Repair Fails More Frequently Than Reconstruction in Acute Posterolateral Corner Knee Injuries: A Systematic Review of Outcomes Following Surgical Management

Purpose: To synthesize the current literature on PLC reconstruction and repair, focusing on a comparison of surgical techniques and outcomes based on injury chronicity in the setting of sports-related ligament tears.

Methods: A systematic review of the literature including queries of the PubMed/MEDLINE, Embase, and Cochrane Library databases was performed in March of 2024. Studies were included if they were of level IV evidence or greater, reported PLC reconstruction or repair outcomes, and had a minimum 2-year follow-up. Patient demographics, injury type, time from injury to surgery, surgical technique, subjective patient outcomes, objective physical exam findings, and complications were obtained. Postoperative physical exam findings of varus and posterolateral rotatory stability and reoperation for instability were used to determine surgical success or failure. Means and ranges were recorded for continuous variables. Forest plots were generated for failure rates by subgroup and an I-squared statistic was used as a measure of heterogeneity. Except for 3 studies, injuries were considered acute when treated within 3 weeks of injury. Quality assessment was conducted using the Newcastle-Ottawa Scale (NOS) for cohort studies and the National Institute of Health (NIH) Quality Assessment Tool for case series studies.

Results: Twenty-nine of the sixty-three reviewed studies (791 patients) met inclusion criteria. Two of the studies were level II, eleven level III, and sixteen level IV evidence. Mean patient age ranged from 19 to 69.1 years. Mean time from injury to surgery ranged from 8.1 to 19 days (acute) and 7.2 weeks to 70.2 months (chronic). Mean postoperative Lysholm scores ranged from 80.8 to 97.0 (acute) and 76.5 to 94.5 (chronic). Mean postoperative IKDC scores ranged from 59.8 to 87.3 (acute) and 64 to 91.9 (chronic). Within the acute PLC group, 114 (59.3%) patients were treated with isolated repair and the remaining 78 (40.7%) were treated with reconstruction. Within this group, failure rates, defined by varus stress examination or reoperation, ranged from 0 to 40%. More specifically , reconstruction failure rates ranged from 0 to 15%, whereas repair failure rates ranged from 0 to 40%. All 602 chronic PLC patients were treated with reconstruction and the failure rate ranged from 0 to 27%, with a single outlier study of two patients reporting a 50% failure rate.

Conclusion: The findings of this review suggest that repair of PLC injuries in the acute setting may fail at higher rates than reconstruction. Additionally, chronic PLC injuries are predominantly treated with reconstruction and experience greater variability in their rates of success compared to acute injuries. High-quality, well-controlled studies are needed to determine optimal management of both acute and chronic PLC injuries.