Double Check for inclusion in "Reliability":

Gianola, S., Cattrysse, E., Provyn, S., & Van Roy, P. (2015). Reproducibility of the kinematics in rotational high-velocity, low-amplitude thrust of the upper cervical spine: a cadaveric study. Journal of manipulative and physiological therapeutics, 38(1), 51-58.

• Abstract Objective This study aimed to investigate the reproducibility of the kinematics in rotational high-velocity, low-amplitude (HVLA) thrust of the upper cervical spine.Methods Twenty fresh human cervical specimens were studied in a test-retest situation with 2 manual therapists. Kinematics of C1-C2 and C0-C1 were examined during segmental rotational HVLA manipulation through an ultrasound-based tracking system. The thrust moment was analyzed by 3-dimensional aspects: the range of motion of axial rotation, flexion-extension, lateral banding, and the cross-correlation between the axial rotation and the coupled lateral banding components.Results During rotational HVLA thrust on C1-C2, the main axial rotation demonstrates an intraexaminer relationship varying from almost perfect to fair (intraclass correlation coefficient = 0.71; intraclass correlation coefficient = 0.35) and a substantial interexaminer correlation of 0.73.Conclusions This study showed substantial levels of reliability for the main axial rotation component of segmental manual rotational HVLA thrust on C1-C2. Intra- and interrater reliability for flexion-extension, lateral bending, and cross-correlation was low.

Talbott and, N. R., & Witt, D. W. (2016). In vivo measurements of humeral movement during posterior glenohumeral mobilizations. Journal of Manual & Manipulative Therapy, 24(5), 269-276.

Talbott et al. investigated force, motion and reliability during Kaltenborn, AP, shoulder mobilization techniques demonstrating good inter-tester reliability, significant differentiation of force between grades, and total motion of 3.0mm for grade I, 8.2mm for grade II, and 10.7mm for grade III ().

• Objectives The purpose of this study was to quantify in vivo posterior translational movements occurring in the glenohumeral joint during posterior mobilizations and to determine the intratester reliability of those posterior translational movements.Methods Twenty-eight individuals (17 females, 11 males) participated in this study. One physical therapist utilized a Kaltenborn approach to apply three grades of posterior humeral mobilization. A hand held dynamometer was used to quantify the force used during each grade of mobilization. Ultrasound imaging was used to visualize and measure posterior humeral movement. Statistical analysis included descriptive statistics for force and posterior movement, intraclass correlation coefficient (ICC) for intrarater reliability of force and posterior movement during each grade of mobilization and paired t-tests to compare movement and force between grades of mobilization.Results Mean posterior movement (mm) measurements were 3.0, 8.2 and 10.7 for grade I, grade II and grade III mobilizations, respectively. Mean force (Newtons) measurements used during mobilization were 41.7, 121.5 and 209.4 for grade I, grade II and grade III mobilizations, respectively. The ICCs ranged from 0.849 to 0.905 for movement and from 0.717 to 0.889 for force. Force and measurement values were significantly different between grades of mobilization and between dominant and non-dominant arms. Gender was found to be significantly associated with force.Discussion Mean movements and mean forces occurring during posterior mobilization increased with increasing grades. Intratester reliability was high for all grades of manual mobilization supporting the use of subjective feedback to determine appropriate force application. Quantification of forces and movements helps to clarify parameters that can serve as a reference for clinical practice.

Latimer, J., Lee, M., & Adams, R. D. (1998). The effects of high and low loading forces on measured values of lumbar stiffness. Journal of manipulative and physiological therapeutics, 21(3), 157-163.

Latimer et al. demonstrated that differences in the force applied during manual assessment of PA stiffness of the spine resulted in different stiffness values. Moderate reliability was found when using a wider range of forces; however, this study implies that clinicians should be aware that different amounts of PA pressure will result in varied levels of stiffness ().

• Objective One explanation for the poor reliability of manual judgments of posteroanterior (PA) stiffness may be that if manual therapists use different forces when testing, different stiffness is perceived. This study was conducted to examine measurements of lumbar PA stiffness obtained using a device programmed to generate different loading forces. Subjects Twenty-five subjects with no history of low back pain and a mean age of 23.5 yr were measured. Methods Measures of lumbar PA stiffness were obtained using a mechanical device that applied a testing force of 200 N to the skin overlying the L3 spinous process. Six stiffness coefficients were determined from the force/displacement curve obtained from each subject by performing linear regressions from 30-80 N, 30-150 N, 30-200 N, and from 30-83.3 N, 83.3-136.7 N, and 136.7-200 N. Intraclass correlation coefficients and repeated measures analysis of variance were used to analyze the data. Results Although moderate reliability was found for stiffness measures arising from increasingly wide force-interval regressions (30-80 N, 30-150 N, 300-200 N), poor reliability was found for stiffness measures arising from same-width, higher force regressions (30-83.3 N, 83-137 N, 137-200 N). In both cases there were significant differences between the obtained K stiffness values corresponding to different force intervals. Conclusion These results show that if therapists push harder, different stiffnesses will be felt. Studies using instrumental measurement of spinal stiffness to obtain 'K' values should report the force intervals used. Also, revised protocols for manually judging PA stiffness should ensure that stiffness is assessed by sampling specified force intervals rather than the raters determining their own force limits.

Ngan, J. M., Chow, D. H., & Holmes, A. D. (2005). The kinematics and intra-and inter-therapist consistencies of lower cervical rotational manipulation. Medical engineering & physics, 27(5), 395-401.

Ngan et al. investigated kinematic parameters of cervical manipulations performed by 3 therapists on 8 asymptomatic subjects, with 1 therapist performing manipulation on all subjects on 2 separate occasions. Although kinematic parameters between therapists, participants and sessions varied widely, there was a consistent use of de-rotation prior to thrust of a mean 4.8 degrees, head to torso angle was relatively consistent for all practitioners and participants, and technique between therapists was similar ().

• The aim of this study was to determine the in vivo kinematics of cervical rotational manipulation in normal subjects and examine the consistency of this technique within and between therapists. A four camera motion analysis system operating at 120 Hz was used to measure the head on trunk angular displacements during manipulation performed by three therapists on eight subjects. One of the therapists performed the manipulation twice for each subject over separate sessions. A consistent pattern of de-rotation prior to thrust was found with little motion other than axial rotation during de-rotation and thrust. The pooled mean de-rotation displacement was 4.8 degrees and the pooled mean thrust angle was 11.3 degrees , but these varied widely, and none of the kinematic parameters recorded proved to be consistent within or between therapists. Most of the kinematic parameters were correlated with the exception of thrust duration. Qualitative analysis shows a consistent technique in cervical rotational manipulation. Pre-manipulation positioning of the head relative to the trunk was fairly consistent for a single therapist over separate sessions, but other than this, the kinematic parameters in cervical rotational manipulation are generally inconsistent within and between therapists.

Introduction to Joint Mobilizations and Manipulations

By Brent Brookbush DPT, PT, COMT, MS, PES, CES, CSCS, ACSM H/FS

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Definitions

• Mobilizations
• Manipulations
• Grades

Types of mobilizations

• AP
• PA
• UPA
• CPA
• Transverse

Protocols

• Cyriax/Maitland
• Kaltenborn
• Stanley Paris
• Mulligan
• Cyriax
• McKenzie
• NAIOMPT
• Osteopathic

Experience Makes a Difference

Descarreaux, M., Dugas, C., Treboz, J., Cheron, C., & Nougarou, F. (2015). Learning spinal manipulation: the effect of expertise on transfer capability. Journal of Manipulative and Physiological Therapeutics, 38(4), 269-274.

Descarreaux et al. demonstrated that expertise and performance conditions modulated biomechanical parameters during spinal manipulation, including increased variability in students (5th and 6th year) and when performing manipulations in less than ideal environments (table too high, table less stable). Generally, trainees and experts choose to modulate force to optimize thrust duration in less than ideal conditions.

• Results Results indicated that both expertise and performance conditions modulated the biomechanical parameters of spinal manipulation. Decreased thrust duration and increased rate of force application were observed in experienced clinicians, whereas thrust force and thrust rate of force application were significantly decreased when task difficulty was increased. Increasing task difficulty also led to significant increases in performance variability.Conclusion Overall, this study suggests that when instructed to perform spinal manipulation in a challenging context, trainees and experts choose to modulate force to optimize thrust duration, a characteristic feature of high-velocity, low-amplitude spinal manipulation. Given its known association with motor proficiency, transfer capability assessments should be considered in spinal manipulative therapy training.
• Objective Transfer capability represents the changes in performance in one task that result from practice or experience in other related tasks. Increased transfer capability has been associated with expertise in several motor tasks. The purpose of this study was to investigate if expertise in spinal manipulation therapy, assessed in groups of trainees and experienced chiropractors, is associated with increased transfer capabilities.Methods Forty-nine chiropractic students (fifth- and sixth-year students) and experienced chiropractors were asked to perform blocks of 10 thoracic spine manipulations in 3 different conditions: preferred position and table setting, increased table height, and unstable support surface. Spinal manipulations were performed on a computer-connected device developed to emulate a prone thoracic spine manipulation. Thrust duration, thrust force rate of force application, and preload force were obtained for each trial and compared across groups and conditions.Results Results indicated that both expertise and performance conditions modulated the biomechanical parameters of spinal manipulation. Decreased thrust duration and increased rate of force application were observed in experienced clinicians, whereas thrust force and thrust rate of force application were significantly decreased when task difficulty was increased. Increasing task difficulty also led to significant increases in performance variability.Conclusion Overall, this study suggests that when instructed to perform spinal manipulation in a challenging context, trainees and experts choose to modulate force to optimize thrust duration, a characteristic feature of high-velocity, low-amplitude spinal manipulation. Given its known association with motor proficiency, transfer capability assessments should be considered in spinal manipulative therapy training.

