Laxity testing of the shoulder: a review

Development of a novel animal model of rotator cuff tear arthropathy replicating clinical features of progressive osteoarthritis with subchondral bone collapse

OBJECTIVE

To establish an animal model of modified cuff tear arthropathy (mCTA) in order to better replicate the pathophysiology associated with rotator cuff tear-induced humeral head collapse.

DESIGN

mCTA was induced by transection of the rotator cuff, the long head of the biceps brachii (LHB), and superior half of the joint capsule in the right shoulder of 12-week-old rats; the left shoulder underwent sham surgery. The severity of CTA was quantitated using the Murine Shoulder Arthritis Score (MSAS). The trabecular bone of the humeral head and metaphysis was analyzed using bone histomorphometry. The expression of proinflammatory cytokines and catabolic enzymes was evaluated immunohistochemically.

RESULTS

In the mCTA model, the MSAS increased starting from 2 weeks after induction, and there was notable subchondral bone collapse with fibrous cells at 4 weeks. The mCTA cartilage exhibited positive staining for TNF-α, IL-1β/6, MMP-3/13, and ADAMTS5. The trabecular bone volume was reduced not only in the subchondral bone but also in the metaphysis of the humeri, and bone resorption was enhanced in these areas. In the collapsed subchondral bone, both bone formation and resorption were increased. The fibrous cells showed expression of TNF-α, IL-6, and MMP-13, along with specific markers of mesenchymal stem cells. Furthermore, the fibrous cells showed osteoblastic characteristics (RUNX2-positive) and expressed RANKL.

CONCLUSIONS

The LHB and the capsuloligamentous complex are critical stabilizers of the glenohumeral joint, serving to prevent the advancement of CTA following massive rotator cuff tears. Fibrous cells appear to play a role in the humeral head bone resorption.

Inconsistency in Shoulder Arthrometers for Measuring Glenohumeral Joint Laxity: A Systematic Review

There is no consensus on how to measure shoulder joint laxity and results reported in the literature are not well systematized for the available shoulder arthrometer devices. This systematic review aims to summarize the results of currently available shoulder arthrometers for measuring glenohumeral laxity in individuals with healthy or injured shoulders. Searches were conducted on the PubMed, EMBASE, and Web of Science databases to identify studies that measure glenohumeral laxity with arthrometer-assisted assessment. The mean and standard deviations of the laxity measurement from each study were compared based on the type of population and arthrometer used. Data were organized according to the testing characteristics. A total of 23 studies were included and comprised 1162 shoulders. Populations were divided into 401 healthy individuals, 278 athletes with asymptomatic shoulder, and 134 individuals with symptomatic shoulder. Sensors were the most used method for measuring glenohumeral laxity and stiffness. Most arthrometers applied an external force to the humeral head or superior humerus by a manual-assisted mechanism. Glenohumeral laxity and stiffness were mostly assessed in the sagittal plane. There is substantial heterogeneity in glenohumeral laxity values that is mostly related to the arthrometer used and the testing conditions. This variability can lead to inconsistent results and influence the diagnosis and treatment decision-making.

Posterior Shoulder Instability in Tennis Players: Aetiology, Classification, Assessment and Management

Background

Micro-traumatic posterior shoulder instability (PSI) is an often missed and misdiagnosed pathology presenting in tennis players. The aetiology of micro-traumatic PSI in tennis players is multifactorial, including congenital factors, loss of strength and motor control, and sport-specific repetitive microtrauma. Repetitive forces placed on the dominant shoulder, particularly combinations of flexion, horizontal adduction, and internal rotation contribute to the microtrauma. These positions are characteristic for kick serves, backhand volleys, and the follow-through phase of forehands and serves. The aim of this clinical commentary is to present an overview of the aetiology, classification, clinical presentation, and treatment of micro-traumatic PSI, with a particular focus on tennis players.

Level of Evidence

5.

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.

Kinesio taping with ballistic six plyometric training on speed, accuracy, target and joint proprioception in fast bowlers with glenohumeral instability

Cricket is one of the most popular international sports played worldwide. Ballistic six plyometric training improves throwing activity in throwing sports, improves rotator cuff muscular strength, and prevents and reduces the risk of shoulder injury associated with overhead pitching. Kinesiotaping is used in rehabilitation, as a treatment for sportsrelated injuries, and as a means of injury prevention. The objective of the study was to compare the combined effect of kinesiotaping with ‘ballistic six plyometric training’ and with ballistic six plyometric training alone on speed, accuracy, target and joint proprioception in fast bowlers with mild glenohumeral joint instability. Thirty male semiprofessional fast bowlers in the age group of 20-30 years were included in this study and randomly divided into two groups: group A and group B with 15 players in each group. Group A received kinesiotaping along with ballistic six plyometric training, whereas group B was only given ballistic six plyometric training. Both groups also performed conventional upper extremity workouts. All players were evaluated for bowling speed, accuracy, target and joint proprioception (internal rotation & external rotation) with a radar gun, cricket specific bowling accuracy test, no. of balls hit stump in an over and inclinometer, respectively. Both groups improved significantly at the end of week 8, however, group B showed significant difference for bowling speed, accuracy, target and joint proprioception (P<0.05). Rehabilitation protocol comprising of combined kinesiotaping, plyometrics along with conventional protocol can be beneficial in enhancing performance related variables, i.e. bowling speed, accuracy and target in fast bowlers with mild glenohumeral instability.

Rehabilitation for atraumatic shoulder instability in circus arts performers: delivery via telehealth

BACKGROUND

The Watson Instability Program (WIP1) is current best evidence for conservative management of atraumatic shoulder instability, but it is unknown if this program can be effectively delivered via tele-consultation. The purpose of this longitudinal pre-post intervention study was to determine the effects of the WIP1 on patient-reported outcome measures, scapular position, shoulder strength, and handstand stability in student circus performers with atraumatic shoulder instability when delivered via tele-consultation.

METHODS

Student circus performers aged between 15 and 35 years from the National Institute of Circus Arts were recruited. A 12-week shoulder exercise program was delivered via tele-consultation during the Melbourne, Australia COVID-19 (coronavirus disease 2019) lockdown. The primary outcome measures were the Western Ontario Shoulder Instability Index score and the Melbourne Instability Shoulder Scale score. Secondary outcomes measures included the Orebro Musculoskeletal Pain Questionnaire, the Tampa Scale for Kinesiophobia, and physical assessment measures including strength via handheld dynamometry, scapular position using an inclinometer, and handstand stability via center-of-pressure fluctuation. Patient-reported outcomes were collected at baseline and 6-week, 12-week, 6-month, and 9-month time points, and physical outcomes were measured at baseline and 9-month time points. A repeated-measures mixed model (with effect sizes [ESs] and 95% confidence intervals [CIs]) was used to analyze patient-reported outcomes, handstand data, strength, and scapular measures. Significance was set at P < .05.

