Anterior shoulder dislocations are among the most common shoulder injuries in adolescent athletes and often occur after acute trauma. Despite multiple studies comparing rates of recurrent instability after surgical stabilisation and non-operative sling immobilisation for patients experiencing a first-time anterior shoulder dislocation, there remains uncertainty about the best treatment approach.
This systematic review aimed to estimate the effects of surgical stabilisation for people with a first-time anterior shoulder dislocation on recurrent instability, need for a future stabilisation procedure, range of motion, and function compared to sling immobilisation.
Searches were performed in seven databases (including PubMed, Embase, and Cochrane Library) to identify randomised controlled trials investigating the effects of surgical stabilisation versus sling immobilisation for the treatment of first-time anterior shoulder dislocation on rates of recurrent instability.
The outcomes were recurrent instability, subsequent stabilisation surgery, range of motion, function as assessed by the Western Ontario Shoulder Instability Index, and complications. Only outcomes reported by at least three trials were included. Two independent reviewers selected trials for inclusion. Disagreements were resolved by discussion or by arbitration from a third reviewer. Data were extracted by one reviewer and checked by a second. Trial quality was evaluated using version 1.0 of the Cochrane risk of bias tool. Meta-analysis was used to pool trials and calculate the between-group risk ratio, and the associated 95% confidence interval (CI), for recurrent instability and subsequent stabilisation surgery.
Five trials (259 participants) were included in the review. The average age of participants and percentage of males was 24 years and 87% in the operative group, and 23 years and 89% in the non-operative group. Four trials used similar arthroscopic Bankart procedures, and one used an open Bankart procedure. Participants in all trials underwent surgery between 10 and 28 days after anterior shoulder dislocation and were placed in an internally rotated sling immobiliser for 1-4 weeks post-operatively. The non-operative approach in 4 trials involved placing participants in an internal rotation sling for 1-4 weeks. In 1 trial, participants were placed in an external rotation and abduction immobiliser for 3 weeks. Physiotherapy protocols were identical between the operative and non-operative groups across trials and involved minimal active or passive movement through the immobilisation phase (about 3 weeks), active external rotation and abduction until 6 weeks, unrestricted range of motion after 6-12 weeks, and resistance exercises thereafter. All trials were at high risk of bias due to being unable to blind participants (performance bias) and therapists and/or outcome assessors (detection bias).
Surgical stabilisation reduced the risk of recurrent instability by 83% (95% CI 67% to 92%) and the risk of subsequent stabilisation surgery by 83% (95% CI 59% to 93%) compared to sling immobilisation. Findings were the same when only including trials in which participants in the non-operative group were immobilised in internal rotation. All 3 trials that assessed range of motion found no difference between surgical stabilisation and sling immobilisation. Of the 3 trials that assessed Western Ontario Shoulder Instability Index scores, 1 found higher scores in the operative group and 2 found no difference. Two complications were reported in the operative group and none in the non-operative group.
Surgical stabilisation for a first-time anterior shoulder dislocation reduces the risk of recurrent instability and need for a future stabilisation procedure compared to non-operative management involving sling immobilisation. It is uncertain whether surgical stabilisation is superior to non-operative management for improving shoulder function and range of motion.
Belk JW, et al. Shoulder stabilization versus immobilization for first-time anterior shoulder dislocation: a systematic review and meta-analysis of level 1 randomized controlled trials. Am J Sports Med 2022 Feb 11:Epub ahead of print.