Effects of a stretching protocol for the pectoralis minor on muscle length, function, and scapular kinematics in individuals with and without shoulder pain

Prompt Impact of Muscle Energy Technique on Pectoralis Muscle Tightness in Computer Users: A Quasi-Experimental Study

Tightness of the pectoralis minor muscle has been a common characteristic of abnormal posture. Prolonged inappropriate posture while using computers/laptops results in musculoskeletal problems, mainly in the upper limb. This study aims to see how the muscular energy technique affected pectoralis minor tightness in computer users right away. This study included 65 individuals aged 20-40 years following the inclusion/exclusion criteria. Participants received muscle energy technique for the pectoralis minor muscle. Pre- and post-assessment included the evaluation of pectoralis minor length, round shoulder posture (RSP), and forward head posture (FHP). We used the Kolmogorov-Smirnov test to assess the normality of data, as this study included > 50 participants. Data analysis was conducted using a paired t-test for within-group analysis. The outcome measures demonstrated significant improvement (p < 0.001). In conclusion, the muscle energy technique is effective in reducing muscle tightness, improving RSP and reducing FHP.

Effectiveness of the Fascial Manipulation Approach Associated with a Physiotherapy Program in Recurrent Shoulder Disease

Shoulder pain is a serious clinical disease frequently related to absence from work. It is characterized by pain and stiffness, probably connected to the presence of an inflammatory substrate involving gleno-humeral capsule and collagen tissues. A physiotherapy program has shown to be effective for the conservative treatment of this disorder. Our aim is to assess if a manual treatment directed to fascial tissues could obtain better improvement regarding pain, strength, mobility, and function. A total of 94 healthcare workers with recurrent shoulder pain were recruited and then randomized in two groups: the control group (CG) underwent a five-session physiotherapy program; the study group (SG) underwent three sessions of physiotherapy and two sessions of fascial manipulation (FM) technique. At the end of the treatment phase, both groups improved every outcome. Despite few statistical differences between groups, at the follow-up visit, a greater percentage of subjects in SG overcame the minimal clinical important difference (MCID) in every outcome. We conclude that FM is effective for treatment of shoulder pain and further studies should better assess how to manage this treatment to obtain better results.

Exercise for rotator cuff tendinopathy: Proposed mechanisms of recovery

Rotator cuff (RC) tendinopathy is a common recurrent cause of shoulder pain, and resistance exercise is the first-line recommended intervention. Proposed causal mechanisms of resistance exercise for patients with RC tendinopathy consist of four domains: tendon structure, neuromuscular factors, pain and sensorimotor processing, and psychosocial factors. Tendon structure plays a role in RC tendinopathy, with decreased stiffness, increased thickness, and collagen disorganization. Neuromuscular performance deficits of altered kinematics, muscle activation, and force are present in RC tendinopathy, but advanced methods of assessing muscle performance are needed to fully assess these factors. Psychological factors of depression, anxiety, pain catastrophizing, treatment expectations, and self-efficacy are present and predict patient-reported outcomes. Central nervous system dysfunctions also exist, specifically altered pain and sensorimotor processing. Resisted exercise may normalize these factors, but limited evidence exists to explain the relationship of the four proposed domains to trajectory of recovery and defining persistent deficits limiting outcomes. Clinicians and researchers can use this model to understand how exercise mediates change in patient outcomes, develop subgroups to deliver patient-specific approach for treatment and define metrics to track recovery over time. Supporting evidence is limited, indicating the need for future studies characterizing mechanisms of recovery with exercise for RC tendinopathy.

Effects of a High-Volume 7-Week Pectoralis Muscle Stretching Training on Muscle Function and Muscle Stiffness

BACKGROUND

There is evidence that high-volume static stretching training of the lower limbs can increase the range of motion (ROM) while decreasing muscles stiffness. However, to date, there is no evidence on the effects of upper limb stretching training or its effect mechanism. Therefore, this study aimed to investigate the effects of a comprehensive 7-week static stretching training program of the pectoralis major muscle (PMa) on glenohumeral joint ROM, muscle force, and muscle stiffness.

METHODS

Thirty-eight healthy, physically active participants (23 male, 15 female) were randomly assigned to either the PMa-static stretching intervention (PMa-SS) group or the control group. The PMa-SS group performed a 7-week intervention comprising three sessions a week for 15 min per session, including three static stretching exercises of the PMa for 5 min each. Before and after the intervention period, shoulder extension ROM, muscle stiffness of the PMa (pars clavicularis), and maximal voluntary isometric contraction (MVIC) peak torque (evaluated at both long (MVIC_long) and short (MVIC_short) muscle lengths) were investigated on a custom-made testing device at 45° shoulder abduction.

RESULTS

In the PMa-SS group, the shoulder extension ROM (+ 6%; p < 0.01; d = 0.92) and the MVIC_long (+ 11%; p = 0.01; d = 0.76) increased. However, there were no significant changes in MVIC_short or in PMa muscle stiffness in the PMa-SS group. In the control group, no changes occurred in any parameter.

CONCLUSION

In addition to the increase in ROM, we also observed an improved MVIC at longer but not shorter muscle lengths. This potentially indicates an increase in fascicle length, and hence a likely increase in sarcomeres in series.

Managing Scapular Dyskinesis

Scapular dyskinesis, the impairment of optimal scapular position and motion, is common in association with shoulder injury. A comprehensive evaluation process can show the causative factors and lead to effective treatment protocols. The complexity of scapular motion and the integrated relationship between the scapula, humerus, trunk, and legs suggest a need to develop rehabilitation programs that involve all segments working as a unit rather than isolated components. This is best accomplished with an integrated rehabilitation approach that includes rectifying deficits in mobility, strength, and motor control but not overtly focusing on any one area.

The Combined Effect of the Trapezius Muscle Strengthening and Pectoralis Minor Muscle Stretching on Correcting the Rounded Shoulder Posture and Shoulder Flexion Range of Motion among Young Saudi Females: A Randomized Comparative Study

BACKGROUND

The shortening of the pectoralis minor muscle (PMi-M) and weakening of the lower trapezius muscle (LTr-M) affect scapular movement, resulting in the development of a rounded shoulder posture and reduction in the shoulder flexion range of motion (SFROM).

OBJECTIVE

This study evaluated the combined effect of LTr-M strengthening and PMi-M stretching on correcting the rounded shoulder postures and SFROM among young Saudi females.

