a>, <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> capsule, <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> capsule, glenohumeral ligaments (<a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a>, middle, and <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a>), coracohumeral ligament, clavipectoral fascia, pectoral fascia, brachial plexus</li>
 <li>Optimal ROM: 90-95&#xB0; (with 90&#xB0; of abduction) (<a href="https://brookbushinstitute.com/video/shoulder-external-rotation-goniometry" target="_blank" rel="noopener">Shoulder External Rotation Goniometry</a>)</li>
 </ul>
 </li>
 <li>Abduction
 <ul>
 <li>Abductors: <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> &amp; middle <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a>, biceps brachii (long head)</li>
 <li>Limited by: <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">Latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major, </a><a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a><a href="https://brookbushinstitute.com/article/teres-major" target="_blank" rel="noopener">,</a> <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a><a href="https://brookbushinstitute.com/article/teres-major" target="_blank" rel="noopener">, </a><a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a><a href="https://brookbushinstitute.com/article/teres-major" target="_blank" rel="noopener">, </a><a href="https://brookbushinstitute.com/article/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a>, <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> capsule, glenohumeral ligaments (<a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> and <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a>), coracohumeral ligament, the lower portion of brachial plexus (C8-T1)</li>
 <li>Optimal ROM: 120&#xB0; (180&#xB0; with full scapular upward rotation) see <a href="https://brookbushinstitute.com/article/upper-body-goniometry" target="_blank" rel="noopener">Upper Body </a><a id="goniometry" data-tip="1523" target="_blank" href="/glossary-term/goniometry" class="glossary">Goniometry</a>.</li>
 </ul>
 </li>
 <li>Adduction&#xA0;
 <ul>
 <li>Adductors: <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">Latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major, </a><a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a>, biceps brachii (short head), triceps brachii (long head), <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a> (below 45&#xB0; of abduction), anterior<a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener"> deltoid</a> (with the arm at side)</li>
 <li>Limited by: <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> &amp; middle <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a href="https://brookbushinstitute.com/courses/supraspinatus">supraspinatus</a>, joint capsule, possibly coracohumeral ligament, upper portion of brachial plexus (C5-6)</li>
 <li>Optimal ROM: N/A</li>
 </ul>
 </li>
 <li>Horizontal Abduction 
 <ul>
 <li>Horizontal Abductors: <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a></li>
 <li>Limited by: <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major, </a><a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a>, assuming (glenoid labrum, <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> joint capsule, glenohumeral ligaments (<a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> and middle), clavipectoral fascia, pectoral fascia, brachial plexus)</li>
 <li>Optimal ROM: 90&#xB0;</li>
 </ul>
 </li>
 <li>Horizontal Adduction 
 <ul>
 <li>Horizontal Adductors: <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">Pectoralis major</a>, <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a><a href="https://brookbushinstitute.com/article/pectoralis-major" target="_blank" rel="noopener">,</a></li>
 <li>Limited by: <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, assuming (<a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> joint capsule <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> deltoid fascia)</li>
 <li>Optimal ROM: 40&#xB0;</li>
 </ul>
 </li>
</ul>
<ul>
 <li>
 <h4>See <a id="kinesiology" data-tip="1692" target="_blank" href="/glossary-term/kinesiology" class="glossary">Kinesiology</a> of the Shoulder for a list of <a id="prime-mover" data-tip="1662" target="_blank" href="/glossary-term/prime-mover" class="glossary">prime mover</a>, <a id="synergists" data-tip="1650" target="_blank" href="/glossary-term/synergists" class="glossary">synergists</a>, antagonists, neutralizers, stabilizers, and fixators for all joint actions.</h4>
 </li>
</ul>
<a href="https://www.datocms-assets.com/25800/1642702519-1642107051-shoulder-xray.jpeg"><img src="https://www.datocms-assets.com/25800/1642702519-1642107051-shoulder-xray.jpeg" title="An X-ray of the shoulder (glenohumeral) joint" alt="Shoulder X-ray"></a>
Shoulder X-Ray - By RSatUSZ - PACS Universit&#xE4;tsSpitalZ&#xFC;rich, GFDL, https://commons.wikimedia.org/w/index.php?curid=11258999

Shoulder (Glenohumeral) Joint Actions

<a id="arthrokinematics" data-tip="1701" target="_blank" href="/glossary-term/arthrokinematics" class="glossary">Arthrokinematic motion</a> refers to the motion between joint surfaces - <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a>, <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">roll</a>, <a id="spin" data-tip="1603" target="_blank" href="/glossary-term/spin" class="glossary">spin</a>, <a id="compression" data-tip="1595" target="_blank" href="/glossary-term/compression" class="glossary">compression</a>, and distraction/traction. These <a id="arthrokinematics" data-tip="1702" target="_blank" href="/glossary-term/arthrokinematics" class="glossary">arthrokinematic motions</a> accompany <a id="osteokinematic-motion" data-tip="1796" target="_blank" href="/glossary-term/osteokinematic-motion" class="glossary">osteokinematic motions</a> to maintain joint congruence. You could visualize this pairing of motions as joint surfaces attempting to maintain the head of the humerus in contact with the glenoid fossa of the scapula. <a id="optimal" data-tip="1571" target="_blank" href="/glossary-term/optimal" class="glossary">Optimal</a> <a id="arthrokinematics" data-tip="1701" target="_blank" href="/glossary-term/arthrokinematics" class="glossary">Arthrokinematic motion</a> of the shoulder joint generally follows &quot;convex (humerus) on <a id="concave" data-tip="1281" target="_blank" href="/glossary-term/concave" class="glossary">concave</a> (scapula) rules,&quot; that is, <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a> occurs opposite to <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">roll</a> when the humerus is moving on a relatively fixed scapula. For example, during abduction of the shoulder, the humeral head rolls superiorly and <a id="glide" data-tip="1600" target="_blank" href="/glossary-term/glide" class="glossary">glides</a> inferiorly.
<h4>Arthrokinematic motion and contributing muscles:</h4>
<ul>
 <li>Compressors: All muscles of the shoulder may contribute to <a id="compression" data-tip="1595" target="_blank" href="/glossary-term/compression" class="glossary">compression</a> but most notable, acting as dynamic stabilizers, are the rotator cuff muscles: <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a>, <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a>, <a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">infraspinatus, and teres minor</a></li>
 <li>Anterior Glide: <a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">Infraspinatus, teres minor</a>, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a></li>
 <li>Posterior Glide: <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">Subscapularis</a>, <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a>, <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major</a></li>
 <li>Inferior Glide: <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">Supraspinatus</a>, <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major</a>, <a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a></li>
 <li>Superior Glide: <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">Deltoid</a>, biceps brachii (short and long heads), triceps brachii (long head), <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a> (below 45&#xB0; of abduction),</li>
</ul>
<h4 style="padding-left: 30px;">Glide is also restricted by the joint capsule and ligaments:</h4>
<ul>
 <li>Anterior Glide: Restricted by the <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> capsule, glenohumeral ligaments (<a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a>, middle, and <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a>)</li>
 <li>Posterior Glide: Restricted by the <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> capsule, <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> glenohumeral ligament</li>
 <li>Inferior Glide: Restricted by the coracohumeral ligament, <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">Inferior</a> capsule, <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">Inferior</a> glenohumeral ligament</li>
 <li>Superior Glide: Possibly coracohumeral ligament</li>
</ul>
<h4 style="padding-left: 30px;">Roll and Glide accompany the corresponding joint motion:</h4>
<ul>
 <li>Anterior <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">Roll</a> with <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">Glide</a> and Flexion: Anterior <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid,</a> <a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a>, biceps brachii, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a> (clavicular head)</li>
 <li>Posterior <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">Roll</a> with <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">Glide</a> and Extension: <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">Latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major</a>, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, triceps brachii (long head), <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a> (sternocostal head)</li>
 <li>Anterior <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">Roll</a> with <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">Glide</a> and Internal Rotation: <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">Subscapularis</a>, <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a>, <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major</a></li>
 <li>Posterior <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">Roll</a> with <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">Glide</a> and External Rotation: <a href="https://brookbushinstitute.com/article/infraspinatus-and-teres-minor" target="_blank" rel="noopener">I</a><a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">nfraspinatus, teres minor</a>, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid, </a><a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus </a>(only between neutral and full external rotation)</li>
 <li>Superior <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">Roll</a> with <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">Inferior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">Glide</a> and Abduction: <a href="https://brookbushinstitute.com/courses/deltoids">Anterior &amp; middle deltoid</a>, <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a>, biceps brachii (long head)</li>
 <li>Inferior <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">Roll</a> with <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">Superior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">Glide</a> and Adduction: <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">Latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major, </a><a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a>, biceps brachii (short head), triceps brachii (long head), <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a>, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a> (below 45&#xB0; of abduction), anterior<a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener"> deltoid</a> (with the arm at the side)</li>
 <li>Anterior <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">Roll</a> with <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">Glide</a> and Horizontal Adduction: <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">Subscapularis</a>, <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a></li>
 <li>Posterior <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">Roll</a> with <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">Glide</a> and Horizontal Abduction: posterior <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a></li>
</ul>
<h4 style="padding-left: 30px;">Spin accompanies the corresponding joint motion:</h4>
<ul>
 <li>Posterior <a id="spin" data-tip="1603" target="_blank" href="/glossary-term/spin" class="glossary">Spin</a> and Flexion: <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">Anterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid,</a> <a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">coracobrachialis</a>, biceps brachii, <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a> (clavicular head)</li>
 <li>Anterior <a id="spin" data-tip="1603" target="_blank" href="/glossary-term/spin" class="glossary">Spin</a> and Extension: <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">Latissimus dorsi</a>, <a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">teres major</a>, <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">deltoid</a>, triceps brachii (long head), <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a> (sternocostal head)</li>
</ul>
<a href="https://www.datocms-assets.com/25800/1642702571-1642107098-shoulder-cross-section.png"><img src="https://www.datocms-assets.com/25800/1642702571-1642107098-shoulder-cross-section.png" title="Shoulder cross section with muscles, ligaments, and boney landmarks labeled" alt="Cross sectional view of the shoulder joint"></a>
Shoulder Cross Section - http://eorif.com/anterior-inferior-glenohumeral-instability-m24419-71831Integrated Function

The motion of the glenohumeral joint is influenced by muscles, fascia, and the <a id="mobility" data-tip="1455" target="_blank" href="/glossary-term/mobility" class="glossary">mobility</a> of nerves that cross multiple joints. Further, the motion of <a id="proximal" data-tip="1564" target="_blank" href="/glossary-term/proximal" class="glossary">proximal</a> joints may influence the position of bones, force vectors, moment arms, and the dissipation of force.
<h4>Joints:</h4>
<ul>
 <li>Thoracic spine: In a study by Ottowa et al. thoracic kyphosis was correlated with shoulder impingement syndrome (SIS) (41).</li>
 <li>Cervical spine: Studies have shown that forward head <a id="posture" data-tip="1658" target="_blank" href="/glossary-term/posture" class="glossary">posture</a> alters <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> recruitment in overhead tasks, including a reduction in the activity of the <a href="https://brookbushinstitute.com/courses/serratus-anterior" target="_blank" rel="noopener">serratus anterior</a> in those with chronic cervical pain (35-37).</li>
 <li>Scapulothoracic joint: The relationship between the glenohumeral and scapulothoracic joint is well documented, going back to a study by Inman et al. in 1944 (22). Several studies have correlated shoulder impingement/pain with scapular <a id="dyskinesis" data-tip="1693" target="_blank" href="/glossary-term/dyskinesis" class="glossary">dyskinesis</a>, noting a reduction in <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> tipping and upward rotation and an increase in scapular internal rotation (27 - 34).</li>
</ul>
<h4>Muscles:</h4>
<ul>
 <li>All muscles crossing the shoulder and scapula (as described throughout the article)</li>
 <li>Of special consideration:
 <ul>
 <li><a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">Latissimus Dorsi</a>: Links the glenohumeral joint, scapula, lumbar spine, sacroiliac joint, and pelvis</li>
 <li><a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">Pectoralis Major</a>: Links the shoulder to the sternoclavicular and sternocostal joints</li>
 <li><a href="https://brookbushinstitute.com/courses/levator-scapulae" target="_blank" rel="noopener">Levator Scapulae</a> and <a href="https://brookbushinstitute.com/courses/trapezius-muscle" target="_blank" rel="noopener">upper trapezius</a>: Link the scapula and cervical spine</li>
 <li><a href="https://brookbushinstitute.com/courses/trapezius-muscle" target="_blank" rel="noopener">Middle and lower trapezius</a> and <a href="https://brookbushinstitute.com/courses/rhomboids" target="_blank" rel="noopener">rhomboids</a>: Link the scapula and thoracic spine</li>
 </ul>
 </li>
</ul>
<h4>Fascial Structures:</h4>
<ul>
 <li>Thoracolumbar fascia (TLF): The TLF transmits force between the <a href="https://brookbushinstitute.com/courses/gluteus-maximus" target="_blank" rel="noopener">gluteus maximus</a> and <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a> (38, 54). Further, the TLF as the central structure of the <a href="https://brookbushinstitute.com/courses/posterior-oblique-subsystem-pos" target="_blank" rel="noopener">Posterior Oblique Subsystem (POS)</a> may additionally transmit force and sensory information to the <a href="https://brookbushinstitute.com/courses/trapezius-muscle" target="_blank" rel="noopener">lower trapezius</a> and gluteus medius (54).</li>
 <li>Pectoral Fascia: The pectoral fascia is a thin lamina, covering the surface of the pectoralis major, and sending numerous extensions between fascicles. The pectoral fascia could be viewed as originating from the sternum and clavicle (underneath the platysma (2)) and coursing in multiple directions, running continuous with the fascia of the shoulder and biceps, axilla, and abdomen (54). Undercover of the <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> at the <a id="lateral" data-tip="1567" target="_blank" href="/glossary-term/lateral" class="glossary">lateral</a> border; the lamina splits to envelop the <a class="mw-redirect" title="Pectoralis minor" href="https://brookbushinstitute.com/courses/pectoralis-minor" target="_blank" rel="noopener">pectoralis minor </a>and runs continuous with the clavipectoral fascia. The axillary fascia (a blending of the pectoral and clavipectoral fascial sheaths) splits at the <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a>, one layer coursing superficial all the way to the spinous processes of the thoracic spine, the other ducking under the <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a> to envelop the <a href="https://brookbushinstitute.com/courses/serratus-anterior" target="_blank" rel="noopener">serratus </a><a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> (and potentially doubling back on itself to encase the <a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">subscapularis</a>). At the lower part of the thoracic region, the deep pectoral fascia is well-developed and is continuous with the fibrous sheaths of the <a href="https://brookbushinstitute.com/courses/rectus-abdominis-pyramidalis" target="_blank" rel="noopener">rectus abdominis</a> and <a href="https://brookbushinstitute.com/courses/external-obliques" target="_blank" rel="noopener">external obliques</a>. Although few would argue that the <a href="https://brookbushinstitute.com/courses/pectoralis-major">pectoralis major</a> and <a href="https://brookbushinstitute.com/courses/pectoralis-minor" target="_blank" rel="noopener">minor</a> muscles have synergistic functions when we examine all of the muscles mentioned in the description of the <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> <a id="axial-skeleton" data-tip="1292" target="_blank" href="/glossary-term/axial-skeleton" class="glossary">axial</a> fascia we can start to see a pushing/throwing/spiral synergy of <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> that builds on the <a href="https://brookbushinstitute.com/courses/anterior-oblique-subsystem-aos" target="_blank" rel="noopener">Anterior Oblique Subsystem (AOS).</a>
 <ul>
 <li><a href="https://brookbushinstitute.com/courses/pectoralis-major">Pectoralis major</a></li>
 <li><a class="mw-redirect" title="Pectoralis minor" href="https://brookbushinstitute.com/courses/pectoralis-minor" target="_blank" rel="noopener">Pectoralis minor</a></li>
 <li><a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">Latissimus dorsi</a></li>
 <li><a href="https://brookbushinstitute.com/courses/serratus-anterior" target="_blank" rel="noopener">Serratus anterior</a></li>
 <li><a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">Subscapularis</a></li>
 <li><a href="https://brookbushinstitute.com/courses/rectus-abdominis-pyramidalis" target="_blank" rel="noopener">Rectus abdominis</a></li>
 <li><a href="https://brookbushinstitute.com/courses/external-obliques" target="_blank" rel="noopener">External obliques</a></li>
 </ul>
 </li>
</ul>
<h4>Neural Structures:</h4>
<ul>
 <li>The motor and sensory nerves of the arm and shoulder joint originate from the c4 - c7 <a id="nerve-cell" data-tip="1361" target="_blank" href="/glossary-term/nerve-cell" class="glossary">nerve</a> roots and <a id="posture" data-tip="1660" target="_blank" href="/glossary-term/posture" class="glossary">form</a> the brachial plexus, before diverging into individual nerves. While the suprascapular, thoracodorsal, long thoracic, <a id="lateral" data-tip="1567" target="_blank" href="/glossary-term/lateral" class="glossary">lateral</a> and <a id="medial" data-tip="1568" target="_blank" href="/glossary-term/medial" class="glossary">medial</a> pectoral nerves do not cross the shoulder they may be affected by movement of the scapula and clavicle respectively. The axillary, musculocutaneous, upper, and lower subscapular nerves all cross the shoulder after passing underneath the clavicle and <a href="https://brookbushinstitute.com/courses/pectoralis-minor" target="_blank" rel="noopener">pectoralis minor</a>. The median, ulnar and radial nerves continue to cross the elbow and wrist. Upper extremity neural dysfunction may contribute to dysfunction of the cervical spine, sternoclavicular joint, acromioclavicular joint, and scapular <a id="dyskinesis" data-tip="1693" target="_blank" href="/glossary-term/dyskinesis" class="glossary">dyskinesis</a>, as well as <a id="movement-impairment" data-tip="1575" target="_blank" href="/glossary-term/movement-impairment" class="glossary">movement impairment</a> of the shoulder, elbow, and wrist.</li>
</ul>
<a href="https://www.datocms-assets.com/25800/1642702619-1642107157-brachial-plexus.jpeg"><img src="https://www.datocms-assets.com/25800/1642702619-1642107157-brachial-plexus.jpeg" title="The brachial plexus and nerves that run through the shoulder joint" alt="The brachial plexus crosses anterior to the shoulder joint"></a>
The Brachial Plexus as it crosses <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> to the shoulder joint - By Anatomist90 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=17144290

