Approach to shoulder instability: a randomized, controlled trial

The significant rate of recurrent instability following arthroscopic stabilization surgery points to a need for an evidence-based treatment approach. The instability severity index Score (ISI score) is a point-based algorithm that may be used to assist clinicians in selecting the optimal treatment approach, but its efficacy compared with a traditional treatment algorithm has not been previously validated. The aim was to compare two surgical treatment algorithms: the ISI score and a conventional treatment algorithm (CTA).

This was a prospective, randomized controlled trial involving participants who were randomized to either the ISI score or CTA and were followed for 24 months postrandomization. In the ISI score cohort, patients underwent a Latarjet procedure if they presented with a score >3 points. Those scoring ISI score ≦3 points underwent an arthroscopic Bankart repair. Patients randomized to the CTA group underwent a Latarjet procedure if the glenoid bone loss was > 25%. The primary outcome was the Western Ontario Shoulder Instability Index. Secondary outcomes included the American Shoulder and Elbow Surgeons score as well as recurrence rates between groups.

Sixty-three patients were randomized to ISI score (n = 31) or CTA (n = 32). At two years, the Western Ontario Shoulder Instability Index score was similar between groups (ISI score: 84.1 ± 16.9, CTA: 85.7 ± 12.5, P = .70). Similarly, no differences were detected in American Shoulder and Elbow Surgeons scores (ISI score: 93.2 ± 16.2, CTA: 92.6 ± 9.9, P = .89). Apprehension was reported in 18.5% for the ISI score group and 20% in the CTA group (P = 1.00). At a 24-month follow-up, there was no difference in redislocations: one in ISI score group and none in the CTA group (P = .48). There were two revision surgeries in the ISI score group and two in the CTA group.

This study did not demonstrate any differences in functional outcomes, the incidence of apprehension, or failure rates between the two treatment algorithms at 24-month follow-up.