Triano, J. J., Gissler, T., Forgie, M., & Milwid, D. (2011). Maturation in rate of high-velocity, low-amplitude force development. Journal of manipulative and physiological therapeutics, 34(3), 173-180.

Triano et al. demonstrated a maturation of manipulation skill over 5 years of chiropractic schooling, including statistically significant increase in force rate, decreased rise time, and decreased peak force. With peak force improving most in years 2 - 3, and a reduction in change years 4 - 5 ().

• Abstract Objectives The purpose of this study was to examine the maturation of force development during a thoracic high-velocity, low-amplitude displacement procedure at stages throughout chiropractic education. The hypothesis posed a natural development in rate of force directly related to the duration of experience. The analysis sought to define interrelationships between key characteristics within the procedure.Methods Fifty volunteers (17 women and 33 men) from a Canadian chiropractic college participated in this study. Participants were block randomized into 5 cohorts of 10 subjects, representing years 1 to 4 and graduates with more than 5 years of practice experience. Participants performed a hypothenar transverse push procedure on the upper thoracic spine, with the subjects lying on a force-sensing table. The average of 3 force-time profiles of the procedures was compared across cohorts using analysis of variance for differences between groups, and pairwise comparisons by Scheffé test, using Holms method for P value adjustment.Results Peak force, force rate, and rise time revealed strong differences based on cohort (P < .001). A natural maturation in high-velocity, low-amplitude force development occurs during training. Little change in peak force occurs in the first 2 years. The majority of development occurs in year 3, with tapering through year 4. A reciprocal coupling exists between peak force and force rate.Conclusions Group means revealed statistically significant and monotonic increase in force rate, a decreased rise time, and decreased peak force during delivery of the therapeutic peak force. These differences paralleled growth in experience but with an asymptotic leveling of change between the fourth year of training and 5 years of clinical practice experience. This study showed a systematic maturation in performance associated with educational experience. The reciprocal coupling between rate of force development and peak force created a relatively stable impulse.

Descarreaux, M., Dugas, C., Raymond, J., & Normand, M. C. (2005). Kinetic analysis of expertise in spinal manipulative therapy using an instrumented manikin. Journal of chiropractic medicine, 4(2), 53-60.

Descarreaux et al. compared students and chiropractors performing thoracic spine manipulations on an instrumented manakin based on various force parameters. No group differences were noted for peak force, peak force variability and preload force; however, chiropractors did exhibit less time to peak force, less time to peak force variability, less hand-body delay, greater rate of force production, and faster unloading times ().

• Objective The goals of this study were to measure the kinetic profile of thrust in different groups of subjects with various levels of expertise and to quantify general coordination while performing thoracic spine manipulation.Participants A total of 43 students and chiropractors from the Chiropractic Department of the Université du Québec à Trois-Rivières participated in this study.Methods Participants were asked to complete ten consecutive thoracic spine manipulations on an instrumented manikin. Peak force, preload force, time to peak force, time to peak force variability, peak force variability, rate of force production and unloading time were compared between groups. Hand-body delay obtained by calculating the temporal lag between the onset of unloading and the onset of peak force application was also compared between groups.Results No group difference was observed for the peak force, peak force variability and preload force variables. However, group differences were present for variables like time to peak force, time to peak force variability, rate of force production, unloading time and hand-body delay.Conclusion This study demonstrates clear differences between groups of subjects with different levels of expertise in thoracic spine manipulation. This study also demonstrates the usefulness of a simple, instrumented manikin to analyze spinal manipulation and identify important parameters related to expertise.

Cohen, E., Triano, J. J., McGregor, M., & Papakyriakou, M. (1995). Biomechanical performance of spinal manipulation therapy by newly trained vs. practicing providers: does experience transfer to unfamiliar procedures?. Journal of manipulative and physiological therapeutics, 18(6), 347-352.

Cohen et al. compared preload force, rise rate of thrust, and thrust force of novice and experienced practitioners performing a randomly selected technique that was familiar, but not commonly used by all participants; further, random selection also determined whether experienced or novice participants would be the first to manipulate or have the manipulation done on them. Although values for all measures were consistently higher for experienced manipulators, the difference between participants did not reach statistical significance (). This study suggests that consistent practice of a technique is necessary to optimize technique.

• Objective To examine the differences in predefined biomechanical parameters of spinal manipulation using a single method common to the training of both novice and expert manipulators. Design Analytic Cohort Study. Participants Fifteen novice manipulators and fifteen experienced physicians provided 2 applications of spinal manipulation therapy (SMT) to 15 healthy, male student volunteers. Assignment of volunteers was randomized, and the order of the first interaction with the manipulators was determined by coin toss and then inverted for the second. Intervention The bilateral transverse-thenar thoracic maneuver was selected from the diversified system of treatment to be used as the test procedure. Selection was guided by mechanical simplicity. SMT was applied at the physician's discretion to the region of T3-T10. Standard informed consent procedures were followed. Main outcome measures Preload force, rise rate of thrust and thrust force were selected as prospective primary outcome measures. Secondary descriptive measures included impulse, rise time, downward incisural point (DIP), fall time, total force, force components and direction cosines. Results Both novice and experienced manipulators were familiar with the transverse-thenar procedure, but only three of the experienced manipulators professed common use of it. Mean values for primary outcomes were all higher for the experienced participants; however, no statistically significant differences were found. Discussion Differences are presumed to exist between novice and experienced manipulators, as evidenced by measurement of arbitrarily selected thoracic and lumbar SMT. However, no systematic differences were found when the manipulators have a similar lack of practice experience specific to the test procedure. These results suggest the importance of regular use in developing skill of performance.

Systemic Effects

• Wright, A. (1995). Hypoalgesia post-manipulative therapy: a review of a potential neurophysiological mechanism. Manual therapy, 1(1), 11-16.
  • Search bibliography
• Bolton, P. S., & Budgell, B. S. (2006). Spinal manipulation and spinal mobilization influence different axial sensory beds. Medical hypotheses, 66(2), 258-262.
• Cao, D. Y., Reed, W. R., Long, C. R., Kawchuk, G. N., & Pickar, J. G. (2013). Effects of thrust amplitude and duration of high-velocity, low-amplitude spinal manipulation on lumbar muscle spindle responses to vertebral position and movement. Journal of manipulative and physiological therapeutics, 36(2), 68-77.
• Avramov, A. I., Cavanaugh, J. M., Ozaktay, C. A., Getchell, T. V., & King, A. I. (1992). The effects of controlled mechanical loading on group-II, III, and IV afferent units from the lumbar facet joint and surrounding tissue. An in vitro study. The Journal of bone and joint surgery. American volume, 74(10), 1464-1471.

Mobilization versus Manipulation

Risk of Adverse Effects

• Haldeman, S., Carey, P., Townsend, M., & Papadopoulos, C. (2002). Clinical perceptions of the risk of vertebral artery dissection after cervical manipulation: the effect of referral bias. The Spine Journal, 2(5), 334-342.
• Hufnagel, A., Hammers, A., Schönle, P. W., Böhm, K. D., & Leonhardt, G. (1999). Stroke following chiropractic manipulation of the cervical spine. Journal of Neurology, 246(8), 683-688.
• Oliphant, D. (2004). Safety of spinal manipulation in the treatment of lumbar disk herniations: a systematic review and risk assessment. Journal of Manipulative and Physiological Therapeutics, 27(3), 197-210.
• Quesnele, J. J., Triano, J. J., Noseworthy, M. D., & Wells, G. D. (2014). Changes in vertebral artery blood flow following various head positions and cervical spine manipulation. Journal of manipulative and physiological therapeutics, 37(1), 22-31.
• Rubinstein, S. M. (2008). Adverse events following chiropractic care for subjects with neck or low-back pain: do the benefits outweigh the risks?. Journal of manipulative and physiological therapeutics, 31(6), 461-464.

Triano, J., & Schultz, A. B. (1997). Loads transmitted during lumbosacral spinal manipulative therapy. Spine, 22(17), 1955-1964.

Triano et al. investigated forces from 3 lumbar manipulation techniques on 11 healthy volunteers, using computer modeling to estimate the amount of force through vertebral structures. Findings suggest that the the practitioner may alter the amount of force by changing the technique, intent, posture or speed. The forces recorded resulted in a model that was more complex than originally assumed. The researchers suggested an analogy to the forces experienced by airline baggage handler were experienced during manipulation ().

Effects on the spine were comparable with those encountered by airline baggage handlers, with 92% of men and 83% of women estimated to be of sufficient strength to sustain them. None of the volunteers experienced any discomfort or complications as a result of the tests.

Long-term Efficacy (pull from carousel)

Better than Exercise (pull from carousel)

Compared and Combined with other Interventions

• Effects of patient educaton on mobilization outcomes

Posture

• Assendelft, W. J., Bouter, L. M., & Knipschild, P. G. (1996). Complications of spinal manipulation. J Fam pract, 42(5), 475-80.

Effect of Patient Education

Riley, S. P., Cote, M. P., Leger, R. R., Swanson, B. T., Tafuto, V., Sizer, P. S., & Brismée, J. M. (2015). Short-term effects of thoracic spinal manipulations and message conveyed by clinicians to patients with musculoskeletal shoulder symptoms: a randomized clinical trial. Journal of Manual & Manipulative Therapy, 23(1), 3-11.

An RCT by Riley et al. compared outcomes following treatment for shoulder pain with manipulations or home exercise, following a neutral or positive educational message about manipulations. All groups improved similarly following the intervention, suggesting the tone of the message has little effect on outcomes ().