The shoulder has a propensity toward a <a id="compensation-pattern" data-tip="1696" target="_blank" href="/glossary-term/compensation-pattern" class="glossary">compensation pattern</a> often described as rounded shoulder <a id="posture" data-tip="1658" target="_blank" href="/glossary-term/posture" class="glossary">posture</a> (RSP), upper-crossed syndrome (USD), or shoulder medial/internal rotation syndrome, and these patterns often match the altered <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> activity and <a id="arthrokinematics" data-tip="1859" target="_blank" href="/glossary-term/arthrokinematics" class="glossary">arthrokinematics</a>, and <a id="osteokinematic-motion" data-tip="1881" target="_blank" href="/glossary-term/osteokinematic-motion" class="glossary">osteokinematic</a> restrictions exhibited by individuals with shoulder impingement syndrome (SIS) in research (1, 6-11, 23-26). This <a id="movement-impairment" data-tip="1575" target="_blank" href="/glossary-term/movement-impairment" class="glossary">movement impairment</a> is a combination of joint restrictions and actions &#x2013; excessive internal rotation during static and dynamic <a id="posture" data-tip="1661" target="_blank" href="/glossary-term/posture" class="glossary">postures</a>, often in conjunction with restrictions in end range flexion, external rotation and internal rotation, and potentially an increase in the <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> and <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a> of the humeral head on the glenoid fossa (1, 7-10, 23-26). Clinically and in review of applicable research, the Brookbush Institute has noted that shoulder (glenohumeral joint) impairment almost always involves scapular <a id="dyskinesis" data-tip="1693" target="_blank" href="/glossary-term/dyskinesis" class="glossary">dyskinesis</a> (article coming soon), and often involves dysfunction of the thorax and cervical spine. These changes may result in or be the result of altered length and activity of one, or many of the muscles crossing the shoulder joint, and further, result in maladaptive changes in length and/or <a id="extensibility-2" data-tip="1308" target="_blank" href="/glossary-term/extensibility-2" class="glossary">extensibility</a> of passive soft tissues (capsule, ligaments, and fascial structures). Although this section will describe dysfunction from the perspective of the shoulder; the shoulder could be viewed as the most common &quot;victim&quot; or &quot;pain generating site&quot; in those exhibiting <a href="https://brookbushinstitute.com/courses/upper-body-dysfunction-ubd" target="_blank" rel="noopener">Upper Body Dysfunction (UBD)</a>. That is, changes in upper body alignment and <a id="optimal" data-tip="1571" target="_blank" href="/glossary-term/optimal" class="glossary">optimal</a> muscular recruitment may result in excessive stress (tissue damage) to any and all tissues of the upper body, but the shoulder joint is often the first to develop considerable inflammation, nociception, and the perception of pain in the shoulder. Perhaps the increased stress placed on the shoulder for activities of daily living results in a faster rate of tissue damage and inflammation. Careful <a id="assessment" data-tip="1478" target="_blank" href="/glossary-term/assessment" class="glossary">assessment</a> of the scapula, thoracic spine, and cervical spine should be included for every patient/client exhibiting signs of shoulder dysfunction. It should also be noted that additional compensatory patterns exist and are <a id="relevance" data-tip="1505" target="_blank" href="/glossary-term/relevance" class="glossary">relevant</a> to practice; however, in this article, the focus will be given to this pattern, which is presumed to be &#x201C;most common.&#x201D;
<ul>
 <li>Common <a id="osteokinematic-motion" data-tip="1881" target="_blank" href="/glossary-term/osteokinematic-motion" class="glossary">Osteokinematic</a> Dysfunction (6-11):
 <ul>
 <li>Excessive Internal Rotation</li>
 </ul>
 </li>
 <li>Common <a id="arthrokinematics" data-tip="1863" target="_blank" href="/glossary-term/arthrokinematics" class="glossary">Arthrokinematic</a> Dysfunction (23):
 <ul>
 <li>Excessive <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a> of the humeral head on the glenoid fossa</li>
 <li>Excessive <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a> of the humeral head on the glenoid fossa</li>
 </ul>
 </li>
</ul>
<h3>Shoulder Compensatory Pattern Summary (<a href="https://brookbushinstitute.com/article/upper-body-dysfunction-ubd" target="_blank" rel="noopener noreferrer">UBD</a>)</h3>
<ul>
 <li>Maladaptive Decrease In Length/Extensibility (<a href="https://brookbushinstitute.com/video/shoulder-mobilization" target="_blank" rel="noopener noreferrer">Mobilize</a>):
 <ul>
 <li>Restricts <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a> of the humeral head on the glenoid fossa &#x2013; <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> capsule, <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> glenohumeral ligament</li>
 <li>Restricts <a id="superior" data-tip="1570" target="_blank" href="/glossary-term/superior" class="glossary">superior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a> of the humeral head on the glenoid fossa &#x2013; coracohumeral ligament and <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a></li>
 </ul>
 </li>
</ul>
<ul>
 <li>Short/Over-active (<a href="https://brookbushinstitute.com/courses" target="_blank" rel="noopener noreferrer">Release and Lengthen</a>)
 <ul>
 <li><a href="https://brookbushinstitute.com/courses/subscapularis" target="_blank" rel="noopener">Subscapularis</a></li>
 <li><a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">Supraspinatus</a></li>
 <li><a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">Latissimus dorsi</a></li>
 <li><a href="https://brookbushinstitute.com/courses/teres-major" target="_blank" rel="noopener">Teres major</a></li>
 <li><a href="https://brookbushinstitute.com/courses/coracobrachialis" target="_blank" rel="noopener">Coracobrachialis</a></li>
 </ul>
 </li>
</ul>
<ul>
 <li>Long/Over-active (<a id="synergistic-dominance" data-tip="1649" target="_blank" href="/glossary-term/synergistic-dominance" class="glossary">Synergistically Dominant</a> &#x2013; <a href="https://brookbushinstitute.com/courses" target="_blank" rel="noopener noreferrer">Release Only</a>)
 <ul>
 <li><a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">Posterior deltoid</a></li>
 </ul>
 </li>
</ul>
<ul>
 <li>Long/Under-active (<a href="https://brookbushinstitute.com/courses" target="_blank" rel="noopener noreferrer">Activate and Integrate</a>)
 <ul>
 <li><a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">Infraspinatus and teres minor</a></li>
 </ul>
 </li>
</ul>
<ul>
 <li>Short/Under-active (<a id="prime-mover" data-tip="1662" target="_blank" href="/glossary-term/prime-mover" class="glossary">Prime Mover</a> Inhibition - <a href="https://brookbushinstitute.com/courses" target="_blank" rel="noopener noreferrer">Integrate</a>)
 <ul>
 <li><a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">Anterior and middle deltoid</a></li>
 <li><a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">Pectoralis major</a></li>
 </ul>
 </li>
</ul>