METHODS

This study was based on a two-arm parallel-group repeated measures randomized comparative design. A total of sixty female participants with rounded shoulder postures were recruited and randomly allocated into groups 1 and 2 (n = 30/group). Each group performed supervised PMi-M stretching; however, group 2 performed a combination of LTr-M strengthening and PMi-M stretching. The outcomes, including rounded shoulder posture and SFROM, were assessed using the pectoralis minor length test (PMLT) and universal goniometer. A repeated measure ANOVA was used to compare the differences within-group and between-group for the outcomes measures at one-week (baseline) pre-intervention, two weeks, and three -weeks post-intervention. The significance level was set at q > 2.00 and p < 0.05 for all respective statistical analyses.

RESULTS

The within-group comparison revealed significant improvements (q > 2.00) in the outcomes of PMLT and SFROM when comparing their post-intervention scores to the baseline scores. The between-group comparison revealed a significant and an insignificant (q < 2.00) difference in the outcomes of PMLT and SFROM, respectively when comparing their scores at the second- and third-week post-intervention. Furthermore, the effect size of the intervention suggests an advantage of group 2 over group 1 in increasing the resting length of the PMi-M only among young Saudi females.

CONCLUSIONS

The combined effect of LTr-M strengthening and PMi-M stretching was more beneficial than PMi-M stretching alone in correcting the rounded shoulder posture among young Saudi females by increasing PMi-M resting length. However, it could not yield a differential improvement in the SFROM outcome among them.

"You have (rotator cuff related) shoulder pain, and to treat it, I recommend exercise." A scoping review of the possible mechanisms underpinning exercise therapy

BACKGROUND

Exercise is considered to be both essential and at the forefront of the management of rotator cuff-related shoulder pain (RCRSP). Despite this, many fail to substantially improve with exercise-based treatment. Hence, expanding the current knowledge about the possible mechanisms of exercise for RCRSP is critical.

OBJECTIVE

To synthesise the range of mechanisms proposed for exercise in people with RCRSP.

DESIGN

Scoping review METHODS: A systematic search of the Physiotherapy Evidence Database (PEDro) was conducted from inception to July 3, 2022. Two reviewers conducted the search and screening process and one reviewer extracted the data from each study. Randomised clinical trials using exercise for the management of RCRSP of any duration were included. The PEDro search terms used were "fitness training", "strength training", "stretching, mobilisation, manipulation, massage", "upper arm, shoulder, or shoulder girdle", "pain", and "musculoskeletal". Data were analysed using quantitative and qualitative approaches.

RESULTS

626 studies were identified and 110 were included in the review. Thirty-two unique mechanisms of exercise were suggested by clinical trialists, from which 4 themes emerged: 1) neuromuscular 2) tissue factors 3) neuro-endocrine-immune 4) psychological. Neuromuscular mechanisms were proposed most often (n = 156, 77%). Overall, biomedical mechanisms of exercise were proposed in 95% of cases.

CONCLUSIONS

The causal explanation for the beneficial effect of exercise for RCRSP in clinical research is dominated by biomedical mechanisms, despite a lack of supporting evidence. Future research should consider testing the mechanisms identified in this review using mediation analysis to progress knowledge on how exercise might work for RCRSP.

Pectoralis minor syndrome - review of pathoanatomy, diagnosis, and management of the primary cause of neurogenic thoracic outlet syndrome

Thoracic outlet syndrome is an umbrella term for compressive pathologies in the supraclavicular and infraclavicular fossae, with the vast majority being neurogenic in nature. These compressive neuropathies, such as pectoralis minor syndrome, can be challenging problems for both patients and physicians. Robust understanding of thoracic outlet anatomy and scapulothoracic biomechanics are necessary to distinguish neurogenic vs. vascular disorders and properly diagnose affected patients. Repetitive overhead activity, particularly when combined with scapular dyskinesia, leads to pectoralis minor shortening, decreased volume of the retropectoralis minor space, and subsequent brachial plexus compression causing neurogenic thoracic outlet syndrome. Combining a thorough history, physical examination, and diagnostic modalities including ultrasound-guided injections are necessary to arrive at the correct diagnosis. Rigorous attention must be paid to rule out alternate etiologies such as peripheral neuropathies, vascular disorders, cervical radiculopathy, and space-occupying lesions. Initial nonoperative treatment with pectoralis minor stretching, as well as periscapular and postural retraining, is successful in the majority of patients. For patients that fail nonoperative management, surgical release of the pectoralis minor may be performed through a variety of approaches. Both open and arthroscopic pectoralis minor release may be performed safely with effective resolution of neurogenic symptoms. When further indicated by the preoperative workup, this can be combined with suprascapular nerve release and brachial plexus neurolysis for complete infraclavicular thoracic outlet decompression.

Bilateral Comparison of Anterior Shoulder Position in Elite Tennis Players

Background

In elite tennis players, musculoskeletal adaptations in the dominant upper extremity have been reported for range of motion, strength, and scapular biomechanics. In addition to scapular dysfunction, tightness and inflexibility of the pectoral musculature have been identified as risk factors for the development of overuse shoulder injury in overhead athletes.

Hypothesis

Differences in anterior shoulder position will be identified between the dominant and non-dominant extremity in elite tennis players. The purpose of this study was to examine bilateral differences in anterior shoulder posture measured using a double square in elite tennis players without shoulder injury.

Study Design

Descriptive Laboratory Study.

Methods

Three hundred and six uninjured elite tennis players were measured in the supine position using a double square method to measure anterior shoulder position. The distance from the surface of the table to the anterior most position of the shoulder (in millimeters) was measured bilaterally and compared. A dependent t-test was used to test for significant differences in anterior shoulder position between the dominant and non-dominant extremity.

Results

One hundred thirty-three males and 173 females were included in this study with a mean age of 16.58 years. The mean difference between extremities indicates increased anterior shoulder positioning on the dominant shoulder of 7.65 mm in females, and 8.72 in males. Significantly greater (p<.001) anterior shoulder position measures were documented on the dominant shoulder as compared to the non-dominant shoulder.

Conclusions

The results of this study showed significantly (p<.001) greater anterior shoulder position on the dominant extremity of elite male and female tennis players. The differences of 7-8mm between extremities has clinical application for interpreting anterior shoulder position test results in this population.

Level of Evidence

3.

Arthroscopic release of the pectoralis minor tendon from the coracoid for pectoralis minor syndrome

Purpose

The term “pectoralis minor syndrome” refers to this constellation of symptoms that can occur when the pectoralis minor (Pm) is shortened and contracted. Release of the tendon of the Pm from the coracoid has been reported to provide substantial clinical improvement to patients presenting with pectoralis minor syndrome. The purpose of this study was (1) to describe the technique for endoscopic release of pectoralis minor tendon at the subdeltoid space, (2) to classify the pectoralis minor syndrome according to its severity and (3) and to report the short-term outcomes of this procedure in a consecutive series of patients diagnosed with pectoralis minor syndrome.

