Scapular-focused exercise treatment protocol for shoulder impingement symptoms: Three-dimensional scapular kinematics analysis

Efficacy of Targeted Scapular Stabilization Exercise Versus Conventional Exercise for Patients With Shoulder Pain: A Randomized Clinical Trial

OBJECTIVE

The aim of the study is to investigate the efficacy of targeted scapular stabilization exercise in shoulder pain.

DESIGN

This is an evaluator-blinded, multicenter, randomized controlled trial. The scapular stabilization exercise group ( n = 45) received scapular stabilization exercise based on the type of scapular dyskinesis for 6 wks; the conventional exercise group ( n = 45) received pendulum, wall climbing and stick exercises for 6 wks. Constant-Murley score, numerical rating scale, range of motion, type of scapular dyskinesis, lateral scapular sliding test, pectoralis minor index, scapular index, and satisfaction were assessed at baseline, 2-, 4-, and 6-wk treatment as well as a 6-wk follow-up.

RESULTS

After a 6-wk intervention, the improvement of Constant-Murley score was greater in the scapular stabilization exercise group than in the conventional exercise group, and improvement continued at the 6-wk follow-up ( F = 15.39, P < 0.001, partial η 2 = 0.17). The results were also significant for numerical rating scale during activity, lateral scapular sliding test, pectoralis minor index, type of scapular dyskinesis, and satisfaction in favor of the scapular stabilization exercise group ( P < 0.05).

CONCLUSIONS

Targeted scapular stabilization exercise is an effective intervention program that might be applied to the rehabilitation of shoulder pain.

Scapula-Focused Exercises With or Without Biofeedback and Corticospinal Excitability in Recreational Overhead Athletes With Shoulder Impingement

CONTEXT

Individuals with shoulder impingement syndrome (SIS) exhibit changes in corticospinal excitability, scapular kinematics, and scapular muscle-activation patterns. To restore the scapular kinematics and muscle-activation patterns in individuals with SIS, treatment protocols usually include scapula-focused exercises, such as scapular-orientation and strength training.

OBJECTIVE

To investigate whether scapular-orientation and strength training can reverse the altered corticospinal excitability of recreational overhead athletes with SIS.

DESIGN

Randomized controlled clinical trial.

SETTING

University laboratory.

PATIENTS OR OTHER PARTICIPANTS

Forty-one recreational overhead athletes with SIS: 20 in the scapular-orientation group (age = 26.45 ± 4.13 years, height = 171.85 ± 7.88 cm, mass = 66.70 ± 10.68 kg) and 21 in the strengthening group (age = 26.43 ± 5.55 years, height = 171.62 ± 5.87 cm, mass = 68.67 ± 10.18 kg).

INTERVENTION(S)

Both groups performed a 30-minute training protocol consisting of 3 exercises to strengthen the lower trapezius (LT) and serratus anterior muscles without overactivating the upper trapezius muscles. Participants in the scapular-orientation group were instructed to consciously activate their scapular muscles with electromyographic biofeedback and cues, whereas the strengthening group did not receive biofeedback or cues for scapular motion.

MAIN OUTCOME MEASURE(S)

Corticospinal excitability was assessed using transcranial magnetic stimulation. Scapular kinematics and muscle activation during arm elevation were also measured.

RESULTS

After training, both groups demonstrated an increase in motor-evoked potentials in the LT (P = .004) and increases in scapular upward rotation (P = .03), LT activation (P < .001), and serratus anterior activation (P < .001) during arm elevation. Moreover, the scapular-orientation group showed higher LT activation levels during arm elevation after training than the strengthening group (P = .03).

CONCLUSIONS

With or without biofeedback and cues, scapula-focused exercises improved scapular control and increased corticospinal excitability. Adding biofeedback and cues for scapular control during exercise helped facilitate greater LT activation, so feedback and cues are recommended during scapula-focused training.

Extracorporeal Shockwave Therapy for the Treatment of Noncalcific Rotator Cuff Tendinopathy: A Systematic Review and Meta-analysis

OBJECTIVE

The aim of the systematically review the short-, intermediate-, and long-term effects of extracorporeal shockwave therapy on pain intensity and shoulder function in individuals with noncalcific rotator cuff tendinopathy.

DESIGN

The MEDLINE, CINAHL, SPORTDiscus, and Embase were searched from inception up to June 2023. We included randomized controlled trials that investigated the effects of extracorporeal shockwave therapy on pain intensity and shoulder function.

RESULTS

Nine studies were included with a total sample of 543 individuals. Extracorporeal shockwave therapy was superior to sham extracorporeal shockwave therapy in improving pain intensity at short-term follow-up (standardized mean difference = -0.28; 95% confidence interval, -0.55 to -0.01). Extracorporeal shockwave therapy was not superior to sham extracorporeal shockwave therapy in improving pain intensity at intermediate- and long-term follow-ups ( P > 0.05). Extracorporeal shockwave therapy was not superior to other treatments in improving pain intensity at short- and intermediate-term follow-ups ( P > 0.05). Extracorporeal shockwave therapy was not superior to sham extracorporeal shockwave therapy and other treatments in improving shoulder function at short-, intermediate-, and long-term follow-ups ( P > 0.05).

CONCLUSIONS

Moderate-certainty evidence indicated that extracorporeal shockwave therapy showed small improvement in shoulder pain over sham extracorporeal shockwave therapy at short-term follow-up. In addition, extracorporeal shockwave therapy was not superior to sham extracorporeal shockwave therapy in improving function, and it was not superior to other treatments in improving shoulder pain and function.

Normal values of scapular muscle activity ratio during arm elevation and the relationship to muscle strength and sex difference

BACKGROUND

The normal value of the scapular muscle activity ratio during arm elevation is not clear.

OBJECTIVE

To obtain normal values of the scapular muscle activity ratio during arm elevation in healthy individuals.

