Clinical and functional outcomes of subacromial spacer implantation and superior capsular reconstruction for massive irreparable rotator cuff tears: a systematic review and meta-analysis.

BACKGROUND: Various surgical techniques are available for treating Massive and Irreparable Rotator Cuff Tears (MIRCTs). However, there is no agreement on which approach is the most effective. We have conducted a systematic review and analyzed the clinical outcomes of two advanced procedures: Subacromial Spacer Implantation (SSI) and Arthroscopic Superior Capsular Reconstruction (ASCR) for managing MIRCTs. METHODS: A comprehensive search using MeSH and keywords was performed on Medline/ PubMed, Embase, Web of Science, Scopus, and Cochrane Database up to August 2023 for observational and pre-post clinical trials regarding the study outcomes. American Shoulder and Elbow Score (ASES), Constant score (CS), Visual Analogue Scale (VAS), University of California-Los Angeles (UCLA), Simple Shoulder Test (SST), Subjective Shoulder Value (SSV), Japanese Orthopaedic Association (JOA), and Range of Motion (ROM) were considered as clinical and functional outcomes. The retrieved studies were assessed for methodological quality. Random-effects meta-analysis was used to estimate the pooled Weighted Mean Difference (WMD) with a 95% confidence interval (CI), considering the clinical and methodological heterogeneity across studies. We also performed subgroup meta-analysis and sensitivity analysis. RESULTS: Findings of the meta-analysis on 35 pre-post clinical trials, mainly fair to good quality, showed that clinical scores significantly improve after ASCR, ASES (WMD: 40.76; 95% CI: 35.9 to 45.6), CS (WMD: 33.34; 95% CI: 24.2 to 42.3), and VAS (WMD: -4.30; 95% CI: -4.8 to -3.7). The ROM reached 45.83 (95% CI: 33.6 to 58) for abduction, 42.8 (95% CI: 28.6 to 56.9) for flexion, 0.13 (95% CI: -1.5 to 1.8) for internal rotation, and 11.5 (95% CI: 7.5 to 15.4) for external rotation after surgery. The acromiohumeral distance (AHD) increased by 2.69 mm (95% CI: 1.9 to 3.4 mm). We found no publication bias, and the meta-analysis findings were robust in sensitivity analysis. CONCLUSIONS: Two advanced procedures, SSI and ASCR, for patients with MIRCTs showed significantly improved clinical and functional outcomes. It is difficult to directly compare the effectiveness of these two procedures. More long-term, large-scale, and high-quality trials are needed to confirm their effectiveness.