Methods

Endoscopic release of the pectoralis minor tendon was performed in a series of 10 patients presenting with pectoralis minor syndrome. There were six females and four males with a median age at the time of surgery of 42 (range from 20 to 58) years. Four shoulders were categorized as grade I (scapular dyskinesis), and six as grade II (intermittent brachial plexopathy). Shoulders were evaluated for pain, motion, satisfaction, subjective shoulder value (SSV), quick-DASH, ASES score, and complications. The mean follow-up time was 19 (range, 6 to 49) months.

Results

Arthroscopic release of the tendon of the Pm led to substantial resolution of pectoralis minor syndrome symptoms in all but one shoulder, which was considered a failure. Preoperatively, the median VAS for pain was 8.5 (range, 7–10) and the mean SSV was 20% (range, 10% - 50%). At most recent follow-up the mean VAS for pain was 1 (range, 0–6) and the mean SSV 80% (range, 50% - 90%). Before surgery, mean ASES and quick-DASH scores were 19.1 (range, 10–41.6) and 83.1 (range, 71 and 95.5) points respectively. At most recent follow-up, mean ASES and quick-DASH scores were 80.1 (range, 40–100) and 19.3 (range, 2.3–68) points respectively. No surgical complications occurred in any of the shoulder included in this study.

Conclusions

Endoscopic release of the tendon of the pectoralis minor from the coracoid improves pain, function and patient reported outcomes in the majority of patients presenting with the diagnosis of isolated pectoralis minor syndrome.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40634-022-00491-x.

Comprehensive supervised heavy training program versus home training regimen in patients with subacromial impingement syndrome: a randomized trial

Background

There is no consensus on the best training regimen for subacromial impingement syndrome (SIS). Several have been suggested, but never tested.

The purpose of the study is to compare a comprehensive supervised training regimen (STR) based on latest evidence including heavy slow resistance training with a validated home-based regimen (HTR). We hypothesized that the STR would be superior to the HTR.

Methods

Randomised control trial with blinded assessor. 126 consecutive patients with SIS were recruited and equally randomised to 12 weeks of either supervised training regimen (STR), or home-based training regimen (HTR). Primary outcomes were Constant Score (CS) and Shoulder Rating Questionnaire (SRQ) from baseline and 6 months after completed training. Results were analyzed according to intention-to treat principles. The study was retrospectively registered in ClinicalTrials.gov. Date of registration: 07/06/2021. Identification number: NCT04915430.

Results

CS improved by 22.7 points for the STR group and by 23,7 points for the HTR (p = 0.0001). The SRQ improved by 17.7 and 18.1 points for the STR and the HTR groups respectively (p = 0.0001). The inter-group changes were non-significant. All secondary outcomes (passive and active range of motion, pain on impingement test, and resisted muscle tests) improved in both groups, without significant inter-group difference.

Conclusion

We found no significant difference between a comprehensive supervised training regimen including heavy training principles, and a home-based training program in patients with SIS.

Low Risk of Fracture With End-Range Movements of the Hip in People With Low Bone Mineral Density: A Narrative Review

Background: The risks of end-range movements for people with osteoporosis, specifically at the hips and shoulder, are not well understood. Objectives: To synthesize literature on the safety of stretching for people with osteoporosis by searching: 1) biomechanical literature to determine how much force results from an end-range maneuverer and is required to fracture joint components (focusing on the hip joint) and 2) clinical literature to describe techniques used, populations studied, effects, and reported adverse events. Methods: We conducted two separate search strategies in PubMed, EMBASE, and Scopus (1955-2020). Results: 16 articles described either biomechanical or clinical effects of passive and active end ranges of the hip joint. The largest load in the hip, described in the literature was in a crescent lunge during yoga. The moment produced in a crescent lunge is much smaller than that of the tensile strength of osteoporotic bone, suggesting the crescent lunge movement could be considered safe. Clinically, no adverse events were reported in exercise, stretching or yoga interventions. Conclusion: This review found no evidence that end range movements of the hip are unsafe, but there is little evidence. No studies were identified that explored the risk of humeral fracture during end range stretches.

Is the Disabilities of the Arm, Shoulder and Hand (DASH) Questionnaire Adequate to Assess Individuals With Subacromial Pain Syndrome? Rasch Model and International Classification of Functioning, Disability and Health

OBJECTIVE

The Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire is widely used to assess patients with symptoms of subacromial pain syndrome (SPS). No study has analyzed the DASH by using the Rasch model in these patients and related the level of difficulty of the items with the International Classification of Functioning Disability and Health (ICF) domains. The purpose of this study was to evaluate the measurement properties of the DASH in individuals with SPS and to describe which ICF components are influenced by SPS based on the DASH.

METHODS

The full version of the DASH was used to assess upper limb pain and function in individuals with SPS. Responses were assessed using the Rasch model. DASH items were grouped according to the level of difficulty and associated with the ICF domains to identify the most compromised aspect in these individuals.

RESULTS

Reliability and internal consistency for the DASH were shown to be 0.93 and 0.95, respectively. Item 3 ("Turn a key") was the easiest and 25 ("Pain during specific activity") the most difficult. Only item 30 ("Less capable/confident/useful") was as an erratic item. Item 15 ("Put on a sweater") showed differential functioning by age and item 11 ("Carry a heavy object") by sex. Seven items showed differential functioning related to the angular onset of pain during arm elevation. Sixty percent of the most difficult items belonged to the "Body function" domain of the ICF.

CONCLUSION

Although some psychometric properties of the DASH are adequate according to the Rasch model, adjustments to some items are necessary for individuals with SPS. Clinicians should be cautious when interpreting the DASH, especially in patients with angular onset of pain above 120 degrees of arm elevation.

IMPACT

The information contained in this study should be used by clinicians to interpret the results of the DASH when assessing individuals with SPS. The DASH may not be adequate to assess those with shoulder pain above 120 degrees of arm elevation. These results are not generalizable to other shoulder pathologies.

Comparison of specific and non-specific treatment approaches for individuals with posterior capsule tightness and shoulder impingement symptoms: A randomized controlled trial

BACKGROUND

Posterior capsule tightness (PCT) is associated with shoulder pain and altered shoulder kinematics, range of motion (ROM), external rotation (ER) strength, and pain sensitization.

OBJECTIVE

To assess the effects of two interventions on shoulder kinematics, Shoulder Pain and Disability Index (SPADI) scores, ROM, strength, and pressure pain threshold (PPT) in individuals with PCT and shoulder impingement symptoms.

METHODS

In this prospectively registered randomized controlled trial 59 individuals were randomized to either an Experimental Intervention Group (EIG, n=31) or a Control Intervention Group (CIG, n=28). The low flexion (LF) test was used to determine the presence of PCT. Shoulder kinematics, SPADI scores, internal rotation (IR) and ER ROM, ER strength, and PPT were measured pre- and post-treatment. Those in the EIG received an intervention specific to pain and PCT and those in the CIG received a non-specific intervention, both 4 weeks in duration.

