The Influence of Glenoid Bone Loss and Graft Positioning on Graft and Cartilage Contact Pressures After the Latarjet Procedure.

BACKGROUND: Glenohumeral joint contact loading before and after glenoid bone grafting for recurrent anterior instability remains poorly understood. PURPOSE: To develop a computational model to evaluate the influence of glenoid bone loss and graft positioning on graft and cartilage contact pressures after the Latarjet procedure. STUDY DESIGN: Controlled laboratory study. METHODS: A finite element model of the shoulder was developed using kinematics, muscle and glenohumeral joint loading of 6 male participants. Muscle and joint forces at 90° of abduction and external rotation were calculated and employed in simulations of the native shoulder, as well as the shoulder with a Bankart lesion, 10% and 25% glenoid bone loss, and after the Latarjet procedure. RESULTS: A Bankart lesion as well as glenoid bone loss of 10% and 25% significantly increased glenoid and humeral cartilage contact pressures compared with the native shoulder (P < .05). The Latarjet procedure did not significantly increase glenoid cartilage contact pressure. With 25% glenoid bone loss, the Latarjet procedure with a graft flush with the glenoid and the humerus positioned at the glenoid half-width resulted in significantly increased humeral cartilage contact pressure compared with that preoperatively (P = .023). Under the same condition, medializing the graft by 1 mm resulted in humeral cartilage contact pressure comparable with that preoperatively (P = .097). Graft lateralization by 1 mm resulted in significantly increased humeral cartilage contact pressure in both glenoid bone loss conditions (P < .05). CONCLUSION: This modeling study showed that labral damage and greater glenoid bone loss significantly increased glenoid and humeral cartilage contact pressures in the shoulder. The Latarjet procedure may mitigate this to an extent, although glenoid and humeral contact loading was sensitive to graft placement. CLINICAL RELEVANCE: The Latarjet procedure with a correctly positioned graft should not lead to increased glenohumeral joint contact loading. The present study suggests that lateral graft overhang should be avoided, and in the situation of large glenoid bone defects, slight medialization (ie, 1 mm) of the graft may help to mitigate glenohumeral joint contact overloading.

Shoulder joint arthroplasty in young patients: Analysis of 8742 patients from the Australian Orthopaedic Association National Joint Replacement Registry.

Background: Shoulder replacement is a reliable treatment for the relief of pain and improvement of function in patients with glenohumeral arthritis, rotator cuff arthropathy, osteonecrosis and fracture. Limited data is available comparing revision rates for the different types of shoulder replacement when used in younger patients. This study aims to compare the survivorship of hemi resurfacing, stemmed hemiarthroplasty, total shoulder arthroplasty and reverse total shoulder arthroplasty in younger patients using data from a large national arthroplasty registry. Methods: Data from the Australian Orthopaedic Association National Joint Replacement Registry was obtained for the period 16 April 2004-31 December 2018. The study population included all shoulder arthroplasty patients aged <65 years. These were stratified into two groups: <55 years and 55-64 years. A total of 8742 primary shoulder arthroplasty procedures were analysed (1936 procedures in the <55 years and 6806 in the 55-64 years age group). Results: In the <55 years age group, there was no difference in revision rate for total shoulder arthroplasty versus reverse total shoulder arthroplasty at any time point. Reverse total shoulder arthroplasty had a lower revision rate after six months when compared to hemi resurfacing (HRA) (p = 0.031). Also, reverse total shoulder arthroplasty had a higher early rate of revision in the first 12 months compared to hemiarthroplasty (p = 0.018). However, from 2 years reverse total shoulder arthroplasty had a lower revision rate overall (p = 0.029).In the 55-64 years patient age group, reverse total shoulder arthroplasty had a lower earlier revision rate. This was statistically significant compared to hemi resurfacing (HRA) (p = 0.028), hemiarthroplasty (p = 0.049) and total shoulder arthroplasty (p < 0.001). Conclusion: This study demonstrated that for patients aged <55 years there was no significant difference in the rate of revision when total shoulder arthroplasty and reverse total shoulder arthroplasty were compared. reverse total shoulder arthroplasty had a lower rate of revision when compared to hemi resurfacing and hemiarthroplasty after 2 years. reverse total shoulder arthroplasty had the lowest comparative revision rate in patients aged 55-64 years overall.