Postural Dysfunction and the Shoulder Joint

<h3>Shoulder Dysfunction relative to <a href="http://brookbushinstitute.com/articles/?catId=631" target="_blank" rel="noopener noreferrer">Predictive Models of Postural Dysfunction</a></h3>
<ul>
 <li>In <a title="UBD" href="https://brookbushinstitute.com/courses/upper-body-dysfunction-ubd" target="_blank" rel="noopener">Upper Body Dysfunction (UBD)</a> the shoulder is often the joint of primary concern (for patient and practitioner alike); however, the shoulder does not function independently. Several studies have shown a strong correlation between shoulder dysfunction and scapular <a id="dyskinesis" data-tip="1693" target="_blank" href="/glossary-term/dyskinesis" class="glossary">dyskinesis</a> (27-34), shoulder/scapular <a id="dyskinesis" data-tip="1693" target="_blank" href="/glossary-term/dyskinesis" class="glossary">dyskinesis</a> and cervical dysfunction (35-37), and a study by Otoshi et al. showed a link between shoulder impingement and thoracic kyphosis (41). In essence, the shoulder functions as part of an <a id="integration" data-tip="1473" target="_blank" href="/glossary-term/integration" class="glossary">integrated</a> system of joints that include the shoulder, scapula, cervical and thoracic spine, and likely the joints of the ribs (costovertebral and sternocostal).</li>
 <li>Relative to the glenohumeral joint, the alterations in muscles activity noted in those exhibiting dysfunction may be initially explained via <a id="osteokinematic-motion" data-tip="1518" target="_blank" href="/glossary-term/osteokinematic-motion" class="glossary">osteokinematic motion</a> - an increase in activity and decrease in length of the internal rotators, and a concurrent decrease in activity and increase in length of the external rotators. This summary of activity and length is, however, complicated by <a id="synergistic-dominance" data-tip="1643" target="_blank" href="/glossary-term/synergistic-dominance" class="glossary">synergistic dominance</a>, <a id="prime-mover" data-tip="1662" target="_blank" href="/glossary-term/prime-mover" class="glossary">prime mover</a> inhibition, and <a id="trigger-point" data-tip="1632" target="_blank" href="/glossary-term/trigger-point" class="glossary">trigger point</a> development. In a study on swimmers with shoulder pain, an overall decrease in EMG activity was noted in the <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> and middle deltoid (internal rotators) (26). Relative to the <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">anterior and middle deltoid</a>, <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">posterior deltoid</a> (external rotator) activity increased (remain unchanged, despite a decrease in performance) (26). Further, in a study on <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> recruitment and <a id="latent-trigger-point" data-tip="1133" target="_blank" href="/glossary-term/latent-trigger-point" class="glossary">latent trigger points</a>, the development of <a id="latent-trigger-point" data-tip="1133" target="_blank" href="/glossary-term/latent-trigger-point" class="glossary">latent trigger points</a> in the <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">posterior deltoid</a> leads to higher levels of EMG activity in the <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">posterior deltoid</a> during shoulder flexion (24). This increase in <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">posterior deltoid</a> activity may be explained by <a id="synergistic-dominance" data-tip="1643" target="_blank" href="/glossary-term/synergistic-dominance" class="glossary">synergistic dominance</a> for a lengthened and inhibited <a href="https://brookbushinstitute.com/courses/infraspinatus-and-teres-minor" target="_blank" rel="noopener">infraspinatus and teres minor</a>. The inhibition noted in the <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">anterior and middle deltoid</a> is similar to the inhibition noted in the <a href="https://brookbushinstitute.com/courses/pectoralis-major" target="_blank" rel="noopener">pectoralis major</a> <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> of pitchers with shoulder pain (51, 52), and may be the result of &quot;prime mover inhibition&quot; in an attempt of the shoulder to protect itself from further damage. Strangely, the subscapularis also shows signs of inhibition in research on those exhibiting shoulder dysfunction (24, 53); perhaps, the altered recruitment pattern of the shoulder is better explained by altered <a id="arthrokinematics" data-tip="1859" target="_blank" href="/glossary-term/arthrokinematics" class="glossary">arthrokinematics</a>.</li>
 <li>In a study by Lawrence et al. those with shoulder pain exhibited excessive <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> and <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a> of the humeral head relative to the glenoid fossa during elevation of the arm (23). Considering the altered <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">muscle</a> activity described above, under-activity of <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> musculature and over-activity of <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">posterior</a> musculature would result in an increase in <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a> of the humeral head. Further, a decrease in <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a> length and increase in <a href="https://brookbushinstitute.com/courses/supraspinatus" target="_blank" rel="noopener">supraspinatus</a> activity would be sufficient to overcome the over-activity of the <a href="https://brookbushinstitute.com/courses/deltoids" target="_blank" rel="noopener">posterior deltoid</a>, resulting in excessive <a id="inferior" data-tip="1569" target="_blank" href="/glossary-term/inferior" class="glossary">inferior</a> <a id="glide" data-tip="1598" target="_blank" href="/glossary-term/glide" class="glossary">glide</a> of the humeral head. Although further research is needed to explore the relationship between <a id="arthrokinematics" data-tip="1863" target="_blank" href="/glossary-term/arthrokinematics" class="glossary">arthrokinematic</a> <a id="dyskinesis" data-tip="1693" target="_blank" href="/glossary-term/dyskinesis" class="glossary">dyskinesis</a> and altered activity and length of the muscles crossing the shoulder joint, it does result in less convoluted rationale.</li>
</ul>
<ul>
 <li>In <a title="LPHCD" href="https://brookbushinstitute.com/courses/lumbo-pelvic-hip-complex-dysfunction-lphcd" target="_blank" rel="noopener">Lumbo Pelvic Hip Complex Dysfunction (LPHCD)</a> and <a title="Sacroiliac Joint Motion and Predictive Model of Dysfunction" href="https://brookbushinstitute.com/courses/sacroiliac-joint-motion-and-predictive-model-of-dysfunction" target="_blank" rel="noopener">Sacroiliac Joint Dysfunction (SIJD)</a>, the shoulder does not play a role; however, the <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a> provides a bridge for the perpetuation of dysfunction from the pelvis and lumbar spine to the shoulder and visa-versa (38). The most common presentation of this link is <a title="LPHCD" href="https://brookbushinstitute.com/courses/lumbo-pelvic-hip-complex-dysfunction-lphcd" target="_blank" rel="noopener">LPHCD</a> or <a title="Sacroiliac Joint Motion and Predictive Model of Dysfunction" href="https://brookbushinstitute.com/courses/sacroiliac-joint-motion-and-predictive-model-of-dysfunction" target="_blank" rel="noopener">SIJD</a> resulting in <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a> over-activity and a loss of shoulder flexion range of motion. Although <a title="UBD" href="https://brookbushinstitute.com/courses/upper-body-dysfunction-ubd" target="_blank" rel="noopener">UBD</a> may theoretically result in <a title="LPHCD" href="https://brookbushinstitute.com/courses/lumbo-pelvic-hip-complex-dysfunction-lphcd" target="_blank" rel="noopener">LPHCD</a> or <a title="Sacroiliac Joint Motion and Predictive Model of Dysfunction" href="https://brookbushinstitute.com/courses/sacroiliac-joint-motion-and-predictive-model-of-dysfunction" target="_blank" rel="noopener">SIJD</a> via the <a href="https://brookbushinstitute.com/courses/latissimus-dorsi" target="_blank" rel="noopener">latissimus dorsi</a>, clinically, this would appear to be far less common. It has been the experience of the Brookbush Institute that in those exhibiting <a title="LPHCD" href="https://brookbushinstitute.com/courses/lumbo-pelvic-hip-complex-dysfunction-lphcd" target="_blank" rel="noopener">LPHCD</a> or <a title="Sacroiliac Joint Motion and Predictive Model of Dysfunction" href="https://brookbushinstitute.com/courses/sacroiliac-joint-motion-and-predictive-model-of-dysfunction" target="_blank" rel="noopener">SIJD</a> and a loss of shoulder flexion range of motion, shoulder flexion will return without <a id="specificity" data-tip="1224" target="_blank" href="/glossary-term/specificity" class="glossary">specific</a> intervention for the shoulder when <a title="LPHCD" href="https://brookbushinstitute.com/courses/lumbo-pelvic-hip-complex-dysfunction-lphcd" target="_blank" rel="noopener">LPHCD</a> or <a title="Sacroiliac Joint Motion and Predictive Model of Dysfunction" href="https://brookbushinstitute.com/courses/sacroiliac-joint-motion-and-predictive-model-of-dysfunction" target="_blank" rel="noopener">SIJD</a> is resolved.</li>
</ul>
<ul>
 <li>In <a title="LLD" href="https://brookbushinstitute.com/courses/lower-leg-dysfunction" target="_blank" rel="noopener">Lower Leg Dysfunction (LLD)</a>, the shoulder plays no significant role.</li>
</ul>
<a href="https://www.datocms-assets.com/25800/1642703022-1642107200-shoulder-8.jpeg"><img src="https://www.datocms-assets.com/25800/1642703022-1642107200-shoulder-8.jpeg" title="A cadaver image of the muscles crossing the shoulder joint" alt="The muscles of the shoulder joint"></a>
Iamge by Jorge Chahla - https://www.sprivail.org/publications/research-reports
<h3>Signs of changes in Range of Motion, Muscle Activity, and Length:</h3>
<ul>
 <li><a href="https://brookbushinstitute.com/courses/solutions-table-overhead-squat-assessment" target="_blank" rel="noopener">Overhead Squat Assessment</a>
 <ul>
 <li><a href="https://brookbushinstitute.com/video/overhead-squat-assessment-10-arms-fall" target="_blank" rel="noopener noreferrer">Arms Fall</a></li>
 <li><a href="https://brookbushinstitute.com/video/overhead-squat-assessment-11-shoulders-elevate" target="_blank" rel="noopener noreferrer">Shoulders Elevate</a></li>
 <li><a href="https://brookbushinstitute.com/courses/upper-body-dysfunction-ubd" target="_blank" rel="noopener">Upper Body Dysfunction</a></li>
 </ul>
 </li>
</ul>
<ul>
 <li>Goniometry (5):
 <ul>
 <li><a href="https://brookbushinstitute.com/video/shoulder-flexion-goniometry" target="_blank" rel="noopener noreferrer">Shoulder Flexion</a> &lt; 120&#xB0; (180&#xB0; with scapular motion)</li>
 <li><a href="https://brookbushinstitute.com/video/shoulder-extension-goniometry" target="_blank" rel="noopener noreferrer">Shoulder Extension</a> &lt; 25&#xB0;</li>
 <li><a href="https://brookbushinstitute.com/video/shoulder-external-rotation-goniometry" target="_blank" rel="noopener noreferrer">Shoulder External Rotation</a> &lt; 90 -95&#xB0;</li>
 <li><a href="https://brookbushinstitute.com/video/shoulder-internal-rotation-goniometry" target="_blank" rel="noopener noreferrer">Shoulder Internal Rotation</a> &lt; 60 - 70&#xB0;</li>
 </ul>
 </li>
</ul>
<ul>
 <li>Muscle <a id="muscle-length-test" data-tip="1494" target="_blank" href="/glossary-term/muscle-length-test" class="glossary">Length Tests</a> (5)
 <ul>
 <li><a href="https://brookbushinstitute.com/video/latissimus-dorsi-length-test-muscle-length-test" target="_blank" rel="noopener noreferrer">Latissimus Dorsi </a><a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">Muscle</a> Length Test</li>
 </ul>
 </li>
</ul>
<ul>
 <li>Manual <a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">Muscle</a> Testing (4):
 <ul>
 <li><a href="https://brookbushinstitute.com/video/external-rotator-manual-muscle-testing-mmt-for-an-active-population" target="_blank" rel="noopener noreferrer">Manual </a><a id="muscle-cell" data-tip="1781" target="_blank" href="/glossary-term/muscle-cell" class="glossary">Muscle</a> Testing (MMT) of the External Rotators - Weak or With Compensation</li>
 </ul>
 </li>
</ul>
<ul>
 <li>
 <h3>Clinical Issues:</h3>
 <ul>
 <li>Shoulder Impingement Syndrome (SIS)</li>
 <li>Rotator cuff tear</li>
 <li>Supraspinatus tendinopathy</li>
 <li>Bursitis</li>
 <li>Adhesive Capsulitis</li>
 <li>Shoulder Instability/Laxity</li>
 <li>Thoracic Outlet Syndrome</li>
 <li>Neuritis
 <ul>
 <li>Brachial Plexus</li>
 <li>Median Nerve</li>
 <li>Ulnar Nerve</li>
 <li>Radial Nerve</li>
 </ul>
 </li>
 <li>Osteoarthritis of the:
 <ul>
 <li>Shoulder Joint (relatively rare)</li>
 <li>Acromioclavicular Joint</li>
 <li>Sternoclavicular Joint</li>
 </ul>
 </li>
 </ul>
 </li>
</ul>

Shoulder Dysfunction and Signs of Dysfunction

Videos

<div><iframe src="https://player.vimeo.com/video/96624950" width="640" height="360" frameborder="0" allowfullscreen="allowfullscreen"></iframe></div>
<h4>Self-administered Shoulder Joint Mobilization:</h4>
<h4>Lateral Distraction</h4>
<ol>
 <li>Affix a thick &quot;<a href="https://serioussteel.com/collections/41-individual-bands" target="_blank" rel="noopener">monster band</a>&quot; to a stable object about 18&quot; from the floor (just above shoulder height when in <a href="https://brookbushinstitute.com/video/transverse-abdominis-tva-isolated-activation-quadruped" target="_blank" rel="noopener">quadruped</a> position).</li>
 <li>Place the affected arm through the band, and place the band over the most <a id="proximal" data-tip="1564" target="_blank" href="/glossary-term/proximal" class="glossary">proximal</a> portion of the <a id="medial" data-tip="1568" target="_blank" href="/glossary-term/medial" class="glossary">medial</a> arm (abutting the axilla). The band should cover part of the <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> deltoid.</li>
 <li>Assume a <a href="https://brookbushinstitute.com/video/transverse-abdominis-tva-isolated-activation-quadruped" target="_blank" rel="noopener">quadruped</a> position on knees and elbows (an ab mat or cushion may be used for comfort), perpendicular to the direction of the band. The band should be pulling the humerus from <a id="medial" data-tip="1568" target="_blank" href="/glossary-term/medial" class="glossary">medial</a> to <a id="lateral" data-tip="1567" target="_blank" href="/glossary-term/lateral" class="glossary">lateral</a>.</li>
 <li>Position the elbows underneath the shoulders with forearms parallel, or with the shoulders slightly internally rotated and hands clasped.</li>
 <li>Move far enough from the stable object to ensure <a id="tension" data-tip="1229" target="_blank" href="/glossary-term/tension" class="glossary">tension</a> is maintained on the band throughout the entire oscillation.</li>
 <li>Gently rock the entire body back and forth, trying to use bodyweight and the <a id="ipsilateral" data-tip="1550" target="_blank" href="/glossary-term/ipsilateral" class="glossary">ipsilateral</a> gluteus medius to initiate motion; less of the arm being mobilized.</li>
 <li>Continue oscillating 2 - 3&quot;, at a tempo of 1 - 2 oscillations per second, for 15 - 30 seconds.</li>
 <li>Reassess</li>
</ol>
Anterior to <a id="posterior" data-tip="1565" target="_blank" href="/glossary-term/posterior" class="glossary">Posterior</a> (<a id="cephalad" data-tip="1559" target="_blank" href="/glossary-term/cephalad" class="glossary">cranial</a> to <a id="caudal" data-tip="1557" target="_blank" href="/glossary-term/caudal" class="glossary">caudal</a>) Mobilization with Flexion (Starts at 5:25 of the video above - Note: very aggressive technique, carefully <a id="assessment" data-tip="1486" target="_blank" href="/glossary-term/assessment" class="glossary">assess</a> and reassess)
<ol>
 <li>Affix a <a href="https://serioussteel.com/collections/41-individual-bands" target="_blank" rel="noopener">monster band</a> to a low stable object, 6&quot; from the floor or less.</li>
 <li>Facing away from the wall, place the affected arm through the band, and place the band over the most <a id="proximal" data-tip="1564" target="_blank" href="/glossary-term/proximal" class="glossary">proximal</a> portion of the <a id="medial" data-tip="1568" target="_blank" href="/glossary-term/medial" class="glossary">medial</a> arm (abutting the axilla). The band should cover part of the <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> deltoid.</li>
 <li>Assume &quot;<a href="https://brookbushinstitute.com/video/latissimus-dorsi-and-erector-spinae-static-stretch-childs-pose" target="_blank" rel="noopener">Child&apos;s Pose</a>&quot; position (on knees with glutes resting on heels), facing away from the stable object you affixed the band to. (The band should be pull posterior/inferior) when you lean forward).</li>
 <li>Place your arms on a foam <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">roll</a>, TriggerPoint roller, rolled up yoga mat, or similar cylindrical object; something that will <a id="roll" data-tip="1602" target="_blank" href="/glossary-term/roll" class="glossary">roll</a> freely under your arms.</li>
 <li>As you assume &quot;<a href="https://brookbushinstitute.com/video/latissimus-dorsi-and-erector-spinae-static-stretch-childs-pose" target="_blank" rel="noopener">Child&apos;s Pose</a>&quot; position and your torso nears the floor you should feel mild <a id="tension" data-tip="1229" target="_blank" href="/glossary-term/tension" class="glossary">tension</a> from the band and potentially a similar stretching sensation that would normally be felt in this position.
 <ul>
 <li>Note: If you feel pain in this position, stop, and try the Self-administered Shoulder Mobilization: <a id="lateral" data-tip="1567" target="_blank" href="/glossary-term/lateral" class="glossary">Lateral</a> <a id="distraction" data-tip="1589" target="_blank" href="/glossary-term/distraction" class="glossary">Distraction</a> technique describe above.</li>
 </ul>
 </li>
 <li>Gently rock forward and back by pushing from your feet and legs. Do not reach with your shoulders and arms. You want the shoulder complex relatively relaxed and passive.</li>
 <li>Continue oscillating 2 - 3&quot;, at a tempo of 1 - 2 oscillations per second, for 15 - 30 seconds.</li>
 <li>Reassess</li>
</ol>

