Comparison of intra-articular and subacromial corticosteroid injection in frozen shoulder: A meta-analysis of randomized controlled trials

Objective: To compare the efficacy and safety of intra-articular injection and subacromial injection in the treatment of primary frozen shoulder (FS).

Methods: We conducted a systematic literature search for all relevant studies on Medline, Embase, Web of Science and Cochrane Central, up to April 2019 with no restrictions to language of publication. The primary outcome was visual analog scale (VAS) score, range of motion (ROM), and Constant shoulder score. The secondary outcome was injection-related adverse effects. Two authors independently assessed the risk of bias using the Cochrane risk-of-bias tool. Data were conducted using STATA version 12.0 (STATA corp., College Station, TX).

Results: Seven randomized controlled trials (RCTs) involving 421 participants were finally included in the present meta-analysis. Our study indicated that intra-articular injection was associated with a statistically significant reduction in the outcome of pain score compared with the subacromial injection. No significant differences were identified between two groups regarding the ROM or post-injection adverse events.

Conclusion: Intra-articular injection of corticosteroid was associated with an improved outcomes for pain relief compared to subacromial injection. There was no significant difference regarding the shoulder function or adverse effects.