Survivorship of shoulder arthroplasty in young patients with osteoarthritis: an analysis of the Australian Orthopaedic Association National Joint Replacement Registry.

BACKGROUND: The treatment of shoulder osteoarthritis in the young patient remains challenging. The higher functional demands and higher expectations of the young patient cohort are often coupled with increased failure and revision rates. Consequently, shoulder surgeons are faced with a unique challenge with implant selection. The aim of this study was to compare the survivorship and reasons for revision of 5 classes of shoulder arthroplasty in patients aged <55 years with a primary diagnosis of osteoarthritis by use of data from a large national arthroplasty registry. METHODS: The study population included all primary shoulder arthroplasty procedures undertaken for osteoarthritis in patients aged <55 years and reported to the registry between September 1999 and December 2021. Procedures were grouped into the following classes: total shoulder arthroplasty (TSA), hemiarthroplasty resurfacing (HRA), hemiarthroplasty stemmed metallic head (HSMH), hemiarthroplasty stemmed pyrocarbon head (HSPH), and reverse total shoulder arthroplasty (RTSA). The outcome measure was the cumulative percent revision, which was defined using Kaplan-Meier estimates of survivorship to describe the time to the first revision. Hazard ratios (HRs) were calculated from Cox proportional hazards models, adjusting for age and sex, to compare revision rates among groups. RESULTS: There were 1564 shoulder arthroplasty procedures in patients aged <55 years, of which 361 (23.1%) were HRA, 70 (4.5%) were HSMH, 159 (10.2%) were HSPH, 714 (45.7%) were TSA, and 260 (16.6%) were RTSA. HRA had a higher rate of revision than RTSA after 1 year (HRA = 2.51 (95% CI 1.30, 4.83), P = .005), with no difference prior to that time. In addition, HSMH had a higher rate of revision than RTSA for the entire period (HR, 2.69 [95% confidence interval, 1.28-5.63], P = .008). There was no significant difference in the rate of revision for HSPH and TSA when they were compared with RTSA. Glenoid erosion was the most common cause of revision for HRA (28.6% of revisions) and HSMH (50%). Instability/dislocation was the leading cause of revision for RTSA (41.7%) and HSPH (28.6%), and for TSA, the majority of revisions were for either instability/dislocation (20.6%) or loosening (18.6%). CONCLUSION: These results should be interpreted within the context of the lack of availability of long-term data on RTSA and HSPH stems. RTSA outperforms all implants regarding revision rates at mid-term follow-up. The high early dislocation rate associated with RTSA, as well as the lack of revision options available to address this, indicates that careful selection of patients and a greater appreciation of anatomic risk factors are needed in the future.

Validation of a Novel Patient Specific CT-Morphometric Technique for Quantifying Bone Graft Resorption Following the Latarjet Procedure.

Bone graft resorption following the Latarjet procedure has received considerable concern. Current methods quantifying bone graft resorption rely on two-dimensional (2D) CT-scans or three-dimensional (3D) techniques, which do not represent the whole graft volume/resorption (i.e., 2D assessment) or expose patients to additional radiation (i.e., 3D assessment) as this technique relies on early postoperative CT-scans. The aim of the present study was to develop and validate a patient-specific, CT-morphometric technique combining image registration with 3D CT-reconstruction to quantify bone graft resorption following the Latarjet procedure for recurrent anterior shoulder instability. Pre-operative and final follow-up CT-scans were segmented to digitally reconstruct 3D scapula geometries. A virtual Latarjet procedure was then conducted to model the timepoint-0 graft volume, which was compared with the final follow-up graft volume. Graft resorption at final follow-up was highly correlated to the 2D gold standard-technique by Zhu (Kendall tau coefficient = 0.73; p < 0.001). The new technique was also found to have excellent inter- and intra-rater reliability (ICC values, 0.931 and 0.991; both p < 0.001). The main finding of this study is that the technique presented is a valid and reliable method that provides the advantage of 3D-assessment of graft resorption at long-term follow-up without the need of an early postoperative CT-scan.