Self-administered Joint Mobilization for the Shoulder

<div><iframe src="https://player.vimeo.com/video/229793894" width="640" height="360" frameborder="0" allowfullscreen="allowfullscreen"></iframe></div>
<div>
 <h4>Manual Joint Mobilization for the Shoulder:</h4>
 <h4>Set-Up</h4>
 <ol>
 <li>The patient should be <a id="supine" data-tip="1562" target="_blank" href="/glossary-term/supine" class="glossary">supine</a>, with their scapula stabilized by the table and the head of the humerus just beyond the side of the table.</li>
 <li>The patient&apos;s arm is supported by the practitioner&apos;s hand that is nearest the table.</li>
 <li>The table should be low enough to allow the practitioner to lean forward slightly to get the chest over the arm, with the opposite palm over the humeral head and arm fully extended.</li>
 <li>Ideally, the set-up would allow the practitioner to oscillate pressure by gently rocking the torso (not by using grip or triceps strength).</li>
 </ol>
 <h4>Anterior to Posterior Mobilization</h4>
 <ol>
 <li>Standing on the side of the patient&apos;s affected arm, the patient gently holds on to the inside of the practitioner&apos;s arm, while the practitioner wraps their fingers under the patient&apos;s elbow, giving the practitioner passive control over the patient&apos;s relaxed, affected limb.</li>
 <li>The practitioner may then palpate the humeral head with the other hand, identifying the tubercles and biceps tendon, before placing the palm over the <a id="anterior" data-tip="1566" target="_blank" href="/glossary-term/anterior" class="glossary">anterior</a> surface of the humeral head with the biceps tendon in the practitioner&apos;s inter-thenar groove.</li>
 <li>The practitioner should be able to straighten the mobilizing arm, ready to apply pressure by simply leaning forward.</li>
 </ol>
 <h4>Mobilization:</h4>
 <ol>
 <li>Start with small <a id="assessment" data-tip="1482" target="_blank" href="/glossary-term/assessment" class="glossary">test</a> oscillations to identify the <a id="arthrokinematics" data-tip="1863" target="_blank" href="/glossary-term/arthrokinematics" class="glossary">arthrokinematic</a> range, the first resistance barrier, and the point that begins to push the humeral head out of the glenoid fossa.</li>
 <li>When you are satisfied with your <a id="assessment" data-tip="1482" target="_blank" href="/glossary-term/assessment" class="glossary">test</a> motions, identify the amount of pressure needed to reach the first resistance barrier and the mid-point of the <a id="arthrokinematics" data-tip="1863" target="_blank" href="/glossary-term/arthrokinematics" class="glossary">arthrokinematic</a> range.</li>
 <li>Decide the Grade of oscillation:
 <ul>
 <li>Grade III - Larger oscillations between the first resistance barrier and approximately 50% resistance. Note, these oscillations are large compared to grade IV oscillations, but are still relatively small motions.</li>
 <li>Grade IV - Small oscillations at 50% resistance or more.</li>
 </ul>
 </li>
 <li>Oscillate at 1 - 2 pulses per second.</li>
 <li>Continue oscillating until you feel a change in tissue resistance/joint stiffness.</li>
 </ol>
</div>

Manual Joint Mobilization for the Shoulder

<ol>
 <li>Donald A. Neumann, &ldquo;Kinesiology of the Musculoskeletal System: Foundations of Rehabilitation &ndash; 2nd Edition&rdquo; &copy; 2012 Mosby, Inc.</li>
 <li>David B. Jenkins, Hollinshead&rsquo;s Functional Anatomy of the Limbs and Back: Eighth Edition &copy; 2002 Saunders</li>
 <li>Cynthia C. Norkin, Pamela K. Levangie, Joint Structure and Function: A Comprehensive Analysis: Fifth Edition &copy; 2011 F.A. Davis Company</li>
 <li>Florence Peterson Kendall, Elizabeth Kendall McCreary, Patricia Geise Provance, Mary McIntyre Rodgers, William Anthony Romani, Muscles: Testing and Function with <span class="glossaryLink" data-tooltip="Posture refers to the optimal alignment of bones and joints both statically and dynamically. &ldquo;Good form&rdquo; could be defined as optimal posture during exercise.">Posture and Pain: Fifth Edition &copy; 2005 Lippincott Williams &amp; Wilkins</li>
 <li>Colby, Lynn Allen; Carolyn Kisner. Therapeutic Exercise: Foundations and Techniques (Therapeutic Exercise: Foundations &amp; Techniques) (Kindle Locations 20651-20653). F A Davis Co. Kindle Edition.</li>
 <li>Cynthia C. Norkin, D. Joyce White, Measurement of Joint Motion: A Guide to Goniometry &ndash; Third Edition. &copy; 2003 by F.A. Davis Company</li>
 <li>Phillip Page, Clare Frank, Robert Lardner, Assessment and Treatment of MuscleImbalance: The Janda Approach&copy; 2010 Benchmark Physical Therapy, Inc., Clare C. Frank, and Robert Lardner</li>
 <li>Dr. Mike Clark &amp; Scott Lucette, &ldquo;NASM Essentials of Corrective Exercise Training&rdquo; &copy; 2011Lippincott Williams &amp; Wilkins</li>
 <li>Leon Chaitow, Muscle Energy Techniques: Third Edition, &copy; Pearson Professional Limited 2007</li>
 <li>Shirley A Sahrmann, Diagnoses and Treatment of Movement Impairment Syndromes, &copy; 2002 Mosby Inc.</li>
 <li>Karel Lewit. Manipulative Therapy: Musuloskeletal Medicine &copy; 2007 Elsevier</li>
 <li>Carolyn Richardson, Paul Hodges, Julie Hides. Therapeutic Exercise for Lumbo Pelvic Stabilization &ndash; A Motor Control Approach for the Treatment and Prevention of Low Back Pain: 2nd Edition (c) Elsevier Limited, 2004</li>
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 <li>Andrew Biel, Trail Guide to the Human Body: 4th Edition, &copy; 2010</li>
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 <li>Hsu AT1, Chang JH, Chang CH. Determining the resting position of the glenohumeral joint: a cadaver study. J Orthop Sports Phys Ther. 2002 Dec;32(12):605-12.</li>
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 <li>Inman, V. T., Saunders, D.M., and Abbott, L.C. (1944). Observations on the Function of the Shoulder Joint. Journal of Bone and Joint Surgery, 26-A, 1-30
 <ul>
 <li>Altered Arthrokinematics:</li>
 </ul>
 
 </li>
 <li>Lawrence, R.L., Braman, J.P., Staker, J.L., Laprade, R.F., Ludewig, P.M. (2014) Comparison of 3-dimensional shoulder complex kinematics in individuals with and without shoulder pain, Part 2: Glenohumeral joint
 <ul>
 <li>Muscle Activity:</li>
 </ul>
 
 </li>
 <li>Jos&eacute; Miota Ibarra, Hong-You Ge, Chao Wang, Vicente Mart&iacute;nez Vizca&iacute;no, Thomas Graven-Nielsen, Lars Arendt-Nielsen. Latent Myofascial Trigger Points are Associated With an Increased Antagonistic Muscle Activity During Agonist Muscle Contraction&ndash; The Journal of Pain, Volume 12, Issue 12, December 2011, Pages 1282&ndash;1288</li>
 <li>Reinold MM, Wilk KE, Fleisig GS, Zheng N, Barrentine SW, Chmielewski T, Cody RC, Jameson GG, Andrews JR. Electromyographic Analysis of the Rotator Cuff and Deltoid Musculature During Common Shoulder External Rotation Exercises. J Orthop Sports Phys Ther. 2004 Jul;34(7):385-94</li>
 <li>Scovazzo, M.L., Browne, A., Pink, M., Jobe, F.W., and Kerrigan, J. (1991). The painful shoulder during freestyle swimming: An electromyographic cinematographic analysis of twelve muscles. The American Journal of Sports Medicine. 19(6). 577-582
 <ul>
 <li>Scapula and Movement</li>
 </ul>
 
 </li>
 <li>Ha, Sung-min., Kown, Oh-yum., Cynn, Heon-seock., Lee, Won-hwee., Park, Kyue-nam., Kim, Si-hyun., &amp; Jun, Do-young. (2012) Comparison of electromyographic activity of the lower trapezius and serratus anterior muscle in different arm-lifting scapular posterior tilt exercises. Physical Therapy in Sport, 13, 227-232</li>
 <li>Wong CK, Coleman D, diPersia V, Song J, Wright D. (2010). The effects of manual treatment on rounded-shoulder posture, and associated muscle strength. Journal of Bodywork &amp; Movement Therapies. 14: 326-333</li>
 <li>Cools, A.M., Witvrouw, E.E., Declercq, G.A., Danneels, L.A., Cambier, D.C. (2003) Scapular muscle recruitment patterns: Trapezius muscle latency with and without impingement symptoms. The American Journal of Sports Medicine 31(4). 542-549</li>
 <li>Tsai NT, McClure PW, Karduna AR. (2003). Effects of muscle fatigue on 3-Dimensional scapular kinematics. Arch Phys Med Rehabil. 84: 1000-1005
 <ul>
 <li>Altered Motion Scapula</li>
 </ul>
 
 </li>
 <li>Ludewig P.M., Cook, T.M. (2000) Alterations in shoulder kinematics and associated muscle activity in people with symptoms of shoulder impingement. Physical Therapy. 80 (3) 276-291</li>
 <li>Lawrence, R. L., Braman, J. P., Laprade, R. F., &amp; Ludewig, P. M. (2014). Comparison of 3-dimensional shoulder complex kinematics in individuals with and without shoulder pain, part 1: sternoclavicular, acromioclavicular, and scapulothoracic joints. journal of orthopaedic &amp; sports physical therapy, 44(9), 636-A8</li>
 <li>Fayad F, Roby-Brami A, Yazbeck C, Hanneton S, Lefevre-Colau MM, Gautheron V, Poiraudeau S, Revel M. (2008). &ldquo;Three-dimensional scapular kinematics and scapulohumeral rhythm in patients with glenohumeral osteoarthritis or frozen shoulder.&rdquo; 2008 Jbiomech, 41(2): 326-332
 <ul>
 <li>Regional Interdependence:</li>
 </ul>
 
 </li>
 <li>Suzuki, H., Swanik, K. A., Huxel, K. C., Kelly, J. D., &amp; Swanik, C. B. (2006). Alterations in upper extremity motion after scapular-muscle fatigue. Journal of Sport Rehabilitation, 15(1), 71</li>
 <li>Kwon JW, Son SM, Lee NK. (2015). Changes in upper-extremity muscle activities due to head position in subjects with a forward head posture and rounded shoulders. J Phys Ther Sci. 27: 1739-1742</li>
 <li>Helgadottir, H., Kristjansson, E., Einarsson, E., Karduna, A., &amp; Jonsson, H. (2011). Altered activity of the serratus anterior during unilateral arm elevation in patients with cervical disorders. Journal of electromyography and kinesiology,21(6), 947-953</li>
 <li>Thigpen CA, Padua DA, Michener LA, Guskiewicz K, Giuliani C, Keener JD, Stergiou N. (2010). Head and shoulder posture affect scapular mechanics and muscle activity in overhead tasks. Journal of Electromyography and Kinesiology. 20: 701-709</li>
 <li>Carvalhais, VO., Ocarino, Jde M., Ara&uacute;jo, VL., Souza, TR., Silva, PL., Fonseca, ST. (2012). Myofascial force transmission between the latissimus dorsi and gluteus maximus muscles: An in vivo experiment. Journal of Biomechanics 46. 1003-1007</li>
 <li>Ayhan, C., Camci, E., &amp; Baltaci, G. (2015). Distal radius fractures result in alterations in scapular kinematics: A three-dimensional motion analysis. Clinical Biomechanics</li>
 <li>Day, J. M., Bush, H., Nitz, A. J., &amp; Uhl, T. L. (2015). Scapular Muscle Performance in Individuals With Lateral Epicondylalgia. Journal of Orthopaedic &amp; Sports Physical Therapy, (Early Access), 1-35</li>
 <li>Otoshi, K., Takegami, M., Sekiguchi, M., Onishi, Y., Yamazaki, S., Otani, K., Shishido, H., Shinichi, K., Shinichi, K. (2014). Association between kyphosis and subacromial impingement syndrome: LOHAS study. Journal of Shoulder and Elbow Surgery. 23. e300-e307
 <ul>
 <li>Exercise</li>
 </ul>
 
 </li>
 <li>Suprak DN, Bohannon J, Morales G, et al. (2013). Scapular kinematics and shoulder elevation in a traditional push-up. Journal of Athletic Training. 48(6): 826-835</li>
 <li>Ha, S., Kwon, O., Cynn, H., Lee, W., Kim, S., Park, K. (2013). Selective activation of the infraspinatus muscle. Journal of Athletic Training. 48(3). 346-352</li>
 <li>Dark A, Ginn KA, Halaki M. (2007). Shoulder muscle recruitment patterns during commonly used rotator cuff exercises: an electromyographic study. Pys Ther. 87: 1039-1046</li>
 <li>Kaya, E., Zinnuroglu, M., Tugeu, I. (2010) Kinesio taping compared to physical therapy modalities for the treatment of shoulder impingement syndrome. Clinical Rheumatology. (30) 201-207</li>
 <li>Wang, C., McClure, P., Pratt, N., Nobilini, R. Stretching and Strengthening Exercises: Their Effect on Three-Dimensional Scapular Kinematics. Arch Phys Med Rehabil. 1999 vol. 80, 923-929</li>
 <li>Cools, A.M., Dewitte, V., Lanszweert, F., Notebaert, D., Roets, A., Soetens, B., Cagnie, B., Witvrouw, E.E. (2007) Rehabilitation of Scapular Muscle Balance. Which Exercises to Prescribe? Am J Sports Med, 35(10), 1744-1751</li>
 <li>Uhl, T. L., Carver, T. J., Mattacola, C. G., Mair, S. D., &amp; Nitz, A. J. (2003). Shoulder musculature activation during upper extremity weight-bearing exercise. Journal of Orthopaedic &amp; Sports Physical Therapy, 33(3), 109-117</li>
 <li>Reed D, Cathers I, Halaki M, Ginn KA. (2015). Does load influence shoulder muscle recruitment patterns during scapular plane abduction? Journal of Science and Medicine in Sport.</li>
 <li>Hardwick DH, Beebe JA, McDonnell MK, Lang CE. (2006). A comparison of serratus anterior muscle activation during a wall slide exercise and other traditional exercises. Journal of Orthopaedic &amp; Sports Physical Therapy. 36(12) 903-910
 <ul>
 <li>Pectoralis Inhibition</li>
 </ul>
 </li>
 <li>Wang HK, Cochorane T. 2001. Mobility impairment, muscle imbalance, muscle weakness, scapular asymmetry and shoulder injury in elite volleyball athletes. J Sport Med Phys Fitness 41(3): 403-10</li>
 <li>Glousman R, Jobe F, Tibone J, Moynes D, Antonelli D, Perry J. Dynamic Electromyographic analysis of the throwing shoulder with glenohumeral instability. J Bone <span class="glossaryLink " data-tooltip="Where two or more bones meet.&lt;br /&gt;Etymology: joint (n.) late 13c., &ldquo;a part of a body where two bones meet and move in contact with one another,&rdquo; from Old French joint &ldquo;joint of the body&rdquo; (12c.), from Latin iunctus &ldquo;united, connected, associated,&rdquo; past participle ofiungere &ldquo;join&rdquo; (see &lt;a href=&quot;http://www.etymonline.com/index.php?term=jugular&amp;allowed_in_frame=0&quot;&gt;jugular&lt;/a&gt;). (&lt;a href=&quot;http://www.etymonline.com/index.php?term=joint&quot;&gt;Etymology Online&lt;/a&gt;)">Joint Surg 70A(2):220-226, 1988.</li>
 <li>Glousman R, Jobe F, Tibone J, Moynes D, Antonelli D, Perry J. Dynamic Electromyographic analysis of the throwing shoulder with glenohumeral instability. J Bone Joint Surg 70A(2):220-226, 1988
 <ul>
 <li>Fascia</li>
 </ul>
 