• Abstract Study design:Randomized clinical trial.Objectives:To evaluate the effects of high-velocity, low-amplitude thrust manipulations (HVLATMs) and various messages on patients with musculoskeletal shoulder symptoms.Background:Previous studies indicated that HVLATM directed at the thoracic spine and ribs resulted in improvements of shoulder range of motion, pain, and disability in patients with musculoskeletal shoulder symptoms. These studies did not explore if the outcome was dependent on thrust location, clinician communication with the patient, or if there were any lasting effects.Methods:A consecutive sample of 100 patients with shoulder pain was randomized into four groups. Patients received one intervention session including: six thoracic HVLATM (spine versus scapula), a message about HVLATM (neutral versus positive), and standardized home exercises. Outcome measures included shoulder Numeric Pain Rating Scale (NPRS), NPRS with impingement testing, and Shoulder Pain and Disability Index (SPADI). Measurements were recorded prior to intervention, immediately following intervention, and at short-term follow-up. Kruskal–Wallis statistics were used for between-group comparisons and Wilcoxon signed ranks for within-group comparisons.Results:Eighty-eight patients (22 per group) completed the study. Statistically significant differences were found for within-group comparisons for most time points assessed. No statistical differences were found for between-group comparisons.Conclusion:Patients improved following the interventions. Neither the type of HVLATM nor the message conveyed to the patients had a significant effect on the patients’ improvements.

Search Bibliography

Pasquier, M., Barbier-Cazorla, F., Audo, Y., Descarreaux, M., & Lardon, A. (2019). Learning spinal manipulation: Gender and expertise differences in biomechanical parameters, accuracy, and variability. Journal of Chiropractic Education, 33(1), 1-7.

• Searched

Triano JJ, Descarreaux M, Dugas C. Biomechanics–review of approaches for performance training in spinal manipulation. J Electromyogr Kinesiol. 2012;22(5):732–739.

Downie AS, Vemulpad S, Bull PW. Quantifying the high-velocity, low-amplitude spinal manipulative thrust: a systematic review. J Manipulative Physiol Ther. 2010;33(7):542–553.

• Bibliography Searched (Maybe helpful for kinematics)

Prevalence of Use:

Rhon, D., Greenlee, T., & Fritz, J. (2018). Utilization of manipulative treatment for spine and shoulder conditions between different medical providers in a large military hospital. Archives of physical medicine and rehabilitation, 99(1), 72-81.

Rhon et al. surveyed 7566 patients from 2014 - 2018, demonstrating that only 26.6 received manipulations as part of treatment, and further, manipulations were used most often for thoracic issues (50.8%) and least often for shoulder issues (24.2%) ().

• Results - Of 7566 total patients seeking care, 2014 (26.6%) received manipulative treatment at least once, and 1870 of those received this treatment in a military facility (24.7%). Manipulative treatment was used most often for thoracic conditions and least often for shoulder conditions (50.8% and 24.2% of all patients). There was a total of 6706 unique medical visits with a manipulative treatment procedure (average of 3.3 manipulative treatment procedure visits per patient).
• Conclusions - Manipulative treatment utilization rates for shoulder and spine conditions ranged from 26.6% to 50.2%. Chiropractors  used manipulation the most and physical therapists  the least..

Thumb Pain

Snodgrass, S. J., Rivett, D. A., Chiarelli, P., Bates, A. M., & Rowe, L. J. (2003). Factors related to thumb pain in physiotherapists. Australian Journal of Physiotherapy, 49(4), 243-250.

Snodgrass et al. investigated potential causes for thumb pain among physical therapists, noting a slightly higher prevalence of osteoarthritis (22.7%) in consideration of the mean age of the particpants (38.6 years). Further, the pain Group reported that their thumb pain was related to and initially caused by the performance of manual techniques, and 88% had altered their manual techniques because of pain in the thumb. There was high variability in hand position and force applied during mobilizations; however, statistically significant differences for the pain group included increased right carpometacarpal joint laxity, decreased right tip pinch strength, and lower body mass index, for the pain group ()

• The aim of this study was to determine whether differences exist between physiotherapists with work-related thumb pain and physiotherapists without thumb pain. Twenty-four physiotherapists with work-related thumb pain (Pain Group) and 20 physiotherapists without thumb or wrist pain (Non-pain Group), who were working at least 20 hours per week in an outpatient musculoskeletal setting, were compared on a number of attributes: generalised joint laxity, hand and thumb strength, height, weight, working environment, hand position and force applied during mobilisation, mobility at individual thumb joints, extent of osteoarthritis at the thumb and radial-sided wrist joints, and demographic data including age, gender and years of experience. All physiotherapists in the Pain Group reported their thumb pain was related to and initially caused by the performance of manual techniques, and 88% had altered their manual techniques because of pain in the thumb. There was extreme variability in hand position and force applied during mobilisation, and a slightly high prevalence of osteoarthritis (22.7%) considering the mean age of the total sample (38.6 years). Statistically significant differences between groups included increased right carpometacarpal joint laxity (6.4%, 95% CI 0.19 to 12.6), decreased right tip pinch strength (0.84 kg, 95% CI 0.01 to 1.68), and lower body mass index (2.0, 95% CI 0.11 to 3.9) for the Pain Group. Other factors were not statistically different between groups. These results indicate that work-related thumb pain affects physiotherapists' ability to administer manual treatments, and suggest that decreased stability and strength of the thumb may be associated with work-related thumb pain.

Kinematics

Moved to Kinematics Post

Learning

Moved to Learning Post

Hyperalgesia

Villafañe, J. H., Silva, G. B., Diaz-Parreño, S. A., & Fernandez-Carnero, J. (2011). Hypoalgesic and motor effects of kaltenborn mobilization on elderly patients with secondary thumb carpometacarpal osteoarthritis: a randomized controlled trial. Journal of manipulative and physiological therapeutics, 34(8), 547-556.

An RCT by Villafane et al. demonstrated that treatment of OA in elderly individuals with 6 sessions (2 weeks) of Kaltenborn mobilizations for the carpometacarpal (CMC) joint of the thumb resulted in a significant reduction in pain pressure sensitivity over the CMC and scaphoid, but did not change tripod pinch strength ().

• Objective This study evaluated the effects of Kaltenborn manual therapy on sensory and motor function in elderly patients with secondary carpometacarpal osteoarthritis (CMC OA).
• Method Twenty-nine female patients with secondary CMC OA (70-90 years old) were randomized into Kaltenborn manual therapy and sham groups. This study was designed as a double-blind, randomized controlled trial (RCT). Therapy consisted of Kaltenborn mobilization of posterior-anterior gliding with distraction in grade 3 of the carpometacarpal (CMC) joint of the dominant hand during 6 sessions over 2 weeks. Pain was measured by algometry, as the pressure pain threshold (PPT) at the CMC joint and tubercle of the scaphoid bone. The tip and tripod pinch strength was also measured. Grip strength was measured by a grip dynamometer. Measurements were taken before treatment and after 1 week (first follow-up ) and 2 weeks (second FU).
• Results All values in the sham group remained unchanged during the treatment period. In the treated group, the PPT in the CMC joint was 2.98 ± 0.30 kg/cm2, which increased after treatment to 4.07 ± 0.53, and was maintained at the same level during the first FU (3.46 ± 0.31) and second FU (3.84 ± 0.36). Similarly, the PPT in the scaphoid bone was 3.61 ± 0.29 kg/cm2, which increased after treatment to 4.87 ± 0.37, and was maintained at the same level during the first FU (4.44 ± 0.43) and second FU (4.22 ± 0.32). In contrast, we found no differences in the tip, tripod pinch, and grip strength measurements between the treatment and sham groups.
• Conclusions This study showed that Kaltenborn manual therapy decreased pain in the CMC joint and scaphoid bone areas of elderly female patients; however, it did not confer an increase in motor function in patients with CMC OA.

Cavitation

(used in kinematics) Van Geyt, B., Dugailly, P. M., Klein, P., Lepers, Y., Beyer, B., & Feipel, V. (2017). Assessment of in vivo 3D kinematics of cervical spine manipulation: Influence of practitioner experience and occurrence of cavitation noise. Musculoskeletal Science and Practice, 28, 18-24.

Van Geyt et al. demonstrated that cervical manipulation magnitude did not exceed active ROM; further, cavitation occurrence was correlated with frontal plane ROM, velocity, sagittal acceleration and practitioner experience.

• Background Investigations on 3D kinematics during spinal manipulation are widely reported for assessing motion data, task reliability and clinical effects. However the link between cavitation occurrence and specific kinematics remains questionable.Objectives This paper investigates the 3D head-trunk kinematics during high velocity low amplitude (HVLA) manipulation for different practitioners with respect to the occurrence of cavitation.Methods Head-trunk 3D motions were sampled during HVLA manipulation in twenty asymptomatic volunteers manipulated by four practitioners with different seniority (years of experience). Four target levels were selected, C3 and C5 on each side, and were randomly allocated to the different practitioners. The data was recorded before, during and after each set of trial in each anatomical plane. The number of trials with cavitation occurrence was collected for each practitioner.Results The manipulation task was performed using extension, ipsilateral side bending and contra-lateral axial rotation independent of side or target level. The displayed angular motion magnitudes did not exceed normal active ROM. Regardless cavitation occurrence, wide variations were observed between practitioners, especially in terms of velocity and acceleration. Cavitation occurrence was related to several kinematics features (i.e. frontal ROM and velocity, sagittal acceleration) and practitioner experience. In addition, multilevel cavitation was observed regularly.Conclusions Kinematics of cervical manipulation is dependent on practitioner and years of experience. Cavitation occurrence could be related to particular kinematics features. These aspects should be further investigated in order to improve teaching and learning of cervical manipulation technique.

Frantzis, E., Druelle, P., Ross, K., & McGill, S. (2015). The accuracy of osteopathic manipulations of the lumbar Spine: A Pilot study. International Journal of Osteopathic Medicine, 18(1), 33-39.