RESULTS

Twenty-three student circus arts performers completed the study. Significant improvements were found in both Western Ontario Shoulder Instability Index scores (effect size [ES], 0.79 [95% CI, 0.31-1.33] at 6 weeks; ES, 1.08 [95% CI, 0.55-1.6] at 12 weeks; ES, 1.17 [95% CI, 0.62-1.78] at 6 months; and ES, 1.31 [95% CI, 0.74-1.95] at 9 months; P < .001) and Melbourne Instability Shoulder Scale scores (ES, 0.70 [95% CI, 0.22-1.22] at 6 weeks; ES, 0.83 [95% CI, 0.34-1.37] at 3 months; ES, 0.98 [95% CI, 0.46-1.54] at 6 months; and ES, 0.98 [95% CI, 0.43-1.50] at 9 months; P < .001), as well as Orebro Musculoskeletal Pain Questionnaire scores at all follow-up time points. The Tampa Scale for Kinesiophobia scores reached significance at 6 weeks and 12 weeks. Following rehabilitation, we found statistically significant increases in shoulder strength in all positions tested and increased scapular upward rotation measured at end-of-range abduction, as well as during loaded external rotation. The affected arm showed greater instability than the unaffected arm with a significant intervention effect on the affected arm showing a greater consistent anterior-posterior movement pattern.

CONCLUSION

In a group of circus performers with atraumatic shoulder instability, treatment with the WIP1 via telehealth resulted in clinically and statistically significant improvements in shoulder symptoms and function.

An improved quantitative ultrasonographic technique could assess anterior translation of the glenohumeral joint accurately and reliably

PURPOSE

Since poor repeatability of the load and shift test using a grading scale has been reported, an objective and quantitative method to assess anterior translation should be established to assess glenohumeral joint function. The purpose of this study was to assess the accuracy and repeatability of the ultrasonographic techniques to quantify anterior translation of the glenohumeral joint.

METHODS

Eight fresh-frozen cadaveric shoulders were used. For the standard technique, the ultrasound transducer was positioned on the anterolateral aspect of the shoulder viewing the coracoid process, glenoid, and humeral head. For the revised technique, the transducer was positioned on the anterior aspect of the shoulder, perpendicular to the scapular plane, viewing the conjoint tendon, glenoid, and humeral head. During the load and shift test, the distance between anterior edges of the glenoid and the humeral head was measured. The difference between distances before and after applying an anterior load was calculated as an anterior translation and compared with the anterior translation assessed using a motion tracking system. The repeatability and accuracy of both techniques were analyzed statistically.

RESULTS

Intra- and inter-observer repeatability was good-excellent for both ultrasonographic techniques (ICC, 0.889-0.998). The revised technique achieved a stronger correlation to the anterior translations obtained using the motion tracking system (R = 0.810-0.913, p < 0.001) than the standard technique (R = 0.619-0.806, p < 0.001).

CONCLUSION

Better accuracy and repeatability was found in the revised technique than the standard technique. The revised technique will be useful to determine the individual laxity and modify the treatment plan and return-to-sports protocol.

LEVEL OF EVIDENCE

III.

Posterior shoulder instability: a systematic review

INTRODUCTION

This review aims to provide information on outcomes of surgical procedures for soft tissue or bony glenoid and/or humeral abnormalities in case of posterior shoulder instability.

SOURCE OF DATA

A systematic review of the literature according to the PRISMA guidelines was performed. A comprehensive search of PubMed, Medline, CINAHL, Cochrane, Embase, Ovid and Google Scholar databases using various combinations of the keywords 'shoulder', 'posterior instability', 'dislocation', 'reversed bony bankart', 'reversed Hill Sachs', and 'capsulolabral' was performed.

AREAS OF AGREEMENT

A total of 847 shoulders in 810 patients were included. A redislocation event occurred in 33 (8.7%) of 411 shoulders with soft tissue abnormalities and in 12 (9.1%) of 132 shoulders with bony abnormalities of the glenoid, humeral head or both.

AREAS OF CONTROVERSY

The optimal treatment modalities for posterior shoulder dislocation remain to be defined.

GROWING POINTS

Operative stabilization for posterior shoulder instability should be lesion-specific and should correct all components of the posterior instability.

AREAS TIMELY FOR DEVELOPING RESEARCH

Future prospective studies should aim to establish the optimal treatment modalities for posterior shoulder instability.

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.

Comparison of some intrinsic risk factors of shoulder injury in three phases of menstrual cycle in collegiate female athletes

OBJECTIVES

present study aims to investigate the changes in the shoulder joint stability factors during the menstrual cycle.

DESIGN

cross-sectional study; SETTING: laboratory.

PARTICIPANTS

15 healthy collegiate female athletes with normal menstrual cycles.

MAIN OUTCOME MEASURES

shoulder strength, proprioception, laxity and functional stability were the primary outcomes. Participants were assessed in three phases (mense, ovulation, midluteal (day 21) by 4 different categories of tests, each designed for a different factor. Shapiro-Wilk Test was used to determine normality of data, ANOVA and Friedman Test were used to compare results. Significance level and alpha were considered 95 percent and ≥0.05, respectively. Data shown a relation between proprioception, strength and menstrual cycle.

RESULTS

shoulder strength was significantly increased in ovulation phase compared to other phases (p < 0.5) (effect size >0.14). Proprioception was significantly decreased in luteal phase than in mense and ovulation phases (p < 0.5) (effect size >0.14). Finally, ligament laxity and functional stability showed no change in all phases (p < 0.5).

CONCLUSION

Menstrual cycle and sexual hormones affect muscle strength and proprioception of shoulder joint, but have no effect on ligament laxity and functional stability.

Radiographic evaluation of the glenohumeral joint space in patients undergoing arthroscopic shoulder surgery in the beach-chair position

Background

Shoulder arthroscopy can be performed with the patient in the lateral decubitus or beach-chair position, but in both cases, glenohumeral (GH) joint spaces must be increased to improve visualization and allow access of the optical instrument. The aim of this study was to determine the effects of limb setup and longitudinal traction on the opening of the GH space with patients placed in the beach-chair (dorsal decubitus) position.

Methods

GH spaces at 3 test points corresponding to the anatomic locations of Bankart lesions were determined indirectly from radiographic images obtained from 67 patients presenting shoulder pathology with an indication for arthroscopic surgery. Measurements were made with the operative limb in neutral rotation and positioned in relation to the coronal plane in adduction, 45° of abduction, or adduction with an axillary spacer, in each case with and without longitudinal traction.

Results

GH spaces were optimized at 2 of 3 test points when the operative limb was positioned in adduction or neutral rotation and manual longitudinal traction was applied with or without a polystyrene spacer placed under the axilla, but use of the spacer was essential to maximize the GH space at all 3 locations. In contrast, 45° of abduction proved to be the least appropriate position because it afforded the smallest GH space values with or without traction.