 </li>
 <li>Schleip R; Findley T; Chaitow L., Huijing P. Fascia: The Tensional Network of the Human Body &copy; 2012 Elsevier Ltd.</li>
</ol>

Bibliography

<html><head></head><body>© 2016 Brent Brookbush
Questions, comments and criticisms welcome and encouraged </body></html>

Copyright

A-Band - Refers to the part of the muscle cell that looks darker under a microscope.  This area of the cell is darker due to parallel arrangement of thicker filaments (myosin) and overlap with the thinner filaments (actin).
<ul>
 	<li>As a muscle contracts, the A-band is where actin and myosin interact.</li>
</ul>
<ol>
 	<li>Saladin, K. (2014). Anatomy &amp; physiology: The unity of form and function. McGraw-Hill Higher Education, New York. ISBN: 9780073403717</li>
</ol>

Accuracy - the proportion of individuals correctly identified by the test results.
<ul>
 	<li>For example, a special test with perfect accuracy would imply a test has 100% specificity, 100% sensitivity, 100% positive predictive value and 100% negative predictive values.</li>
</ul>

Action Potential - A rapid change in voltage, resulting in a wave of excitation, that may result in stimulation of a nerve or muscle cell.
<ul>
 	<li>In order for an action potential to be initiated, the resting membrane voltage must exceed the excitation threshold, which then results in a cascade of depolarization and the "wave of excitation." Any stimulus below that threshold will not result in an action potential, and a stimulus greater than the threshold will not increase a single action potential, but may result in additional action potentials.  In this way, the action potential functions more like an on/off switch (all or none), and less like a dimmer switch.</li>
</ul>

A single-joint movement pattern (most often) designed to load a specific under-active muscle(s), while minimizing the contribution of over-active synergists via specific cues/joint motions.
<ul>
 	<li style="text-align: left;">Activation techniques/exercises are performed with the intent of addressing a muscle exhibiting a reduction in activity (tone) as a result of, or contributing to postural dysfunction.</li>
 	<li style="text-align: left;">Activation techniques/exercises cannot be multi-joint movement patterns due to relative flexibility, altered reciprocal inhibition, and synergistic dominance resulting in compensation patterns.</li>
</ul>
Example, <a href="https://brentbrookbush.com/articles/corrective-exercise-articles/activation/gluteus-medius-activation-progression/" target="_blank">gluteus medius activation</a> involves resisted hip abduction while minimizing the contribution of the TFL via hip extension.

Active stretching is a term used to describe a stretch that involves an active contraction of opposing musculature to lengthen a muscle to its end range. Generally these stretches are held for 2-5 seconds and repeated for 8-15 repetitions.

Adenosine triphosphatase (ATPase): is the enzyme responsible for catalyzing (initiating and accelerating) the decomposition of ATP to ADP.
<ul>
 	<li>This dephosphorylation (breakdown) reaction releases energy for processes like muscular contraction.</li>
</ul>

Adenosine triphosphate (ATP): The molecule that functions as a universal energy-transfer molecule, providing most of the energy associated with muscular contraction and human movement. ATP is composed of an adenine group, a ribose group, and three molecules of inorganic phosphates.
<ul>
 	<li>Energy is provided when hydrolysis results in the cleaving of a phophate group; resulting in adenosine diphosphate, an inorganigic phosphate group, and energy.</li>
</ul>

Algometry - measuring the amount of pressure to result in sensitivity or pain, using an algometer.
<ul>
 	<li>Generally, research uses algometry to establish a minimum pain pressure threshold (PPT), in which a lower PPT implies more sensitivity and pain, and a higher PPT implies less sensitivity and pain. PPT is a common outcome measure in trigger point research.</li>
</ul>
<a href="https://brentbrookbush.com/wp-content/uploads/2019/07/Algometer.jpg"><img class="aligncenter wp-image-140177" src="https://brentbrookbush.com/wp-content/uploads/2019/07/Algometer.jpg" alt="Image of an Algometer" width="500" height="333" /></a>

All-or-none principle - a nerve or muscle cell's response to a stimulus is independent of the strength of the stimulus. If that stimulus exceeds the threshold potential (threshold of an action potential), the nerve or muscle fiber will respond completely; otherwise, there is no response.

Example, when a motor unit in the biceps brachii is stimulated it contracts the same way whether a 10 lb or 50 lb dumbbell is lifted.  It is actually the number of muscle cells and the size of the motor unit that determines force output.

&nbsp;

The transition period between eccentric load and concentric contraction during a repetition of an exercise.  This term is most often used in reference to power/plyometric exercises, in which a shorter amortization phase is believed to be beneficial.  The shorter amortization phase may better use the stored energy from the elastic deformation of connective tissue and enhance synchronization of myotatic (stretch) reflex with maximum voluntary contraction.

Example, the athlete was cued to spend as little time as possible in the bottom of their squat stance (the amortization phase) during a set of box jumps.

Muscles that oppose the prime mover and synergists for a given joint action.

That is, all the muscles that can perform the opposing joint action.

Example: The triceps and anconeus are antagonists during elbow flexion.

An anatomical direction; toward the front

Example, the face is on the anterior aspect of the head

Appendicular Skeleton - referring to the bones the bones of the arms and legs, as well as the bones that support them. This includes the pelvis, clavicle and scapula. There are approximately 126 bones in the appendicular skeleton.
<ul>
 	<li>Etymology - Appendicular, as in appendage, "that which is appended to something as a proper part," 1640s, from <a class="crossreference" href="https://www.etymonline.com/word/append?ref=etymonline_crossreference">append</a> + <a class="crossreference" href="https://www.etymonline.com/word/-age?ref=etymonline_crossreference">-age</a>. - <a href="https://www.etymonline.com/word/appendage" target="_blank" rel="noopener">Etymology Online</a></li>
</ul>
"Appendicular skeleton" is a label referring to a set of bones whose function is distinct from the bones of the "<a href="https://brentbrookbush.com/glossary/axial-skeleton/" target="_blank" rel="noopener">axial skeleton</a>".

A reflexive decrease in muscle activity due to joint dyskinesis.
For example, a reduction in deep cervical flexor activity as a result of cervical spine dyskinesis.

Arthrokinematic Motion - Small amplitude motions between bone surfaces at a joint.  The arthrokinematic motions are roll, glide (slide or translation), spin, compression and distraction (traction). Arthrokinematic motions accompany osteokinematic motions to maintain joint congruence.
<ul>
 	<li>Example, arthrokinematic motion of the talus includes posterior glide on the tibia during ankle dorsiflexion.</li>
</ul>
Synonyms include: arthrokinematics, passive accessory motion, joint play and component motion

&nbsp;

Assessment - is the act of assessing, i.e. determining the importance, size, or value of -

In most cases, the results of an assessment are compared to normative data. If the individual exhibits values that are within normal parameters, it may be assumed that the aspect of health or motion assessed is not contributing to the patient's complaint, symptoms or movement impairment. If the results fall outside of normal parameters, it may indicate that the aspect of health or motion assessed is contributing to, or being affected by the patient/client's complaint, symptoms, or movement impairment. In some cases, the results of an assessment are compared to an "ideal model." In this case, deviations from the ideal are noted as potential issues. For example, deviations noted in the <a title="Introduction to the Overhead Squat Assessment" href="https://brentbrookbush.com/online-courses/articles/assessment/introduction-overhead-squat-assessment/" target="_blank">Overhead Squat Assessment</a> are compared to an "ideal model" of posture and motion.

Assessments used by human movement professionals can be divided into three broad categories:
<ul>
 	<li>"Clear" the Patient/Client for Intervention - These are tests, assessments and evaluations used to determine if a patient/client's issue may improve given the assessing professional's scope, skills, abilities and willingness to treat that individual.
<ul>
 	<li>For example, many of the special tests used in orthopedic medicine assist in determining the level of pathology or likelihood of a particular diagnosis. Certain issues and diagnoses are beyond the scope of the human movement professional, and are better treated by diagnostic professionals in the medical community (physicians, podiatrists, surgeons, etc.). A Calf Squeeze (Thompson) Test is one example, in which a positive sign may indicate a rupture of the Achilles tendon that may be better treated via surgical intervention.</li>
</ul>
</li>
 	<li>Highlight Contraindications - Tests, assessments and evaluations used to stratify risk or preclude a professional from addressing certain tissues, motions or using a particular technique.
<ul>
 	<li>For example, the Vertebral Artery Test (VBI) is often used to determine if high velocity thrust mobilizations (manipulations) are safe for a patient with cervical dysfunction.</li>
</ul>
</li>
 	<li>Refine Exercise/Intervention Selection: Tests, assessments and evaluations used to assist the professional in determining which techniques, modalities and exercises will best address a patient/client's complaints or desired goals.
<ul>
 	<li>Most movement assessments fall into this category. For example, a positive <a href="https://brentbrookbush.com/vimeo_videos/elys-test-rectus-femoris-flexibility-assessment/" target="_blank">Ely's Test</a> may indicate a need to release and/or lengthen the <a href="https://brentbrookbush.com/articles/anatomy-articles/muscular-anatomy/rectus-femoris/" target="_blank">rectus femoris</a>.</li>
</ul>
</li>
</ul>
Note: An assessment, or assessment result, may fall into more than one category. For example, although goniometry is an assessment most often used to Refine Exercise/Intervention Selection, if a range of motion is significantly altered, with an abnormal end-feel, and/or causes the patient or client/pain, the individual may need to be referred to a physician for further testing and Clearance to resume rehab activities.  Further, that same patient may return to the human movement professional with a list of Contraindicated Activities from the physician. - "When in doubt, refer out!"

Axial Skeleton - referring to the bones of the head, neck, trunk and spinal column (does not include pelvis). There are approximately 80 bones in the axial skeleton.
<ul>
 	<li>Etymology - Axial, as in "axis", referring to "imaginary motionless straight line around which a body (such as the Earth) rotates," from Latin axis "axle, pivot, axis of the earth or sky" - <a href="https://www.etymonline.com/word/axis" target="_blank" rel="noopener">Etymology Online</a></li>
</ul>
"Axial skeleton" is a label referring to a set of bones whose function is distinct from the bones of the "<a href="https://brentbrookbush.com/glossary/appendicular-skeleton/" target="_blank" rel="noopener">appendicular skeleton</a>".

Balance - The ability to maintain a body’s center of mass over its base of support. Balance can be static or dynamic.
<ul>
 	<li>For example, maintaining balance is harder on one leg because the center of mass must stay over a much smaller base of support.</li>
</ul>

A ball and socket joint (also called a spheroid joint or spheroidal joint) is a synovial joint in which the rounded or spherical end of one bone fits into a cup-like depression of another bone. The distal bone is capable of motion around an indefinite number of axes, which have one common center. Examples include the hip and shoulder (glenohumeral joint)

Base of support (BoS) - refers to the area beneath an object or person, and the area within the perimeter created by every point of contact that the object or person makes with the supporting surface. This may include the <a href="https://brentbrookbush.com/articles/anatomy-articles/muscular-anatomy/gluteus-maximus/" target="_blank" rel="noopener">glutes</a> of someone sitting on a chair, or the back of someone leaning against a wall.
<ul>
 	<li>For example, during a single leg balance the BoS is the area of the foot in contact with the surface; however, when a person is standing on two feet, the BoS is the area of both feet and the surface between them.</li>
</ul>

Pertaining to both sides

Example, bilateral rows are performed with both arms at the same time.

Case-control Study - a particular form of retrospective study that samples a matched group of people who have, and do not have the outcome being studied. A case-control study is a quasi-experimental design, often used in medicine to aid in determining potential contributing factors (cannot determine causality). In this study type exposure is the dependent variable and outcome is independent.
<ul>
 	<li>Example, in this retrospective case-control, medical records were investigated for trends correlated with cervical pain (1).
<ol>
 	<li>Mäkela, M., Heliövaara, M., Sievers, K., Impivaara, O., Knekt, P., &amp; Aromaa, A. (1991). Prevalence, determinants, and consequences of chronic neck pain in Finland. American journal of epidemiology, 134(11), 1356-1367.</li>
</ol>
</li>
</ul>

An anatomical direction; toward the tail, relative to humans this term is often used to refer to "in the direction of the tale (toward the feet)".

Example, to release the trapezius muscle the therapist used a force directed caudally.

Center of mass (CoM) - an object's mean position of mass; that is, a point that is perfectly surrounded by an equal amount mass in all directions.

Center of gravity (CoG) - point where gravity appears to act. Since the human body is so small compared to the earth, we can assume gravity acts uniformly on the body, and that CoG and CoM are the same.
<ul>
 	<li>Example, the CoM of the human body while lying down or standing straight up is close to our navel. However, it is possible that during a resistance exercise, the combination of the body's weight and the weight of the resistance will place the combined CoM outside the body. For example, during the mid-portion of a <a href="https://brentbrookbush.com/vimeo_videos/back-squat/" target="_blank" rel="noopener">back squat</a> the CoM would be several anterior to the naval.</li>
</ul>

An anatomical direction; toward the head (synonym: cranial)

Example, hip pain was felt with any force directed cephalad.

