From the Unstable Painful Shoulder to Multidirectional Instability in the Young Athlete

Does glenoid bone loss accompany posterior shoulder instability with only labral tear? A magnetic resonance imaging-based study

BACKGROUND

The primary aim of this study was to investigate bone loss in the glenoid with magnetic resonance imaging in posterior shoulder instability with only a labral tear.

METHODS

A total of 76 patients operated on because of posterior and anteroposterior shoulder instability only with a labral tear between 2006 and 2019 (n = 40 and n = 36, respectively) were included in this study. The instability type, a presence of an additional superior labrum anteroposterior (SLAP) lesion, the number of dislocations, and the magnetic resonance imaging-based measurements (the glenoid diameter and the bone defect size in the glenoid, the Hill-Sachs lesion [HSL] and the reverse HSL [rHSL] length, the angle and the arc length of HSL and rHSL, and the humerus head diameter and its area) were analyzed.

RESULTS

The size of the anterior glenoid defect, the rHSL measurements (length, angle, and arc length), and the ratio of the anterior glenoid defect size to the glenoid diameter were significantly higher for anteroposterior instability (P < .01) cases. There was no significant difference (P = .49, .64, and .82, respectively) for the presence of an additional SLAP pathology, the glenoid diameter, the posterior glenoid defect, and the ratio of the posterior glenoid defect size to the glenoid diameter in posterior and anteroposterior instability groups. The increased number of dislocations was associated with increased rHSL length and total arc length (P = .04 and .03, respectively). An additional SLAP lesion in posterior shoulder instabilities was not associated with the bone defect size (P = .29).

CONCLUSION

Although the posterior shoulder instability with only a labral tear is likely to cause a bone defect, we have shown that the instability is not expected to be caused by the bone defect. Therefore, this study points out that only soft tissue repair without considering the bone defect could be promising in this patient group.

Advances in the Non-Operative Management of Multidirectional Instability of the Glenohumeral Joint

Multidirectional instability (MDI) of the glenohumeral joint refers to symptomatic subluxations or dislocations in more than one direction. The aetiology of MDI is multifactorial, which makes the classification of this condition challenging. A shoulder rehabilitation program is the initial recommended treatment for MDI, however available rehabilitation programs have varying levels of evidence to support their effectiveness. In 2016, we published the details of an evidence-based program for MDI that has been evaluated for efficacy in two single-group studies and a randomised controlled trial. In 2017, we published a clinical commentary on the aetiology, classification, and treatment of this condition. The aim of this paper is to provide an update on the components of these publications with a particular focus on new advances in the non-operative management of this condition.

Pathology and surgical outcomes of unstable painful shoulders

Background

Boileau et al have reported on the unstable, painful shoulder (UPS), which was defined as painful shoulders without any recognized anteroinferior subluxations or dislocations that were associated with roll-over lesions (ie, instability lesions) on imaging or at arthroscopy. However, they included various pathologies, probably due to the ambiguity in their definitions of UPS. We redefined UPS as follows: (1) shoulder pain during daily or sports activities, (2) traumatic onset, (3) no complaint of shoulder instability, and (4) soft-tissue or bony lesions, such as Bankart or humeral avulsion of glenohumeral ligament lesion, confirmed by arthroscopy. The purpose of this study was to retrospectively investigate pathologies of UPS based on our definitions. We also aimed to assess the outcomes after arthroscopic soft-tissue stabilization for UPS.

Methods

We reviewed patients who were retrospectively diagnosed as UPS based on our definition and underwent arthroscopic stabilization between January 2007 and September 2018. Patients' demographics, physical and radiographic findings, intraoperative findings, clinical outcomes (Rowe scores, Subjective Shoulder Value [SSV], and the visual analog scale [VAS] for pain), and return to play sport (RTPS) were investigated.

Results

This study included 91 shoulders in 91 patients with a mean age of 23 years (range, 15-51). The mean follow-up was 37 months (range, 24-156). Eighty-seven patients were involved in sports activities: collision/contact, 55 patients (60%); overhead, 26 patients (29%). The pain was reproduced during the anterior apprehension test in 86 shoulders (95%). Normal type (49%) predominated in glenoid morphology followed by fragment (bony Bankart) type (37%). Most fragment-type lesions were seen in collision/contact athletes. Intraoperative findings demonstrated that Bankart lesions were found in all patients and Hill-Sachs lesions only in 42%. Magnetic resonance arthrography in the abducted and externally rotated positions showed a Bankart lesion in 76 shoulders (84%). Rowe score, SSV, and pain VAS significantly improved postoperatively (P < .001 for each). Forty-two of 70 athletes (60 %) with > 2-year follow-up returned to the sport at a complete or near-preinjury level. Six (9%) athletes experienced reinjury.