Conclusion

Appropriate positioning of the patient on the operating table is a critical aspect of shoulder arthroscopy. Radiographic images revealed that adducted upper-limb traction with the use of an axillary spacer in patients in the beach-chair position generates a significant increase in the GH space in the lower half of the glenoid cavity, thereby facilitating visualization and access of the optical equipment to the GH compartments.

Biomechanics of posterior shoulder instability - current knowledge and literature review

Posterior instability of the shoulder is a rare condition and represents about 10% of shoulder instability. It has become more frequently recognized in the last year, even though it is more difficult to diagnose than anterior shoulder instability. As this form of shoulder pathology is somewhat rare, biomechanical knowledge is limited. The purpose of our study was to perform an extensive literature search, including PubMed and Medline, and to give an overview of the current knowledge on the biomechanics of posterior shoulder instability. The PubMed/Medline databases were utilized, and all articles related to posterior shoulder instability and biomechanics were included to form a comprehensive compilation of current knowledge. A total of 93 articles were deemed relevant according to our inclusion and exclusion criteria. As expected with any newly acknowledged pathology, biomechanical studies on posterior shoulder instability remain limited in the literature. Current biomechanical models are performed in a static manner, which limits their translation for explaining a dynamic pathology. Newer models should incorporate dynamic stabilization of both the rotator cuff and scapulothoracic joint. There is a current lack of knowledge with regards to the pathomechanism of posterior shoulder instability, with no consensus on appropriate treatment regimens. Further investigation is therefore required at both basic science and clinical levels.

Alterations in scapulothoracic and humerothoracic kinematics during the tennis serve in adolescent players with a history of shoulder problems

The tennis serve generates high musculoskeletal loads at the shoulder complex, making athletes particularly vulnerable to chronic injuries, especially adolescent players. Chronic injuries are commonly related to altered scapular kinematics. This study explored the effects of a history of shoulder problems involving humerothoracic and scapulothoracic kinematics during the tennis serve at low speed in adolescent competitive players with and without a history of dominant shoulder problems. Totally, 28 adolescent tennis players were split into two groups, those with and those without a history of shoulder problems. Data on humeral and scapular kinematics relative to the thorax were collected using an electromagnetic system during slow velocity serves. The two groups's humerothoracic and scapulothoracic 3D joint angles were compared both at the end of the cocking phase and at the end of the acceleration phase of the tennis serve. At the end of the cocking phase, the players with a 30 history of shoulder problems showed less humeral abduction and external rotation and more scapular upward rotation. This group also showed less humeral abduction at the end of the acceleration phase. Players with a history of shoulder problems adapted their humerothoracic and scapulothoracic orientations to preserve shoulder integrity during the tennis serve.

Traumatic Instability: Treatment Options and Considerations for Recurrent Posttraumatic Instability

Recurrent traumatic glenohumeral instability is a complex problem with multiple variables to consider, but patient demographics, activities, as well as clinical and radiographic findings provide significant information to help choose the best treatment option. Although nonoperative treatment is a viable option for primary glenohumeral instability and in-season instability, recurrent instability exhibits anatomic factors which render nonsurgical treatment limited in scope. A proper patient history, clinical examination, and standard and advanced imaging are necessary in the assessment of patients with recurrent traumatic instability. Age, activity, hypermobility, tissue quality, glenoid and humeral head bone stock, and any prior surgical treatment are factors that must be considered for surgical planning. Open and arthroscopic Bankart repairs are good surgical options when bone loss is not an issue but increasing glenoid or humeral osseous deficiency in this setting frequently warrants additional procedures which address bony insufficiency. Controversy remains concerning the threshold value for glenoid bony deficiency and combined, bipolar defects, but this critical number may be less than previously suspected. Despite this controversy, successful surgical treatment of recurrent glenohumeral instability is possible when properly assessed and the correct surgery applied.

Arthroscopic knotless anterior labral stabilization using labral tape and wide awake anaesthesia-short term results

BACKGROUND

The shoulder is the least constrained of all joints of the body and is more susceptible to injury including dislocation. The rate of recurrent instability following primary stabilization procedure at 10 years of follow-up ranged from 3.4 to 20%. There is a lack of evidence in the literature regarding use of labral tape and anchors for anterior stabilization despite the growing market for this product. We describe the outcomes of 67 patients who underwent knotless arthroscopic anterior stabilisation under awake anaesthesia using 1.5 mm LabralTape with 2.9 mm Pushlock anchors for primary anterior instability by a single surgeon.

METHODS

This was a retrospective analysis of prospectively collected outcome data for adult patients undergoing anterior stabilisation for primary traumatic anterior shoulder instability between 2013 and 2016 at two centres. Patients with > 25% glenoid bone loss, engaging Hill Sach's, and multidirectional instability were excluded. All cases underwent surgery using awake anaesthetic technique. The surgical technique and post-operative physiotherapy was standardized. Outcomes were measured at 6 months and 12 months.

RESULTS

Of the 74 patients in our study, 7 were lost to follow up. Outcomes were measured using the Oxford Instability Shoulder Score (OISS) and clinical assessment including the range of motion. The OISS showed statistically significant improvement from a mean score and standard deviation (SD) of 24.72 ± 2.8 pre-surgery to 43.09 ± 3.5 after the procedure at 12 months with good to excellent outcomes in 66 cases (98.5%). The mean abduction was 134.2 ± 6.32 and external rotation was 72.55 ± 5.42 at 60-90 position at 12 months. We report no failures due to knot slippage or anchor pull-out.

CONCLUSION

Our case series using the above technique has distinct advantages of combining a small non-absorbable implant with flat, braided, and high-strength polyethylene tape. This technique demonstrates superior medium term results to conventional suture knot techniques for labral stabilization thereby validating its use.

Does the Beighton Score Correlate With Specific Measures of Shoulder Joint Laxity?

Background

Evaluation of shoulder joint laxity is an important component of the shoulder examination, especially in the setting of shoulder instability. Measures of generalized joint laxity, particularly the Beighton score, are often recorded and used to help make management decisions in these cases. However, no evidence is available to show that the Beighton score corresponds to specific measures of shoulder joint laxity.

Purpose

To assess the correlation between the Beighton score and validated measures of shoulder joint laxity.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

A total of 160 participants (age range, 16-35 years) with no history of shoulder joint abnormality were examined. The Beighton score, glenohumeral external rotation (standing and lying), glenohumeral abduction, and the sulcus sign were recorded. The relationship between the Beighton score and each measure of shoulder joint laxity was assessed.

Results

A high proportion of participants (34%) had a Beighton score of 4 or higher. Rates of positive shoulder laxity tests were lower (11%-19%). A positive Beighton score was a poor predictor of abnormal shoulder laxity, with low sensitivity (range, 0.40-0.48) and low positive predictive values (range, 0.13-0.31). Spearman correlation coefficients demonstrated poor correlation between the Beighton score and all measures of shoulder joint laxity when assessed as continuous variables (range, 0.29-0.45).

Conclusion

The Beighton score has poor correlation with specific measures of shoulder joint laxity and should not be considered equivalent to these tests as a method of clinical assessment.