Frantzis et al. investigated the accuracy of lumbar manipulations based on cavitation location using accelerometers, demonstrating cavitations were recorded in 12 of 20 subjects (60%), 16 of the 38 manipulations performed produced at least one cavitation, 8 of 16 cavitations were accurate to the intended target (50%), and the mean variance from the site intended site of cavitation was 5.31 cm. Regression analysis revealed no statistically significant relationship between the site of cavitation and intended target ().

• Objective To assess the segmental specificity, or accuracy, of osteopathic lumbar spinal manipulations.Background Prior studies of chiropractic technique of manual manipulations of the spine designed to target abnormal tissue have been shown to be inaccurate, resulting in adjustments of segments other than the targeted level. This can result in manipulations of areas other than the level of interest of a therapist.Methods Cross-sectional investigation of a convenience sample. Twenty subjects, 14 males and 6 females (mean age = 31.2 years), participated. Eighteen subjects received 2 manipulations and 2 subjects received 3 manipulations that were performed by an experienced osteopath, totalling 42 manipulations. If present, cavitations were recorded using accelerometers from which, quantifying the time to target, revealed the source location. The osteopath and subjects were also asked to report their perception regarding any “clicking” (signifying a cavitation) during manipulations.Results In 12 of the 20 subjects (60%) there was at least one cavitation recorded. Sixteen of the 38 recorded manipulations produced at least one cavitation. Eight (50%) of these were accurate to the intended target. The mean distance between the site of cavitation and the intended target (error) was 5.31 cm. Regression analysis revealed no statistically significant relationship between the site of cavitation and intended target (p = 0.718). There was an increased number of attempts to adjust upper lumbar segments (L1, L2) compared to lower segments (L3, L4); however, there was error inferior to the target segment for 18 of the 23 cavitations (78%).Conclusions These results suggest that osteopathic techniques employed in this study were no different in terms of accurately directing treatment to a specified spinal segment (the mean error was 1 segment away from the intended target segment) than those previously observed using chiropractic techniques.

Van Geyt, B., Dugailly, P. M., Klein, P., Lepers, Y., Beyer, B., & Feipel, V. (2017). Assessment of in vivo 3D kinematics of cervical spine manipulation: Influence of practitioner experience and occurrence of cavitation noise. Musculoskeletal Science and Practice, 28, 18-24.

Frantzis, E., Druelle, P., Ross, K., & McGill, S. (2015). The accuracy of osteopathic manipulations of the lumbar Spine: A Pilot study. International Journal of Osteopathic Medicine, 18(1), 33-39.

Frantzis et al. investigated the accuracy of lumbar manipulations based on cavitation location using accelerometers, demonstrating cavitations were recorded in 12 of 20 subjects (60%), 16 of the 38 manipulations performed produced at least one cavitation, 8 of 16 cavitations were accurate to the intended target (50%), and the mean variance from the site intended site of cavitation was 5.31 cm. Regression analysis revealed no statistically significant relationship between the site of cavitation and intended target ().

• Objective To assess the segmental specificity, or accuracy, of osteopathic lumbar spinal manipulations.Background Prior studies of chiropractic technique of manual manipulations of the spine designed to target abnormal tissue have been shown to be inaccurate, resulting in adjustments of segments other than the targeted level. This can result in manipulations of areas other than the level of interest of a therapist.Methods Cross-sectional investigation of a convenience sample. Twenty subjects, 14 males and 6 females (mean age = 31.2 years), participated. Eighteen subjects received 2 manipulations and 2 subjects received 3 manipulations that were performed by an experienced osteopath, totalling 42 manipulations. If present, cavitations were recorded using accelerometers from which, quantifying the time to target, revealed the source location. The osteopath and subjects were also asked to report their perception regarding any “clicking” (signifying a cavitation) during manipulations.Results In 12 of the 20 subjects (60%) there was at least one cavitation recorded. Sixteen of the 38 recorded manipulations produced at least one cavitation. Eight (50%) of these were accurate to the intended target. The mean distance between the site of cavitation and the intended target (error) was 5.31 cm. Regression analysis revealed no statistically significant relationship between the site of cavitation and intended target (p = 0.718). There was an increased number of attempts to adjust upper lumbar segments (L1, L2) compared to lower segments (L3, L4); however, there was error inferior to the target segment for 18 of the 23 cavitations (78%).Conclusions These results suggest that osteopathic techniques employed in this study were no different in terms of accurately directing treatment to a specified spinal segment (the mean error was 1 segment away from the intended target segment) than those previously observed using chiropractic techniques.

Fryer, G. A., Mudge, J. M., & McLaughlin, P. A. (2002). The effect of talocrural joint manipulation on range of motion at the ankle. Journal of manipulative and Physiological Therapeutics, 25(6), 384-390.

Fryer et al. demonstrated that a single ankle joint manipulation did not increase dorsiflexion range of motion (ROM) in healthy asymptomatic individuals, and further, that ankles that were more mobile prior to manipulation were more likely to cavitate ().

• Objective: To determine whether a single high-velocity, low-amplitude thrust manipulation to the talocrural joint altered ankle range of motion. Design: A randomized, controlled and blinded study. Subjects: Asymptomatic male and female volunteers (N = 41). Methods: Subjects were randomly assigned into either an experimental group (n = 20) or a control group (n = 21). Both ankles of subjects in the experimental group were manipulated by using a single high-velocity, low-amplitude thrust to the talocruraljoint. Pretest and posttest measurements of passive dorsiflexion range of motion were taken. Results: No significant changes in dorsiflexion range of motion were detected between manipulated ankles and those of control subjects. A significantly greater pretest dorsiflexion range of motion existed in those ankles in which manipulation produced an audible cavitation. Conclusion: Manipulation of the ankle does not increase dorsiflexion range of motion in asymptomatic subjects. Ankles that displayed a greater pretest range of dorsiflexion were more likely to cavitate, raising the possibility that ligament laxity may be associated with the tendency for ankles to cavitate. (J Manipulative Physiol Ther 2002;25:384-90)

Andersen, S., Fryer, G. A., & McLaughlin, P. (2003). The effect of talo-crural joint manipulation on range of motion at the ankle joint in subjects with a history of ankle injury. Australasian Chiropractic & Osteopathy, 11(2), 57.

An RCT by Anderson et al. demonstrated that individuals with a history of lateral ligament sprain did not exhibit an increase in dorsiflexion following a single session of ankle manipulation, and further, an insignificant trend was noted of more mobile ankles being more likely to cavitate and exhibit some improvements in ROM ().

• Introduction: There is little research available on the effects of peripheral joint manipulation. Only a few studies have examined the effect of manipulation on ankle range of motion, with conflicting results. This study aimed to determine whether a single high-velocity, low-amplitude (HVLA) thrust manipulation to the talo-crural joint altered ankle range of motion in subjects with a history of lateral ligament sprain.Methods: Male and female volunteers (N=52) with a history of lateral ligament sprain were randomly assigned into either an experimental group (n=26) or a control group (n=26). Those in the experimental group received a single HVLA thrust to the talo-crural joint, whilst those in the control group received no treatment intervention. Pre-test and post-test measurements of passive dorsiflexion range of motion were taken.Results: No significant changes in dorsiflexion range of motion were detected between manipulated ankles and those of control subjects using dependent and independent t-tests. Ankles that cavitated displayed a greater mean DFR and large effect size (d=0.8) compared to those that did not gap and cavitate, but analysis with ANOVA revealed these differences to be not significant.Conclusion: HVLA manipulation of the ankle did not increase dorsiflexion range of motion in subjects with a history of lateral ligament sprain.

Cramer, G. D., Ross, J. K., Raju, P. K., Cambron, J. A., Dexheimer, J. M., Bora, P., … & Habeck, A. R. (2011). Distribution of cavitations as identified with accelerometry during lumbar spinal manipulation. Journal of manipulative and physiological therapeutics, 34(9), 572-583.

Cramer et al. demonstrated that two lumbar side-lying manipulations in quick succession performed by an experienced chiropractor resulted in most cavitations (93.5%) occurring on the upside and in the target area (71.7%), and several joints cavitated multiple times. As was expected, manipulated participants cavitated far more often than those in side-lying positioning (96.7% vs 30%) ().

• Fifty-six cavitations were recorded from 46 joints of 40 subjects. Eight joints cavitated more than once. Group 1 joints cavitated more than group 2 joints (P < .0001), upside joints cavitated more than downside joints (P < .0001), and joints inside the target area cavitated more than those outside the target area (P < .01).Conclusions Most cavitations (93.5%) occurred on the upside of SMT subjects in segments within the target area (71.7%). As expected, SMT subjects cavitated more frequently than did subjects with side-posture positioning only (96.7% vs 30%). Multiple cavitations from the same Z joints had not been previously reported.
• Objective This project determined the location and distribution of cavitations (producing vibrations and audible sounds) in the lumbar zygapophyseal (Z) joints that were targeted by spinal manipulative therapy (SMT).Methods This randomized, controlled, clinical study assessed 40 healthy subjects (20 men, 20 women) 18 to 30 years of age who were block randomized into SMT (group 1, n = 30) or side-posture positioning only (group 2; control, n = 10) groups. Nine accelerometers were placed on each patient (7 on spinous processes/sacral tubercles of L1-S2 and 2 placed 3 cm left and right lateral to the L4/L5 interspinous space). Accelerometer recordings were made during side-posture positioning (groups 1 and 2) and SMT (group 1 only). The SMT was delivered by a chiropractic physician with 19 years of practice experience and included 2 high-velocity, low-amplitude thrusts delivered in rapid succession. Comparisons using χ2 or McNemar test were made between number of joints cavitating from group 1 vs group 2, upside (contact side for SMT) vs downside, and Z joints within the target area (L3/L4, L4L5, L5/S1) vs outside the target area (L1/L2, L2/L3, sacroiliac).Results Fifty-six cavitations were recorded from 46 joints of 40 subjects. Eight joints cavitated more than once. Group 1 joints cavitated more than group 2 joints (P < .0001), upside joints cavitated more than downside joints (P < .0001), and joints inside the target area cavitated more than those outside the target area (P < .01).Conclusions Most cavitations (93.5%) occurred on the upside of SMT subjects in segments within the target area (71.7%). As expected, SMT subjects cavitated more frequently than did subjects with side-posture positioning only (96.7% vs 30%). Multiple cavitations from the same Z joints had not been previously reported.