Cohort Study - a particular form of longitudinal study that samples a cohort (a group of people who share a defining characteristic), performing a cross-section at intervals through-out a period of time. A cohort study is a quasi-experimental design often used in medicine to aid in determining etiology or a cause-and-effect relationship. In this study type exposure is the independent variable and outcome is dependent.
<ul>
 	<li>Example, the study by Cholewicki et al. (1) investigated Yale Varsity Athletes (the cohort) with 2 and 3 year follow up (longitudinal design) and found that trunk muscle response time to off-loading was predictive of future low back injury.</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/core/increased-trunk-muscle-latency-may-cause-rather-than-result-from-low-back-pain/" target="_blank" rel="noopener noreferrer">Cholewicki, J., Silfies, S., Shah, R., Greene, H., Reeves, N. Alvi, K., Goldberg, B. (2005). Delayed trunk muscle reflex responses increase the risk of low back injuries. Spine. 30(23), 2614-2620</a></li>
</ol>

Comparable Sign: A combination of pain, stiffness and/or spasm during examination that is comparable to the patients symptoms.
<ul>
 	<li>One common error made during evaluation with special tests is attention given to any discomfort or pain, rather than attempting to identify the pain/discomfort related to the patient's complaint (concordant/comparable sign). Many special tests purposefully test tissue limits and are at least mildly uncomfortable in every individual. Basing your assessment on positive tests that resulted in "concordant/comparable signs" will improve your chances of arriving at the correct diagnosis.</li>
</ul>

An alternative movement pattern that has been adopted to compensate for dysfunction/impairment in the human movement system.
Example: A lack of calf extensibility may limit dorsiflexion, leading to the knees bowing inward (functional valgus) and excessive forward lean of the torso during a squat.

An arthrokinematic motion - the approximation of joint surfaces; that is, a force that directs one bone surface into another resulting in a reduction in intra-articular volume. Although widely thought of as a "destructive force", it is likely best to consider compression as a naturally occurring, stabilizing force. Any arthrokinematic force in excess (spin, glide, roll, traction) may be viewed as potentially deleterious.

For example, during a squat the femoral head is compressed into the acetabulum by muscular forces, bodyweight and any additional external load.

Concave (Concavity) - Having an outline or surface curved like the interior surface of a bowl or sphere - to cave-in or curve inward.
<ul>
 	<li>Example, the internal surfaces of the pelvis is concave, holding some of the bodies viscera.</li>
</ul>

Concordant Sign - The patient's specific pain, symptom or complaint. 
<ul>
 	<li>One common error made during evaluation with special tests is attention given to any discomfort or pain, rather than attempting to identify the pain/discomfort related to the patient's complaint (concordant/comparable sign). Many special tests purposefully test tissue limits and are at least mildly uncomfortable in every individual. Basing your assessment on positive tests that resulted in "concordant/comparable signs" will improve your chances of arriving at the correct diagnosis.</li>
</ul>

Conductivity: Stimulation results in more than a local effect (1).
<ul>
 	<li>For example, in a muscle cell the stimulation of a motor endplate results in a change in cell membrane polarity that rapidly propagates (is conducted) along the entire length of the muscle cell, stimulating all sacromere.</li>
</ul>
<ol>
 	<li>Saladin, K. (2012). Anatomy &amp; Physiology: The unity of form and function. (6th ed.). New York: McGraw-Hill.</li>
</ol>

A condyloid joint (also called condylar, bicondylar, ellipsoid, or ellipsoidal) is an ovoid articular surface, or condyle, that is received into an elliptical cavity.  These joints permit movement in two planes.  Examples include the knee, metacarpophalangeal joints and metatarsophalangeal joints.

Connective Tissue Cell - One of the four basic types of animal tissue, consisting mostly fibers and ground substance.  These cells are specialized to binds organs together, holds them in place, protect them from external forces, and may fill space in the body's cavities.

Example, the body's muscles are enclosed in durable connective tissue sheets known as the "epimysium", "perimysium", and "endomysium," which and in support and transmitting force.
<ol>
 	<li>Saladin, K. (2014). Anatomy &amp; physiology: The unity of form and function. McGraw-Hill Higher Education, New York. ISBN: 9780073403717</li>
</ol>

Contractility: The ability to shorten (1).
<ul>
 	<li>Contractility: Muscle cells are unique in the amount they can shorten when stimulated; this is this largerly due to the highly organized and unique arrangement of myofilaments (actin and myosin).</li>
</ul>
<ol>
 	<li>Saladin, K. (2012). Anatomy &amp; Physiology: The unity of form and function. (6th ed.). New York: McGraw-Hill.</li>
</ol>

Pertaining to the opposite side

Example, the external oblique muscle performs contralateral rotation; rotation to the opposite side.

Convex (Convexity) - Having an outline or surface curved like the exterior of a circle or sphere - to bulge or curve outward.
<ul>
 	<li>Example, the top of your head is shaped by the convex exterior surface of your skull.</li>
</ul>

Correlational Research - Non-experimental <a href="https://www.questionpro.com/blog/what-is-research/">research</a> method in which the statistical relationship between two variables is investigated.
<ul>
 	<li>In this research by Kwon et al., a correlation was noted between a decrease in extensibility during a hamstring length test (goniometry) and current knee pain (1).</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/knee/correlation-patellofemoral-pain-syndrome-pfps-hamstring-activity/" target="_blank" rel="noopener">Kwon O, Yun M, and Lee W. (2014). Correlation between intrinsic patellofemoral pain syndrome in young adults and lower extremity biomechanics. J. Phys. Ther. Sci. 26: 961-964</a></li>
</ol>

Counter-nutation - posterior rotation of sacrum relative to ilium, and/or anterior rotation of ilium relative to sacrum.
<ul>
 	<li>The pelvic floor muscles are examples of muscle that may counter-nutate the sacrum.</li>
</ul>
[caption id="attachment_126335" align="aligncenter" width="400"]<a href="https://brentbrookbush.com/wp-content/uploads/2018/10/Nutation.png"><img class=" wp-image-126335" src="https://brentbrookbush.com/wp-content/uploads/2018/10/Nutation.png" alt="Nutation and Counter-nutation of the Sacroiliac Joint" width="400" height="967" /></a> Nutation and Counter-nutation of the Sacroiliac Joint[/caption]

&nbsp;

Crossover (Study) Design - A type of longitudinal, repeated measures quasi-experimental design in which each group receives both treatments, but at different times. It is named "crossover" due to the patients "crossing-over" to the other treatment or sham group after a specified period of time.
<ul>
 	<li>This type of study has the advantage of every individual serving as their own control, which may reduce the influence of confounding variables.</li>
 	<li>Unfortunately, the design itself introduces the chances that anyone receiving the experimental variable in the first period will continue to be effected in the second period.</li>
</ul>
In a study by Senna et al., a cross-over design was used to investigate the difference load made on inter-set rest intervals (1).
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/strength-training-research-corner/heavy-vs-light-load-single-joint-exercise-performance-with-different-rest-periods/" target="_blank" rel="noopener">Senna, G.W., Rodrigues, B.M., Sandy, Scudese, Bianco, A, &amp; Dantas, E.H.M. (2017). Heavy vs light load single-joint exercise performance with different intervals. Journal of Human Kinetics, 58, 197-206. </a></li>
</ol>

Cross-sectional Study - a research design that involves gathering data from a population or representative subset at a specific point in time.
<ul>
 	<li>Example, the study by Karimi-Mobarake et al.(1) investigated the prevalence of genu varum and genu valgum among school children 7-11 years old in Iran.</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/knee/low-prevalence-of-genu-varum-and-valgum-among-elementary-school-children/" target="_blank" rel="noopener noreferrer">Karimi-Mobarake, M., Kashefipour, A., Yousfnejad, Z. The prevalence of genu varum and genu valgum in primary school children in Iran 2003-2004. (2005) Journal of Medical Science 5(1). 52-54</a></li>
</ol>

Cytokine - A broad and loose category of small proteins that act through receptors, and are especially important to immune function (inflammation).
<ul>
 	<li>Cytokines include substances such as interferon, interleukin, and growth factors, which are secreted by certain cells of the immune system and have an effect on other cells. Their definite distinction from hormones is a topic of continued research.</li>
</ul>
&nbsp;

Dependent variable - in research, this is the variable that is changed by the independent variable, most often this is the "outcome" of the study.
<ul>
 	<li>Example, in the study by Cleland et al. (1), the independent variable is "thoracic manipulation," and the dependent variable is "lower trapezius muscle strength."</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/short-term-effects-lower-thoracic-manipulation-lower-trapezius-muscle-strength/" target="_blank" rel="noopener noreferrer">Cleland J, Selleck B, Stowell T, Brown L, Alberini S, St. Cyr H, Caron T. Short-term Effects of Thoracic Manipulation on Lower Trapezius Muscle Strength.  Journal of Manual &amp; Manipulative Therapy. 2004; 12(2): 82-90</a></li>
</ol>

An anatomical direction; further from the trunk or center of the body

Example, the foot is at the distal end of the leg.

An arthrokinematic motion - a force applied to a body part that may result in the separation of joint surfaces, a reduction in intra-articular pressure, and/or an increase in intra-articlar space.

For example, to hang from one's hands (i.g. in preparation for a pull-up) results in a traction force on the glenohumeral joint (shoulder).

An anatomical term of location; back or upper surface

Example, shoe laces may compress tissues on the dorsal surface of the foot

The "drawing-in" maneuver is a common cue used during exercise and rehabilitation programs. A light contraction of the <a href="https://brentbrookbush.com/articles/muscular-anatomy/transverse-abdominis/" target="_blank" rel="noopener">transverse abominis</a> (and potentially the entire <a href="https://brentbrookbush.com/articles/corrective-exercise-articles/core-subsystems/intrinsic-stabilization-subsystem/" target="_blank" rel="noopener">intrinsic stabilization subsystem</a>) achieved by gently pulling the lower abdominal region away from one's waist band. This should have minimal effect on breathing, and should not be confused with a maximal contraction of the <a href="https://brentbrookbush.com/articles/muscular-anatomy/transverse-abdominis/" target="_blank" rel="noopener">transverse abdominis</a> resulting in a "vacuum pose".
<ul>
 	<li>Research often refers to this maneuver as the "abdominal drawing-in maneuver"; abbreviated ADIM.</li>
</ul>
Development and introduction of this cue into practice is based on the pivotal research and resulting text:
<ol>
 	<li>Carolyn Richardson, Paul Hodges, Julie Hides. Therapeutic Exercise for Lumbo Pelvic Stabilization – A Motor Control Approach for the Treatment and Prevention of Low Back Pain: 2nd Edition (c) Elsevier Limited, 2004</li>
</ol>

Faulty or abnormal movement; an alteration of normal kinematics.

For example, joint stiffness or a reduction in arthrokinematics motion that results in limited osteokinematic range of motion - inadequate inferior glide of the femoral head resulting in limited abduction of the hip.

The seeping into, or abnormal collection of fluid in a body cavity.

For example, knee effusion describes swelling within the knee joint.

Note: the word "effusion" is used differently in medicine than it is used in reference to the movement (seeping out) of liquids and gases, for example in chemistry.

&nbsp;

A trait of body tissues that allows a tissue to return to its resting length or state after deformation or stretch.
Example:  Muscle is elastic tissue; many muscles will return to their resting length after being stretched to 150% of that length without any appreciable change in tissue quality.

Elasticity: Elasticity refers to the ability of a cell to return to its resting length after being stretched/lengthened.
<ul>
 	<li>Note: this term is often confused with extensibility. Elasticity is not the ability to stretch; it is the ability to return to normal length after being stretched. Muscle tissue, connective tissue and even nerve tissue have varying levels of elasticity.</li>
</ul>
<ol>
 	<li>Saladin, K. (2012). Anatomy &amp; Physiology: The unity of form and function. (6th ed.). New York: McGraw-Hill.</li>
</ol>

Epithelial cell - One of the four basic cell types, found lining the body's cavities, blood vessels, organs and constitutes most gland tissue.  These cells are specialized to aid with absorption, secretion, or act as a barrier from foreign objects.
<ol>
 	<li>Saladin, K. S., &amp; Miller, L. (1998). Anatomy &amp; physiology. New York (NY): WCB/McGraw-Hill.</li>
</ol>

Equilibrium - a state in which opposing forces or influences are balanced.
<ul>
 	<li>For example, to maintain a neutral trunk while pushing or pulling a weight in one hand, your core musculature must balance the force by creating an equal amount of force in the opposite direction.</li>
</ul>

The study of causation, or origination. The word is commonly used in the medical professions, where it may refer to the study of why things occur, or the reason behind why things act a certain way.

For example, the etiology of low back pain is a complex subject, with multiple contributing factors and various structures implicated.

<div class="gs_citr" tabindex="0">Evidence-based medicine (practice) is the integration of best research evidence with clinical expertise and patient(client) values (2)."</div>
<ul>
 	<li class="gs_citr" tabindex="0">...the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients (clients).  It involves the integration of at least (a) clinical expertise/expert opinion, (b) external scientific evidence, and (c) client/patient/caregiver perspectives to provide high-quality services reflecting the interests, values, needs, and choices of the individuals we serve (1).</li>
</ul>
&nbsp;
<ol>
 	<li id="gs_cit1" class="gs_citr" tabindex="0">Sackett, D. L., Rosenberg, W. M., Gray, J. M., Haynes, R. B., &amp; Richardson, W. S. (1996). Evidence based medicine: what it is and what it isn't. Bmj, 312(7023), 71-72.</li>
 	<li class="gs_citr" tabindex="0">Sackett D et al. Evidence-Based Medicine: How to Practice and Teach EBM, 2nd edition. Churchill Livingstone, Edinburgh, 2000, p.1</li>
</ol>

Excitability: The ability of a cell to change in membrane conductance as a response to stimulation.

