Efficacy and safety of xenograft augmentation in rotator cuff repair: a systematic review and meta-analysis

Rotator cuff tears are common disorders that can significantly impact patientś shoulder function and quality of life. Incomplete or failed healing is relatively common following repair of large tendon tears. Xenograft materials are increasingly used for augmentation of repairs, but their efficacy and safety remain under debate. This systematic review and meta-analysis aimed to evaluate the outcomes of xenograft-augmented rotator cuff repair in comparison to standard repair techniques. A detailed literature search was conducted across PubMed, Embase, Cochrane Library, and Web of Science databases on September 2, 2023, focusing on studies that utilized xenograft materials in rotator cuff repair. We included randomized controlled trials (RCTs) and cohort studies (CHS) that reported on dichotomous and continuous outcome measures. Risk of bias was assessed using the Cochrane Risk of Bias tool 2 (RoB2) for RCTs and the Risk of Bias assessment for non-RCT studies-I tool for nonrandomized studies. Data synthesis was performed using random-effects models to compute odds ratios (ORs) and standardized mean differences. Eight studies met the inclusion criteria, including three RCTs and five CHS evaluating xenograft materials, including porcine dermis and small intestine submucosa patches. Meta-analysis of RCT data revealed no statistically significant difference in failure rates between xenograft-augmented and standard repair groups (OR 0.48, 95% CI 0.08-2.90; P = .42), as did CHS (OR 1.08, 95% CI 0.49-2.38; P = .85). Similarly, the radiological healing rates showed no significant benefit for xenograft use (OR 1.41, 95% CI 0.23-8.56; P = .71). However, xenograft use was associated with a statistically significant higher complication rate (OR 3.65, 95% CI 1.28-10.4; P = .02). No significant differences were observed in strength measurements and range of motion. Xenograft-augmented repair of rotator cuff tears does not significantly improve radiological healing nor reduce failure rates compared to standard repair. However, it is associated with a higher complication rate. These findings suggest that while xenograft materials may be safe for clinical use, their benefits over traditional repair techniques are not conclusively supported by current evidence. Further high-quality, multicenter RCTs are needed to confirm these results and to explore alternative xenograft implants as well as the role of patient-intrinsic factors, such as tear size, tendon and muscle quality, and medical comorbidities on outcome.