METHODS

This cross-sectional study enrolled 47 healthy people. The participants performed shoulder flexion and lowered task with 90-degree movements every 2 seconds. Muscle activities of scapular muscles were measured. For normalization, the maximum isometric contraction of the shoulder flexion was measured at 90∘ (reference contraction). The integrated electromyographic value (IEMG) obtained during the task was normalized by IEMG during the reference contraction and the relative IEMG value was calculated. Then, the scapular muscle activity ratio was computed. The relationship between muscle strength and other factors was also investigated.

RESULTS

The median values for upper trapezius/serratus anterior and upper trapezius/lower trapezius were often approximately 1, and that for upper trapezius/middle trapezius was often between 1 and 2. The shoulder flexion isometric strength and scapular muscle activity ratio showed significant negative correlations in multiple phases.

CONCLUSION

Normal values for upper trapezius/serratus anterior and upper trapezius/lower trapezius during arm elevation and lowering were generally 1. Low muscle strength may contribute to an abnormal scapular muscle activity balance.

Comparing the effect of physiotherapy and physiotherapy plus corticosteroid injection on pain intensity, disability, quality of life, and treatment effectiveness in patients with Subacromial Pain Syndrome: a randomized controlled trial

PURPOSE

To compare the short and medium-term effects of physiotherapy plus corticosteroid injection (combined) with physiotherapy alone on pain intensity, disability, Quality of Life (QoL), and treatment effectiveness in patients with Subacromial Pain Syndrome (SAPS).

METHODS

In this double-blind, parallel Randomized Controlled Trial (RCT), 50 patients with SAPS were randomly assigned into combined (N = 25, a single injection 3-6 days before physiotherapy) and physiotherapy alone group (N = 25). Pain, disability, QoL, and treatment-effectiveness were measured at pre-intervention, post-intervention, and 3 and 6-month follow-up with Visual Analog Scale (VAS), Shortened Disability of the Arm, Shoulder, and Hand (Quick-DASH), Shoulder Pain and Disability Index (SPADI) (primary outcome measure), Western Ontario Rotator Cuff (WORC), and Global Rating of Change (GRC) respectively. A 2 × 4 (group × time) mixed model analysis of variance (ANOVA) was applied for analysis.

RESULTS

The ANOVA revealed statistically significant group-in-time interaction for all outcome measures (p-value < 0.05). The independent t-test showed more effectiveness in the combined group at medium-term, as the mean scores of almost all outcome measures were substantially lesser (p < 0.01). Moreover, in short-time, despite a greater number of patients stating "completely recovered" in the combined group, there was no statistically significant difference between groups.

CONCLUSIONS

Effects of physiotherapy plus corticosteroid injection could be more long-lasting than physiotherapy alone in improving pain intensity, disability, QoL, and treatment effectiveness in patients with SAPS.

TRIAL REGISTRATION NUMBER

IRCT20201010048980N1.IMPLICATIONS FOR REHABILITATIONShoulder pain is common, persistent, and predominantly results from subacromial pain syndrome (SAPS).Physiotherapy and corticosteroid injections are effective interventions for this condition.Comprehensive physiotherapy alone can be as effective as corticosteroid injection combined with physiotherapy in the short term.A combined approach versus physiotherapy alone may have more medium-term effects on SAPS patients' pain, disability, quality of life, and treatment effectiveness.

Dynamic evaluation of the sternoclavicular and acromioclavicular joints using an upright four-dimensional computed tomography

In the analysis of the shoulder complex, the sequential changes occurring in the sternoclavicular and acromioclavicular joints during active shoulder motion are challenging to track. This study aimed to investigate the in vivo sternoclavicular and acromioclavicular joint motions during active elevation, including the sequential changes in these joint spaces using upright four-dimensional computed tomography (4DCT). Bilateral shoulders of 12 healthy volunteers upright 4DCT were obtained during active elevation similar to a "hands up" motion. The sternoclavicular and acromioclavicular rotation angles, joint distances, and closest points on the clavicle relative to the thorax and scapula were evaluated during 10°-140° of humerothoracic elevation. During humerothoracic elevation, the clavicle elevated, retracted, and rotated posteriorly relative to the thorax, whereas the scapula rotated upwardly, internally, and posteriorly relative to the clavicle. All the sternoclavicular and acromioclavicular joint rotation angles were significantly different at ≥ 30°-50° of humerothoracic elevation compared with 10° of humerothoracic elevation. The mean sternoclavicular and acromioclavicular joint distances were 2.2 ± 1.1 mm and 1.6 ± 0.9 mm, respectively. The closest points were located on the anteroinferior part of the medial and lateral clavicle in the sternoclavicular and acromioclavicular joints, respectively. Significant differences were observed in the acromioclavicular joint distance and anterior/posterior movements of the closest points in the sternoclavicular and acromioclavicular joints compared with 10° of humerothoracic elevation. Our sternoclavicular and acromioclavicular closest point results indicate that the impingement tends to occur at the anteroinferior part of the medial and lateral aspects of the clavicle and may be related to osteoarthritis.

The effect of EMG biofeedback training on muscle activation in an impingement population

Subacromial impingement syndrome (SAIS) is one of the most diagnosed causes of pain in the upper extremity. The purpose of this study was to investigate muscle activity between asymptomatic and SAIS shoulders on the same subject while understanding the effectiveness of EMG biofeedback training (EBFB) on bilateral overhead movements. Ten participants (7 male), that tested positive for 2/3 SAIS clinical tests, volunteered for the study. Bilateral muscle activity was measured via electrodes on the upper trapezius (UT), lower trapezius (LT), serratus anterior (SA), and lumbar paraspinals (LP). Participants performed bilateral scapular plane overhead movements before and after EBFB. EBFB consisted of 10 bilateral repetitions of I, W, T, and Y exercises focused on reducing UT and increasing LT and SA activity. Prior to EBFB, no significant difference in muscle activity was present between sides. A significant main effect of time indicated that after EBFB both sides exhibited reduced UT activity at 60° (p = 0.003) and 90° (p = 0.036), LT activity was increased at all measured humeral angles (p < 0.0005), and SA muscle activity was increased at 110° (p = 0.001). EBFB in conjunction with scapular based exercise effectively alters muscle activity of asymptomatic and symptomatic scapular musculature.