Cramer, G. D., Ross, K., Raju, P. K., Cambron, J., Cantu, J. A., Bora, P., … & Pocius, J. D. (2012). Quantification of cavitation and gapping of lumbar zygapophyseal joints during spinal manipulative therapy. Journal of manipulative and physiological therapeutics, 35(8), 614-621.

A blinded RCT by Cramer et al. demonstrated that side-lying manipulations resulted in more cavitations than side-lying positioning, that upside joints cavitated more than downside joints, and that cavitation was correlated with increased gapping of zygopophyseal joints ().

• Objectives The purpose of this study was to use previously validated methods to quantify and relate 2 phenomena associated with chiropractic spinal manipulative therapy (SMT): (1) cavitation and (2) the simultaneous gapping (separation) of the lumbar zygapophyseal (Z) joint spaces.Methods This was a randomized, controlled, mechanistic clinical trial with blinding. Forty healthy participants (18-30 years old) without a history of low-back pain participated. Seven accelerometers were affixed to the skin overlying the spinous processes of L1 to L5 and the S1 and S2 sacral tubercles. Two additional accelerometers were positioned 3 cm left and right lateral to the L4/L5 interspinous space. Participants were randomized into group 1, side-posture SMT (n = 30), or group 2, side-posture positioning (SPP, n = 10). Cavitations were determined by accelerometer recordings during SMT and SPP (left side = upside for both groups); gapping (gapping difference) was determined by the difference between pre- and postintervention magnetic resonance imaging scan joint space measurements. Results of mean gapping differences were compared.Results Upside SMT and SPP joints gapped more than downside joints (0.69 vs − 0.17 mm, P < .0001). Spinal manipulative therapy upside joints gapped more than SPP upside joints (0.75 vs 0.52 mm, P = .03). Spinal manipulative therapy upside joints gapped more in men than in women (1.01 vs 0.49 mm, P < .002). Overall, joints that cavitated gapped more than those that did not (0.56 vs 0.22 mm, P = .01). No relationship was found between the occurrence of cavitation and gapping with upside joints alone (P = .43).Conclusions Zygapophyseal joints receiving chiropractic SMT gapped more than those receiving SPP alone; Z joints of men gapped more than those of women, and cavitation indicated that a joint had gapped but not how much a joint had gapped.

Cramer, G. D., Budavich, M., Bora, P., & Ross, K. (2017). A feasibility study to assess vibration and sound from zygapophyseal joints during motion before and after spinal manipulation. Journal of manipulative and physiological therapeutics, 40(3), 187-200.

Cramer et al. demonstrated that lumbar spine crepitus prevalence increased with age, was higher in participants with low back pain when compared to healthy participants, and decreased after side-lying lumbar manipulation. Further, this study demonstrated the feasibility of a larger study to determine the location of cavitation using accelerometers and directional microphones.

• Objective This feasibility study used novel accelerometry (vibration) and microphone (sound) methods to assess crepitus originating from the lumbar spine before and after side-posture spinal manipulative therapy (SMT).Methods This study included 5 healthy and 5 low back pain (LBP) participants. Nine accelerometers and 1 specialized directional microphone were applied to the lumbar region, allowing assessment of crepitus. Each participant underwent full lumbar ranges of motion (ROM), bilateral lumbar SMT, and repeated full ROM. After full ROMs the participants received side-posture lumbar SMT on both sides by a licensed doctor of chiropractic. Accelerometer and microphone recordings were made during all pre- and post-SMT ROMs. Primary outcome was a descriptive report of crepitus prevalence (average number of crepitus events/participant). Participants were also divided into 3 age groups for comparisons (18-25, 26-45, and 46-65 years).Results Overall, crepitus prevalence decreased pre–post SMT (average pre = 1.4 crepitus/participant vs post = 0.9). Prevalence progressively increased from the youngest to oldest age groups (pre-SMT = 0.0, 1.67, and 2.0, respectively; and post-SMT = 0.5, 0.83, and 1.5). Prevalence was higher in LBP participants compared with healthy (pre-SMT–LBP = 2.0, vs pre-SMT–healthy = 0.8; post-SMT–LBP = 1.0 vs post-SMT–healthy = 0.8), even though healthy participants were older than LBP participants (40.8 years vs 27.8 years); accounting for age: pre-SMT–LBP = 2.0 vs pre-SMT–healthy = 0.0; post-SMT–LBP = 1.0 vs post-SMT–healthy = 0.3.Conclusions Our findings indicated that a larger study is feasible. Other findings included that crepitus prevalence increased with age, was higher in participants with LBP than in healthy participants, and overall decreased after SMT. This study indicated that crepitus assessment using accelerometers has the potential of being an outcome measure or biomarker for assessing spinal joint (facet/zygapophyseal joint) function during movement and the effects of LBP treatments (eg, SMT) on zygapophyseal joint function.

Beffa, R., & Mathews, R. (2004). Does the adjustment cavitate the targeted joint? An investigation into the location of cavitation sounds. Journal of manipulative and physiological therapeutics, 27(2), 118-122.

Beffa et al. attempted to determine if their was a correlation between the techniques used and where a cavitation was heard by using radiography to carefully place microphones over each facet during L5 spinous hook manipulation and lower sacroiliac (SIJ) adjustment. There was no correlation found between cavitation location and technique used; however, some consideration should be given to the close proximity of the intended targets of these techniques (L5/SI versus SIJ) ().

• Background The cavitation sounds heard during chiropractic adjustments of the spine are common phenomena; yet, their location relative to the technique used is relatively untested.Objective The purpose of this study was to locate the cavitation sounds during the L5 spinous hook adjustment and a lower sacroiliac adjustment. The sounds were analyzed for significant difference in location relative to the 2 techniques.Methods Thirty asymptomatic volunteers were randomly divided into 2 equal groups. Each group represented either the spinous hook adjustment or lower sacroiliac adjustment. Subjects had 8 microphones taped to their skin, over the relevant facet and sacroiliac joints. Radiographic confirmation was used to ensure optimal placement of the microphones. Sound signals produced during the adjustments were digitized, recorded, and analyzed statistically.Results The results indicated that no statistically significant correlation existed between the anatomical location of cavitation sounds and the adjustment technique selected.Conclusion Location of cavitation sounds does not appear to have a relationship with type of manipulative technique selected. Further studies using other techniques need to be performed.

Flynn, T. W., Fritz, J. M., Wainner, R. S., & Whitman, J. M. (2003). The audible pop is not necessary for successful spinal high-velocity thrust manipulation in individuals with low back pain. Archives of physical medicine and rehabilitation, 84(7), 1057-1060.

A prospective study by Flynn et al. demonstrated that the presence or absence of an audible cavitation during sacroiliac joint manipulation was not correlated with the improvements in ROM, pain and disability noted following treatment for non-radicular low back pain. That is, those individuals with and without audible cavitations during SIJ manipulation, were likely to exhibit significant improvements for the outcomes measured ().

• A prospective cohort study.Setting: Two outpatient physical therapy clinics located in military medical centers.Participants: A cohort of 71 patients with nonradicular LBP referred to physical therapy.Interventions: Participants underwent a standardized examination and standardized spinal manipulation treatment program. All patients were treated with a sacroiliac (SI) region manipulative technique and the presence or absence of an audible pop was noted.Main Outcome Measures: Subjects were reassessed 48 hours after the manipulation for changes in range of motion (ROM), numeric pain rating scale (PRS) scores, and modified Oswestry Disability Questionnaire (ODQ) scores.Results: An audible pop occurred in 50 of the 71 subjects during the manipulative procedure. Both groups—those who had an audible pop and those who did not—improved over time in flexion ROM, PRS scores, and modified ODQ scores; however, there were no differences between groups (P>.05). Nineteen of the 71 (27%) patients improved dramatically (mean drop in modified ODQ, 67.6%). In 14 of the 19 dramatic responders, an audible pop occurred. However, the odds ratio (1.2; 95% confidence interval, 0.38–4.04) suggested that the occurrence of a manipulative pop would not improve the odds of achieving a dramatic reduction in symptoms after the manipulation.Conclusion: There is no relationship between an audible pop during SI region manipulation and improvement in ROM, pain, or disability in individuals with nonradicular LBP. Additionally, the occurrence of a pop did not improve the odds of a dramatic improvement with manipulation treatment.

Flynn, T. W., Childs, J. D., & Fritz, J. M. (2006). The audible pop from high-velocity thrust manipulation and outcome in individuals with low back pain. Journal of manipulative and physiological therapeutics, 29(1), 40-45.

In a multi-center clinical trial by Flynn et al. demonstrated that a perceived audible pop by the patient or therapist did not correlate with improved outcomes from high-velocity thrust manipulation for patients with nonradicular low back pain during immediate or long-term follow-up ().

