Sternoclavicular (SC), Acromioclavicular (AC), and Scapulothoracic (ST) Joint Anatomy

This course describes sternoclavicular joint anatomy (SC joint), acromioclavicular joint anatomy (AC Joint), and scapulothoracic joint anatomy (ST joint). These are the joints resulting from the approximation of the sternum (breastbone) with the medial clavicle (collar bone), the distal clavicle with the scapula (shoulder blade), and the scapula with the rib cage. These joints are also referred to as the shoulder girdle, and most often analyzed by referring to motion of the scapula. This course includes descriptions of the bones, synovial joints, joint actions, ligaments, bursae, relative location, the relationship between the bones of the clavicle, sternum, acromion, and thoracic spine, and the muscles that cross them. Further, this course discusses palpation and introduces sternoclavicular, acromioclavicular, and scapulothoracic joint (upper limb) specific exercises, manual techniques, and interventions for dysfunction, pain, posture, and movement impairment. The SC, AC, and ST joints often play a role in common dysfunctions and joint injuries of the shoulder including upper crossed syndrome, rounded shoulder posture, upper body dysfunction (UBD) (e.g. impingement syndrome), cervical spine dysfunction, forward head posture (e.g. chronic neck pain), thoracic spine dysfunction and thoracic kyphosis (e.g. upper back pain), sternocostal dysfunction and stiffness (e.g. costochondritis), and elbow dysfunction (e.g. lateral epicondylitis). Sports medicine professionals (personal trainers, fitness instructors, physical therapists, massage therapists, chiropractors, occupational therapists, athletic trainers, etc.) with advanced knowledge of the sternoclavicular, acromioclavicular, and scapulothoracic joints 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. assessment and treatment of joint injury, joint separation/dislocation, shoulder pain, shoulder separation, rotator cuff injury, type II acromion, ac joint sprain, and upper limb pain), the effect the SC, AC, and ST joints have on upper extremity (upper limb) and cervical spine alignment (e.g. a forward head position), and active and passive exercises for the shoulder girdle, including techniques to enhance sports performance (e.g. upper limb stability, strength, hypertrophy, and power).

Brookbush Institute's most recommended techniques for the SC, AC, and ST joints (see videos below):

• Assess:
  • Acromioclavicular (AC) Joint Cross Body Test
• Self-administered Techniques:
  • Release: Levator Scapulae
  • Stretch: Levator Scapula Static Stretch
  • Activation: Serratus Anterior
• Manual Techniques:
  • Release: Pectoralis Minor
  • Mobilization: Thoracic Spine Mobilization: Posterior-to-Anterior
  • Manipulation: Cervicothoracic Junction Manipulation

Caption: Cross section of the AC joint