Three-dimensional shoulder kinematics: Upright four-dimensional computed tomography in comparison with an optical three-dimensional motion capture system

Although shoulder kinematics have been analyzed by various methods, dynamic shoulder motion is difficult to track. This study aimed to validate the shoulder kinematic analysis using upright four-dimensional computed tomography (4DCT) and to compare the results with optical three-dimensional motion capture. During active elevation, bilateral shoulders of 10 healthy volunteers were tracked using 4DCT and motion capture. The scapulothoracic and glenohumeral rotations and the scapulohumeral rhythm (SHR) at each position were calculated, and the differences between 4DCT and motion capture were compared. During 10-140° of humerothoracic elevation, the scapulothoracic joint showed upward rotation, internal rotation, and posterior tilting, and the glenohumeral joint showed elevation, external rotation, and anterior plane of elevation in both analyses. In scapulothoracic rotations, the mean differences between the two analyses were -2.6° in upward rotation, 13.9° in internal rotation, and 6.4° in posterior tilting, and became significant with humerothoracic elevation ≥110° in upward rotation, ≥50° in internal rotation, and ≥100° in posterior tilting. In glenohumeral rotations, the mean differences were 3.7° in elevation, 9.1° in internal rotation, and -8.8° in anterior plane of elevation, and became significant with humerothoracic elevation ≥110° in elevation, ≥90° in internal rotation, and ≥100° in anterior plane of elevation. The mean overall SHRs were 1.8 in 4DCT and 2.4 in motion capture, and the differences became significant with humerothoracic elevation ≥100°. The 4DCT analysis of in vivo shoulder kinematics using upright computed tomography scanner is feasible, but the values were different from those by skin-based analysis at the elevated arm positions.

Subacromial Impingement Syndrome: A Systematic Review of Existing Treatment Modalities to Newer Proprioceptive-Based Strategies

Musculoskeletal pain is a common reason for primary care visits, with many visits for shoulder pain due to subacromial impingement syndrome (SIS). Current treatments lack evidence for effective management, showing only temporary outcomes. This systematic review evaluates existing modalities in comparison to the use of more permanent proprioceptive-based strategies. Specifically, this meta-analysis compared the use of kinesiology tape, myofascial trigger point release (MPTR), scapular stabilization exercises (SSE), and resistance training. PubMed, BioMedCentral, and ScienceDirect databases were queried for studies evaluating proprioceptive-based exercises in the last nine years. In total, 48 studies met the inclusion and exclusion criteria. After removing duplicates, a total of 14 level 1 studies were left. Kinesiology tape use demonstrated a statistically significant reduction in pain-free range of motion. MPTR improved in all pain scores and the disability scores index. SSE also reduced pain; however, mixed results were seen for range of motion. Finally, resistance training not only reduced pain but improved proprioception and joint position sense. Even though all techniques showed some promise in treating SIS, further large-scale studies exploring related outcomes are needed.

A randomized controlled trial of scapular exercises with electromyography biofeedback in oral cancer patients with accessory nerve dysfunction

PURPOSE

This study aims to investigate the effects of electromyography (EMG) biofeedback on scapular positions and muscle activities during scapular-focused exercises in oral cancer patients with accessory nerve dysfunction.

METHODS

Twenty-four participants were randomly allocated to the motor-control with biofeedback group (N = 12) or the motor-control group (N = 12) immediately after neck dissection. Each group performed scapular-focused exercises with conscious control of scapular orientation for 3 months. EMG biofeedback of upper trapezius (UT), middle trapezius (MT), and lower trapezius (LT) was provided in the motor-control with biofeedback group. Scapular symmetry measured by modified lateral scapular slide test; shoulder pain; active range of motion (AROM) of shoulder abduction; upper extremity function; maximal isometric muscle strength of UT, MT, and LT; and muscle activities during arm elevation/lowering in the scapular plane were evaluated at baseline and the end of the intervention.

RESULTS

After the 3-month intervention, only the motor-control with biofeedback group showed improving scapular symmetry. Although both groups did not show significant improvement in shoulder pain, increased AROM of shoulder abduction and muscle strength of the UT and MT were observed in both groups. In addition, only the motor-control with biofeedback group had improved LT muscle strength, upper extremity function, and reduced UT and MT muscle activations during arm elevation/lowering.

CONCLUSIONS

Early interventions for scapular control training significantly improved shoulder mobility and trapezius muscle strength. Furthermore, by adding EMG biofeedback to motor-control training, oral cancer patients demonstrated greater effectiveness in stabilizing scapular position, muscle efficiency, and upper extremity function than motor-control training alone.

TRIAL REGISTRATION

Institutional Review Board: This study was approved by the Chang Gung Medical Foundation Institutional Review Board (Approval No: 201901788A3. Approval Date: 2 January, 2020).

CLINICAL TRIAL REGISTRATION

This trial was registered at ClinicalTrials.gov (ClinicalTrials.gov ID: NCT04476004. Initial released Date: 16 July, 2020).

Postoperative Rehabilitation Protocol Following Arthroscopic Rotator Cuff Repair: A Prospective Single-Arm Pragmatic Interventional Study

Background and Objectives: Rotator cuff tear is the most common cause of shoulder pain. If nonsurgical treatment fails, arthroscopic rotator cuff repair (ARCR) is recommended. Since the standards for rehabilitation after ARCR are not clear, various rehabilitation methods have been suggested. This study intends to investigate the effect on the recovery phase of ARCR patients through a postoperative rehabilitation protocol (PRP) that considers the healing process and rehabilitation trend. Materials and Methods: This single-arm, pragmatic intervention study was conducted on 30 patients, two weeks postoperative day (POD) after ARCR. ARCR patients received intervention for six weeks from POD two-week, and pain intensity and shoulder function were evaluated at two-week intervals until POD 12-week, and range of motion (ROM) was evaluated at POD four-week and eight-week. Results: In this study, all variables improved over time (p < 0.05). As a result of the comparison between time points, a significant improvement was found in shoulder function at POD 6-week. In addition, the effect size had a large effect on ROM (flexion, scaption flexion, abduction, and external rotation) and shoulder function. Conclusions: Management through the PRP based on scientific evidence in the strategy of postoperative rehabilitation of patients with ARCR is effective for pain intensity, ROM, and shoulder function.