RESULTS

Individuals in the EIG demonstrated more scapular upward rotation (P=.03; mean difference (MD)=3.3°; 95% Confidence Interval (CI)=1.3°, 4.9°) and improved value on the LF test (P=.02; MD=4.6°; 95%CI=0.7°, 8.6°) than those in the CIG after treatment. Both groups presented less anterior (P<.01; MD=-0.7mm; 95%CI=-1.3mm, -0.2mm) and superior (P<.01; MD=-0.5mm; 95%CI=-0.9mm, -0.2mm) humeral translations, decreased SPADI score (P<.01; MD=-23.6; 95%CI=-28.7, -18.4), increased IR ROM (P<.01; MD=4.6°; 95%CI=1.8°, 7.8°) and PPTs for upper trapezius (P<.01; MD=60.1kPa; 95%CI=29.3kPa, 90.9kPa), infraspinatus (P=.04; MD=47.3kPa; 95%CI=2.1kPa, 92.5kPa), supraspinatus (P<.01; MD=63.7kPa; 95%CI=29.6kPa, 97.9kPa), and deltoid (P<.01; MD=40.9kPa; 95%CI=12.3kPa, 69.4kPa) after treatment.

CONCLUSION

The experimental intervention was more effective at improving PCT as measured through changes in the LF test. No benefit of the specific approach over the non-specific intervention was noted for the remaining variables.

Acute and Prolonged Effects of Stretching on Shear Modulus of the Pectoralis Minor Muscle

Increased muscle stiffness of the pectoralis minor (PMi) could deteriorate shoulder function. Stretching is useful for maintaining and improving muscle stiffness in rehabilitation and sport practice. However, the acute and prolonged effect of stretching on the PMi muscle stiffness is unclear due to limited methodology for assessing individual muscle stiffness. Using shear wave elastography, we explored the responses of shear modulus to stretching in the PMi over time. The first experiment (n = 20) aimed to clarify the acute change in the shear modulus during stretching. The shear modulus was measured at intervals of 30 s × 10 sets. The second experiment (n = 16) aimed to observe and compare the prolonged effect of different durations of stretching on the shear modulus. Short and long stretching duration groups underwent 30s × 1 set and 30s × 10 sets, respectively. The assessments of shear modulus were conducted before, immediately after, and at 5, 10, and 15 min post-stretching. In experiment I, the shear modulus decreased immediately after a bout (30 s) of stretching (p < 0.001, change: -2.3 kPa, effect size: r = 0.72) and further decreased after 3 repetitions (i.e., 90 s) of stretching (p = 0.03, change: -1.0 kPa, effect size: r = 0.53). In experiment II, the change in the shear modulus after stretching was greater in the long duration group than in the short duration group (p = 0.013, group mean difference: -2.5 kPa, partial η ² = 0.36). The shear modulus of PMi decreased immediately after stretching, and stretching for a long duration was promising to maintain the decreased shear modulus. The acute and prolonged effects on the PMi shear modulus provide information relevant to minimum and persistent stretching time in rehabilitation and sport practice.

Scapular movement training versus standardized exercises for individuals with chronic shoulder pain: protocol for a randomized controlled trial

BACKGROUND

Scapular focused exercise interventions are frequently used to treat individuals with shoulder pain. However, evidence for changes in scapular motion after intervention is limited.

OBJECTIVE

To compare the effects of scapular movement training versus standardized exercises for individuals with shoulder pain.

METHODS

This will be a single-blinded randomized controlled trial. Sixty-four individuals with shoulder pain for at least 3 months, scapular dyskinesis, and a positive scapular assistance test will be randomly allocated to one of two groups: Scapular Movement Training (group 1) and Standardized Exercises (group 2). Group 1 will receive education about scapular position and movement, and be trained to modify the scapular movement pattern. Group 2 will perform stretching and strengthening exercises. Both groups will be treated twice a week for eight weeks. Three-dimensional scapular kinematics and muscle activity of the serratus anterior and upper, middle, and lower trapezius during elevation and lowering of the arm will be assessed at baseline and after 8 weeks of treatment. Pain intensity, function, fear avoidance beliefs, and kinesiophobia will be assessed at baseline and after 4 and 8 weeks of treatment, and 4 weeks after the end of treatment.

CONCLUSIONS

The results of this study may contribute to a better understanding of the efficacy of scapular focused treatments for individuals with shoulder pain.

CLINICAL TRIAL REGISTRATION

NCT03528499.

Pain and its impact on functioning and disability in manual wheelchair users with spinal cord injury: a protocol for a mixed-methods study

INTRODUCTION

Approximately 80% of people with spinal cord injury experience clinically significant chronic pain. Pain (whether musculoskeletal or neuropathic) is consistently rated as one of the most difficult problems to manage and negatively affects the individual's physical, psychological and social functioning and increases the risk of pain medication misuse and poor mental health. The aim of this study is to therefore determine the presence of pain and its impact on functioning and disability as well as to develop a framework for self-management of pain for South African manual wheelchair users with spinal cord injury.

METHODS AND ANALYSIS

Community-dwelling participants with spinal cord injury will be invited to participate in this three-phase study. Phase 1 will use a quantitative, correlational design to determine factors related to pain such as pectoralis minor length, scapular dyskinesis, wheelchair functioning, physical quality of life, community reintegration and pain medication misuse. Demographic determinants of pain such as age, gender, type of occupation, completeness of injury and neurological level of injury will also be investigated. Participants with pain identified in phase 1 will be invited to partake in a qualitative descriptive and contextually designed phase 2 to explore their lived experience of pain through in-depth interviews. The results of phases 1 and 2 will then be used with the assistance from experts to develop a framework for self-management of pain using a modified Delphi study. Data analysis will include descriptive and inferential statistics (quantitative data) and thematic content analysis (qualitative data).

ETHICS AND DISSEMINATION

Approval for this study is granted by the Faculty of Health Sciences Research Ethics Committee of the University of the Pretoria (approval number 125/2018). This study is registered with the South African National Health Research Database (reference GP201806005). This study's findings will be shared in academic conferences and published in scientific peer-reviewed journals.

Pectoralis minor length measurements in three different scapula positions

Background

The pectoralis minor (PM) muscle is commonly regarded as a contributor to abnormal scapula positioning. Subsequently, the muscle length of the scapular stabilising muscles may be affected, as these muscles assume a lengthened position, which over time causes weakness. There are inconsistencies regarding PM muscle length values because of the different techniques and positions used when the length of the PM muscle is measured.