• Objective To determine the relationship between an audible pop with spinal manipulation and improvement in pain and function in patients with low back pain.Methods In this pragmatic study, 70 patients from a multicenter clinical trial were randomly assigned to receive high-velocity thrust manipulation and included in this secondary analysis. Patients were managed in physical therapy twice the first week, then once a week for the next 3 weeks, for a total of 5 sessions. A single high-velocity thrust manipulative intervention purported to affect the lumbopelvic region was used during the first two sessions. Therapists recorded whether an audible pop was heard by the patient or therapist. Outcome was assessed with an 11-point pain rating scale, the Oswestry Disability Questionnaire, and measurement of lumbopelvic flexion range of motion. Repeated measures analyses of variance were used to examine whether achievement of a pop resulted in improved outcome.Results An audible pop was perceived in 59 (84%) of the patients. No differences were detected at baseline or at any follow-up period in the level of pain, the Oswestry score, or lumbopelvic range of motion based on whether a pop was achieved (P > .05). The odds ratios and 95% confidence intervals for achieving a successful outcome at each of the follow-up periods all approximated a value of 1, suggesting no improvement in the odds of successful outcome among patients in which an audible pop occurred.Conclusions The results of this pragmatic study suggest that a perceived audible pop may not relate to improved outcomes from high-velocity thrust manipulation for patients with nonradicular low back pain at either an immediate or longer-term follow-up.

Bereznick, D. E., Pecora, C. G., Ross, J. K., & McGill, S. M. (2008). The refractory period of the audible “crack” after lumbar manipulation: a preliminary study. Journal of manipulative and physiological therapeutics, 31(3), 199-203.

Bereznick et al. demonstrated that following lumbar manipulation unitl no audibles were present was followed by a refractory period (defined as a return of less than 50% of the number of cavitations) of about an hour in asymptomatic individuals ().

• Objective This study evaluates if side posture lumbar manipulation is associated with a refractory period of the audible “crack” and if so, to quantify this refractory period across subjects.Methods Three subjects were exposed to multiple “baseline” side posture manipulations until no further audible cracks were recorded. “Test-refractory period” manipulations were administered after a set time (ie, potential refractory period) at which point the number of audible cracks was recorded. The refractory period was declared when a minimum of 50% of the baseline audible “cracks” had recovered during the test manipulations. The study design included 2 clinicians who performed side posture lumbar manipulation on asymptomatic subjects ranging from 38 to 49 years of age.Results The refractory period was 40 minutes for subject A, 70 minutes for subject B, and 95 minutes for subject C. The average refractory period across subjects was 68.33 minutes. The audible “crack” recovery was maintained for the remaining test days once the refractory period had been met.Conclusions The audible “crack” heard during side posture lumbar manipulation is believed to originate from the zygapophyseal joints. This is supported by the presence of a refractory period and by the number of audible “cracks” found per manipulation.
• Methods - Three subjects were exposed to multiple “baseline” side posture manipulations until no further audible cracks were recorded. “Test-refractory period” manipulations were administered after a set time (ie, potential refractory period) at which point the number of audible cracks was recorded. The refractory period was declared when a minimum of 50% of the baseline audible “cracks” had recovered during the test manipulations. The study design included 2 clinicians who performed side posture lumbar manipulation on asymptomatic subjects ranging from 38 to 49 years of age.
• Results - refractory period was 40 minutes for subject A, 70 minutes for subject B, and 95 minutes for subject C. The average refractory period across subjects was 68.33 minutes. The audible “crack” recovery was maintained for the remaining test days once the refractory period had been met.]
• Conclusion - the audible “crack” heard during side posture lumbar manipulation is believed to originate from the zygapophyseal joints . This is supported by the presence of a refractory period and by the number of audible “cracks” found per manipulation.

Ross, J. K., Bereznick, D. E., & McGill, S. M. (2004). Determining cavitation location during lumbar and thoracic spinal manipulation: is spinal manipulation accurate and specific?. Spine, 29(13), 1452-1457.

Ross et al. demonstrated that cavitations from lumbar and thoracic manipulations occured a little more than half of the time one segment from the intended target, with a range up to 2 segements (potentially 3 in the thoracic spine); however, most manipulations resulted in multiple cavitations which included the target segment ().

• Sixty-four asymptomatic participants, ranging in age from 22 to 49 years, volunteered to act as patients for the study. Twenty-eight different clinicians performed thoracic and lumbar spinal manipulative procedures. The range of clinical experience was 1 to 43 years.
• Objectives. The purpose of this study is to first locate the joints that produce an audible sound in response to manipulation (cavitation) during spinal manipulative procedures so that the accuracy and specificity of manipulation can be assessed.Summary of Background Data. Clinicians utilizing spinal manipulative therapy (SMT) claim to be very specific and accurate with the delivery of their dynamic thrust. It has been suggested that the clinical success of SMT is dependent on the accurate delivery of that therapy to the target spinal joints.Methods. Asymptomatic participants received SMT to either the thoracic or lumbar regions of their spine. Accelerometers were secured to the skin over the spinal column, and the relative time at which each accelerometer detected the vibration from the cavitation associated with the SMT was used to calculate the source of the vibration. The site of cavitation was then compared with the target location.Results. For lumbar SMT, the average error from target of 124 cavitations in lumbar procedures was 5.29 cm (at least one vertebra away from target), with a range of 0 to 14 cm. Of these cavitations, 57 were deemed to be accurate and 67 were deemed to be inaccurate. The average error from target of 54 cavitations in the thoracic spine was 3.5 cm, with a range of 0 to 9.5 cm. Of these cavitations, 29 were deemed to be accurate and 25 were deemed to be inaccurate. In most cases, individual manipulative procedures were associated with multiple cavitations ranging from 2 to 6.Conclusions. In the lumbar spine, SMT was accurate about half the time. However, because most procedures were associated with multiple cavitations, in most cases, at least one cavitation emanated from the target joints. Inthe thoracic spine, SMT appears to be more accurate.

Mourad, F., Dunning, J., Zingoni, A., Iorio, R., Butts, R., Zacharko, N., & Fernández-de-las-Peñas, C. (2019). Unilateral and Multiple Cavitation Sounds During Lumbosacral Spinal Manipulation. Journal of Manipulative and Physiological Therapeutics, 42(1), 12-22.

Mourad et al. demonstrated that the side-lying, rotatory lumbar manipulations resulted in cavitations on the ipsilateral or contralateral side of the targeted segment in approximately equal proportions, and on both sides only 2% of the time, with an average of 5 audibles (range 2-9) recorded permanipulation ().

• Objective The purpose of this study was to determine from which side of the spine the popping sound (PS) emanates during side-lying, rotatory high-velocity low-amplitude (HVLA) thrust manipulation directed to the L5-S1 articulation using a time-frequency analysis. Secondary aims were to calculate the average number of PSs, the duration of lumbar thrust manipulation, and the duration of a single PS.Methods Thirty-four asymptomatic participants received 2 lumbar HVLA thrust manipulations targeting the right and left L5-S1 articulations. Two high sampling rate accelerometers were secured bilaterally 25 mm lateral to the midline of the L5-S1 interspace. For each manipulation, 2 audio signals were extracted and singularly processed via spectrogram calculation to obtain the release of energy over time on each side of the lumbosacral junction.Results During 60 HVLA thrust manipulations, it was measured a total of 320 PSs. Of those PSs, 176 occurred ipsilateral and 144 occurred contralateral to the targeted L5-S1 articulation; that is, the PS was no more likely to occur on the upside than the downside facet after right or left rotatory L5-S1 HVLA thrust manipulation. Moreover, PSs occurring on both sides at the same time were detected very rarely (ie, 2% of cases) with the lumbar HVLA thrust manipulations. The mean number of audible PSs per lumbosacral HVLA thrust manipulation was 5.27 (range 2-9). The mean duration of a single manipulation was 139.13 milliseconds (95% confidence interval: 5.61-493.79), and the mean duration of a single PS was 2.69 milliseconds (95% confidence interval: 0.95-4.59).Conclusion Based on our findings, spinal manipulative therapy practitioners should expect multiple PSs that most often occur on the upside or the downside facet articulations when performing HVLA thrust manipulation to the lumbosacral junction (ie, L5-S1). However, whether the multiple PSs found in this study emanated from the same joint or adjacent ipsilateral or contralateral facet joints remains unknown. A single model may not necessarily be able to explain all of the audible sounds during HVLA thrust manipulation.

Herzog, W., Zhang, Y. T., Conway, P. J., & Kawchuk, G. N. (1993). Cavitation sounds during spinal manipulative treatments. Journal of manipulative and physiological therapeutics, 16(8), 523.

Herzog et al. demonstrated that the clinicians perspective on whether a cavitation occurred, when compared to accelerometry, is very accurate ().

• Objective: The purpose of this study was to confirm a practitioner's perception of cavitation during spinal manipulative therapy in a clinically relevant situation using accelerometer recordings.Design: Experimental study.Setting: Human Performance Laboratory and Sports Medicine Center, University of Calgary.Participants: Twenty-eight patients from a single practitioner's patient pool who had pain in the area of the thoracic spine.Intervention: Spinal manipulative treatment (SMT) on the transverse process of T4 using a reinforced unilateral contact and delivering a thrust in the posterior to anterior direction.Main outcome measures: Instantaneous acceleration signals obtained from the spinous process of T3 during SMT and the practitioner's perception if cavitation had occurred or not at the end of each treatment.Conclusions: It appears that cavitation may be measured during SMT using accelerometry and that a practitioner's perception of the occurrence of cavitation during SMT is very accurate.

Conway, P. J. W., Herzog, W., Zhang, Y., Hasler, E. M., & Ladly, K. (1993). Forces required to cause cavitation during spinal manipulation of the thoracic spine. Clinical Biomechanics, 8(4), 210-214.

Conway et al. demonstrated that the forces correlated with cavitation during manipulation of the thoracic spine were 364 N with a standard deviation of 106 N ().

• The purpose of this study was to measure the forces exerted during spinal manipulative therapy of the thoracic spine simultaneously with corresponding cavitation signals. Forces were measured using a thin, flexible pressure mat which was placed on patients over the contact area between doctor and patient. Cavitation signals were measured using a skin mounted accelerometer on the spinous process of a vertebral body adjacent to the manipulated vertebral body. Mean forces of spinal manipulative therapy at the instant of cavitation were 364 N with a standard deviation of 106 N. These values are considerably larger than corresponding values reported for cavitation at metacarpophalangeal joints. The precise factors causing cavitation of the spinal joints could not be determined. Study designs which may allow identification of these factors are suggested.

