MUCL Reconstruction using Internal Bracing: A Meta-Analysis of Biomechanical Studies

The purpose of this systematic review and meta-analysis was to evaluate human biomechanical studies investigating ulnar collateral ligament (UCL) reconstructions using an internal brace mechanical augment construct. A search following PRISMA guidelines was performed in August 2025 across PubMed, Cochrane, and Web of Science databases to identify studies reporting biomechanical outcomes of UCL reconstructions in isolation compared to UCL reconstruction with an internal brace. A total of 329 studies were reviewed, with 6 meeting inclusion criteria. Data on ultimate failure torque (Nm), stiffness (Nm/deg), ulnohumeral gapping (mm), and valgus laxity (deg) were extracted. A meta-analysis comparing these four biomechanical parameters was conducted using a systematic review, a random-effects model, and pooled standardized mean differences (SMD). For ultimate failure torque, the pooled SMD was 1.54 ([-0.28 to 3.35], p = 0.074), trending towards higher torque strength for internal brace. For graft stiffness, the pooled SMD was 0.91 ([-0.17 to 1.99], p = 0.068), trending towards higher stiffness for the internal brace constructs. For ulnohumeral gapping, the pooled SMD was -0.52 ([-1.01 to -0.03], p = 0.043), indicating a statistically significant effect of less gapping for the internal brace. Internal brace augmentation resulted in decreased ulnohumeral gapping and demonstrated favorable biomechanical trends compared with traditional UCL reconstruction, suggesting improved early construct stability.