Multidirectional instability of the glenohumeral joint: Etiology, classification, assessment, and management

Multidirectional instability of the shoulder is a type of glenohumeral joint shoulder instability. There are discrepancies in the definition and classification of this condition, which can make diagnosis and treatment selection challenging. Knowledge of contributing factors, the typical clinical presentation, and current best evidence for treatment options can assist in the diagnosis and appropriate treatment selection for this pathology. The purpose of this article is to present an overview of the current literature regarding the etiology, classification, assessment, and management of multidirectional instability of the glenohumeral joint.

Muscle regeneration through therapy with estromal stem cells in injury of infraespinhosus muscle of sheep

PURPOSE

To evaluate the effects of rotator cuff muscle regeneration in sheep and establish an experimental model for the use of autologous stem cells as a treatment option for tendon injuries.

METHODS

Infrared muscle tenotomies and Penrose drain implantation were performed on 12 shoulders of six clinically healthy adult sheep. After 60 days, the tendons were submitted to tissue repair, drainage removal, and divided into two groups according to the use of autologous stromal stem cells for treatment. Muscle regeneration was performed by biopsy on days 14 and 34 after repair.

RESULTS

The treatment group with cell therapy showed neovascularization and expressive regeneration. Complete regeneration of the muscle pattern did not occur in any sample although some muscle gain was obtained in the group 1 samples at 34 days after repair and introduction of stem cells. Fatty infiltration of these samples from group 1 at 34 days was less intense than that in samples from group 2 at 34 days after repair without the introduction of autologous precursor cells.

CONCLUSION

The sheep proved to be a good experimental model to assist in the development of research on muscle regeneration and the autologous manipulation of stem cells as a therapeutic option.

Intertester reliability of clinical shoulder instability and laxity tests in subjects with and without self-reported shoulder problems

OBJECTIVE

First, to investigate the intertester reliability of clinical shoulder instability and laxity tests, and second, to describe the mutual dependency of each test evaluated by each tester for identifying self-reported shoulder instability and laxity.

METHODS

A standardised protocol for conducting reliability studies was used to test the intertester reliability of the six clinical shoulder instability and laxity tests: apprehension, relocation, surprise, load-and-shift, sulcus sign and Gagey. Cohen's kappa (κ) with 95% CIs besides prevalence-adjusted and bias-adjusted kappa (PABAK), accounting for insufficient prevalence and bias, were computed to establish the intertester reliability and mutual dependency.

RESULTS

Forty individuals (13 with self-reported shoulder instability and laxity-related shoulder problems and 27 normal shoulder individuals) aged 18-60 were included. Fair (relocation), moderate (load-and-shift, sulcus sign) and substantial (apprehension, surprise, Gagey) intertester reliability were observed across tests (κ 0.39-0.73; 95% CI 0.00 to 1.00). PABAK improved reliability across tests, resulting in substantial to almost perfect intertester reliability for the apprehension, surprise, load-and-shift and Gagey tests (κ 0.65-0.90). Mutual dependencies between each test and self-reported shoulder problem showed apprehension, relocation and surprise to be the most often used tests to characterise self-reported shoulder instability and laxity conditions.

CONCLUSIONS

Four tests (apprehension, surprise, load-and-shift and Gagey) out of six were considered intertester reliable for clinical use, while relocation and sulcus sign tests need further standardisation before acceptable evidence. Furthermore, the validity of the tests for shoulder instability and laxity needs to be studied.

Comprehensive Examination of the Athlete's Shoulder

Context:

Shoulder pain and dysfunction are common, with patients presenting complaints to both primary and orthopaedic physicians. History and physical examination remain essential to creating a differential diagnosis, even as noninvasive imaging has improved.

Evidence Acquisition:

Literature was obtained through keyword searches based on the pathology in question (eg, rotator cuff) and the keywords physical examination using PubMed from January 1, 1980, through September 20, 2017. Additional evidence was obtained through screening references from articles identified through the PubMed searches.

Study Design:

Clinical review.

Level of Evidence:

Level 3.

Results:

A total of 7817 articles were screened for relevance. Several physical examination maneuvers have been described for each specific pathology. The Neer sign has a 75% sensitivity for subacromial impingement (SAI), while the Hawkins-Kennedy test has an 80% sensitivity. The painful arc test has an 80% specificity for SAI. The apprehension test has a hazard ratio of 2.96 for anterior shoulder instability. The Jobe test has a sensitivity of 52.6% and a specificity of 82.4% for full-thickness supraspinatus tears, confirmed on arthroscopy. The lag sign is highly sensitive and specific for combined full-thickness supraspinatus and infraspinatus tears at 97% and 93%, respectively. The Speed test has a sensitivity of 54% and specificity of 81% for biceps pathology. The anterior slide test and O’Brien active compression test have been described for superior labrum anterior posterior tears with inconsistent reliability. The cross-body adduction test has a sensitivity of 77% and a specificity of 79% for acromioclavicular joint pathology.

Conclusion:

Several physical examination maneuvers can isolate specific pathology of the shoulder, with widely ranging sensitivity and specificity.

Intra- and inter-observer reproducibility of shoulder laxity tests: Comparison of the drawer, modified drawer and load and shift tests

BACKGROUND

Conventional tests of shoulder laxity have been shown to have poor reliability due to the difficulty in palpating the subtle movements of the shoulder joint beneath the musculature. Modified drawer test that is performed while the soft tissues surrounding the shoulder are loosened has been proposed to facilitate glenohumeral joint movement and improve reliability. We hypothesised that the modified drawer test would have an improved intra- and inter-observer reproducibility in comparison to the drawer and load and shift tests. Correlation of shoulder laxity measured by these tests with generalized joint laxity was also assessed.

METHODS

Forty healthy volunteers underwent bilateral shoulder examination in the clinic using the three tests for anterior and posterior laxity assessment by a consultant shoulder surgeon and a resident. The examination was repeated three months later by the same examiners in the same cohort. Intra- and inter- observer reproducibility was calculated using Kappa values. The correlation of shoulder with generalized joint laxity was also investigated.

RESULTS

The modified drawer test showed significantly improved intra-observer reproducibility compared to the drawer test, but not to the load and shift (κ = 0.173, -0.042, and 0.009, respectively). There were no significant differences in the inter-observer reproducibility between the three tests (κ = 0.054, 0.055, and 0.056, respectively). Moderate correlation was noted between shoulder and generalized joint laxity when modified drawer test was used (r = 0.417).

CONCLUSIONS

The modified drawer test improves intra- but not inter- observer reproducibility compared to the drawer test. Shoulder laxity assessed by the modified test correlated to generalized joint laxity. The modified drawer test has an improved reproducibility and correlation to generalized joint laxity over the conventional tests.

The effects of a conservative rehabilitation program for multidirectional instability of the shoulder

BACKGROUND

Conservative management is commonly recommended as the first-line treatment for multidirectional instability (MDI) of the shoulder. Despite this, the evidence for efficacy of treatment is limited, and until recently, guidance for clinicians on conservative rehabilitation programs has been inadequate. This study evaluated the effectiveness of a physiotherapy-led exercise program for participants with MDI.

