Arthroscopic capsular release to treat idiopathic frozen shoulder: How much release is needed?

Abstract

Purpose: This systematic review and meta-analysis aims to provide consensus regarding the degree of optimal extended arthroscopic capsular release in addition to a standard rotator interval release in the treatment of idiopathic frozen shoulder.

Materials and methods: The systematic review was conducted using the Preferred Reporting Items for Systemic Reviews and Meta-Analyses (PRISMA) guidelines. All articles that reported the outcomes of capsular release in idiopathic frozen shoulder were included. A total of 18 articles with 629 patients and 811 shoulders were included. Clinical outcomes analysed include differences between pre and postoperative ranges of motion (ROM), Visual Analog Score (VAS) reduction, Simple Shoulder Test (SST) scores and Constant scores. Patients were grouped by technique: anterior-inferior capsular release (Group 1), anterior-inferior-posterior capsular release (Group 2), and 360-degree capsular release (Group 3) at follow up points 3,6 and 12 months.

Results: Comparing ROM, Group 1 had greater early abduction (p<0.01), early (p<0.01) and overall external rotation (p<0.01) than Group 2, as well as greater early flexion (p<0.01), early abduction (p<0.01), early (p<0.01) and overall internal rotation (p<0.01) than Group 3. Group 2 had greater early (p=0.03) and overall flexion (p<0.01) than Group 1, as well as greater early (p<0.01) and overall flexion (p<0.01), early abduction (p<0.01) and early internal rotation (p<0.01) than Group 3. Group 3 had greater overall flexion (p<0.01) than Group 1 and greater overall external rotation (p<0.01) than Group 2. Comparing VAS scores, the less extensive releases saw the greatest significant postoperative reduction. Group 2 had greater mean improvements in postoperative Constant scores than Group 1 (p<0.01) and Group 3 (p<0.01), while SST scores were significantly higher in Group 1 (p<0.01).

Conclusion: This systematic review and meta-analysis suggests that less extensive releases may result in better functional and pain scores. Addition of a posterior release offers increased early internal rotation, which was not sustained over time, but provides early and sustained flexion improvements. A complete 360 release may not provide any further benefit. There were no significant differences in the complication rates amongst the 3 techniques.

Level of study: II; Meta-analysis and systematic review.

Keywords: Adhesive capsulitis; Arthroscopic; Capsular release; Complications; Extended; Frozen shoulder.