Case Report: Midshaft clavicle fracture with concomitant high grade (Type V) acromioclavicular joint dislocation.

Introduction: Concomitant acromioclavicular joint dislocation and midshaft clavicle fracture are rare injuries, generally resulting from high energy trauma, with limited previous experience in management. Case: A 30 year old male presented following a pushbike accident. He had suffered a head on collision with another cyclist. Radiographic examination demonstrated a displaced midshaft clavicle fracture with a Rockwood Type V acromioclavicular joint dislocation. Operative management was undertaken using a dual plating technique. At six month follow up the patient demonstrated full range of motion and had no pain. Conclusion: Appropriate radiographic evaluation and careful intraoperative assessment are required using the principles of management for acromioclavicular joint injuries, along with stabilization of the mid-clavicular fracture to reduce the risk of non-union.

Factors Influencing Acromial and Scapular Spine Strain after Reverse Total Shoulder Arthroplasty: A Systematic Review of Biomechanical Studies.

BACKGROUND: Acromial and scapular spine fractures after reverse total shoulder arthroplasty (RTSA) can be devastating complications leading to substantial functional impairments. The purpose of this study was to review factors associated with increased acromial and scapular spine strain after RTSA from a biomechanical standpoint. METHODS: A systematic review of the literature was conducted based on PRISMA guidelines. PubMed, Embase, OVID Medline, and CENTRAL databases were searched and strict inclusion and exclusion criteria were applied. Each article was assessed using the modified Downs and Black checklist to appraise the quality of included studies. Study selection, extraction of data, and assessment of methodological quality were carried out independently by two of the authors. Only biomechanical studies were considered. RESULTS: Six biomechanical studies evaluated factors associated with increased acromial and scapular spine strain and stress. Significant increases in acromial and scapular spine strain were found with increasing lateralization of the glenosphere in four of the included studies. In two studies, glenosphere inferiorization consistently reduced acromial strain. The results concerning humeral lateralization were variable between four studies. Humeral component neck-shaft angle had no significant effect on acromial strain as analysed in one study. One study showed that scapular spine strain was significantly increased with a more posteriorly oriented acromion (55° vs. 43°; p < 0.001). Another study showed that the transection of the coracoacromial ligament increased scapular spine strain in all abduction angles (p < 0.05). CONCLUSIONS: Glenoid lateralization was consistently associated with increased acromial and scapular spine strain, whereas inferiorization of the glenosphere reduced strain in the biomechanical studies analysed in this systematic review. Humeral-sided lateralization may increase or decrease acromial or scapular spine strain. Independent of different design parameters, the transection of the coracoacromial ligament resulted in significantly increased strains and scapular spine strains were also increased when the acromion was more posteriorly oriented. The results found in this systematic review of biomechanical in-silico and in-vitro studies may help in the surgical planning of RTSA to mitigate complications associated with acromion and scapular spine fracture.

Mid-term outcomes of pyrolytic carbon humeral resurfacing hemiarthroplasty compared with metal humeral resurfacing and metal stemmed hemiarthroplasty for osteoarthritis in young patients: analysis from the Australian Orthopaedic Association National Joint Replacement Registry.