Objective

To determine the PM muscle length in participants aged 18−24 using a Vernier^® caliper and expressed as pectoralis minor index (PMI), with the scapula in three different positions.

Method

The PM muscle length of 144 participants was measured with a Vernier^® caliper (intraclass correlation coefficient 0.83−0.87). Measurements were made with the scapula in the resting position, in an active and a passive posterior tilt position.

Results

Significant differences were observed in PMI between the resting scapula position – 10.04 (confidence interval, CI 9.93–10.14) and active posterior tilt – 10.19 (CI 10.09–10.30) (p < 0.001); the resting position – 10.04 (CI 9.93–10.14) and passive posterior tilt – 10.77 (10.66–10.87) (p < 0.001) and active – 10.19 (CI 10.09–10.30) and passive posterior tilt 10.77 (10.66–10.87) (p < 0.001). The dominant side had lower PMI values than the non-dominant side.

Conclusion

The significant differences between the active and posterior tilt positions suggested that optimal muscle length of PM was affected by the inner range strength of the lower fibres of Trapezius.

Clinical implications

It is important that in clinical practice not only the length of PM in scapular misalignment but also the strength of the antagonistic muscles is considered.

Association of Both Scapular Upward Rotation and Scapulothoracic Muscle Lengths With Shoulder Pain, Function, and Range of Movement

OBJECTIVE

Our aim was to analyze whether shoulder pain is related to scapular upward rotation (SUR) or to the lengths of the pectoralis minor and levator scapulae muscles.

METHODS

This cross-sectional, observational study was carried out in 3 primary-care centers; 54 individuals with chronic shoulder pain participated. Scapular upward rotation and the lengths of the pectoralis minor and levator scapulae muscles were assessed.

RESULTS

The level of association was small between shoulder pain and function and (1) the lengths of the pectoralis minor (r = 0.08, P = .93) and levator scapulae (r = -0.01, P = .57) muscles and (2) SUR at 45° (r = 0.17, P = .21), 90° (r = 0.08, P = .57), and 135° (r = 0.10, P = 0.45) of shoulder elevation.

CONCLUSION

The relationship was small between shoulder pain and function and (1) SUR (45°, 90°, and 135° of shoulder elevation) and (2) the lengths of the pectoralis minor and levator scapulae muscles. Thus, the use of SUR and pectoralis minor and levator scapulae lengths in shoulder assessment should be undertaken with caution. Other factors such as psychological factors, central/peripheral sensitization, and intrinsic properties of the tissue have to be taken into account.

Predictors of throwing performance in amateur male cricketers: A musculoskeletal approach

Optimal throwing speed and accuracy is built on a complex interaction of multiple variables. Although strength and power has been associated with throwing speed in cricketers, the individual muscles that contribute to optimal function of the shoulder-complex has not been adequately explored in connection with throwing performance. Consequently, this study aimed to investigate the correlation between musculoskeletal variables and overhead throwing performance in cricketers. Thirty-two amateur male cricketers were tested using a battery of 16 tests (strength, flexibility, scapula positioning) as well as a throwing speed (TS) and a novel accuracy test (TA). Only two of the sixteen tests were correlated with throwing performance in the multiple regression analysis. Non-dominant hip abduction strength correlated positively with TS (p < 0.05): on average, a strength increase of 10 newtons (N) was associated with an increase in TS of 0.60 km/h (95% CI: 0.12-1.08). Non-dominant pectoralis minor length correlated positively with TA (p < 0.01): on average, a one-centimetre increase in the length correlated to an increase, of 0.633 points (95% CI: 0.225-1.041). This cross-sectional study demonstrated that from an array of musculoskeletal variables, only non-dominant hip abduction strength correlated with TS, while only non-dominant pectoralis minor length correlated with TA in amateur cricketers.

Comparison of scapular kinematics and muscle strength between those with a positive and a negative Scapular Assistance Test

BACKGROUND

The Scapular Assistance Test was suggested to directly assess the influence of scapular motion on pain and indirectly measure the function of the scapular rotators. However, it is still not clear if individuals with a positive Scapular Assistance Test actually present changes in scapular motion and muscle strength. This study compared scapular kinematics and muscle strength between those with a positive Scapular Assistance Test and those with a negative Scapular Assistance Test.

METHODS

Fifty individuals with shoulder pain were randomly allocated to: positive (n = 25) or negative Scapular Assistance Test (n = 25) group. Scapular kinematics was measured during elevation and lowering of the arm. Strength of the serratus anterior and lower trapezius was also measured. Two-way analysis of variance was used to compare kinematics between groups. Unpaired Student's t-test and Mann-Whitney test were used to compare strength of serratus anterior and lower trapezius, respectively.

FINDINGS

There were no differences (P > 0.05) in scapular internal rotation and upward rotation between both groups. For scapular tilt, there was group main effect (P < 0.05) during elevation and lowering of the arm, whereas the positive Scapular Assistance Test group presented greater scapular anterior tilt. There was no difference (P > 0.05) in strength between groups.

INTERPRETATION

Individuals with a positive Scapular Assistance Test are more likely to present decreased scapular posterior tilt in those with shoulder pain. Strength of the scapular muscles seems to be same in those with a positive and a negative Scapular Assistance Test.

Comparison of Myofascial Release Techniques on Pectoralis Minor Length, Glenohumeral Total Arc of Motion, and Skin Temperature: A Pilot Study

CONTEXT

The pectoralis minor (PM) is an important postural muscle that may benefit from myofascial techniques, such as Graston Technique® (GT) and self-myofascial release (SMR).

OBJECTIVE

To examine the effects of GT and SMR on PM length, glenohumeral total arc of motion (TAM), and skin temperature.

DESIGN

Cohort.

SETTING

Laboratory.

PARTICIPANTS

Twenty-six healthy participants (19 females and 7 males; age = 20.9 [2.24] y, height = 170.52 [8.66] cm, and weight = 72.45 [12.32] kg) with PM length restriction participated.

INTERVENTIONS

Participants were randomized to the intervention groups (GT = 12 and SMR = 14). GT and SMR interventions were both applied for a total of 5 minutes during each of the 3 treatment sessions.

MAIN OUTCOME MEASURES

PM length, TAM, and skin temperature were collected before and after each intervention session (Pre1, Post1, Pre2, Post2, Pre3, and Post3) and at 1-week follow-up (follow-up). Separate intervention by time analyses of variance examined differences for each outcomes measure. Bonferroni post hoc analyses were completed when indicated. Significance was set a priori at P ≤ .05.