METHODS

In a single-group study design, 43 participants (16 male, 27 female; mean age, 19.8 years, standard deviation, 4.9 years) diagnosed with MDI undertook a 12-week exercise program. Primary outcome measures were the Melbourne Instability Shoulder Score, Western Ontario Shoulder Instability Index, and Oxford Shoulder Instability Score. Secondary outcomes were strength and scapular position. All measures were taken at baseline and repeated at the conclusion of the program. Test differences before and after rehabilitation were evaluated with dependent t tests and single-group effect size calculations (standardized mean difference [SMD]) to provide a measure of the magnitude of the difference.

RESULTS

Large effects were found between pre- and postrehabilitation scores on all functional instability questionnaires, with the Western Ontario Shoulder Instability Index demonstrating the largest effect (SMD, -3.04). Scapular upward rotation improved significantly in the early ranges of abduction (0°-60°), with moderate to large effects (SMDs, 0.54-0.95). All strength measures significantly improved, with large differences identified (SMDs, 0.69-2.08).

CONCLUSION

The identified improvement in functional status, shoulder muscle strength, and scapular positioning after rehabilitation allows greater confidence in the value of conservative management of MDI and informs further research by way of clinical trials in the area.

Three-dimensional kinematics of shoulder laxity examination and the relationship to clinical interpretation

Understanding clinical test kinematics improves utility of exam techniques. The purposes of this study were as follows: (1) determine inter-examiner repeatability of translation magnitude for the Anterior/Posterior Drawer and Sulcus shoulder laxity tests; (2) describe the relationships between glenohumeral joint translations and subjective grades for each laxity test; and (3) describe the relationship of overall glenohumeral joint laxity to a composite subjective score from the three laxity tests. Eleven subjects with shoulder symptomology were examined with three laxity tests. Motion was tracked with electromagnetic sensors affixed to the humerus and scapula via transcortical pins. ICCs were calculated to determine repeatability of translation magnitudes between two examiners for each test. Descriptive statistics and regression analyses were performed for comparisons of single laxity test grades with translation magnitudes and for composite subjective laxity scores and overall translation across all three tests. Inter-examiner ICCs regarding kinematic repeatability were 0.87 for Anterior Drawer, 0.84 for the Sulcus test, and not calculable for the Posterior Drawer. No linear relationships between subjective grades of individual tests and translation magnitudes were found. The relationship of overall translation with the composite subjective score from all laxity tests was r² = 0.75 (r = 0.86). Clinicians from different disciplines are capable of imparting similar translations during laxity tests. Single-test subjective laxity grades demonstrate large ranges of translation between subjects for the same grade. By combining results of three laxity tests, clinicians are capable of identifying the level of overall shoulder joint laxity in patients.

A prospective cohort study identifying risk factors for shoulder injuries in adolescent elite handball players: the Karolinska Handball Study (KHAST) study protocol

Background

Handball is a physical contact sport that includes frequent overhead throwing, and this combination leads to a high rate of shoulder injuries. Several factors have been associated with shoulder injuries in overhead athletes, but strong scientific evidence is lacking for most suggested risk factors. We therefore designed the Karolinska Handball Study (KHAST) with the aim to identify risk factors for shoulder injuries in adolescent male and female elite handball players studying at handball-profiled secondary schools in Sweden. Secondary objectives are to investigate whether shoulder function changes during the competition season and whether the physical profile of the players changes during their time in secondary school.

Methods

Players aged 15 to 19 years were included during the pre-season period of the 2014–2015 and the 2015–2016 seasons. At inclusion, players signed informed consent and filled in a questionnaire regarding playing position, playing level, previous handball experience, history of shoulder problems and athletic identity. Players also completed a detailed test battery at baseline evaluating the shoulder, neck and trunk. Players were then prospectively monitored weekly during the 2014–2015 and/or 2015–2016 competitive seasons regarding injuries and training/match workload. Results from the annual routine physical tests in the secondary school curriculum including bench press, deep squat, hand grip strength, clean lifts, squat jumps, counter movement jumps, <30 m sprints, chins, dips and Cooper’s test will be collected until the end of the competitive season 2017–2018. The primary outcome is the incidence of shoulder injuries and shoulder problems. The secondary outcome is the prevalence of shoulder injuries and shoulder problems.

Discussion

Shoulder problems are frequent among handball players and a reduction of these injuries is therefore warranted. However, in order to introduce appropriate preventive measures, a detailed understanding of the underlying risk factors is needed. Our study has a high potential to identify important risk factors for shoulder injuries in adolescent elite handball players owing to a large study sample, a high response rate, data collection during consecutive seasons, and recording of potential confounding factors.

Electronic supplementary material

The online version of this article (10.1186/s12891-017-1852-2) contains supplementary material, which is available to authorized users.

Controversies In The Surgical Management Of Shoulder Instability: Associated Soft Tissue Procedures

Background:

The glenohumeral joint is a ball-and-socket joint that is inherently unstable and thus, susceptible to dislocation. The traditional and most common anatomic finding is the Bankart lesion (anterior-inferior capsule labral complex avulsion), but there is a wide variety of anatomic alterations that can cause shoulder instability or may be present as a concomitant injury or in combination, including bone loss (glenoid or humeral head), complex capsule-labral tears, rotator cuff tears, Kim´s lesions (injuries to the posterior-inferior labrum) and rotator interval pathology.

Methods:

A review of articles related to shoulder anatomy and soft tissue procedures that are performed during shoulder instability arthroscopic management was conducted by querying the Pubmed database and conclusions and controversies regarding this injury were exposed.

Results:

Due to the complex anatomy of the shoulder and the large range of movement of this joint, a wide variety of anatomic injuries and conditions can lead to shoulder instability, specially present in young population. Recognizing and treating all of them including Bankart repair, capsule-labral plicatures, SLAP repair, circumferential approach to pan-labral lesions, rotator interval closure, rotator cuff injuries and HAGL lesion repair is crucial to achieve the goal of a stable, full range of movement and not painful joint.

Conclusion:

Physicians must be familiarized with all the lesions involved in shoulder instability, and should be able to recognize and subsequently treat them to achieve the goal of a stable non-painful shoulder. Unrecognized or not treated lesions may result in recurrence of instability episodes and pain while overuse of some of the techniques previously described can lead to stiffness, thus the importance of an accurate diagnosis and treatment when facing a shoulder instability.

Diagnosis and treatment of anteroinferior capsular redundancy associated with anterior shoulder instability using an open Latarjet procedure and capsulorrhaphy

PURPOSE

There is a paucity of data detailing management of anterior capsular redundancy (ACR) when using the Latarjet procedure for unidirectional instability. This study aimed to describe the surgical management and to assess the clinical profile of patients presenting with anterior capsular redundancy [ACR(+)] with anterior shoulder instability.

