Early Versus Delayed Mobilization Post-Operative Protocols for Primary Lateral Ankle Ligament Reconstruction: A Systematic Review and Meta-Analysis.

Introduction: Lateral ankle instability represents a common orthopaedic diagnosis. Nonoperative treatment through focused physical therapy provides satisfactory results in most patients. However, some patients experience persistent chronic lateral ankle instability despite appropriate nonoperative treatment. These patients may require stabilization, which can include primary lateral ligament reconstruction with a graft to restore ankle stability. Optimal post-operative rehabilitation of lateral ankle ligament reconstruction remains unknown, as surgeons vary in how long they immobilize their patients post-operatively. The aim of this review was to provide insight into early mobilization (EM) versus delayed mobilization (DM) post-operative protocols in patients undergoing primary lateral ankle ligament reconstructions to determine if an optimal evidence-based post-operative rehabilitation protocol exists in the literature.

Methods: Following PRIMSA criteria, a systematic review/meta-analysis using the PubMed/Ovid Medline database was performed (10/11/1947 - 1/28/2020). Manuscripts that were duplicates, non-lateral ligament repair, biomechanical, and non-English language were excluded. Protocols were reviewed and divided into two categories: early mobilization (within three weeks of surgery) and delayed mobilization (after three weeks of surgery). Functional outcome scores (American Orthopedic Foot and Ankle Society Score (AOFAS), Karlsson scores), radiographic measurements (anterior drawer, talar tilt), and complications were evaluated using weighted mean differences (pre- and post-operative scores) and mixed-effect models.

Results: After our search, twelve out of 1,574 studies met the criteria for the final analysis, representing 399 patients undergoing lateral ankle reconstruction. Using weighted mean differences the DM group showed superior AOFAS functional scores compared to the EM group (28.0 (5.5) vs. 26.3 (0.0), respectively; p < 0.001), although sample size was small. Conversely, no significant differences were found for Karlsson functional score (p = 0.246). With regards to radiographic outcome, no significant differences were observed; anterior drawer was p = 0.244 and talar tilt was p = 0.937. A meta-analysis using mixed-effects models confirmed these results, although heterogeneity was high.

Conclusions: While there are some conflicting results, the findings indicated the timing of post-operative mobilization made no difference in functional outcomes or post-operative stability for patients undergoing lateral ankle ligament reconstruction. Because heterogeneity was high, future studies are needed to evaluate these protocols in less diverse patient groups and/or more consistent techniques for lateral ankle ligament reconstruction.