RESULTS

No significant intervention by time interactions were identified for PM length, TAM, or temperature (P > .05). No significant intervention main effects were identified for PM length (P > .05), TAM (P > .05), or temperature (P > .05) between the GT or SMR technique groups. Overall, time main effects were found for PM length (P = .02) and temperature (P < .001). Post hoc analysis showed a significant increase in PM length for both intervention groups at follow-up (P = .03) compared with Post2. Furthermore, there were significant increases in temperature at Post1 (P < .001), Post2 (P = .01), and Post3 (P < .001) compared with Pre1; Post2 was increased compared with Pre2 (P = .003), Pre3 (P < .001), and follow-up (P = .01); Post3 increased compared with Pre3 (P = .01) and follow-up (P = .01).

CONCLUSION

Serial application of GT and SMR to the PM did not result in increases in PM length or TAM. Regardless of intervention, skin temperature increased following each intervention.

Exercise therapy may affect scapular position and motion in individuals with scapular dyskinesis: a systematic review of clinical trials

BACKGROUND

Therapeutic exercise for scapular muscles is suggested to be effective in reducing shoulder pain in patients with rotator cuff disorders, whereas its effectiveness on scapular position and motion has remained unclear. Therefore, the aim of this systematic review was to investigate whether exercise therapy improves scapular position and motion in individuals with scapular dyskinesis.

METHODS

This study is a wide systematic review including any type of clinical trial in which the effect of any type of therapeutic exercise, including scapular muscle strengthening, stretching, and scapular stabilization exercise, is investigated in adult participants.

RESULTS

Twenty studies were included in this systematic review. Studies were categorized on the basis of the techniques they used to measure scapular position and motion and the included participants. Methodologic quality of the studies was assessed by the Cochrane tool of assessing the risk of bias. Eight studies used 3-dimensional techniques for measuring scapular motions. Among them, 5 studies showed significant effects of exercise on scapular motion, of which 3 studies investigated individuals with subacromial impingement syndrome (SIS). The other 12 studies used 2-dimensional measurement techniques, of which 8 studies reported significant effects of exercise on scapular position and motion both in SIS patients and in asymptomatic individuals. However, their methodologic quality was debatable. Therefore, there was conflicting evidence for the effect of exercise on scapular dyskinesis.

CONCLUSION

There is a lack of evidence for beneficial effects of exercise in improving scapular position and motion in individuals with scapular dyskinesis. However, exercise is beneficial in reducing pain and disability in individuals with SIS.

The interaction between pain and movement

STUDY DESIGN

Clinical commentary.

INTRODUCTION/PURPOSE

Pain and movement are universally relevant phenomena that influence human experiences in readily observable ways. Improved understanding of pain-movement relationships can guide medical and rehabilitative approaches to recovery and decrease risk of dysfunctional long-term consequences of otherwise normal neuromuscular responses. Therefore, the overall intent of this article is to elucidate the relationships between pain and movement as they relate to clinical decision making.

CONCLUSIONS

Motor output is highly adaptable, can be influenced by multiple mechanisms at various levels along the nervous system, and may vary between individuals despite similar diagnoses. Therefore, interventions need to be individualized and consider both the types of motor response observed (ie, whether the response is protective or maladaptive), and the patient's acute physical activity tolerance when prescribing exercise/movement.

Does pectoralis minor stretching provide additional benefit over an exercise program in participants with subacromial pain syndrome? A randomized controlled trial

BACKGROUND

Adaptive shortening of the pectoralis minor is one of the biomechanical mechanisms associated with subacromial pain syndrome (SPS).

OBJECTIVE

To compare the effects of an exercise program alone with an exercise program in combination with pectoralis minor stretching in participants with SPS.

DESIGN

Randomized controlled trial.

METHODS

Eighty adult participants with SPS were randomly allocated to two groups. The control group (n = 40) received a 12-week specific exercise program and the intervention group (n = 40) received the same program plus stretching exercises of the pectoralis minor muscle. The primary outcome measure was shoulder function assessed by a Constant-Murley questionnaire, and the secondary outcomes were the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, visual analog scale (VAS), and pectoralis minor resting length.

RESULTS

The present study shows no difference between the two interventions according to the Constant-Murley questionnaire (1.5 points; p = 0.58), VAS at rest (0.2 cm; p = 0.11), VAS at movement (0.5 cm; p = 0.08), and pectoralis minor resting length (0.3 cm; p = 0.06). The DASH questionnaire showed greater functional improvement in the control group (5.4 points; p = 0.02). Finally, only pectoralis minor length index showed difference statistical significant in favor of intervention group (0.3%; p = 0.04).

CONCLUSION

In the short-term, the addition of a program of stretching exercises of the pectoralis minor does not provide significant clinical benefit with respect to functional improvement or pain reduction in participants with SPS.

TRIAL REGISTRATION

Brazilian registry of clinical trials UTN number U1111-1210-3555. Registered 5 March 2018.

Acute Effects of Pectoralis Minor Self-Mobilization on Shoulder Motion and Posture: A Blinded and Randomized Placebo-Controlled Study in Asymptomatic Individuals

CONTEXT

Tightness of the pectoralis minor is a common characteristic that has been associated with aberrant posture and shoulder pathology. Determining conservative treatment techniques for maintaining and lengthening this muscle is critical. Although some gross stretching techniques have been proven effective, there are currently no empirical data regarding the effectiveness of self-myofascial release for treating tightness of this muscle.

OBJECTIVE

To determine the acute effectiveness of a self-myofascial release with movement technique of the pectoralis minor for improving shoulder motion and posture among asymptomatic individuals.

DESIGN

Randomized controlled trial.

SETTING

Orthopedic rehabilitation clinic.

PARTICIPANTS

A total of 21 physically active, college-aged individuals without shoulder pain volunteered to participate in this study.

MAIN OUTCOME MEASURES

Glenohumeral internal rotation, external rotation, and flexion range of motion (ROM), pectoralis minor length, and forward scapular posture were measured in all participants. The intervention group received one application of a self-soft-tissue mobilization of the pectoralis minor with movement. The placebo group completed the same motions as the intervention group, but with minimal pressure applied to the xiphoid process. Separate analyses of covariance were used to determine differences between groups (P < .05).

RESULTS

Separate analyses of covariance showed that the self-mobilization group had significantly more flexion ROM, pectoralis minor length, and less forward scapular posture posttest than the placebo group. However, the difference in forward scapular posture may not be clinically significant. No differences were found between groups for external or internal rotation ROM.

CONCLUSIONS

The results of this study indicate that an acute self-myofascial release with movement is effective for improving glenohumeral flexion ROM and pectoralis minor length, and may assist with forward scapular posture. Clinicians should consider this self-mobilization in the prevention and rehabilitation of pathologies associated with shortness of the pectoralis minor.