METHODS

Seventy-seven patients who had a Latarjet procedure were followed for a 55-month period. Per-operative ACR was assessed during surgery. ACR was considered present if the inferior capsular flap of a Neer T-shaft capsulorrhaphy was able to cover the superior capsular flap with the arm in the neutral position. Patients with ACR(+) received an additional Neer capsulorrhaphy, while patients with ACR(-) did not. This per-operative finding was correlated with demographics, clinical, radiological pre-operative data and surgical outcome.

RESULTS

Patients presenting with a per-operative ACR(+) were significantly associated with a sulcus sign (P < 0.001), a Beighton score >4 (P < 0.01), a low-energy instability history (P < 0.05), a predominant history of subluxations (P < 0.05), fewer Hill-Sachs lesion (P < 0.05) and a female gender (P < 0.05), but not significantly with external rotation >85°. Open standard Latarjet procedures with Neer capsulorrhaphy in ACR(+) patients showed excellent or good results and stability rate of 95 %. All patients except four who presented with a new dislocation after surgery were satisfied with their outcome. Thirteen patients (16 %) had a persistent apprehension sign at the last follow-up. ACR(+) and ACR(-) groups did not show significant difference in the mean values of Rowe, Walch-Duplay and Constant-Murley scores.

CONCLUSION

ACR correlated with a sulcus sign, Beighton score and instability history. In anterior shoulder instability associated with ACR, the Latarjet procedure with a Neer capsulorrhaphy appears a satisfactory treatment alternative to arthroscopic or open capsular shift. It decreased apprehension in comparison with Latarjet procedures without capsular repair.

LEVEL OF EVIDENCE

Cases series, treatment study, Level IV.

Effect of exercise-based management on multidirectional instability of the glenohumeral joint: a pilot randomised controlled trial protocol

INTRODUCTION

The most commonly recommended treatment for multidirectional instability (MDI) of the shoulder is exercise. Despite this recommendation, there is limited evidence to support the effectiveness of exercise. The aim of this paper is to describe a pilot randomised controlled trial comparing the effectiveness of 2 exercise programmes on outcomes of participants with MDI.

METHODS AND ANALYSIS

Consenting participants between 12 and 35 years, with non-traumatic MDI will be randomly allocated to participate in either the Rockwood Instability programme or the Watson MDI programme. Both programmes involve 1 consultation per week for 12 weeks with a physiotherapist to prescribe and progress a home exercise programme. Outcomes will be assessed at baseline, 6, 12, 24 and 52 weeks. Primary outcome measures include the Melbourne Instability Shoulder Score and Western Ontario Shoulder Index. Secondary outcomes include scapular coordinates, scapular upward rotation angles, muscle strength, symptomatic onset, limiting factor and angle of limiting factor in abduction range, incidence of complete glenohumeral joint dislocation, global rating of change, satisfaction scores, the Orebro Musculoskeletal Pain Questionnaire, adverse events and compliance with the home exercise programme. Data will be analysed on intention-to-treat principles and a per protocol basis.

DISCUSSION

This trial will evaluate whether there are differences in outcomes between the Rockwood and the Watson MDI programmes for participants with MDI.

ETHICS AND DISSEMINATION

Participant confidentiality will be maintained with publication of results. Ethics approval: Faculty of Health Sciences (FHEC12/201).

TRIAL REGISTRATION NUMBER

ACTRN12613001240730; Pre-results.

Evaluation of functional results from shoulders after arthroscopic repair of complete rotator cuff tears associated with traumatic anterior dislocation

Objective

To evaluate the clinical outcome of arthroscopic rotator cuff fixation and, when present, simultaneous repair of the Bankart lesion caused by traumatic dislocation; and to assess whether the size of the rotator cuff injury caused by traumatic dislocation has any influence on the postoperative clinical outcomes.

Methods

Thirty-three patients with traumatic shoulder dislocation and complete rotator cuff injury, with at least two years of follow up, were retrospectively evaluated. For analysis purposes, the patients were divided into groups: presence of fixed Bankart lesion or absence of this lesion, and rotator cuff lesions smaller than 3.0 cm (group A) or greater than or equal to 3.0 cm (group B). All the patients underwent arthroscopic repair of the lesions and were evaluated postoperatively by means of the UCLA (University of California at Los Angeles) score and strength measurements.

Results

The group with Bankart lesion repair had a postoperative UCLA score of 33.96, while the score of the group without Bankart lesion was 33.7, without statistical significance (p = 0.743). Group A had a postoperative UCLA score of 34.35 and group B, 33.15, without statistical significance (p = 0.416).

Conclusion

The functional outcomes of the patients who only presented complete rotator cuff tearing after traumatic shoulder dislocation, which underwent arthroscopic repair, were similar to the outcomes of those who presented an associated with a Bankart lesion that was corrected simultaneously with the rotator cuff injury. The extent of the original rotator cuff injury did not alter the functional results in the postoperative evaluation.

International survey and surgeon's preferences in diagnostic work-up towards treatment of anterior shoulder instability

PURPOSE

Recurrent anterior shoulder instability after surgical treatment can be caused by bony defects. Several diagnostic tools have been designed to measure the extent of these bony lesions. Currently, there is no consensus which measurement tool to use and decide which type of surgery is most appropriate. We therefore performed an evaluation of agreement in surgeons' preference of diagnostic work-up and surgical treatment of anterior shoulder instability.

METHODS

An international survey was conducted amongst orthopaedic shoulder surgeons. The survey contained questions about surgeons' experience, clinical and radiological examination and the subsequent treatment for anterior shoulder instability. Descriptive statistics were used to present the data, and percentages of responding surgeons were calculated.

RESULTS

The questionnaire was completed by 197 delegates from 46 countries. 55 % of the respondents think evidence in current literature is sufficient on diagnostic work-up for anterior shoulder instability. Anamnestic, number of dislocations was most frequently asked (by 95 % of respondents), the most frequently used test is the apprehension test (91 %). For imaging, conventional X-ray in various directions was most performed, followed by MR arthrography and plane CT scan respectively. The responding surgeons perform surgery (labrum repair or Latarjet) in 51 % of the patients. A median of 25 % glenoid bone loss was given by the respondents, as cut-off from when to perform a bony repair.

CONCLUSION

Many different diagnostic examinations for assessing shoulder instability are used and a high variety is seen in the use of diagnostic tools. Also no consensus is seen in the use of different surgical options (arthroscopic and open procedures). This implies the need for more research on diagnostic imaging and the correlation with specific subsequent surgical treatment.

LEVEL OF EVIDENCE

Survey, level of evidence IV.

Rotator cuff biology and biomechanics: a review of normal and pathological conditions

The glenohumeral joint is a complex anatomic structure commonly affected by injury such as tendinopathy and rotator cuff tears. This review presents an up-to-date overview of research on tendon biology and structure, shoulder joint motion and stability, tendon healing, and current and potential future repair strategies. Recent studies have provided information demonstrating the serious impact on uninjured tissues after a rotator cuff tear or other cause of altered shoulder joint mechanics. Another major focus of recent research is biological augmentation of rotator cuff repair with the goal of successfully reinstating normal tendon-to-bone structure. To effectively treat shoulder pathologies, clinicians need to understand normal tendon biology, the healing process and environment, and whole shoulder stability and function.