Comparing exercises with and without electromyographic biofeedback in subacromial pain syndrome: A randomized controlled trial

BACKGROUND

Deficits in movement and muscle activation of scapulohumeral joint are related to Subacromial Pain Syndrome. Electromyography biofeedback during exercise may enhance muscle activation and coordination, and consequently improve pain and shoulder function.

METHODS

This study compared the effects of an exercise protocol with and without using electromyographic biofeedback on pain, function and movement of the shoulder complex in subjects with Subacromial Pain Syndrome. A total of 24 patients with subacromial pain (mean age = 46.2 + 8.1;18 women) were randomized to either therapeutic exercise or exercise plus biofeedback to the trapezius and serratus muscles. Pain and shoulder function were evaluated as the primary outcome and range of motion, muscle strength, electromyographic activity and scapulohumeral kinematics as secondary outcomes. The subjects underwent eight weeks of intervention and comparisons were made between groups in baseline, at 4 weeks, 8 weeks, and at 4 weeks post intervention.

FINDINGS

There were differences between groups for pain [mean difference = 1.5 (CI 0.3, 3.2) p = 0.01] at 8 weeks in the Exercise group and scapular upward rotation at 60° of arm elevation [mean difference = 13.9 (CI 0.9, 9.3), p = 0.006] in the Biofeedback group. There was no difference for the other variables of scapular kinematics as well as for shoulder function (DASH), muscle strength, range of motion and electromyographic variables.

INTERPRETATION

The addition of Biofeedback to the exercise protocol increased upward rotation of the scapula. However, the volunteers who performed only the Exercises had a better response in reducing pain.

Online supervised versus workplace corrective exercises for upper crossed syndrome: a protocol for a randomized controlled trial

Background and objective

Musculoskeletal disorders (MSDs) including upper crossed syndrome (UCS) are considered as the leading cause of work-related issues worldwide among office workers. Therefore, the present study aims to evaluate the effect of workplace-based versus online-supervised home-based corrective exercises among office workers with UCS.

Methods and design

To this end, 45 subjects within the age range of 30–45 years are randomly assigned to three groups in the present parallel-group, randomized control trial using a pretest-posttest design. These groups include the subjects who receive online-supervised exercise and workplace exercise containing three sessions of intervention for 8 weeks and the control group receives no intervention while performing routine activities. The primary outcome variables are neck-shoulder pain (NSP) and consequent sick leave due to NSP, followed by alignment, workability, and the surface electromyography of upper, middle, and lower trapezius (UT, MT, and LT), sternocleidomastoid (SCM), and serratus anterior (SA) as the secondary variables.

Discussion

The present study seeks to assess the effect of workplace versus online-supervised corrective exercise interventions among 45 office workers suffering from UCS. It is expected to improve and reduce the related symptoms including postural malalignment and imbalance muscles after 8 weeks of corrective exercises. If effective, the findings may lead to adherence and work performance among the office workers, and individuals subjected to UCS can use the benefits of an online-supervised intervention. In addition, the findings may be useful in different workplaces as the evidence for employers to benefit from the reduction in the related costs and side effects of work-related neck/shoulder disorders including work disability, productivity loss, time expense, social insurance, work absenteeism, and treatment costs. Finally, clinicians and corrective exercise therapists can consider it as a clinical based-evidence intervention for their further actions.

Trial registration

Iranian Registry of Clinical Trials IRCT20200729048249N1. Registered on 5 October 2020 (https://en.irct.ir/user/trial/49992/view)

Effects of scapular stabilization exercises on posture and muscle imbalances in women with upper crossed syndrome: A randomized controlled trial

BACKGROUND

Scapular stabilization exercises can improve forward shoulder posture in young women. However, the effects of optimal exercise protocols on neck and shoulder postures, scapular muscle imbalance and thoracic kyphosis are still unclear.

OBJECTIVES

To investigate the effects of scapular stabilization exercises on neck and shoulder postures, scapular muscle imbalance and thoracic kyphosis in young women with upper crossed syndrome.

METHODS

Thirty-nine women aged 18-25 years with upper crossed syndrome were recruited. Participants were randomly allocated intotwo groups. The exercise group performed scapular stabilization exercises using elastic bands at 10 repetitions/set, 3 sets/day, and 3 days/week for 4 weeks. The control group did not perform any exercises during the experimental period. The cervical and shoulder angles were evaluated using the Kinovea program. A caliper, handheld dynamometer and flexi ruler were used to evaluate the length of the pectoralis minor, strength of the scapular stabilizer muscles and degree of the mid-thoracic curve, respectively.

RESULTS

The exercise group showed significant differences (p< 0.05) in the increase in cervical and shoulder angle, length of the pectoralis minor, and strength of the scapular muscles, except in the degree of mid-thoracic curve compared to the control group.

CONCLUSION

This study indicated that scapular stabilization exercises can improve forward head and shoulder posture, increase the flexibility of the pectoralis minor and strengthen the scapular muscles.

Scapular stabilization exercise based on the type of scapular dyskinesis versus traditional rehabilitation training in the treatment of periarthritis of the shoulder: study protocol for a randomized controlled trial

BACKGROUND

Periarthritis of the shoulder is a common disease leading to dysfunction of the shoulder joint and have a significant impact on patients' daily life. Evidence shows that there is a close relationship between scapular dyskinesis (SD) and shoulder diseases. Scapular stabilization exercise has been proved to be efficacious in relieving pain and improving function. However, there is no targeted exercise based on the type of scapular dyskinesis. This study will investigate the potential of scapular stabilization exercise based on the type of scapular dyskinesis in treating periarthritis of the shoulder.