BACKGROUND: The optimal surgical management of glenohumeral osteoarthritis in young patients remains an unsolved problem. Humeral resurfacing hemiarthroplasty and stemmed hemiarthroplasty using metallic heads are 2 surgical options that avoid the complications of loosening or wear of the glenoid component seen in total shoulder arthroplasty. Despite the potential benefits, improvement in survivorship has not been demonstrated from joint registry studies or other studies at mid-term follow-up. This is predominantly because of glenoid erosion and pain that occur when the metal resurfaced head articulates with the native glenoid. The use of pyrolytic carbon (pyrocarbon) as a resurfacing material has been proposed as an alternative bearing surface thought to reduce glenoid erosion owing to a marked reduction in wear rates in vitro. This study aimed to compare the survivorship of shoulder hemi-resurfacing using pyrocarbon with shoulder hemi-resurfacing and stemmed hemiarthroplasty using metallic heads. METHODS: Data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) were analyzed for all patients aged <55 years who had undergone a primary shoulder replacement for osteoarthritis from April 16, 2004, to December 31, 2019. The outcomes of shoulder procedures using pyrocarbon hemi-resurfacing were compared with procedures using metal hemi-resurfacing and metal stemmed hemiarthroplasty. The reasons for revision in each arthroplasty class were analyzed. The analyses were undertaken using Kaplan-Meier estimates of survivorship and hazard ratios (HRs) from Cox proportional hazards models. RESULTS: We analyzed 393 primary shoulder procedures, of which 163 were pyrocarbon hemi-resurfacing procedures, 163 were metal hemi-resurfacing procedures, and 67 were metal stemmed hemiarthroplasties.The cumulative percentage of revision at 6 years was 8.9% for pyrocarbon hemi-resurfacing, 17.1% for metal hemi-resurfacing, and 17.5% for metal stemmed hemiarthroplasty. Pyrocarbon hemi-resurfacing prostheses had a statistically lower revision rate than other hemi-resurfacing prostheses (HR, 0.41; 95% confidence interval, 0.18-0.93; P = .032). Pain, prosthesis fracture, and infection were the key reasons for revision. No pyrocarbon hemi-resurfacing cases were revised for glenoid erosion. In male patients, pyrocarbon humeral resurfacing had a lower cumulative percentage of revision compared with metal stemmed hemiarthroplasty (HR, 0.32; 95% confidence interval, 0.11-0.93; P = .037). CONCLUSION: Pyrocarbon humeral resurfacing arthroplasty had statistically lower revision rates at mid-term follow-up in patients aged <55 years compared with other hemi-resurfacing procedures.

Stress reactions and fractures around the elbow in athletes.

Stress fractures of the upper limb affect athletes from a wide range of sports. Athletes involved in throwing sports are particularly susceptible along with athletes from sports involving high repetitive and compressive loads such as gymnastics. Diagnosis can be made from clinical history, examination and radiography in some cases however MRI imaging is often required for definitive diagnosis. The mainstay of management is rest and activity modification however advanced pathology often requires surgical management for successful resolution and return to play. In the elbow, the bones susceptible to excessive stress in sport are the distal humerus, the olecranon process of the ulna, the coronoid process of the ulna, the sublime tubercle and the radial head. In immature patients, medial epicondyle apophysis is the most common location. The article presents a narrative review of the literature.

Patients Undergoing Shoulder Stabilization Procedures Do Not Accurately Recall Their Preoperative Symptoms at Short- to Midterm Follow-up.