Identification and treatment of existing copathology in anterior shoulder instability repair

Recurrent anterior instability is a common finding after traumatic glenohumeral dislocation in the young, athletic patient population. A variety of concomitant pathologies may be present in addition to the classic Bankart lesion, including glenoid bone loss; humeral head bone loss; rotator interval pathology; complex/large capsular injuries including humeral avulsions of the glenohumeral ligaments (HAGL lesions), SLAP tears, near circumferential labral tears, and anterior labral periosteal sleeve avulsions (ALPSA lesions); and rotator cuff tears. Normal anatomic variations masquerading as pathology also may be present. Recognition and treatment of these associated pathologies are necessary to improve function and symptoms of pain and to confer anterior shoulder stability. This review will focus on the history, physical examination findings, imaging findings, and recommended treatment options for common sources of copathology in anterior shoulder instability repair.

Do stingers affect scapular kinematics in rugby players?

BACKGROUND

Scapular dyskinesis is observed in subjects with pathologic conditions of the shoulder; however, there is limited information about the factors related to scapular dyskinesis among participants in rugby. The purpose of this study was to investigate the incidence, reliability, and relationships between scapular dyskinesis and variables related to the shoulder in high-school rugby players.

METHODS

A total of 164 Japanese high-school rugby players were evaluated with questionnaires, physical examinations, and a video analysis during their preseason. After evaluation of the inter-rater reliability of a classification of scapular dyskinesis, the outcomes were analyzed to assess the relationships between scapular dyskinesis and other variables during the preseason. The data were assessed with a logistic regression analysis calculating the odds ratios (OR).

RESULTS

The inter-rater reliability among 3 blinded observers based on the Fleiss κ value and percentage agreement was .52 and 79.0%, respectively, which indicates that the method is moderately reliable. Scapular dyskinesis was identified in 16 (10.1%) shoulders among 159 players, with type I being prominent. A multivariate logistic regression analysis revealed that a type I dyskinesis was significantly associated with a past history of stingers with projected pain to the affected side of the shoulder (OR, 3.7) and the player's competitive grade at the time of the survey (OR, 3.9).

CONCLUSIONS

Scapular dyskinesis is significantly associated with a past history of stingers. This suggests that stingers are a causative factor of scapular dyskinesis in the rugby population. Our method of evaluating scapular dyskinesis in collision athletes exhibits moderate reliability.

Physical examination of the shoulder

This article summarizes the overall assessment of the shoulder joint and seeks to help direct clinicians to diagnose shoulder pathology using standard and specific physical examinations. The history and standard examination can prompt the examiner to focus on specific tests to further evaluate the shoulder and limit the differential diagnoses. An appropriate and directed shoulder physical examination allows the clinician to focus on further diagnostic strategies and treatment options for the patient.

Rotator cuff tear and glenohumeral instability : a systematic review

BACKGROUND

The rotator cuff plays a significant role in the static and dynamic stability of the glenohumeral joint. Rotator cuff tears may occur after shoulder dislocations, whether in younger athletes or older patients with age-related tendon degeneration. Untreated tears may cause persistent pain, dysfunction, instability, and degenerative changes. A thorough understanding of when to look for rotator cuff tears after shoulder dislocations and how best to manage them may decrease patients' pain and improve function.

QUESTIONS/PURPOSES

We systematically reviewed the available literature to better understand (1) when a rotator cuff tear should be suspected after a dislocation, (2) whether surgical or nonsurgical approaches result in better scores for pain and satisfaction in patients with rotator cuff tears resulting from shoulder dislocations, and (3) whether intraarticular lesions, rotator cuff tears, or both should be addressed when surgery is performed.

METHODS

We systematically searched MEDLINE(®), CINAHL, and EMBASE for studies published from 1950 to 2012. We included studies reporting outcomes after treatment in patients with rotator cuff tears and shoulder dislocations. We excluded case reports, studies without any treatment, and studies about patients treated with arthroplasty. Five Level III and six Level IV studies were ultimately selected for review.

RESULTS

Patients with persistent pain or dysfunction after a shoulder dislocation often had a concomitant rotator cuff tear. Surgical repair resulted in improved pain relief and patient satisfaction compared to nonoperative management. Repair of the rotator cuff, along with concomitant capsulolabral lesions, helped restore shoulder stability. While these findings are based on Level III and IV evidence, better long-term studies with larger cohorts are needed to strengthen evidence-based recommendations.

CONCLUSIONS

Persistent pain and dysfunction after a shoulder dislocation should prompt evaluation of the rotator cuff, especially in contact or overhead athletes, patients older than 40 years, or those with nerve injury. Surgery should be considered in the appropriately active patient with a rotator cuff tear after dislocation. While the current literature suggests improved stability and function after surgical repair of the rotator cuff, higher-quality prospective studies are necessary to make definitive conclusions.

Effects of external rotation on anteroposterior translations in the shoulder: a pilot study

BACKGROUND

Using physical examination to make the diagnosis of shoulder instability can be difficult, because typical examination maneuvers are qualitative, difficult to standardize, and not reproducible. Measuring shoulder translation is especially difficult, which is a particular problem, because measuring it inaccurately may result in improper treatment of instability.

QUESTIONS/PURPOSES

The objective of this study was to use a magnetic motion tracking system to quantify the effects of external rotation of the abducted shoulder on a simulated simple translation test in healthy subjects. Specifically, we hypothesized that (1) increasing external rotation of the abducted shoulder would result in decreasing translation; (2) intraobserver repeatability would be less than 2 mm at all external rotation positions; and (3) mean side-to-side differences would be less than 2 mm at all external rotation positions.

METHODS

The intraobserver repeatability and side-to-side differences of AP translation were quantified with a noninvasive magnetic motion tracking system and automated data analysis routine in nine healthy subjects at four positions of external rotation with the arm abducted. A shoulder positioning apparatus was used to maintain the desired arm position.

RESULTS

No differences in translations between the positions of external rotation were found (p = 0.48). Intraobserver repeatability was 1.1 mm (SD, 0.8 mm) and mean side-to-side differences were small: 2.7 mm (SD, 2.8 mm), 2.8 mm (SD, 1.8 mm), 2.5 mm (SD, 1.8 mm), and 4.0 mm (SD, 2.6 mm) at 0°, 20°, 40°, and 60° of external rotation, respectively.

CONCLUSIONS

The intraobserver repeatability was strong and the side-to-side differences in translation were small with the magnetic motion tracking system, which is encouraging for development of an improved quantitative test to assess shoulder translation for fast and low-cost diagnosis of shoulder instability.