METHODS

This study is a prospective, randomized controlled, parallel-group trial, intending to recruit 90 patients diagnosed with periarthritis of the shoulder. Patients will receive scapular stabilization exercise training based on the type of scapular dyskinesis or receive traditional rehabilitation training conducted for 30 min, once a day, for 6 weeks. The primary outcome is Constant-Murley score (CMS), and other outcomes include pain degree, range of motion (ROM), type of scapular dyskinesis, scapula position, and patients' satisfaction with shoulder function. Assessments will be performed at baseline, 2-, 4- and 6-week treatment, and at the 6-week follow-up after the end of treatment.

DISCUSSION

This study will be the first study to investigate the clinical efficacy of scapular stabilization exercise based on the type of scapular dyskinesis in patients with periarthritis of the shoulder. The results may provide evidence of the effect of targeted scapular stabilization exercise in improving shoulder function and correcting scapular dyskinesis, and provide valuable information for future research.

TRIAL REGISTRATION

This study had been registered in the Chinese Clinical Trials Registry. Registration number: ChiCTR2100044332 at March 14, 2021.

Does scapular corrective taping alter periscapular muscle activity and 3-dimensional scapular kinematics? A systematic review

STUDY DESIGN

This is a systematic review.

INTRODUCTION

Scapular taping is widely used in the management of scapular dysfunction. However, its effects on the scapular kinematics and the electromyography (EMG) activity of the periscapular muscles are not clear.

PURPOSE OF THE STUDY

The purpose of the study was to systematically review the current literature to examine whether scapular corrective taping alters the EMG activity of the periscapular muscles and the 3-dimensional scapular kinematics.

METHOD

MEDLINE and Web of Science databases were searched using specific mesh terms up to April 2018. A hand search was also conducted on the reference list of the included articles. A total of 157 studies were identified, and they were further analyzed for the eligibility to the systematic review. Studies that investigated the effects of scapular corrective taping on the EMG activity of the periscapular muscles and on the 3-dimensional scapular kinematics on patients with shoulder problems or asymptomatic subjects were eligible for the systematic review. The Cochrane Effective Practice and Organization of Care criteria were modified and used for the risk-of-bias assessment.

RESULTS

Eleven articles met the inclusion criteria and were included in the systematic review. Five studies investigated the effects of corrective taping on the scapular kinematics and 8 studies reported the effects of corrective taping on the EMG activity of the periscapular muscles. There was an agreement among the studies that scapular upward rotation is increased with the corrective taping, while there are inconsistent results concerning the scapular external rotation and posterior tilt. In addition, studies mostly reported that corrective taping decreases the activity of the upper trapezius, while it has conflicting effects on the activity patterns of other periscapular muscles.

DISCUSSION

Scapular corrective taping was found to increase the scapular upward rotation; however, its effects on scapular external rotation and posterior tilt are controversial. It was also found that corrective taping might decrease the EMG activity of the upper trapezius, while it had no effects on the activity of lower trapezius, and its effects on other periscapular muscles were controversial.

CONCLUSION

The results of the studies indicated that scapular corrective taping might alter the 3-dimensional scapular kinematics, while there are controversies about the effects of corrective taping on the EMG activity of the periscapular muscles. Further studies are needed to clarify the conflicts.

Effects of Conscious Control of Scapular Orientation in Oral Cancer Survivors With Scapular Dyskinesis: A Randomized Controlled Trial

OBJECTIVES

Spinal accessory nerve dysfunction is one of the complications of neck dissection in patients with oral cancer. This study aimed to explore the effects of long-term scapular-focused exercises and conscious control of scapular orientation on scapular movement and quality of life (QoL).

METHODS

This study was a randomized controlled trial with concealed allocation, assessor blinding, and intention-to-treat analysis. Thirty-six patients with oral cancer were randomly allocated to the motor-control group (scapular-focused exercise + conscious control of scapular orientation) or the regular-exercise group (scapular-focused exercises only). Both groups received conventional physical therapy after neck dissection for 3 months. Shoulder pain intensity, active range of motion (AROM) of shoulder abduction, scapular muscle strength and activity under maximal voluntary isometric contraction (MVIC), scapular muscle activity when performing scapular movements, and QoL were measured at baseline, 1 month after the start of the intervention, and the end of the intervention.

RESULTS

Both groups showed significant improvement in all outcomes except shoulder pain intensity. After the 3-month intervention, the motor-control group had more significant improvement in AROM of shoulder abduction with a 19° difference (95% CI: 10-29, P < .001), muscle strength of upper trapezius with an 11 N difference (95% CI: 2-20; P = .021), and QoL than the regular-exercise group. When performing shoulder horizontal adduction and flexion, the relative value (%MVIC) of serratus anterior was smaller in the motor-control group with a 106%MVIC difference (95% CI: 7-205, P = .037).

CONCLUSIONS

Scapular-focused exercises have promising effects on spinal accessory nerve dysfunction. Combining scapular-focused exercises with conscious control of scapular orientation has more remarkable benefits on AROM of shoulder abduction, UT muscle strength, and muscle activation pattern than the scapular-focused exercises alone. Conscious control of scapular orientation should be considered to integrate into scapular-focused exercises in patients with oral cancer and scapular dyskinesis.Trial registry name and URL, and registration number: ClinicalTrials.gov (URL: https://clinicaltrials.gov; Approval No: NCT03545100).

Scapular Dyskinesis Is Not an Isolated Risk Factor for Shoulder Injury in Athletes: A Systematic Review and Meta-analysis

BACKGROUND

Scapular dyskinesis has been considered a risk factor for athletic shoulder injury; however, findings in the prospective literature have demonstrated mixed results.

PURPOSE

To determine if scapular dyskinesis increases the risk of shoulder injury in athletes.

STUDY DESIGN

Meta-analysis.

METHODS

A systematic search was conducted on the MEDLINE, CINAHL Plus, SPORTDiscus, and Embase databases to identify prospective studies examining scapular dyskinesis and shoulder injury risk in athletes. Studies were included if they assessed participants using a dynamic scapular assessment at baseline and monitored for the development of shoulder injury. Data from the studies were subject to meta-analysis using the Mantel-Haenszel method to produce a pooled risk ratio.