BACKGROUND: A patient's ability to recall symptoms is poor in some elderly populations, but we considered that the recall of younger patients may be more accurate. The accuracy of recall in younger patients after surgery has not been reported to date. PURPOSE: To assess younger patients' abilities to recall their preoperative symptoms after having undergone shoulder stabilization surgery. We used 2 disease-specific, patient-reported outcome measures (PROMs)-the Western Ontario Shoulder Instability Index (WOSI) and the Melbourne Instability Shoulder Score (MISS)-at a period of up to 2 years postoperatively. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Participants (N = 119) were stratified into 2 groups: early recall (at 6-8 months postoperatively; n = 58) and late recall (at 9-24 months postoperatively; n = 61). All patients completed the PROMs with instructions to recall preoperative function. The mean and absolute differences between the preoperative scores and recalled scores for each PROM were compared using paired t tests. Correlations between the actual and recalled scores of the subsections for each PROM were calculated using an intraclass correlation coefficient (ICC). The number of individuals who recalled within the minimal detectable change (MDC) of each PROM was calculated. RESULTS: Comparison between the means of the actual and recalled preoperative scores for both groups did not demonstrate significant differences (early recall differences, MISS 1.05 and WOSI -38.64; late recall differences, MISS -0.25 and WOSI -24.02). Evaluation of the absolute difference, however, revealed a significant difference between actual and recalled scores for both the late and early groups (early recall absolute differences, MISS 12.26 and WOSI 216.71; late recall absolute differences, MISS 12.84 and WOSI 290.08). Average absolute differences were above the MDC scores of both PROMs at both time points. Subsections of each PROM demonstrated weak to moderate correlations between actual and recalled scores (ICC range, 0.17-0.61). Total scores for the PROMs reached moderate agreement between actual and recalled scores. CONCLUSION: Individual recall after shoulder instability surgery was not accurate. However, the mean recalled PROM scores of each group were not significantly different from the actual scores collected preoperatively, and recall did not deteriorate significantly over 2 years. This suggests that recall of the individual, even in this younger group, cannot be considered accurate for research purposes.

Efficacy of Primary Repair in Professional Athletes with Chronic Radial Collateral Ligament Injuries of Thumb Metacarpophalangeal Joint.

Background: Management of grade III injuries of the radial collateral ligament (RCL) of the thumb is controversial. These injuries are often treated with early surgery. However, early surgery may not be practical for the professional athlete. We report on the outcome of delayed primary repair of chronic RCL injuries without the use of tendon grafts or tendon transfers. Methods: Twelve elite professional athletes with 15 soft tissue RCL injuries who underwent delayed surgery (greater than 6 weeks) were included in this study. Athletes were managed with splinting and ongoing play during the sporting season, and underwent surgery at the conclusion of the season. Mean duration from injury to surgery was 5 months. Mean follow-up was 4.2 years after surgery. Patient-report outcome measures including pain, satisfaction rating, and disability of the arm, shoulder and hand (DASH) scores were collected. Examination findings including range of motion, laxity, and grip and pinch strength were also measured. Return-to-play data were collected for all athletes. Results: The RCL was able to be primarily repaired with suture anchors in all cases. All twelve patients were able to return to competitive play at the same pre-injury professional level. Post-operative joint function such as range of motion and laxity were comparable to the unaffected contralateral side, as were grip and lateral pinch strengths. Tip-pinch strength is lower compared to the unaffected side, but is comparable to age and sex-matched reference group. Conclusions: Delayed primary repair of the RCL is a viable option and results in satisfactory long-term outcomes. This option may be more preferable to the professional athlete who wishes to avoid surgery during the sporting season.

Minimizing Propionibacterium acnes contamination in shoulder arthroplasty: use of a wound protector.

BACKGROUND: Propionibacterium acnes may be transmitted from the subdermal tissues to the deeper tissues during shoulder arthroplasty surgery, resulting in deep infection. The aim of this prospective, clinical study was to determine whether the use of a wound protector drape can lower the incidence of P. acnes in the wound during shoulder arthroplasty surgery. METHODS: For a consecutive series of 47 patients undergoing shoulder arthroplasty, a wound protector drape was used during surgery, to isolate the subdermal layer from the surgeons' hands, retractors and other instruments. Microbiological swabs were taken both from the subdermal layer and the exposed drape to determine the incidence of P. acnes at both sites. RESULTS: The overall incidence of P. acnes in the subdermal layer was 23%. A fivefold decrease in the incidence of P. acnes in the exposed superficial layer was demonstrated by use of the wound protector drape. CONCLUSION: Use of a wound protector drape to isolate the superficial tissue layer from the surgeons' gloves, instruments and retractors decreases the incidence of P. acnes in the surgical field. This may result in a decreased rate of transmission to the deeper tissues, and a decreased rate of P. acnes deep infection.

