Shoulder Instability: Arthroscopic Capsulolabral Repair: the Gold Standard

Shoulder instability in military personnel: diagnosis and outcomes of arthroscopic stabilisation

INTRODUCTION

Shoulder instability is a common problem for military personnel due to the highly physical demands of work and training. This study assessed the pattern of glenoid labrum tears suffered by serving UK military personnel, the reliability of preoperative diagnostic methods (magnetic resonance arthrogram (MRA) vs clinical examination) and, finally, the outcomes of arthroscopic stabilisation in terms of satisfaction, pain, and return to sport and full deployment.

METHODS

Retrospective demographic and clinical data were collected for all patients within our unit who underwent arthroscopic shoulder stabilisation between September 2016 and January 2019. Patients underwent clinical examination for instability and subsequent imaging with MRA. For service evaluation, patient-reported outcome measure data and occupational outcome data were gathered preoperatively and postoperatively.

RESULTS

41 military patients with shoulder instability were treated with arthroscopic stabilisation. 24.4% had an isolated anterior tear, and 41.5% had complex two-zone or pan-labral tears identified on arthroscopy. Clinical examination showed higher sensitivity, accuracy and negative predictive value for all labral tear patterns compared with MRA. Mean preoperative Oxford Shoulder Instability Score score was 18.58 (SE ±1.67) and mean postoperative score was 41.5 (SE ±1.13). 82.14% of the patients returned to full deployment during the study period and 85% had returned to sports.

CONCLUSION

Complex labral tear patterns are common in military personnel with shoulder instability, and clinical examination appears to be more effective than imaging at predicting injury pattern. Patients respond well to arthroscopic stabilisation with good rates of return to work and sport, regardless of chronicity of injury.

Biomechanical Strength of Screw Versus Suture Button Fixation in the Latarjet Procedure: A Cadaver Study

We compared the strength of screw vs suture button fixation in the Latarjet procedure for shoulder dislocation through biomechanical testing in a cadaver model. Cadavers were assigned randomly to receive screw or suture button fixation (both groups, n=5). The anteroposterior radius of the glenoid was measured, and a bony defect was created on the anteroinferior rim of the glenoid, equal to 25% of the width of the anteroposterior radius of the glenoid surface. The coracoid process was transferred into the newly created bony defect of the glenoid and fixed with two 3.5-mm partially threaded cannulated screws or 2 surgical buttons. All samples underwent tensile testing in the anteroinferior direction. Statistical analysis was performed to compare mean forces at failure between groups (alpha=.05). The mean force at failure was higher in the screw group (295 N; range, 103-534 N) than in the suture button group (133 N; range, 74-270 N) (P=.045). We found no difference between groups in ability to withstand a force of 150 N, which is the reported mean daily force threshold borne by the shoulder (P=.52). Screw fixation withstood a higher failure load than suture button fixation, indicating that screw fixation is a biomechanically superior option in the Latarjet procedure. The fixation methods did not differ in their ability to withstand the mean force borne by the shoulder during activities of daily living; thus, suture button fixation should be considered as an option in the Latarjet procedure. [Orthopedics. 2022;45(6):e321-e325.].