Similar outcomes between arthroscopic capsular release and manipulation under anaesthesia for frozen shoulder: A meta-analysis.

To compared the arthroscopic capsular release (ACR) with manipulation under anaesthesia (MUA) for the surgical treatment of frozen shoulder (FS) based on postoperative outcomes and complications. PubMed, Cochrane Library, Embase, and Web of Science were searched on October 2, 2023 to retrieve eligible studies that compared ACR with MUA in terms of clinical outcomes (pain visual analogue scale, external rotation, forward flexion and adverse events) for patients with FS. Mean differences (MD) were calculated for continuous outcomes and odds ratios (OR) were calculated for dichotomous outcomes. Six papers, including 5 clinical studies (a total of 690 shoulders), were included in the final meta-analysis. The forward flexion was found to be larger in the ACR group at 3 months (MD, 2.73; 95%CI, 0.42-5.04; I2  = 44%; P = 0.02) and 6 months (MD, 2.36; 95%CI, 1.29-3.44; I2  = 0%; P < 0.0001). Except for this, ACR was comparable with MUA in terms of pain visual analogue scale at 3, 6 and 12 months (p = 0.25, p = 0.11, p = 0.28, respectively), external rotation at 3, 6 and 12 months (p = 0.15, p = 0.52, p = 0.23, respectively), and forward flexion at 12 months (p = 0.08). There were no differences in complication rates between the two groups (OR, 0.82; 95%CI, 0.47-1.44; I2  = 0%; P = 0.50). In comparison with MUA, ACR demonstrated better outcomes for forward flexion at 3 and 6 months, while there were no significant differences between ACR and MUA in terms of pain visual analogue scale, external rotation and adverse events.