<ul>
 	<li>For example, muscle cells are specialized to react to a change in membrane potential with contraction, where as nerve cells are specialized to propagate a change in membrane potential along there axons and communicate that message to other tissues via neurotransmitters.
</li>
</ul>
<ol>
 	<li>Saladin, K. (2012). Anatomy &amp; Physiology: The unity of form and function. (6th ed.). New York: McGraw-Hill.</li>
</ol>

Excitation threshold: The level that a depolarization must reach for an action potential to occur.
<ul>
 	<li>The excitation threshold is a contributing factor to the "all-or-none" response of muscle and nerves cells to a stimulus.</li>
</ul>

Exercise Progression - Modification of an exercise with the intent of promoting adaptation by increasing demand. This can be accomplished by increasing reps, load, tempo, range of motion, complexity, and/or challenge to an individual's stability.
<ul>
 	<li>Because load, reps, tempo and complexity are often explicitly noted, the term "exercise progression" is most often used throughout Brookbush Institute (BI) content to refer to an exercise, or series of exercises that make it harder to maintain stability with good form.
<ul>
 	<li>Sample Exercise Progression: <a href="https://brentbrookbush.com/vimeo_videos/kneeling-chop-pattern/" target="_blank" rel="noopener">Kneeling Chop</a> to <a href="https://brentbrookbush.com/vimeo_videos/static-standing-chop-pattern/" target="_blank" rel="noopener">Standing Chop</a> to <a href="https://brentbrookbush.com/vimeo_videos/single-leg-chop-pattern/" target="_blank" rel="noopener">Single-leg Chop</a></li>
</ul>
</li>
</ul>

Exercise regression - The opposite of progression; that is, modification of an exercise with the intent of reducing demand. This can be accomplished by decreasing reps, load, tempo, range of motion, complexity, and/or challenge to an individual's stability. Generally, regressions are used to modify an exercise to the client's current level of ability, with the intent of improving form, motor learning and retention.
<ul>
 	<li>Because load, reps, tempo and complexity are often explicitly noted, the term "exercise regression" is most often used throughout Brookbush Institute (BI) content to refer to an exercise or series of exercises that make it easier to maintain stability with good form.
<ul>
 	<li>Sample Exercise Regression: <a href="https://brentbrookbush.com/vimeo_videos/single-leg-chop-pattern/" target="_blank" rel="noopener">Single-leg Chop</a> to <a href="https://brentbrookbush.com/vimeo_videos/static-standing-chop-pattern/" target="_blank" rel="noopener">Standing Chop</a> to <a href="https://brentbrookbush.com/vimeo_videos/kneeling-chop-pattern/" target="_blank" rel="noopener">Kneeling Chop</a></li>
</ul>
</li>
</ul>

Experimental Research - Studies in which the researchers introduce the variable to be studied, with the intent of observing the outcome. This is different than observational research which observes the effect of a variable already present. Many texts also assert that experimental research should include randomization and ideally a control group, as is seen in Randomized Control Trials. Studies in which the variable is introduced by the researchers, but participants are not randomized may be considered Quasi-experimental research.
<ul>
 	<li>In this study by Esformes, the experimental variable was squat depth and the outcome measures observed were various performance measures related to power (1).</li>
</ul>
<ol>
 	<li><a href="https://brookbushinstitute.com/article/back-squat-depth-lower-body-post-activation-potentiation/" target="_blank" rel="noopener">Esformes, J., &amp; Bampouras, T. (2013). Effect of back squat depth on lower-body postactivation potentiation. Journal of Strength and Conditioning Research, 27(11), 2997-3000.</a></li>
</ol>
&nbsp;

Extensibility: The ability of a cell to be stretched or lengthened without damage (1).
<ul>
 	<li>For example, most cells would rupture with even a modest stretch, but muscles can stretch up to 3 times their contracted length.</li>
</ul>
<ol>
 	<li>Saladin, K. (2012). Anatomy &amp; Physiology: The unity of form and function. (6th ed.). New York: McGraw-Hill.</li>
</ol>

False Negative - the proportion of negatives in a group that were assessed incorrectly (assessed as negative when the patient was actually positive)
<ul>
 	<li>Test Results: Although most tests/assessments result in either a positive or negative, the accuracy of a test is dependent on the number  of positives and negatives that are correct. Therefore, when the accuracy of a test is determined, their are 4 possible results, because a positive or negative result could be right (true) or wrong (false).</li>
</ul>

False Positive - the proportion of positives in a group that were assessed incorrectly (assessed as positive when the patient was actually negative)
<ul>
 	<li>Test Results: Although most tests/assessments result in either a positive or negative, the accuracy of a test is dependent on the number  of positives and negatives that are correct. Therefore, when the accuracy of a test is determined, their are 4 possible results, because a positive or negative result could be right (true) or wrong (false).</li>
</ul>

The function of fascia is to transmit force, provide support, and protect tissues. Fascia can effect motion by:
Transmitting force from one or more muscles (example: the thoracolumbar fascia)
Restricting motion in cases of adaptive shortening and/or adhesion to proximal structures (example: iliotibial band in cases of lower-leg dysfunction)
Elastic recoil after stretching can contribute to force production (example: plyometric exercise)

Note: There is evidence that fascia may house more receptors related to human movement than other tissues. In this way fascia may act as a motherboard for the nervous system

The fascial system does not contract or develop trigger points, and its capacity to adapt to stretching and or strengthening exercise is limited, especially when compared to the adaptive capacity of muscle tissue.

Fibromyalgia - A loosely defined diagnosis that is associated with a combination of widespread pain in combination with 2) tenderness at 11 or more of the 18 specific tender point sites. Consideration may also be given to the presence of psychosocial stressors and inflammatory disease in the patients history. Newer research suggests that fibromyalgia may be at least in part due to central sensitization of myofascial pain, often associated with trigger points (1 - 4).
<ol>
 	<li>Wolfe, F. (2018). Fibromyalgia Syndrome and Fibromyalgia Syndrome Criteria: Problems in Definition and Validity. Fibromyalgia Syndrome and Widespread Pain: From Construction to Relevant Recognition.</li>
 	<li>Wolfe, F., Smythe, H. A., Yunus, M. B., Bennett, R. M., Bombardier, C., Goldenberg, D. L., ... &amp; Fam, A. G. (1990). The American College of Rheumatology 1990 criteria for the classification of fibromyalgia. Arthritis &amp; Rheumatism: Official Journal of the American College of Rheumatology, 33(2), 160-172.</li>
 	<li>Alonso-Blanco, C., Fernandez-de-las-Penas, C., Morales-Cabezas, M., Zarco-Moreno, P., Ge, H. Y., &amp; Florez-García, M. (2011). Multiple active myofascial trigger points reproduce the overall spontaneous pain pattern in women with fibromyalgia and are related to widespread mechanical hypersensitivity. The Clinical journal of pain, 27(5), 405-413.</li>
 	<li>Staud, R., Nagel, S., Robinson, M. E., &amp; Price, D. D. (2009). Enhanced central pain processing of fibromyalgia patients is maintained by muscle afferent input: a randomized, double-blind, placebo-controlled study. PAIN®, 145(1-2), 96-104.</li>
</ol>
&nbsp;

Muscles that act to reduce or prevent movement at proximal joints to improve force transmission.
Example: The muscles of the core are important fixators; reducing motion of the spine/trunk to enhance force transmission between the extremities and environment.

An increase in joint stability via compressive forces resulting from muscular contraction and increased tension in fascial structures (1,2).
<ul>
 	<li>This term is most often used in reference to core intrinsic stabilizers, the thoracolumbar fascia and the sacroiliac joint; however, force closure and form closure have been mentioned in the literature referring to other joints.</li>
 	<li>Related term: Form closure</li>
</ul>
<ol>
 	<li>Andry Vleeming, Vert Mooney, Rob Stoeckart. Movement, Stability &amp; Lumbopelvic Pain: <a class="glossaryLink " title="Glossary: Integration" href="https://brentbrookbush.com/glossary/integration/" target="_blank" rel="noopener noreferrer" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Integration&lt;/div&gt;&lt;div class=glossaryItemBody&gt;Making a whole of parts.&lt;br /&gt;&lt;br /&gt;Example, The Brookbush Institute uses an integrative approach to explaining and addressing human movement.&lt;/div&gt;">Integration</a> of Research and Therapy. (c) 2007 Elsevier Limited</li>
 	<li id="gs_cit1" class="gs_citr" tabindex="0">Vleeming, A., Pool-Goudzwaard, A. L., Stoeckart, R., van Wingerden, J. P., &amp; Snijders, C. J. (1995). The Posterior Layer of the Thoracolumbar Fascia| Its Function in Load Transfer From Spine to Legs. Spine, 20(7), 753-758.</li>
</ol>

The relative contribution of joint shape and structure to the stability of a joint (1,2).
<ul>
 	<li>This term is most often used in reference to the "rough" articulating surfaces of the sacroiliac joint and the wedge shape of the sacrum; however, force closure and form closure have been mentioned in the literature referring to other joints.</li>
 	<li>Related term: Force closure</li>
</ul>
<ol>
 	<li>Andry Vleeming, Vert Mooney, Rob Stoeckart. Movement, Stability &amp; Lumbopelvic Pain: <a class="glossaryLink " title="Glossary: Integration" href="https://brentbrookbush.com/glossary/integration/" target="_blank" rel="noopener noreferrer" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Integration&lt;/div&gt;&lt;div class=glossaryItemBody&gt;Making a whole of parts.&lt;br /&gt;&lt;br /&gt;Example, The Brookbush Institute uses an integrative approach to explaining and addressing human movement.&lt;/div&gt;">Integration</a> of Research and Therapy. (c) 2007 Elsevier Limited</li>
 	<li id="gs_cit1" class="gs_citr" tabindex="0">Vleeming, A., Pool-Goudzwaard, A. L., Stoeckart, R., van Wingerden, J. P., &amp; Snijders, C. J. (1995). The Posterior Layer of the Thoracolumbar Fascia| Its Function in Load Transfer From Spine to Legs. Spine, 20(7), 753-758.</li>
</ol>

An arthrokinematic motion - linear motion across a joint surface parallel to the plane of the adjacent joint surface, just as your posterior moves relative to a "slide" in a park.

For example, the glide of facet joint in the spine during spinal flexion and extension, or the posterior glide of the humeral head that must accompany anterior roll to maintain congruence with glenoid fossa during shoulder horizontal adduction.

A plane joint (also called an arthrodial joint, gliding joint or plane articulation) is a synovial joint which allows only gliding movement in the plane of the articular surfaces. The opposed surfaces of the bones are flat or almost flat, with movement generally limited by tight capsules and ligaments. Plane joints are numerous, are most often small, and allow very little motion.  Examples include the carpal joints of the wrist, the tarsal joints of the ankle, and the facet joints of the spine.

"...refers to the measurement of angles, in particular the measurement of angles created at human joints by the bones of the body (1).

&nbsp;
<ol>
 	<li>Cynthia C. Norkin, D. Joyce White. Measurement of Joint Motion: A Guide to Goniometry 3rd Edition. Copyright (C) 2003 by F.A. Davis Company</li>
</ol>

Ground reaction force (GRF) - The force exerted by the ground on the body in contact with it.

For example, when a runner's foot strikes the ground with a force equal to the mass of the individual times their acceleration due to gravity, momentum and muscular exertion, the ground exerts an equal and opposite force on the runner's foot.
<ul>
 	<li>GRF is often measured in research studies using force plates as a means of quantitatively measuring the force generated by an individual.</li>
</ul>

H-Band - Refers to the central zone of a sarcomere that looks lighter under a microscope.  This area of the sarcomere is a lighter portion of the A-band where there is no overlap between the thinner filaments (actin), and the thicker filaments (myosin).
<ul>
 	<li>Example, when a muscle contracts, actin and myosin cross-bridging occurs in the region of the A-band until the H-band is reached where no overlap occurs.</li>
</ul>
<ol>
 	<li>Saladin, K. (2014). Anatomy &amp; physiology: The unity of form and function. McGraw-Hill Higher Education, New York. ISBN: 9780073403717</li>
</ol>

A hinge joint (also called a ginglymus) is a synovial joint in which the articular surfaces fit one another in a way that only permits motion in one plane. Examples include the elbow, the knee (unless considered a condyloid joint) and the interphalangeal joints.

Holism (holistic) (biological holism) - (from Greek holos "all, whole, entire") is the idea that systems and their properties should be viewed as wholes, not just as a collection of parts.
<ul>
 	<li>Summarized by Aristotle in his "Metaphysics": "The whole is more than the sum of its parts". However, the term "holism" was introduced into language by the South African statesman Jan Smuts as recently as 1926. (Smuts J. C. 1987 [1926]. Holism and evolution. Cape Town: N &amp; S Press.)</li>
</ul>
Example: The Brookbush Institute promotes a holistic approach to human movement science, in which the muscular, fascial, articular and neural systems are not viewed as separable and all proximal segments are considered.

Hormone: Chemical messengers produced by the endocrine system, transported via tissue fluids such as blood, to stimulate cells to "act."
<ul>
 	<li>Example: Growth hormone is secreted by the pituitary gland in the brain; stimulating growth, cell reproduction and cell regeneration in certain types of cells</li>
</ul>
The English physician E. H. Starling discovered in collaboration with the physiologist W. M. Bayliss secretin, the first hormone, in 1902. (1).
<ol>
 	<li>Henriksen, J. H., &amp; de Muckadell, O. S. (2000). Secretin, its discovery, and the introduction of the hormone concept. Scandinavian journal of clinical and laboratory investigation, 60(6), 463-472.</li>
</ol>

A range of motion achieved by the patient/client that is more than normal.
<ul>
 	<li>Note: Both hyper-mobility and hypo-mobility may adversely affect motion and may lead to deleterious effects on joints and soft tissue over time. There is no evidence to suggest that more or less flexibility than normal is beneficial.</li>
</ul>
Example: If an individual can place their forehead on their knees they are likely hypermobile at one, if not several joints

Example 2: 110° of shoulder external rotation would be considered hyper-mobile.

Hyperplasia is an increase in organic tissue size due to an adaptive increase in the number of cells per organ.
<ul>
 	<li>Although muscle hyperplasia has been noted in some animals, human muscle tissue does not seem to have this adaptive ability.</li>
</ul>

A condition of excessive tone of the skeletal muscles; increased resistance of muscle to passive stretching.  May be related to increased neural drive, synergistic dominance, trigger points, reflexive over-activity, and/or muscle length.
Example:  Individuals who exhibit ankle eversion and abduction during an overhead squat assessment likely have hypertonic fibularis (peroneal) muscles.

Muscular hypertrophy is an increase in muscle mass/size due to increase in the volume and cross-sectional area (CSA) of individual muscle cells. The increase in cross-sectional area can be attributed to an an increase in contractile proteins and structural elements (myofibrillar hypertophy), as well as an increase in glycogen storage and elements related to metabolism (sarcoplasmic hypertophy). Hypertrophy is an adaptation of both cardiac and skeletal muscle fibers in response to progressive increases in workload.
<ul>
 	<li>Note: Hypertrophy is not hyperplasia. Hyperplasia is an increase in muscle size due to an adaptive increase in the number of muscle fibers/cells per muscle. This type of adaptation does not occur in human muscle tissue.</li>
</ul>

A range of motion achieved by a patient/client that is less than normal.
<ul>
 	<li>Note: Both hyper-mobility and hypo-mobility may adversely affect motion and may lead to deleterious effects on joints and soft tissue over time. There is no evidence to suggest that more or less flexibility than normal is beneficial.</li>
</ul>
Example: If the end range of shoulder external rotation is reached and measured as 75° during goniometric assessment, the client/patient is exhibiting hypomobility of the glenohumeral joint (shoulder).