RESULTS

Seven studies were eligible for inclusion, resulting in 212 shoulder injuries observed across 923 athletes. Scapular dyskinesis was present in 46% of participants, and these athletes had an injury rate of 25%. The presence of scapular dyskinesis displayed a trend to increase the risk of shoulder injury, but this was not statistically significant (risk ratio, 1.07; 95% CI, 0.85-1.34; P = .59).

CONCLUSION

Scapular dyskinesis was not significantly associated with the development of shoulder injury in athletes.

REGISTRATION

CRD42019133089 (PROSPERO).

Can the Use of Unstable Surfaces and Instruction for Conscious Abdominal Contraction Increase the EMG Activity of the Periscapular Muscles During the Dynamic Push-Up?

CONTEXT

It is believed that conscious abdominal contraction (CAC) during exercise encourages greater periscapular activation through existing myofascial connections. On the other hand, it is postulated that the use of unstable surfaces would promote greater neuromuscular demand.

OBJECTIVE

To analyze the effect of CAC on periscapular muscle activity during push-up plus exercise on stable and unstable surfaces and to evaluate the correlation between electromyographic (EMG) activity of the serratus anterior (SA) and abdominal oblique muscles.

DESIGN

Repeated-measures design in a single group, pre-post CAC.

SETTING

Biomechanics laboratory.

PARTICIPANTS

Twenty-three male volunteers without a history of lesions in the upper limbs participated in the study.

MAIN OUTCOME MEASURES

Five repetitions of push-ups on stable and unstable surfaces were performed with and without instruction for CAC. The normalized amplitude of the EMG activity was obtained from the muscles of the upper, middle, and lower trapezius, SA upper (SA_5th) and lower (SA_7th) portions, external oblique (EO), and internal oblique.

RESULTS

CAC increased the activity of the EO, internal oblique, middle trapezius, and SA (P < .05) in both surfaces. The use of the unstable surface increased the EMG activity of the EO, SA_7th, and middle trapezius and decreased the EMG activity of the SA_5th. However, all changes observed in EMG signals were of low magnitude, with effect sizes lower than 0.45. There was a weak correlation between the EMG activity of the EO and SA_5th (r = .24) and a strong correlation between the EO and SA_7th (r = .70).

CONCLUSION

The isolated use of CAC or unstable surface during push-up seems to present no practical relevance, but the combined use of these strategies may increase activation of the SA_7th and middle trapezius muscles.

Kinetic Chain Exercise Intervention Improved Spiking Consistency and Kinematics in Volleyball Players With Scapular Dyskinesis

Chang, C-C, Chang, C-M, and Shih, Y-F. Kinetic chain exercise intervention improved spiking consistency and kinematics in volleyball players with Scapular Dyskinesis. J Strength Cond Res XX(X): 000-000, 2020-Scapular dyskinesis (SD) is a common problem among volleyball players with chronic shoulder pain. This randomized controlled study examined the effectiveness of kinetic chain (KC) training on neuromuscular performance of the scapula and trunk during volleyball spikes. Forty volleyball players with SD and chronic shoulder pain received 4 weeks of KC training or the conventional shoulder exercise training (CT). Shoulder pain was assessed using the visual analogue scale (VAS) every week. The kinematics and muscle activation of the shoulder and upper trunk, and proprioceptive feedback magnitude (PFM) for scapular movement consistency, were recorded at the maximum shoulder flexion (T1) and ball contact (T2) during spiking tasks. The two-way repeated measures analysis of variances was used to assess the between-group differences before and after the intervention. The results showed a significant time by group interaction for the upper trunk rotation (p < 0.001) and PFM (p = 0.03) at T2. The post-hoc test indicated that the KC group significantly increased contralateral rotation of the upper trunk (9.63 ± 4.19° vs. -4.25 ± 10.05°), and improved movement consistency (error: 8.88 ± 11.52° vs. 19.73 ± 12.79°) at T2 compared with the CT group. Significant time effects were also identified for VAS, scapular upward rotation (T1 and T2), upper trunk contralateral side-bending and PFM at T1, and upper trunk contralateral rotation at T2. In conclusion, both KC and CT training would relieve shoulder pain and improve scapular and trunk movement, whereas the KC program was more effective for increasing scapular movement consistency and upper trunk rotation during volleyball spikes.

Estimating Muscle Forces for Breast Cancer Survivors During Functional Tasks

Breast cancer survivors have known scapular kinematic alterations that may be related to the development of secondary morbidities. A measure of muscle activation would help understand the mechanisms behind potential harmful kinematics. The purpose of this study was to define muscle force strategies in breast cancer survivors. Shoulder muscle forces during 6 functional tasks were predicted for 25 breast cancer survivors (divided by impingement pain) and 25 controls using a modified Shoulder Loading Analysis Module. Maximum forces for each muscle were calculated, and 1-way analysis of variance (P < .05) was used to identify group differences. The differences between maximum predicted forces and maximum electromyography were compared with repeated-measures analysis of variance (P < .05) to evaluate the success of the model predictions. Average differences between force predictions and electromyography ranged from 7.3% to 31.6% but were within the range of previously accepted differences. Impingement related pain in breast cancer survivors is associated with increased force of select shoulder muscles. Both pectoralis major heads, upper trapezius, and supraspinatus peak forces were higher in the pain group across all tasks. These force prediction differences are also associated with potentially harmful kinematic strategies, providing a direction for possible rehabilitation strategies.

Effects of adding scapular stabilization exercises to a periscapular strengthening exercise program in patients with subacromial pain syndrome: A randomized controlled trial

BACKGROUND

Interventions focused on the scapula should be considered in treating subacromial pain syndrome (SAPS). However, the effect of adding scapular stabilization exercises to protocols of progressive strengthening of the shoulder complex muscles on a non-multimodal approach remains unclear.