The Specific AC Score (SACS): a new and validated method of assessment of isolated acromioclavicular joint pathology.

BACKGROUND: Acromioclavicular (AC) joint (ACJ) pathology is a common cause of shoulder dysfunction, and treatment recommendations vary. When the efficacy of treatment is evaluated, the ability to measure outcomes specific to the population is essential. The aim of the current research was to develop and validate a specific ACJ questionnaire. METHODS: Items for the "Specific AC Score" (SACS) were generated through the use of an expert panel, existing questionnaires, and patient feedback. Preliminary data analysis identified redundancy of items resulting in the questionnaire being refined. The final SACS was evaluated in 125 patients requiring surgical intervention of the ACJ. Internal consistency (the Cronbach α and corrected item-total correlation), content validity, criterion validity, responsiveness, and test-retest reliability (intraclass correlation coefficient) were examined and compared with the Shoulder Pain and Disability Index, Oxford Shoulder Score, and American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form. The minimum detectable change score was calculated. RESULTS: The Cronbach α for the total scale preoperatively and postoperatively was high (preoperatively = 0.91, postoperatively = 0.93). All 3 domains (Pain, Function, Quality of Life) demonstrated acceptable internal consistency (α > 0.70), and the correlation between items in each domain was satisfactory. The responsiveness was excellent (effect size, -2.32; standard response mean, -1.85) and was higher than the other general shoulder questionnaires. There were no relevant floor or ceiling effects. Reliability was high (intraclass correlation coefficient, 0.89) and the minimum detectable change was 6.5 points. DISCUSSION: This new ACJ-specific questionnaire has been robustly developed, has good measurement properties, and has excellent responsiveness. The SACS is recommended for measuring outcomes in ACJ patients.

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.

Operative shoulder instability injury management in Australian Football League players: A case series.

OBJECTIVES: The purpose of this study was to review the surgical management procedures of shoulder instability injuries in Australian Football League (AFL) players, and determine outcomes regarding return to sport and injury recurrence. DESIGN: Retrospective cohort study. METHODS: Elite AFL players with shoulder instability resulting in surgery were assessed in a retrospective cohort design (72 players/77 shoulders). Type of initial injury, surgical management, return to sport and injury recurrence were obtained. The mean follow-up period post-surgery was 2.9 years. Return to sport outcomes were compared between arthroscopic and open surgery using a Kaplan-Meier survival analysis. Logistic regression modelling was used to determine associations between injury recurrence, type of injury, participant age and method of surgery. RESULTS: Shoulder instability injuries occurred most frequently during tackling (40%). Arthroscopic surgery was preferred for primary shoulder instability. Nine (16%) recurrences occurred in those who underwent arthroscopic surgery compared to two (9%) following open surgery. Return to the elite level was slightly but significantly (2 weeks, p=0.049) longer for open compared to arthroscopic surgery. Recurrence was 5 times more likely if the primary injury was a dislocation and more likely in players who were younger at the time of surgery. CONCLUSION: Tackling was the predominant mechanism for shoulder instability injuries in AFL players and arthroscopic surgery was more commonly performed for primary injuries. Sustaining a dislocation as the primary injury and younger age increased the likelihood of recurrent instability. Careful consideration should be given to the operative management of these individuals.

A comprehensive rehabilitation program for posterior instability of the shoulder.

Posterior shoulder instability is recognised as being less prevalent than anterior instability, however the diagnosis of this pathology is easily overlooked or missed and this may contribute to an underestimation of prevalence. Recently, there has been increasing recognition of this condition and consequently a greater requirement for knowledge of diagnostic procedures and treatment directions. Currently there is limited research into the conservative management of posterior instability, although it is recommended as first-line treatment prior to surgical review, particularly in those with an atraumatic instability mechanism. The aim of this paper is to outline a comprehensive rehabilitation program for the conservative management of posterior instability with a focus on scapular and humeral head control. The information provided includes extensive written information, flowcharts, figures and a table of management parameters that will provide therapists with adequate detail to replicate the program in the clinical setting.