Conclusion

All shoulders that were diagnosed as UPS with our definition had a Bankart lesion. There seemed to be two different types of pathologies: Bankart lesions in lax shoulders and bony Bankart lesions in collision/contact athletes. The pain experienced during the anterior apprehension test may be useful for the diagnosis of UPS. Arthroscopic soft-tissue stabilization yielded good clinical outcomes with a high RTPS rate, but the reinjury rate was relatively high.

Muscle activity and scapular kinematics in individuals with multidirectional shoulder instability: A systematic review

BACKGROUND

Several studies reported the importance of glenohumeral and scapular muscle activity and scapular kinematics in multidirectional shoulder instability (MDI), yet a systematic overview is currently lacking.

OBJECTIVE

This systematic review evaluates and summarizes the evidence regarding muscle activity and shoulder kinematics in individuals with MDI compared to healthy controls.

METHOD

The electronic databases PubMed and Web of Science were searched in September 2020 with key words regarding MDI (population), muscle activity, and glenohumeral and scapular movement patterns (outcomes). All studies that compared muscle activity or scapular kinematics between shoulders with MDI and healthy shoulders were eligible for this review, except for case reports and case series. All articles were screened on the title and abstract, and remaining eligible articles were screened on full text. The risk of bias of included articles was assessed by a checklist for case-control data, as advised by the Cochrane collaboration.

RESULTS

After full text screening, 12 articles remained for inclusion and one study was obtained by hand search. According to the guidelines of the Dutch Institute for Healthcare Improvement, most studies were of moderate methodological quality. We found moderate evidence that MDI individuals show increased or prolonged activity of several rotator cuff muscles that control and centre the humeral head. Furthermore, we found evidence of decreased and/or shortened activity of muscles that move or accelerate the arm and shoulder girdle as well as increased and/or lengthened activity of muscles that decelerate the arm and shoulder girdle. The most consistent kinematic finding was that MDI individuals show significantly less upward rotation and more internal rotation of the scapula during elevation of the arm in the scapular plane as compared with controls. Finally, several studies also suggest that the humeral head demonstrates increased translations relative to the glenoid surface.

CONCLUSION

There is moderate evidence for altered muscle activity and altered humeral and scapular kinematics in MDI individuals as compared with controls.

Comprehensive review of the physical exam for glenohumeral instability

Glenohumeral instability is a common pathology of the shoulder joint, especially among young athletes. Despite advancements in technology and the widespread use of diagnostic imaging, a careful history and physical examination still remain the cornerstone of diagnosing patients with shoulder instability. Due to the involvement of many static and dynamic stabilizers, proficient physical examination can be challenging. With a systematic approach to clinical evaluation, the clinician can recognize characteristic patterns of relevant signs and symptoms and make an accurate diagnosis.

Assessing the Effectiveness of Evidence-Based Medicine in Practice: A Case Study of First-Time Anterior Shoulder Dislocations

BACKGROUND

The dissemination of evidence-based information into medical practice is essential to provide patients with optimal care and realize society's substantial investments in medical research. Effective information delivery and treatment utilization may lead to improvements in patient outcome, reductions in cost, and an overall lower burden on the health-care system. This study examines the dissemination of medical evidence following a first-time anterior shoulder dislocation (FTASD) and assesses the impact of potential dissemination strategies.

METHODS

The state of evidence dissemination into clinical practice for FTASD was evaluated with use of the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework. The treatment pathway for patients with FTASDs was mapped and evaluated using data that were collected through an orthopaedic shoulder-specialist survey and with review of a claims database.

RESULTS

A total of 1,755 patients with an FTASD were identified through a national claims database; 50% of patients followed up with a care provider within 30 days after an emergency department (ED) or urgent care visit. Based on shoulder-specialist survey data, physician estimates of the risk of redislocation within a 2-year window aligned with medical evidence 59% of the time. Only 29% of patients obtained information for FTASD that aligns with high-level medical evidence.

CONCLUSIONS

There are gaps and deficiencies in the dissemination and application of evidence in the treatment of FTASDs. Specifically, patients have limited exposure to health-care encounters where appropriate information related to low rates of follow-up following ED or urgent care visits may be communicated. Evaluating the current state of practice and identifying areas of improvement for the dissemination of evidence regarding FTASDs can be achieved through application of the RE-AIM framework. Greater consideration and resourcing of dissemination and implementation strategies may improve the dissemination and the impact of existing medical evidence.

The Posterior Unstable Shoulder: Natural History, Clinical Evaluation and Imaging

Background:

There is a low incidence of posterior instability which is present in only 2% to 10% of all unstable shoulders. The posterior instable shoulder includes different manifestations like fixed dislocation, recurrent subluxation or dislocation.

Methods:

Research and online content related to posterior instability is reviewed. Natural history, clinical evaluation and imaging are described.

Results:

An awareness of the disorder, together with a thoughtful evaluation, beginning with the clinical history, usually leads to proper diagnosis. An appropriate physical exam, taking in account hyperlaxity and specific tests for posterior instability should be done.

