Management of anterior shoulder instability in patients aged 40 or above: a systematic review
Background: Anterior shoulder instability (ASI) is a common shoulder condition, with considerable research focused on outcomes and surgical interventions in younger adults. Existing literature suggests that treatment planning for older adults with ASI may require unique considerations due to differences in underlying pathology and injury complication rates. Objective: The purpose of this review was to systematically evaluate and synthesize the literature on ASI in patients with first-time dislocations at 40 years or older regarding injury characterization, treatment modalities, and clinical outcomes. Methods: Three databases (PubMed, MEDLINE, Embase) were searched. Primary studies were included if they investigated operative or non-operative management of ASI in patients with first-time dislocation at 40 years or older. Studies were quality-assessed using the MINORS criteria. Data was extracted and compiled in a spreadsheet designed a priori. Descriptive statistics were used to evaluate results. Results: Ten primary studies were included with 541 patients (541 shoulders), of which 315 were managed non-operatively and 226 were managed operatively. Seven studies included only patients with primary traumatic ASI, whereas three studies included patients with recurrent ASI. The most common operative procedures were rotator cuff repair (n=182), Bankart repair (n=29), and reverse shoulder arthroplasty (n=10). The rate of post-operative recurrent instability was 8.2%. The most common concomitant injuries included rotator cuff tears (53.5%), Hills-Sachs lesions (46.7%), and glenoid bone defects (8.0%). Reported range of motion and patient-reported outcome measures varied across interventions, but significant positive outcomes were demonstrated in both non-operative and operative cohorts. Conclusions: ASI in older adults is frequently associated with concomitant injuries which may be more amenable to surgical management, often leading to favourable outcomes. Future prospective, comparative studies using standardized outcome measures are needed to better define optimal management strategies in this age group.