Orthotic intervention incorporating the dart-thrower's motion as part of conservative management guidelines for treatment of scapholunate injury.

STUDY DESIGN: Case series. INTRODUCTION: This paper describes conservative guidelines for the management of scapho-lunate interosseous ligament (SLIL) injury including fabrication of an orthosis that restricts active wrist movement to the dart-throwers (DTM) plane. PURPOSE OF THE STUDY: The dart throwers' orthosis (DTO) was designed as a response to biomechanical studies suggesting that restraining motion to the DTM would off-load a deficient SLIL. METHODS: After six weeks of wearing the DTO, the 5 patients in this case series initiated an exercise program that incorporated wrist proprioceptive training and specific muscle strengthening. DISCUSSION: The DTO was designed to incorporate controlled movement in order to better integrate the secondary wrist stabilizers in wrists that had a deficient SLIL. The orthosis and the exercise program harnessed proprioceptive influences using active motion within the DTM plane, and stimulated mechanoreceptors so as to enhance stability. RESULTS: All patients demonstrated improvement in subjective and objective outcomes including self-reported pain and function. CONCLUSIONS: Orthotic intervention that controls motion within the DTM, combined with an appropriate proprioceptive rehabilitation program, may provide a viable conservative treatment option for patients with a similar clinical presentation. LEVEL OF EVIDENCE: 4.

MRI of stress reaction of the distal humerus in elite tennis players.

OBJECTIVE: The purpose of this study was to describe the MRI appearance of stress reaction in the distal humerus in 12 elite tennis players. In addition, we aimed to determine whether any MRI findings were associated with changes in recovery times. CONCLUSION: Stress injury to the distal humerus is a cause of chronic arm pain among elite tennis players and may be exacerbated during full competition. The degree of marrow edema on STIR MRI may be predictive of time to return to competition.

A new clinical outcome measure of glenohumeral joint instability: the MISS questionnaire.

Many standard shoulder outcome measures do not adequately cover the range of problems and issues specifically encountered in glenohumeral joint instability and have been shown not to be sensitive enough to detect clinical change with intervention adequately. The purpose of this report is to present a prospective evaluation of a new self-administered patient questionnaire specifically designed to assess glenohumeral joint instability. The evaluation involved test-retest reliability and comparison with the Shoulder Rating Questionnaire (SRQ). Sixty-four patients with confirmed glenohumeral joint instability were assessed with both the Melbourne Instability Shoulder Scale (MISS) and SRQ 12 preoperatively and at 6 months after shoulder reconstructive surgery. Twenty-two patients were recruited into a reliability study of the MISS questionnaire. The test-retest reliability of the MISS was found to be 0.98 (interclass correlation coefficient, mixed-model analysis of variance, absolute agreement). Assessment of agreement between the MISS and SRQ questionnaires indicated very poor pretest agreement (0.33) and moderate agreement at 6 months (0.66). The differences between the MISS and SRQ were statistically significant both before surgery (paired t = 13.2, degrees of freedom [ df ] = 63, P < .001) and at 6 months' follow-up (paired t = 7.9, df = 63, P = .001). Change in the questionnaire scores measured from surgery to 6 months' follow-up was significantly greater in the MISS (mean, 30; SD, 19.1; median, 30.8) than in the SRQ (mean, 16.6; SD, 12.8; median, 14.3) (Wilcoxon test: z = -5.8, P = .0001). The results of this study show that the MISS questionnaire is a reliable outcome questionnaire and has a greater range to detect changes in shoulder instability than more global outcome questionnaires such as the SRQ. The higher scores encountered on the SRQ may mean that it underestimates the severity of a patient's instability problem.