Rehabilitation and Prehabilitation for Upper Extremity in Throwing Sports: Emphasis on Lacrosse

Lacrosse imposes multiple simultaneous physical demands during play including throwing and catching a ball while holding a crosse, running, cutting, and jumping. Often, these skills are completed while experiencing contact from another player leading to both on-and-off platform movements. Other motions include defensive blocking and pushing past defenders. Repetitive motions over sustained durations in practice or competition impart mechanical stresses to the shoulder or elbow joints, supportive muscles, and connective tissue. Preparation for lacrosse participation involves bilateral optimization of strength and durability of stabilizer muscles. Passing and shooting skills are encouraged to be equally effective on both sides; therefore, symmetric strength and flexibility are vital for prehabilitation and rehabilitation efforts. This article will: 1) provide insights on the upper-extremity musculoskeletal demands of lacrosse and related sports with similar throwing motion and 2) describe prehabilitation and rehabilitation methods that improve athlete durability and reduce likelihood of upper-extremity injury.

Effectiveness of stretching exercise versus kinesiotaping in improving length of the pectoralis minor: A systematic review and network meta-analysis

OBJECTIVE

Shortness of the pectoralis minor (PM) is a potential mechanism underlying shoulder impingement syndrome. Few studies have examined the effects of kinesiotaping and stretching exercise on PM length or index. This systematic review and network meta-analysis investigated the effects of stretching exercise and kinesiotaping on PM length and index in adults.

METHODS

This study followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Randomised controlled trials including adults with or without symptomatic shoulders were included. Heterogeneity between studies was assessed using I2 statistics, and publication bias was evaluated by constructing a funnel plot.

RESULTS

We extracted data from six randomised controlled trials that included 263 participants (age range: 18-50 years). Compared with usual care, kinesiotaping resulted in greater improvement in PM length (mean difference, 1.15 cm; 95% confidence interval [CI]: 0.20-2.10 cm). Compared with usual care and kinesiotaping, proprioceptive neuromuscular facilitation (PNF) stretching increased PMI significantly, with a mean difference of 1.40 (95% CI: 1.17-1.63) and 1.08 (95% CI: 0.29-1.87) cm, respectively.

CONCLUSION

Compared with no intervention, kinesiotaping is beneficial for lengthening the PM. Intervention with static stretching alone has no effect on PM length. Compared with kinesiotaping alone and no intervention, PNF stretching increases PMI.

The Influence of Glenohumeral Joint Posterior Capsule Tightness and Impingement Symptoms on Shoulder Impairments and Kinematics

BACKGROUND

Posterior capsule tightness (PCT) and shoulder impingement syndrome (SIS) symptoms are both associated with altered shoulder biomechanics and impairments. However, their combined effect on kinematics, pain, range of motion (ROM), strength, and function remain unknown.

OBJECTIVE

The purpose of this study was to determine if the combination of PCT and SIS affects scapular and humeral kinematics, glenohumeral joint ROM, glenohumeral joint external rotation strength, pain, and function differently than does either factor (PCT or SIS) alone.

DESIGN

The design was a cross-sectional group comparison.

METHODS

Participants were placed into 1 of 4 groups based on the presence or absence of SIS and PCT: control group (n = 28), PCT group (n = 27), SIS group (n = 25), and SIS + PCT group (n = 25). Scapular kinematics and humeral translations were quantified with an electromagnetic motion capture system. Shoulder internal rotation and external rotation ROM, external rotation strength, and pain and Shoulder Pain and Disabilities Index scores were compared between groups with ANOVA.

RESULTS

The SIS group had greater scapular internal rotation (mean difference = 5.13°; 95% confidence interval [CI] = 1.53°-8.9°) and less humeral anterior translation (1.71 mm; 95% CI = 0.53-2.9 mm) than the other groups. Groups without PCT had greater internal rotation ROM (16.05°; 95% CI = 5.09°-28.28°). The SIS + PCT group had lower pain thresholds at the levator scapulae muscle (108.02 kPa; 95% CI = 30.15-185.88 kPa) and the highest Shoulder Pain and Disabilities Index score (∼ 44.52; 95% CI = 33.41-55.63).

LIMITATIONS

These results may be limited to individuals with impingement symptoms and cannot be generalized to other shoulder conditions.

CONCLUSIONS

Decreased ROM and lower pain thresholds were found in individuals with both impingement symptoms and PCT. However, the combination of factors did not influence scapular and humeral kinematics.

Differences in scapular upward rotation, pectoralis minor and levator scapulae muscle length between the symptomatic, the contralateral asymptomatic shoulder and control subjects: a cross-sectional study in a Spanish primary care setting

OBJECTIVE

To determine the potential differences in both scapular positioning and scapular movement between the symptomatic and asymptomatic contralateral shoulder, in patients with unilateral subacromial pain syndrome (SAPS), and when compared with participants free of shoulder pain.

SETTING

Three different primary care centres.

PARTICIPANTS

A sample of 73 patients with SAPS in their dominant arm was recruited, with a final sample size of 54 participants.

PRIMARY OUTCOME MEASURES

The scapular upward rotation (SUR), the pectoralis minor and the levator scapulae muscles length tests were carried out.

RESULTS

When symptomatic shoulders and controls were compared, an increased SUR at all positions (45°, 90° and 135°) was obtained in symptomatic shoulders (2/3,98/8,96°, respectively). These differences in SUR surpassed the minimal detectable change (MDC95) (0,91/1,55/2,83° at 45/90/135° of shoulder elevation). No differences were found in SUR between symptomatic and contralateral shoulders. No differences were found in either pectoralis minor or levator scapulae muscle length in all groups.

CONCLUSIONS

SUR was greater in patients with chronic SAPS compared with controls at different angles of shoulder elevation.

Influence of reducing anterior pelvic tilt on shoulder posture and the electromyographic activity of scapular upward rotators

BACKGROUND

Modifications of posture in a segment may influence the posture of adjacent and nonadjacent segments and muscular activity. The spine-shoulder and spine-pelvis relationships suggest that the pelvis may influence shoulder posture.

OBJECTIVE

To investigate the effect of the active reduction of the anterior pelvic tilt on shoulder and trunk posture during static standing posture and on the electromyographic activity of the scapular upward rotators during elevation and lowering of the arm.

METHODS

Thirty-one young adults were assessed in a relaxed standing position and a standing position with 30% active reduction of the anterior pelvic tilt. The pelvic tilt, trunk posture, and forward shoulder posture during the static standing posture and the electromyographic activity during elevation and lowering of the arm were assessed.