OBJECTIVE

To investigate the effect of adding scapular stabilization exercises, emphasizing retraction, and depression of the scapula, to a progressive periscapular strengthening protocol on disability, pain, muscle strength, and ROM in patients with SAPS.

DESIGN

Randomized, controlled, superiority trial, prospectively registered, two-arms, parallel, blind assessor, blind patient, and allocation concealment.

METHODS

Sixty patients with SAPS were randomly allocated into two groups: Periscapular Strengthening (PSG) or Scapular Stabilization (SSG) exercises. The interventions were performed three times a week for eight weeks. The primary outcome function and secondary outcomes (Pain, kinesiophobia, global perceived effect, satisfaction with treatment, the range of motion, scapula position and muscle strength) were measured in the baseline, four weeks, eight weeks (end of intervention) and 16 weeks after baseline. Shoulder pain and function were assessed by the Brazilian version of the Shoulder Pain and Disability Index (SPADI-Br).

RESULTS

A total of 60 patients were included and randomized to PSG (n = 30) or SSG (n = 30) from March 2016 to June 2017. There were no between group differences in primary and secondary outcomes at any time point.

CONCLUSION

The inclusion of the isolated scapular stabilization exercises, emphasizing retraction and depression of the scapula, to a progressive general periscapular strengthening protocol did not add benefits to self-reported shoulder pain and disability, muscle strength, and ROM in patients with SAPS.

TRIAL REGISTRATION

ClinicalTrials.gov.

Is there an association between changes in pain or function with changes in scapular dyskinesis: A prospective cohort study

OBJECTIVE

To assess the association between changes in pain or function with changes in scapular dyskinesis in participants with subacromial shoulder pain.

METHOD

Forty-four participants with subacromial shoulder pain were assessed at baseline and 8 weeks later. The outcome measures included 'pain at rest' and 'pain during movement' using Numeric Pain Rating Scale (NPRS), shoulder function using Patient Specific Functional Scale (PSFS), and observation of scapular movement pattern using the scapular dyskinesis test. Robust paired t-tests were used to compare scores between baseline and follow-up. Repeated measures correlation coefficient was used to assess the association between changes in pain or function with changes in scapular dyskinesis scores.

RESULTS

A fair association was found between improvement in function and improvement in scapular dyskinesis (correlation coefficient = -0.4, 95% CI: -0.6 to -0.1). No associations were found between changes in 'pain at rest' (correlation coefficient = -0.1, 95% CI: -0.2 to 0.2) or 'pain during movement' (correlation coefficient = 0.28, 95% CI: 0.0 to 0.5) with changes in scapular dyskinesis.

CONCLUSION

Our findings showed improvement in function is associated with improvement in scapular dyskinesis scores. Future studies should explore whether there is causal effect between improvement in scapular dyskinesis and function.

The Effect of Shoulder Mobilization on Scapular and Shoulder Muscle Activity During Resisted Shoulder Abduction: A Crossover Study of Asymptomatic Individuals

OBJECTIVE

The primary aim was to investigate the effect of inferior shoulder mobilization on scapular and shoulder muscle activity during resisted shoulder abduction in asymptomatic individuals.

METHODS

This was a lab-based, repeated-measures, crossover, randomized controlled study. Twenty-two participants were recruited. The order of experimental conditions was randomized. Each participant performed 5 repetitions of resisted shoulder abduction before and after the control and mobilization (grade +IV inferior shoulder mobilization, 3 sets, 60 seconds) conditions. Surface electromyography recorded the muscle activity of anterior, middle, and posterior deltoid; supraspinatus; infraspinatus; upper and lower trapezius; serratus anterior; and latissimus dorsi muscles.

RESULTS

Muscle activity levels reduced for infraspinatus (11.3% MVIC, 95% CI: 1.7-20.8), middle (22.4% MVIC, 95% CI: 15.9-28.8) and posterior deltoid (8.7 % MVIC, 95% CI: 4.6-12.9), and serratus anterior (-28.1% MVIC, 95% CI: 15.6-40.8) muscles after the mobilization condition during the eccentric phase of shoulder abduction. No carryover effects were observed, and within-session reliability was excellent (intraclass correlation coefficient scores ranging from 0.94 to 0.99).

CONCLUSION

Our findings suggest that inferior glenohumeral mobilization reduces activity levels of some scapular and shoulder muscles. Given the exploratory nature of our study, changes in muscle activity levels may have been found by chance. Confirmatory studies are required.

Effect of scapular stabilization exercise program in patients with subacromial impingement syndrome: a systematic review

Scapular stabilization approaches have been a mainstay of therapeutic training programs in the recent past for patients with subacromial im-pingement syndrome, whereas its contributions solely in the clinical outcome of reducing shoulder pain and disability are largely unclear. This systematic review aims to evaluate and summarize the best evi-dence regarding the role of scapular stabilization interventions in allevi-ating shoulder dysfunction among subjects with subacromial impinge-ment syndrome. Six reviewers involved in this systematic review. Liter-ature was retrieved systematically through searching 5 electronic data-bases (PubMed, MEDLINE, CINAHL, Cochrane, and Google Scholar). Articles published from the year 2010 up to and including 2019 were in-cluded. The literature search included clinical trials those intervened subjects with scapular exercises or scapular stabilization exercises or scapular rehabilitation, as an intervention for subacromial impingement syndrome. Seven studies, totaling 228 participants were included in this systematic review. Articles included in this review were graded ac-cording to Lloyd-Smith hierarchy of evidence scale and critically ap-praised with a tool developed by National, Heart, Lung and Blood Insti-tute (United States), named as quality assessment of controlled inter-vention studies tool. There was a significant effect on the scapular sta-bilization exercise program on improving pain and disability among sub-jects with subacromial impingement syndrome. This systematic review provides sufficient evidence to suggest that scapular stabilization exer-cises offers effectiveness in reducing pain and disability among sub-jects with subacromial impingement syndrome. However, more trials with larger sample are needed to provide a more definitive evidence on the clinical outcomes of scapular stabilization exercises among pa-tients with impingement.