Dunning, J., Mourad, F., Zingoni, A., Iorio, R., Perreault, T., Zacharko, N., … & Cleland, J. A. (2017). Cavitation sounds during cervicothoracic spinal manipulation. International Journal of Sports Physical Therapy, 12(4), 642.

Dunning et al. investigated cavitations from cervicothoracic thrust manipulations targeting the right and left T1/T2 articulation on patients with upper trapezius myalgia. The findings demonstrate that cavitations are likely to occur unilaterally, on the side the head is rotated toward, multiple cavitation should be expected, and due to the presence of multi-peak energy bursts and sounds of multiple frequencies, the cavitation hypothesis of intra-articular gas bubble collapse is potentially false, only one source of sounds, or must be occuring at multiple joints of different size and shape.

• Background No study has previously investigated the side, duration or number of audible cavitation sounds during high-velocity low-amplitude (HVLA) thrust manipulation to the cervicothoracic spine.Purpose The primary purpose was to determine which side of the spine cavitates during cervicothoracic junction (CTJ) HVLA thrust manipulation. Secondary aims were to calculate the average number of cavitations, the duration of cervicothoracic thrust manipulation, and the duration of a single cavitation.Study Design Quasi-experimental studyMethods Thirty-two patients with upper trapezius myalgia received two cervicothoracic HVLA thrust manipulations targeting the right and left T1-2 articulation, respectively. Two high sampling rate accelerometers were secured bilaterally 25 mm lateral to midline of the T1-2 interspace. For each manipulation, two audio signals were extracted using Short-Time Fourier Transformation (STFT) and singularly processed via spectrogram calculation in order to evaluate the frequency content and number of instantaneous energy bursts of both signals over time for each side of the CTJ.Result Unilateral cavitation sounds were detected in 53 (91.4%) of 58 cervicothoracic HVLA thrust manipulations and bilateral cavitation sounds were detected in just five (8.6%) of the 58 thrust manipulations; that is, cavitation was significantly (p<0.001) more likely to occur unilaterally than bilaterally. In addition, cavitation was significantly (p<0.0001) more likely to occur on the side contralateral to the clinician's short-lever applicator. The mean number of audible cavitations per manipulation was 4.35 (95% CI 2.88, 5.76). The mean duration of a single manipulation was 60.77 ms (95% CI 28.25, 97.42) and the mean duration of a single audible cavitation was 4.13 ms (95% CI 0.82, 7.46). In addition to single-peak and multi-peak energy bursts, spectrogram analysis also demonstrated high frequency sounds, low frequency sounds, and sounds of multiple frequencies for all 58 manipulations.Discussion Cavitation was significantly more likely to occur unilaterally, and on the side contralateral to the short-lever applicator contact, during cervicothoracic HVLA thrust manipulation. Clinicians should expect multiple cavitation sounds when performing HVLA thrust manipulation to the CTJ. Due to the presence of multi-peak energy bursts and sounds of multiple frequencies, the cavitation hypothesis (i.e. intra-articular gas bubble collapse) alone appears unable to explain all of the audible sounds during HVLA thrust manipulation, and the possibility remains that several phenomena may be occurring simultaneously.

Demoulin, C., Baeri, D., Toussaint, G., Cagnie, B., Beernaert, A., Kaux, J. F., & Vanderthommen, M. (2018). Beliefs in the population about cracking sounds produced during spinal manipulation. Joint Bone Spine, 85(2), 239-242.

Demoulin et al. surveyed 100 individuals, 60 with no history of spinal manipulation, including 40 who were asymptomatic and 20 with current spinal pain, demonstrating that sounds were ascribed to vertebral repositioning by 49%, friction between two vertebras by 23%, and 9% ascribed the sound to the more likely formation of a gas bubbles in the joint, and the sound was mistakenly considered to indicator of successful manipulation by 40% of participants (). This study suggests that beliefs of most patients do not accurately reflect the body of research on manipulations.

• Objectives To examine beliefs about cracking sounds heard during high-velocity low-amplitude (HVLA) thrust spinal manipulation in individuals with and without personal experience of this technique.Methods We included 100 individuals. Among them, 60 had no history of spinal manipulation, including 40 who were asymptomatic with or without a past history of spinal pain and 20 who had nonspecific spinal pain. The remaining 40 patients had a history of spinal manipulation; among them, 20 were asymptomatic and 20 had spinal pain. Participants attended a one-on-one interview during which they completed a questionnaire about their history of spinal manipulation and their beliefs regarding sounds heard during spinal manipulation.Results Mean age was 43.5 ± 15.4 years. The sounds were ascribed to vertebral repositioning by 49% of participants and to friction between two vertebras by 23% of participants; only 9% of participants correctly ascribed the sound to the formation of a gas bubble in the joint. The sound was mistakenly considered to indicate successful spinal manipulation by 40% of participants. No differences in beliefs were found between the groups with and without a history of spinal manipulation.Conclusions Certain beliefs have documented adverse effects. This study showed a high prevalence of unfounded beliefs regarding spinal manipulation. These beliefs deserve greater attention from healthcare providers, particularly those who practice spinal manipulation.

Cleland, J. A., Flynn, T. W., Childs, J. D., & Eberhart, S. (2007). The audible pop from thoracic spine thrust manipulation and its relation to short-term outcomes in patients with neck pain. Journal of manual & manipulative therapy, 15(3), 143-154.

Cleland et al. investigated cervical manipulations, cavitations and outcomes, demonstrating that no correlation could be found between the number of cavitations and the amount of improvement in pain, disability or range of motion (ROM).

• Clinicians routinely consider the success of a thrust manipulation technique based on the presence or absence of an audible pop despite the lack of evidence suggesting that this pop is associated with improved outcomes. The purpose of this study was to determine the relationship between the number of audible pops with thoracic spinal manipulation and improvement in pain and function in patients with mechanical neck pain. In this prospective cohort study, 78 patients referred to physical therapy with mechanical neck pain underwent a standardized examination and thoracic spine manipulation treatment protocol. All patients were treated with a total of 6 thrust manipulation techniques directed to the thoracic spine followed by a basic cervical range of motion exercise. The treating clinician recorded the presence or absence of a pop during each manipulation. Outcomes were assessed at a 2-4 day follow-up with an 11-point numeric pain rating (NPRS), the Neck Disability Index, the patient Global Rating of Change (GROC), and measurements of cervical range of motion (CROM). The relationship between the number of pops and change scores for pain, disability, and CROM was first examined using Pearson correlation coefficients. Individuals were then categorized as having received ≤3 or >3 pops. Repeated measures analyses of variance were used to examine whether achievement of >3 pops resulted in improved outcome. Seventy-eight patients with a mean age of 42 (SD 11.3) years participated in the study. Pearson correlation coefficients revealed no significant correlation existed between the number of pops and outcomes with the exception of 3 of the 6 CROM measurements, which were inversely related. There was no significant interaction for group X time for any of the dependent measures (P>0.05). The odds ratio for patients experiencing dramatic improvement was in favor of the group experiencing ≤3 pops but this was not clinically meaningful (1.3: 95% CI 0.46, 3.7). The results of this analysis provide preliminary evidence for the hypothesis that there is no relationship between the number of audible pops during thoracic spine thrust manipulation and clinically meaningful improvements in pain, disability, or CROM in patients with mechanical neck pain. Additionally, a greater number of audible pops experienced was not associated with a dramatic improvement with manipulation treatment.

Sillevis, R., & Cleland, J. (2011). Immediate effects of the audible pop from a thoracic spine thrust manipulation on the autonomic nervous system and pain: a secondary analysis of a randomized clinical trial. Journal of manipulative and physiological therapeutics, 34(1), 37-45.

In a secondary analysis of an RCT, Sillevis et al. demonstrated that there was no difference in autonomic response (pupil response) or perceived pain following cervical mobilization, cervical manipulation without cavitation, and cervical manipulation with cavitation ().

• Purpose This study investigated the immediate effects of audible joint sounds following a supine T3-T4 spinal thrust manipulation on the autonomic nervous system activity using a fully automated pupillometry system in patients with chronic neck pain. An additional aim was to determine if audible sounds as perceived by the therapist were associated with the reduction of pain following manipulation.Methods One hundred subjects with chronic neck pain completed the study protocol. The Mann-Whitney U test was used to compare the change scores of the 3 measuring points between the one-pop and multiple-pop groups. Subjects were randomized into either a manipulation or a mobilization group. A method of automated pupillometry was used in this study to capture pupil responsiveness.Results The analysis showed that there was no significant difference between the 2 groups (P > .05). The Kruskal-Wallis test was used to compare the median change scores between the mobilization, no-pop, and pop groups. The analysis showed that there was no statistically significant difference in the amount of change in pupil diameter between the 3 groups (P > .05).The Mann-Whitney U test demonstrated that the no-pop group (P = .031) and the multiple-pop group (P = .014) had a significant reduction of pain; however, it did not reach the minimal clinically significant level of 13 mm on the visual analog scale.Conclusions The results of this study provided evidence that the presence of joint sounds does not influence the overall activity of the autonomic nervous system following a thrust manipulation or contribute to the reduction of pain in patients with chronic neck pain.

Patient Education

Riley, S. P., Bialosky, J., Cote, M. P., Swanson, B. T., Tafuto, V., Sizer, P. S., & Brismée, J. M. (2015). Thoracic spinal manipulation for musculoskeletal shoulder pain: can an instructional set change patient expectation and outcome?. Manual therapy, 20(3), 469-474.

Riley et al. demonstrated that although a positive education set prior to manipulation positively impacted perception following manipulation, it did not significantly alter disability or pain when compared to patients that received manipulation without education ().