Conclusion:

Posterior shoulder instability is an uncommon condition and is challenging to diagnose. There is not a single injury that is responsible for all cases of recurrent shoulder dislocation or subluxation, and the presence of soft tissue lesions or bone alterations should be evaluated, with the use of adequate simple radiology and multiplanar imaging.

Physical Exam and Evaluation of the Unstable Shoulder

Background:

The clinical evaluation of the patient with shoulder instability can be challenging. The pathological spectrum ranges from the straightforward “recurrent anterior dislocation” patient to the overhead athlete with a painful shoulder but not clear instability episodes. Advances in shoulder arthroscopy and imaging have helped in understanding the anatomy and physiopathology of the symptoms. The aim of this general article is to summarize the main examination manoeuvres that could be included in an overall approach to a patient with a suspicion of instability.

Material and Methods:

In order to achieve the above-mentioned objective, a thorough review of the literature has been performed. Data regarding sensibility and specificity of each test have been included as well as a detailed description of the indications to perform them. Also, the most frequent and recent variations of these diagnostic tests are included.

Results:

Laxity and instability should be considered separately. For anterior instability, a combination of apprehension, relocation and release tests provide great specificity. On the other hand, multidirectional or posterior instability can be difficult to diagnose especially when the main complain is pain.

Conclusion:

A detailed interview and clinical examination of the patient are mandatory in order to identify a shoulder instability problem. Range of motion of both shoulders, clicking of catching sensations as well as pain, should be considered together with dislocation and subluxation episodes. Specific instability and hyperlaxity tests should be also performed to obtain an accurate diagnosis.

Evidence-based rehabilitation of athletes with glenohumeral instability

PURPOSE

To give an overview of current knowledge and guidelines with respect to evidence-based rehabilitation of athletes with glenohumeral instability.

METHODS

This narrative review combines scientific evidence with clinical guidelines based on the current literature to highlight the different components of the rehabilitation of glenohumeral instability.

RESULTS

Depending on the specific characteristics of the instability pattern, the severity, recurrence, and direction, the therapeutic approach may be adapted to the needs and demands of the athlete. In general, attention should go to (1) restoration of rotator cuff strength and inter-muscular balance, focusing on the eccentric capacity of the external rotators, (2) normalization of rotational range of motion with special attention to the internal rotation ROM, (3) optimization of the flexibility and muscle performance of the scapular muscles, and (4) gradually increasing the functional sport-specific load on the shoulder girdle. The functional kinetic chain should be implemented throughout all stages of the rehabilitation program. Return to play should be based on subjective assessment as well as objective measurements of ROM, strength, and function.

CONCLUSIONS

This paper summarizes evidence-based guidelines for treatment of glenohumeral instability. These guidelines may assist the clinician in the prevention and rehabilitation of the overhead athlete.

LEVEL OF EVIDENCE

Expert opinion, Level V.

Posteroinferior shoulder instability: clinical outcome of arthroscopic stabilization in 32 shoulders and categorization based on labral mapping

INTRODUCTION

Posterior shoulder instability is rare, appears in varying clinical patterns and can be the main symptom in patients with instability in more than one direction. The purpose was to analyze and categorize our patients and to report on the results of operative treatment by arthroscopy.

MATERIALS AND METHODS

A consecutive series of 32 shoulders in 31 patients from a 7-year period was chosen for retrospective clinical evaluation with VAS for pain, Rowe Score, Constant Score and Simple Shoulder Test. Follow-up rate was 100 %, the mean FU period was 28 months (range 13-58). Allocation based on clinical and intraoperative criteria resulted in the 4 groups A to D characterized by an increasing traumatic impact. Patients received a posterior Bankart repair with bone anchors in 21 or capsular plication to the intact labrum in 11 cases.

RESULTS

The clinical outcome scores were generally good and all showed a trend towards better results from A to D, but without significance. Pain on VAS pre- and postoperatively showed a significant (p < 0.0001) overall decline from 7.4 to 1.8. The Rowe Score increased significantly (p < 0.0001) from a mean value of 41.4 to 89.5 points. Three patients were reoperated and satisfied, four patients (12.5 %) not satisfied at follow-up. The drive-through sign was significantly (p = 0.003) more distinct in the less traumatic groups A and B than groups C and D. Subgroup allocation resulted in the following distribution: 7 patients qualified for group A (PPM = predominantly posterior multidirectional), 13 for B (RPS = recurrent posterior subluxation), 7 for C (unidirectional) and 5 patients for group D (bi-directional). Graphic display of labral lesions, called "labral mapping", revealed typical patterns for the groups.

CONCLUSION

In patients with posteroinferior shoulder instability, good results can be obtained with the arthroscopic treatment of all identified pathologies. Categorization into one of four subgroups might be a valuable tool regarding the choice of the operative treatment options.