Comparative study of the differences in shoulder muscle activation according to arm rotation angle

BACKGROUND

Scapular muscle exercise is important for patients with shoulder disorders. Distal variance leads to changes in shoulder muscle activation. Here, we aimed to determine whether scapular muscle activation is affected by different arm rotation angles.

METHODS

Overall, 30 healthy men participated in this study. The subjects were asked to keep their arms at 120 degrees of shoulder flexion while holding a 1.0-kg dumbbell in palms down (pronation) and palms up (supination) positions. Electromyography was used to measure anterior, middle, posterior deltoid, serratus anterior, upper, and lower trapezius muscle activation during the task. The muscle activations of each shoulder were compared between the pronation and supination positions.

RESULTS

Anterior deltoid and serratus anterior activations were significantly higher in supination than in pronation (p < .05). Alternatively, posterior deltoid and lower trapezius muscles were significantly more activated in pronation than in supination (p < .05).

CONCLUSION

Scapular muscle activation changed with arm rotation angle. Arm rotation angle should be assessed to estimate scapular muscle activation during exercise and motion analysis in clinical practice.

Muscle Contributions to Upper-Extremity Movement and Work From a Musculoskeletal Model of the Human Shoulder

Musculoskeletal models enable movement scientists to examine muscle function by computing the mechanical work done by muscles during motor tasks. To estimate muscle work accurately requires a model that is physiologically plausible. Previous models of the human shoulder have coupled scapula movement to humeral movement. While coupled movement produces a stereotypical scapulohumeral rhythm, it cannot model shrugging or independent movement of the scapula and humerus. The artificial coupling of humeral elevation to scapular rotation permits muscles that cross the glenohumeral joint, such as the rotator-cuff muscles and deltoids, to do implausible work to elevate and rotate the scapula. In reality, the motion of the scapula is controlled by thoracoscapular muscles, yet the roles of these muscles in shoulder function remains unclear. To elucidate the roles of the thoracoscapular muscles, we developed a shoulder model with an accurate scapulothoracic joint and includes scapular muscles to drive its motion. We used the model to compute the work done by the thoracoscapular muscles during shrugging and arm elevation. We found that the bulk of the work done in upper-extremity tasks is performed by the largest muscles of the shoulder: trapezius, deltoids, pectoralis major, and serratus-anterior. Trapezius and serratus anterior prove to be important synergists in performing upward-rotation of the scapula. We show that the large thoracoscapular muscles do more work than glenohumeral muscles during arm-elevation tasks. The model, experimental data and simulation results are freely available on SimTK.org to enable anyone to explore our results and to perform further studies in OpenSim 4.0.

Positive effects of neuromuscular shoulder exercises with or without EMG-biofeedback, on pain and function in participants with subacromial pain syndrome - A randomised controlled trial

BACKGROUND

The aim was to investigate the effect of Electromyography (EMG)-biofeedback guided exercises (BIONEX) on shoulder pain and function in participants with subacromial pain syndrome (SPS).

METHODS

Twenty-five women and 24 men (19-67 years), diagnosed with SPS, were randomised to BIONEX or the same exercises without EMG-biofeedback (NEX). Primary outcome was shoulder pain during the past 7 days (Numeric Pain Rating Scale (NPRS)). Secondary outcomes included self-reported (Disability of Arm Shoulder and Hand (DASH), Oxford Shoulder Score (OSS)), and measured shoulder function (surface EMG from upper trapezius, lower trapezius and serratus anterior) in mean and ratios of % of maximum voluntary EMG (%MVE) and onset time (msec), during arm tasks with 0, 1 and 3 kg.

RESULTS

There was no group difference (BIONEX versus NEX) in changed shoulder pain (NPRS, mean difference 0.18 (95% CI. -1.56; 1.19)), self-reported or measured shoulder function. Both groups, however, showed significant within-group improvements on self-reported outcomes (NPRS, DASH, OSS), only clinically relevant on NPRS (BIONEX 2.23 (SD 2.47); NEX 2.04 (SD 2.29)).

CONCLUSION

BIONEX and NEX were both effective in reducing pain to a clinically relevant level, while EMG-biofeedback did not make a difference. The current neuromuscular shoulder exercise protocol is recommended.

Quantifying acromiohumeral distance in elite male field hockey players compared to a non-athletic population

BACKGROUND

Shoulders of elite field hockey players are loaded continuously during play. Frequent high shoulder loading is known to influence certain shoulder variables, such as acromiohumeral distance. However, the influence of elite field hockey play on acromiohumeral distance is not examined yet.

OBJECTIVE

To examine the acromiohumeral distance in elite male field hockey players compared to a non-athletic control group.

DESIGN

Cross-sectional study.

METHODS

Fifty male participants were included; 25 elite field hockey players (age: 24.0±2.72 years; weight: 77.2±5.29kg; height; 180.5±5.37cm) and 25 age- and gender matched non-athletes (23.0±2.29 years; weight: 75.7±9.53kg; height: 181.8±5.52cm). A Telemed-Colormaster-128 EXT-IZ device was used to bilaterally obtain ultrasound acromiohumeral distance images at 3 different angles of shoulder abduction in the frontal plane.

RESULTS

Field hockey players showed a bilateral larger acromiohumeral distance at 45° (mean difference: 1.46mm [95% CI 0.46; 2.46]; p=0.005) and 60° (mean difference: 1.07mm [95% CI 0.21; 1.93]; p=0.016) compared to controls. In both groups, a significant but clinically less relevant, side difference was established for the acromiohumeral distance at 60° (mean difference: 0.79mm [95% CI 0.21; 1.34]; p=0.009).

CONCLUSION

With active shoulder abduction, elite field hockey players show a larger acromiohumeral distance in comparison to non-athletic participants. This may be a protective sport-specific adaptation, to better guard the shoulder from injury. Thus, acromiohumeral distance measurement may help physical therapists/coaches decide which athletes could benefit from specific, additional exercises aimed at enlarging the subacromial space.