Hypothesis - a proposed explanation for a phenomenon; "scientific hypotheses" are generally constructed in a way that is testable or falsifiable.
<ul>
 	<li>Example: The hypothesis, "excessive knee valgus may be correlated with future knee pain and injury," has been the subject of several studies published over the last decade.</li>
</ul>

Diminished tone of skeletal muscles; diminished resistance of muscles to passive stretching.   May be related to inhibition, reciprocal inhibition, arthrokinematics inhibition and/or  increased resting length of muscle.
Example:  If your knees cave (hip adduction) during a squat or leg-press it is likely that your gluteus medius is hypotonic.

I-Band - Refers to the part of the muscle cell that looks lighter under a microscope.  This area of the cell is lighter due to parallel arrangement of thinner filaments (actin), and no overlap with the thicker filaments (myosin).
<ul>
 	<li>As a muscle contracts, the I-bands will decrease in width and move closer to one another.</li>
</ul>
<ol>
 	<li>Saladin, K. (2014). Anatomy &amp; physiology: The unity of form and function. McGraw-Hill Higher Education, New York. ISBN: 9780073403717</li>
</ol>

Independent variable - in research, this is the variable or phenomenon being manipulated in the study.
<ul>
 	<li>Example, in the study by Ghanbari et al. (1), the independent variable is "knee joint mobilization", the dependent variable is "quadriceps muscle strength."</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/effect-knee-joint-mobilization-quadriceps-muscle-strength/" target="_blank" rel="noopener noreferrer">Ghanbari A. and Kamalgharibi S. (2013). Effect of knee joint mobilization on quadriceps muscle strength. International Journal of Health and Rehabilitation Sciences. 2(4): 186-191</a></li>
</ol>

An anatomical direction; toward the bottom (below)

Example, the mouth is inferior to the eyes

A reduction in neural drive, muscular activity, and or force output due to altered neuromuscular reflex.  Alterations in neuromuscular reflex may occur due to increases in muscle length (hypothesis: increased excitation threshold), altered reciprocal inhibition in response to increased antagonist tone, and or alterations in joint motion (arthrokinematics inhibition).

Making a whole of parts.

Example, The Brookbush Institute uses an integrative approach to explaining and addressing human movement.

Intermuscular Coordination - Optimal timing and motor unit recruitment of agonists, antagonists, synergists, neutralizers, stabilizers and fixators.

Example: Role of Muscles during Hip Extension
<ul>
 	<li><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Prime Mover" href="https://brentbrookbush.com/glossary/prime-mover/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Prime Mover&lt;/div&gt;The muscle most responsible for a joint action under load -&lt;br /&gt;&lt;br /&gt;That is, the muscle that can produce the most force for a given joint action. Often this term is used synonymously with the term agonist. The prime mover as defined above, may or may not be the most active muscle for a joint action during activities of daily living.&lt;br /&gt;&lt;br /&gt;Example: the gluteus maximus is the most powerful hip extensor and therefore the prime mover; however, the hamstrings are likely the most active hip extensors during low level activities like walking or standing.">Prime Mover</a>:  <a href="https://player.vimeo.com/external/82855344.hd.mp4?s=54c3e7d98fb9d4e0af8d282c85ba9b3e">Gluteus maximus</a></li>
 	<li><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Synergists" href="https://brentbrookbush.com/glossary/synergists/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Synergists&lt;/div&gt;Muscles that assist the prime mover in performing a joint action.&lt;br /&gt;&lt;br /&gt;That is, all muscles that can perform a joint action that are not the prime mover, are termed synergists.&lt;br /&gt;Example: The rectus abdominis is the prime mover of spinal flexion. All other muscles that can perform spinal flexion are synergists including – external obliques, internal obliques and psoas.">Synergists</a>: <a href="https://brentbrookbush.com/articles/muscular-anatomy/biceps-femoris/">Biceps femoris (long head)</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/semitendinosus-and-semimembranosus/">semitendinosus, semimembranosus</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/adductors/">posterior head of adductor magnus</a></li>
 	<li><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Antagonist" href="https://brentbrookbush.com/glossary/antagonists/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Antagonist&lt;/div&gt;Muscles that oppose the prime mover and synergists for a given joint action.&lt;br /&gt;&lt;br /&gt;That is, all the muscles that can perform the opposing joint action.&lt;br /&gt;&lt;br /&gt;Example: The triceps and anconeus are antagonists during elbow flexion.">Antagonists</a>: <a href="https://brentbrookbush.com/articles/muscular-anatomy/psoas/">Psoas</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/iliacus/">iliacus</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/tensor-fascia-latae-tfl/">tensor fascia latae</a> (TFL),<a href="https://brentbrookbush.com/articles/muscular-anatomy/rectus-femoris/"> rectus femoris</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/adductors/">anterior adductors (especially pectineus)</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/sartorius/">sartorius</a></li>
 	<li><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Neutralizer" href="https://brentbrookbush.com/glossary/neutralizers/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Neutralizer&lt;/div&gt;Muscles that oppose unwanted joint motions created by the prime mover and/or synergists, and/or muscles that prevent unwanted ancillary motion.&lt;br /&gt;Example: The teres minor and infraspinatus neutralize the internal rotation force created by the pectoralis major during horizontal adduction of the shoulder.">Neutralizers</a>: <a href="https://brentbrookbush.com/articles/muscular-anatomy/gluteus-minimus/">Gluteus minimus</a> and <a href="https://brentbrookbush.com/articles/muscular-anatomy/gluteus-medius/">anterior fibers of gluteus medius</a> neutralize external rotation force of <a href="https://brentbrookbush.com/articles/muscular-anatomy/gluteus-maximus/">gluteus maximus</a></li>
 	<li><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Stabilizer" href="https://brentbrookbush.com/glossary/stabilizers/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Stabilizer&lt;/div&gt;Muscles whose primary role is to improve arthrokinematics by maintaining optimal alignment of joint surfaces.&lt;br /&gt;&lt;br /&gt;Most often these muscles are the most intrinsic muscles of a joint, have a larger percentage of Type I muscle fibers and are rich in proprioceptors.&lt;br /&gt;Example: The muscles of the rotator cuff act as stabilizers for most shoulder motions.">Stabilizers</a>: <a href="https://brentbrookbush.com/articles/muscular-anatomy/deep-rotators-of-the-hip/">Deep rotators of hip</a></li>
 	<li><a class="glossaryLink " style="box-sizing: border-box; font-family: roboto; color: #000000 !important; font-size: 15px; outline: none; background: transparent; border-bottom: 1px dotted #000000 !important; text-decoration: none;" title="Glossary: Fixator" href="https://brentbrookbush.com/glossary/fixators/" target="_blank" rel="noopener" data-cmtooltip="&lt;div class=glossaryItemTitle&gt;Fixator&lt;/div&gt;Muscles that act to reduce or prevent movement at proximal joints to improve force transmission.&lt;br /&gt;Example: The muscles of the core are important fixators; reducing motion of the spine/trunk to enhance force transmission between the extremities and environment.">Fixators</a>: <a href="https://brentbrookbush.com/articles/core-subsystems/intrinsic-stabilization-subsystem/">Intrinsic stabilization subsystem</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/rectus-abdominis/">rectus abdominis</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/internal-obliques/">internal</a> and <a href="https://brentbrookbush.com/articles/muscular-anatomy/external-obliques/">external obliques</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/quadratus-lumborum/">quadratus lumborum</a>, <a href="https://brentbrookbush.com/articles/muscular-anatomy/erector-spinae/">erector spinae</a></li>
</ul>
&nbsp;

Example from: <a href="https://brentbrookbush.com/articles/anatomy-articles/introduction-to-functional-anatomy/kinesiology-of-the-hip/" target="_blank" rel="noopener">Introduction to Functional Anatomy: Kinesiology of the Hip</a>

Intramuscular coordination refers to the coordinated recruitment of motor units within a single muscle. This concept is used to explain increases in maximal strength and power; however, the coordinated and sequential recruitment of motor units is also essential to strength endurance and smooth coordinated motion.  Related terminology may include; motor unit recruitment, preferential recruitment, rate coding, sequence, etc..

Example: It is hypothesized that the "shaking" noted during a novice exercisers attempt at an activity like the <a href="https://brentbrookbush.com/vimeo_videos/ball-crunch-and-progressions/" target="_blank">stability ball crunch</a> may be due to relatively poor intramuscular coordination. Rather than smooth, sequential firing of rectus abdominis motor units, groups of motor units turn on and off in an uncoordinated manner.

Pertaining to the same side

Example, the quadratus lumborum performs ipsilateral flexion; lateral flexion toward the same side as the muscle.

An isoform, or variant, is a member of a set of similar proteins, that originate from the same gene, or gene family.
<ul>
 	<li>Example, the variations in myosin heavy chain proteins (MHC I, MHC IIA, MHC IIB/X) that contribute to the characteristic differences between muscle fiber types.</li>
</ul>

“The Prime Assumption”
Everything crossing a joint will influence joint motion during every joint action.

A concept that has expanded over the past several decades to describe the integration of 4 body systems (muscle, joints, fascia and nerves), as well as, the coordinated function of various body segments (e.g. hip, knee and ankle) to produce motion. Kinetic referring to motion, and chain being an analogy for the interdependent link between systems.

Example, the posterior kinetic chain, refers to the integrated function of nerves, muscles, fascia and joints on the posterior side of the body.

The concept of the kinetic chain was originally adapted from the work of a mechanical engineer named Franz Reuleaux (Kinematics of Machinery (1875)) by Dr. Arthur Steindler in 1955 (Steindler A: Kinesiology of the Human Body. Springfield, IL, Charles C. Thomas Co.. 1955).

Latent Trigger Point - A myofascial trigger point that is not painful at rest, only painful when palpated, and may or may not exhibit a characteristic referral pain pattern when palpated.  Latent trigger points do result in an acute point of sensitivity, in a taut band of muscle, and may restrict range of motion (1).

Note: Based on the clinical experience, the Brookbush Institute suggests that latent trigger points (sometimes refereed to as Tender Points) are more common than active trigger points. Further, they are likely addressed more often than trigger points; being the intended target of many soft-tissue mobility techniques.
<ol>
 	<li>David G. Simons, Janet Travell, Lois S. Simons, Travell &amp; Simmons’ Myofascial Pain and Dysfunction, The Trigger Point Manual, Volume 1. Upper Half of Body: Second Edition,© 1999 Williams and Wilkens</li>
</ol>

An anatomical direction; further from the midline

Example, the anterior deltoid is lateral to the pectoralis major

Length/Tension Relationship - The amount of force generated by a muscle is dependent on sarcomere length.
<ul>
 	<li>The ability of sarcomere to maximally produce force occurs when sarcomere length results in optimal overlap between actin and myosin. Stretching a sarcomere decreases overlap between actin and myosin filaments and reduces force production (1-3). When length is less than optimal, actin from opposite ends overlap and interfere with cross-bridging, and myosin filament are compressed as they contact the the Z-disk also reducing force (4)</li>
</ul>
<ol>
 	<li>Gordon, A. M., Huxley, A. F., &amp; Julian, F. J. (1966). The variation in isometric tension with sarcomere length in vertebrate muscle fibres. The Journal of physiology, 184(1), 170-192.</li>
 	<li>Edman, K. A. P. (1966). The relation between sarcomere length and active tension in isolated semitendinosus fibres of the frog. The Journal of Physiology, 183(2), 407-417.</li>
 	<li>Lieber, R. L., Loren, G. J., &amp; Friden, J. (1994). In vivo measurement of human wrist extensor muscle sarcomere length changes. Journal of neurophysiology, 71(3), 874-881.</li>
 	<li>Lieber, R. L. (2002). Skeletal muscle structure, function, and plasticity. Lippincott Williams &amp; Wilkins.</li>
</ol>
&nbsp;

Levels of Evidence - Relative to evidence-based practice, levels of evidence are an attempt to describe the strength of the results measured in a clinical trial or research study.  Note: levels of evidence do not supersede the critical evaluation of an experienced professional, and should be viewed as guidelines - a meta-analysis may be poorly constructed (Level IA), and a comparative study (Level III) may employ new technologies and a strong methodology.


The Levels of Evidence used by the Brookbush Institute, as described by Shekelle et al.(1):
<ul>
 	<li class="p1">IA - Evidence from meta-analysis of randomized controlled trials</li>
 	<li class="p1">IB - Evidence from at least one randomized controlled trial</li>
 	<li class="p1">IIA - Evidence from at least one controlled study without randomization</li>
 	<li class="p1">IIB - Evidence from at least one other type of quasi-experimental study</li>
 	<li class="p1">III - Evidence from non-experimental descriptive studies, such as comparative studies, correlation studies, and case-control studies</li>
 	<li class="p1">IV - Evidence from expert committee reports or opinions or clinical experience of respected authorities, or both</li>
</ul>
<ol>
 	<li>Shekelle, P. G., Woolf, S. H., Eccles, M., &amp; Grimshaw, J. (1999). Developing clinical guidelines. Western Journal of Medicine, 170(6), 348.</li>
</ol>

Likelihood Ratios - Likilihood ratios are used for assessing the value of performing a diagnostic test. They use sensitivity and specificity to determine whether a test result usefully changes the practitioner's chance (probability) of reaching the correct assessment. Calculation of likelihood ratios is based on Baye's theorem.
<ul>
 	<li>Positive Likelihood Ratio (LR+) - The ratio of a positive test result in people with the pathology to a positive test result in people without the pathology.</li>
 	<li>Negative Likelihood Ratio (LR-) - The ratio of a negative test result in people with the pathology to a negative test result in people without the pathology.</li>
</ul>

Longitudinal Study - a research design that involves observing the same variables, several times over a period of time.
<ul>
 	<li>Example, the study by Hewett et al. (1) is a type of longitudinal study called a "cohort study." This study investigated whether excessive knee valgus during landing was a predictor of knee injury risk in adolescent females over the course of a season.</li>
</ul>
<ol>
 	<li><a href="https://brentbrookbush.com/articles/research-corner/knee/research-review-increased-valgus-during-landing-predicts-acl-injury-in-adolescent-female-athletes/" target="_blank" rel="noopener noreferrer">Hewett, T. E., Myer, G. D., Ford, K. R., Heidt, R. S., Colosimo, A. J., McLean, S. G., &amp; Succop, P. (2005). Biomechanical measures of neuromuscular control and valgus loading of the knee predict anterior cruciate ligament injury risk in female athletes A prospective study. The American journal of sports medicine, 33(4), 492-501</a></li>
</ol>

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