CLINICAL RELEVANCE

Clinicians may not have to position the contralateral, normal, abducted shoulder in precisely the same position of external rotation as the injured shoulder while performing side-to-side comparisons.

Management of humeral and glenoid bone loss in recurrent glenohumeral instability

Recurrent shoulder instability and resultant glenoid and humeral head bone loss are not infrequently encountered in the population today, specifically in young, athletic patients. This review on the management of bone loss in recurrent glenohumeral instability discusses the relevant shoulder anatomy that provides stability to the shoulder joint, relevant history and physical examination findings pertinent to recurrent shoulder instability, and the proper radiological imaging choices in its workup. Operative treatments that can be used to treat both glenoid and humeral head bone loss are outlined. These include coracoid transfer procedures and allograft/autograft reconstruction at the glenoid, as well as humeral head disimpaction/humeroplasty, remplissage, humeral osseous allograft reconstruction, rotational osteotomy, partial humeral head arthroplasty, and hemiarthroplasty on the humeral side. Clinical outcomes studies reporting general results of these techniques are highlighted.

MR arthrography including abduction and external rotation images in the assessment of atraumatic multidirectional instability of the shoulder

OBJECTIVE

To evaluate diagnostic signs and measurements in the assessment of capsular redundancy in atraumatic multidirectional instability (MDI) of the shoulder on MR arthrography (MR-A) including abduction/external rotation (ABER) images.

METHODS

Twenty-one MR-A including ABER position of 20 patients with clinically diagnosed MDI and 17 patients without instability were assessed by three radiologists. On ABER images, presence of a layer of contrast between the humeral head (HH) and the anteroinferior glenohumeral ligament (AIGHL) (crescent sign) and a triangular-shaped space between the HH, AIGHL and glenoid (triangle sign) were evaluated; centring of the HH was measured. Anterosuperior herniation of the rotator interval (RI) capsule and glenoid version were determined on standard imaging planes.

RESULTS

The crescent sign had a sensitivity of 57 %/62 %/48 % (observers 1/2/3) and specificity of 100 %/100 %/94 % in the diagnosis of MDI. The triangle sign had a sensitivity of 48 %/57 %/48 % and specificity of 94 %/94 %/100 %. The combination of both signs had a sensitivity of 86 %/90 %/81 % and specificity of 94 %/94 %/94 %. A positive triangle sign was significantly associated with decentring of the HH. Measurements of RI herniation, RI width and glenoid were not significantly different between both groups.

CONCLUSIONS

Combined assessment of redundancy signs on ABER position MR-A allows for accurate differentiation between patients with atraumatic MDI and patients with clinically stable shoulders; measurements on standard imaging planes appear inappropriate.

KEY POINTS

MR arthrography has the possibility to accurately identify patients with atraumatic MDI. Imaging of the shoulder in abduction and external rotation provides additive information. Capsular enlargement of the shoulder can be diagnosed on MR arthrography.

The interobserver reliability in diagnosing osseous lesions after first-time anterior shoulder dislocation comparing plain radiographs with computed tomography scans

BACKGROUND

Recurrence after first-time traumatic anterior shoulder dislocation is frequent. The prevalence of glenoid bone loss ranges from 41% after a first-time dislocation to 86% with recurrent dislocation. Postoperative recurrence can occur in up to 10% of cases. Thus, misdiagnosis of bony glenoid rim lesions has been assumed a major cause for failure. We evaluated the interobserver reliability of radiologic diagnoses after first-time traumatic shoulder dislocation based on radiographs and computed tomography (CT) images.

METHODS

Digital radiographs before and after reduction and CT images after reduction of 20 patients with a first-time shoulder dislocation were assessed by 6 observers. It was recorded whether they diagnosed a lesion at the greater tuberosity, a lesion at the glenoid rim, a Hill-Sachs lesion, or any other skeletal pathology. The average agreement among the investigators was evaluated, and radiographic diagnoses were compared with those based on CT images.

RESULTS

Of the 10 cases that presented with a glenoid rim fracture, each investigator had overlooked at least 1 fracture (range, 1-4) on the radiographs. No investigator had diagnosed all 8 Hill-Sachs lesions on the presented images. The average overall agreement among the investigators and corresponding sensitivity and specificity were calculated. Agreement of diagnoses based on radiographs with those based on CT images was lowest for glenoid rim fractures and Hill-Sachs lesions.

CONCLUSION

Radiographs seem inferior to CT scans for assessing osseous lesions especially at the glenoid rim. We suggest performing a CT scan of the shoulder after primary dislocation to apply the correct treatment early and potentially avoid further dislocations.

Reconstruction of posterior glenoid deficiency using distal tibial osteoarticular allograft

Posterior shoulder instability with glenoid deficiency is a rare entity and its surgical treatment is challenging. Reconstructive techniques have focused on extra-articular structural bone transfer that obstructs humeral translation and thereby prevents glenohumeral dislocation. However, long-term results are not as promising. In this report, the authors describe a technique for anatomic posterior glenoid reconstruction using an osteoarticular distal tibia allograft in two patients including their outcomes after 2 years. Level of evidence IV.

Evaluation of dislocation position in patients with recurrent anterior shoulder dislocation

BACKGROUND

The usual mechanism of anterior shoulder dislocation is widely believed to be a combination of glenohumeral joint abduction, extension, and external rotation forces, even though no published reports to date have investigated the arm position of anterior shoulder dislocation in detail. Understanding the exact position of anterior shoulder dislocations is important for the management of anterior shoulder instability.

MATERIALS AND METHODS

The study included 40 shoulders of 38 patients (32 males, 6 females), aged 28.0 (range, 13-73) years with symptomatic post-traumatic recurrent anterior shoulder instability. While patients were under general anesthesia, but before shoulder-stabilizing surgery, we evaluated the angle of external rotation with 90° elevation in the scapular plane at which the humeral head showed anterior translations over the glenoid rim.

RESULTS

The center of anterior instability at 90° elevation in the scapular plane was at 25.9° of external rotation. Anterior translations were detected in the range of 3.4° of internal rotation to 55.1° of external rotation, and no shoulders (except one) showed anterior translation at maximal external rotation.

CONCLUSIONS

Gross anterior translation was seen in the middle range of rotation at approximately 25° of external rotation, and anterior translation decreased close to the end of external and internal rotation. Shoulders with grade III translation showed anterior translation in a wider range of rotation, especially in external rotation. These data will help to further our understanding of the management and the prevention of anterior shoulder dislocations.

Evaluation and management of posterior shoulder instability

CONTEXT

Posterior shoulder instability is a commonly misdiagnosed disorder in many competitive athletes.

TYPE OF STUDY

Clinical review.

EVIDENCE ACQUISITION

Relevant studies on posterior shoulder instability from 1950 to 2010 in PubMed and Cochrane databases were reviewed.

RESULTS

A total of 107 studies were reviewed.

CONCLUSION

Patients who have undergone at least 6 months of physical therapy and still experience instability symptoms should be considered for surgical stabilization directed at their underlying pathology.