• To examine: 1) patients' baseline expectations for treatment outcome of thoracic high velocity low amplitude thrust manipulations (HVLATM) to the thoracic spine for shoulder pain; 2) if the message conveyed by the clinician changed the patients' expectation; 3) any differences in outcome based on expectation independent of messaging.; and 4) any differences in outcome for those patients whose expectations significantly changed as a result of the messaging.Background Thoracic HVLATM may be an effective intervention for patients suffering from musculoskeletal shoulder pain. The role of expectation in the treatment effectiveness of this intervention has not been established.Methods Subjects' expectations regarding the effectiveness of HVLATM on shoulder pain were recorded at baseline. This was reassessed immediately following the provision of positive or neutral instructional set. The subjects then received a thoracic or scapular HVLATM. The Shoulder Pain and Disability Index (SPADI) and the numeric pain rating scale (NPRS) were used as outcomes measures.Results There was a 10 subject change (23%) in positive expectation that was statistically significant (p = 0.019) following a positive message. There was no statistically significant difference in pain and function when these subjects were compared to all other subjects.Conclusion Although patients' expectations of positive outcome significantly changed when providing a positive instructional set, these changes did not translate into clinically significant short term changes in shoulder pain and function.

Differences in Kinematics associated with Dysfunction

Latimer, J., Lee, M., Adams, R., & Moran, C. M. (1996). An investigation of the relationship between low back pain and lumbar posteroanterior stiffness. Journal of manipulative and physiological therapeutics, 19(9), 587-591.

• OBJECTIVE: To investigate the relationship between low back pain (LBP) and lumbar posteroanterior (PA) stiffness. DESIGN: A repeated-measures design was used to measure lumbar posteroanterior stiffness on two occasions in subjects with and without LBP. SUBJECTS: Twenty-five subjects with acute or subacute LBP and twenty-five pain-free subjects participated. Pain subjects reported pain on the application of a manual PA force to the lumbar spine and had no contraindication to PA stiffness testing. Pain-free subjects reported no history of LBP requiring treatment, and obtained a score of 0 on the McGill Pain Questionnaire. METHODS: PA stiffness was measured in subjects with LBP when (a) they first presented with pain and (b) when pain had resolved by more than 80%. Pain-free subjects, matched with pain subjects on gender, age, vertebral level to be tested and time between tests, were also measured on two occasions, to control for the effects of repeated stiffness testing and the passing of time. RESULTS: In subjects with low back pain stiffness decreased by 1.21 N/mm between test 1 and test 2. A paired t test found a significant difference between the tests (t = 3.04, df = 24, p = .006). In subjects without pain, there was an increase in stiffness of 0.74 N/mm between test 1 and test 2; a paired t test found no significant difference between the tests (t = -1.673, df = 24, p = .107). CONCLUSIONS: Subjects with LBP showed increased PA stiffness compared with when they had little or no pain, whereas pain-free subjects showed unchanged PA stiffness over time.

Abbott, J. H., Fritz, J. M., McCane, B., Shultz, B., Herbison, P., Lyons, B., … & Walsh, R. M. (2006). Lumbar segmental mobility disorders: comparison of two methods of defining abnormal displacement kinematics in a cohort of patients with non-specific mechanical low back pain. BMC musculoskeletal disorders, 7(1), 45.

Abbott et al. demonstrated that using radiographs to determine either a Gaussian model of 2-standard deviations from mean, or a within-subjects comparison of mean normalized contribution-to-total-lumbar-motion, were effective for identifying lumbar segmental instability, and this study demonstrated that the prevalence of instability was higher in those experiencing low back pain ().

• Background Lumbar segmental rigidity (LSR) and lumbar segmental instability (LSI) are believed to be associated with low back pain (LBP), and identification of these disorders is believed to be useful for directing intervention choices. Previous studies have focussed on lumbar segmental rotation and translation, but have used widely varying methodologies. Cut-off points for the diagnosis of LSR & LSI are largely arbitrary. Prevalence of these lumbar segmental mobility disorders (LSMDs) in a non-surgical, primary care LBP population has not been established.Methods A cohort of 138 consecutive patients with recurrent or chronic low back pain (RCLBP) were recruited in this prospective, pragmatic, multi-centre study. Consenting patients completed pain and disability rating instruments, and were referred for flexion-extension radiographs. Sagittal angular rotation and sagittal translation of each lumbar spinal motion segment was measured from the radiographs, and compared to a reference range derived from a study of 30 asymptomatic volunteers. In order to define reference intervals for normal motion, and define LSR and LSI, we approached the kinematic data using two different models. The first model used a conventional Gaussian definition, with motion beyond two standard deviations (2sd) from the reference mean at each segment considered diagnostic of rotational LSMD and translational LSMD. The second model used a novel normalised within-subjects approach, based on mean normalised contribution-to-total-lumbar-motion. An LSMD was then defined as present in any segment that contributed motion beyond 2sd from the reference mean contribution-to-normalised-total-lumbar-motion. We described reference intervals for normal segmental mobility, prevalence of LSMDs under each model, and the association of LSMDs with pain and disability.Results With the exception of the conventional Gaussian definition of rotational LSI, LSMDs were found in statistically significant prevalences in patients with RCLBP. Prevalences at both the segmental and patient level were generally higher using the normalised within-subjects model (2.8 to 16.8% of segments; 23.3 to 35.5% of individuals) compared to the conventional Gaussian model (0 to 15.8%; 4.7 to 19.6%). LSMDs are associated with presence of LBP, however LSMDs do not appear to be strongly associated with higher levels of pain or disability compared to other forms of non-specific LBP.Conclusion LSMDs are a valid means of defining sub-groups within non-specific LBP, in a conservative care population of patients with RCLBP. Prevalence was higher using the normalised within-subjects contribution-to-total-lumbar-motion approach.

Ahmadi, A., Maroufi, N., Behtash, H., Zekavat, H., & Parnianpour, M. (2009). Kinematic analysis of dynamic lumbar motion in patients with lumbar segmental instability using digital videofluoroscopy. European spine journal, 18(11), 1677-1685.

Ahmadi et al. demonstrated (using video fluoroscopy) that intersegmental translation of the L1–L2 and L5–S1 segments during flexion and extension of the spine, was greater in patients with diagnosed lumbar spine instability (LSI).

• Intersegmental linear translation was significantly higher in patients during both flexion and extension movements at L5–S1 segment (p < 0.05). Arc length of PICR was significantly higher in patients for L1–L2 and L5–S1 motion segments during extension movement (p < 0.05). This study determined some kinematic differences between two groups during the full range of lumbar spine. Devices, such as digital videofluoroscopy can assist in identifying better criteria for diagnosis of LSI in otherwise nonspecific low back pain patients in hope of providing more specific treatment.
• The study design is a prospective, case–control. The aim of this study was to develop a reliable measurement technique for the assessment of lumbar spine kinematics using digital video fluoroscopy in a group of patients with low back pain (LBP) and a control group. Lumbar segmental instability (LSI) is one subgroup of nonspecific LBP the diagnosis of which has not been clarified. The diagnosis of LSI has traditionally relied on the use of lateral functional (flexion–extension) radiographs but use of this method has proven unsatisfactory. Fifteen patients with chronic low back pain suspected to have LSI and 15 matched healthy subjects were recruited. Pulsed digital videofluoroscopy was used to investigate kinematics of lumbar motion segments during flexion and extension movements in vivo. Intersegmental linear translation and angular displacement, and pathway of instantaneous center of rotation (PICR) were calculated for each lumbar motion segment. Movement pattern of lumbar spine between two groups and during the full sagittal plane range of motion were analyzed using ANOVA with repeated measures design. Intersegmental linear translation was significantly higher in patients during both flexion and extension movements at L5–S1 segment (p < 0.05). Arc length of PICR was significantly higher in patients for L1–L2 and L5–S1 motion segments during extension movement (p < 0.05). This study determined some kinematic differences between two groups during the full range of lumbar spine. Devices, such as digital videofluoroscopy can assist in identifying better criteria for diagnosis of LSI in otherwise nonspecific low back pain patients in hope of providing more specific treatment.

Lin, J. J., & Yang, J. L. (2006). Reliability and validity of shoulder tightness measurement in patients with stiff shoulders. Manual therapy, 11(2), 146-152.

Lin et al. demonstrated good intratester and intertester reliability for determining shoulder tightness; further, correlations were demonstrated between anterior shoulder tightness, below shoulder adduction tightness and limited external rotation, as well as posterior shoulder tightness, cross-body adduction and limited internal rotation.

• The purposes of this study were (1) to examine intratester and intertester reliability of measurement of anterior and posterior shoulder tightness in patients with stiff shoulders (SS), and (2) to assess construct validity by determining the relations between shoulder tightness, shoulder range of motion (ROM), and self-report measures of functional limitation. Anterior and posterior shoulder tightness were measured by two testers in below-chest abduction and cross-chest adduction tests with an inclinometer, respectively, in 16 patients with SS. Both the intratester and intertester reliability for shoulder tightness measurements were good (intratester ICC=0.84 and 0.91; intertester ICC=0.82 and 0.89). The limit of intra-tester and inter-tester agreement (mean, −0.3±4.4°) was acceptable as compared to the standard deviations of the measurements (range, 6.2–7.4°). Significant relationships between internal rotation and posterior shoulder tightness (, ), external rotation and anterior shoulder tightness (, ), and functional disabilities and posterior shoulder tightness (, ) were found. Significant correlations between shoulder internal rotation and cross-chest adduction, shoulder external rotation and below-chest abduction were observed, indicating that internal and external rotations might be related to posterior and anterior shoulder stiffness. The study also revealed significant relationship between functional disabilities and cross-chest adduction. Below-chest abduction and cross-chest adduction were found to provide reliable data. The construct validity of the abduction and adduction tests is supported by the relationship among these measurements, shoulder ROM, and functional disabilities in patients with SS.