RESULTS

Paired t-tests indicated that the active reduction of the anterior pelvic tilt reduced the trunk extension (MD=1.09; 95%CI=-2.79 to -1.03). There were no effects on the forward shoulder posture (MD=0.09; 95%CI=-0.92 to 1.09). Repeated measures of analyses of variance indicated an increase in lower trapezius electromyographic activity (MD=3.6; 95%CI=1.28 to 5.92). There was a greater reduction in upper trapezius activity after pelvic tilt reduction during arm elevation (MD=1.52%; 95%CI=-2.79 to -0.25) compared to that during the lowering phase. There were no effects of pelvic tilt reduction on the electromyographic activity of the serratus anterior (MD=3.26; 95%CI=-3.36 to 9.87).

CONCLUSION

The influence of pelvic posture on the trunk posture and lower trapezius activation should be considered when assessing or planning exercise for individuals with shoulder or trunk conditions.

Scapular kinematic alterations during arm elevation with decrease in pectoralis minor stiffness after stretching in healthy individuals

BACKGROUND

Pectoralis minor tightness may be seen in individuals with scapular dyskinesis, and stretching is used for the treatment of altered scapular motion in sports and clinical fields. However, few researchers have reported on the effects of pectoralis minor stiffness on scapular motion during arm elevation. This study investigated whether an acute decrease of pectoralis minor stiffness after stretching changes the scapular motion during arm elevation.

METHODS

The study allocated 15 dominant and 15 nondominant upper limbs in healthy men as control and interventional limbs, respectively. In the intervention limb group, the shoulder was passively and horizontally abducted at 150° of elevation for 5 minutes to stretch the pectoralis minor muscle. Before and after stretching, an electromagnetic sensor was used to examine 3-dimensional scapular motion during abduction and scaption. Ultrasonic shear wave elastography was used to measure pectoralis minor stiffness before and immediately after stretching and after arm elevation.

RESULTS

In the interventional limb, pectoralis minor stiffness decreased by 3.2 kPa immediately after stretching and by 2.5 kPa after arm elevation. The maximal changes in scapular kinematics after stretching were 4.8° of external rotation and 3.3° of posterior tilt in abduction, and 4.5° of external rotation and 3.7° of posterior tilt in scaption. Upward rotation in abduction or scaption did not change.

CONCLUSIONS

Stretching for the pectoralis minor muscle increases external rotation and posterior tilt of the scapula during arm elevation.

Pectoralis minor muscle elongation and scapulothoracic motion do not differ in individuals with short versus typical resting pectoralis minor muscle length: a cross-sectional study

BACKGROUND

Individuals with short resting pectoralis minor muscle length have been shown to have aberrant scapulothoracic motion when compared to individuals with long resting pectoralis minor muscle length. However, the degree to which the pectoralis minor muscle can be lengthened and whether or not scapulothoracic motion differs between individuals with short and typical resting pectoralis minor muscle length is unknown.

OBJECTIVES

To determine if: (1) pectoralis minor muscle elongation (percent pectoralis minor muscle can be actively and passively lengthened beyond resting length), (2) pectoralis minor muscle percent length change during overhead reaching, and (3) scapulothoracic motion during overhead reaching differ between individuals with short and typical resting pectoralis minor muscle length.

DESIGN

Two group comparison.

METHODS

Thirty healthy individuals were placed into a short or typical resting pectoralis minor muscle length group. A caliper was used to measure resting pectoralis minor muscle length and pectoralis minor muscle length during active and passive muscle lengthening. An electromagnetic tracking system was used to measure pectoralis minor muscle length change as well as scapular, humeral, and trunk motion during several arm elevation tasks. Pectoralis minor muscle elongation and length change during arm elevation tasks were compared between groups using independent t-tests. Two-factor mixed-model analyses of variance were used to compare scapulothoracic motion at arm elevation angles of 30°, 60°, 90°, and 120°.

RESULTS

Pectoralis minor muscle elongation and pectoralis minor muscle length change during arm elevation did not differ between groups. Scapulothoracic motion did not differ between groups across arm elevation tasks.

CONCLUSIONS

Although resting pectoralis minor muscle length differed between groups, pectoralis minor muscle lengthening and scapulothoracic motion were similar between participants with short and typical resting pectoralis minor muscle length. Additional studies are needed to better understand the role of pectoralis minor muscle elongation on scapulothoracic motion.

The effects of shoulder stabilization exercises and pectoralis minor stretching on balance and maximal shoulder muscle strength of healthy young adults with round shoulder posture

[Purpose] The purpose of this study was to analyze the effects of pectoralis minor stretching and shoulder strengthening with an elastic band on balance and maximal shoulder muscle strength in young adults with rounded shoulder posture. [Subjects and Methods] Nineteen subjects with rounded shoulder posture were randomly divided into 2 groups: a shoulder stabilization exercise group and a stretching exercise group. The groups performed each exercise for 40 minutes, 3 times a week, for 4 weeks. Static balance (eyes open and closed), dynamic balance (the limits of stability in 4 directions) and shoulder muscle strength in 5 directions were measure before and after the exercises. [Results] The stretching exercise demonstrated a significant difference between the pre- and post-exercise in the static balance with eyes closed and extension and horizontal abduction strength while the stabilization exercise demonstrated significant difference in the left and right directions between the pre- and post-exercise of the dynamic balance and flexion strength. The stabilization exercise demonstrated significant differences shown in the flexion between the pre- and post-test. [Conclusion] The shoulder stabilization and stretching exercises improved the static balance, dynamic balance, and muscle strength.

Association of Pectoralis Minor Muscle Extensibility, Shoulder Mobility, and Duration of Manual Wheelchair Use

OBJECTIVE

To assess the relation of pectoralis minor muscle (PMm) length and extensibility to shoulder pain, shoulder girdle motion, and duration of manual wheelchair (MWC) use, and to compare differences in muscle length, muscle extensibility, peak humeral elevation, and pain among groups based on duration of wheelchair use.

DESIGN

Cross-sectional cohort study.

SETTING

Laboratory setting.

PARTICIPANTS

Individuals with spinal cord injury (SCI) who used an MWC for daily community and home mobility (N=22; 18 men; mean age, 41.7y; duration wheelchair use, 14.6y). Participants were stratified into groups based on duration of wheelchair use: <5 years (n=6), 5 to 15 years (n=8), and >15 years (n=8).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Clinical measures of PMm length and extensibility, shoulder girdle motion, and shoulder pain (Wheelchair User's Shoulder Pain Index).

RESULTS

Significant high correlations were found among duration of wheelchair use, passive PMm length, passive PMm extensibility, and peak humerothoracic elevation. Moderate correlation of peak humerothoracic elevation to pain was found. Individuals with >15 years wheelchair use had reduced PMm extensibility and reduced peak humerothoracic elevation than those with <5 years duration of use.

CONCLUSIONS

To our knowledge, this is the first investigation to identify the association of reduced PMm extensibility with reduced shoulder girdle mobility, pain, and duration of wheelchair use in individuals with SCI.