Posterolateral vs. anterolateral approach for posterolateral tibial plateau fractures: A multicenter cohort with four-year outcomes.

Abstract

Posterolateral tibial plateau fractures (PLTPFs) are challenging due to limited surgical access. The posterolateral approach (PLA) offers direct visualization, while the anterolateral approach (ALA) is more familiar but may compromise reduction quality. This multicenter cohort study compares PLA versus ALA for PLTPFs with four-year follow-up. A multicenter concurrent cohort study (January 2020 - December 2024) included 110 patients with PLTPFs confirmed on CT. Fifty-five underwent ORIF via PLA, and 55 via ALA. Primary outcome was articular step-off on postoperative CT (two blinded radiologists, ICC=0.92). Secondary outcomes included range of motion, IKDC score, Tegner-Lysholm score, complications, revision surgery. Multivariable logistic regression and Kaplan-Meier survival analysis were performed. Mean articular step-off was 0.9±0.5 mm in the PLA group versus 1.8±0.8 mm in the ALA group (mean difference 0.9 mm, 95% CI: 0.6-1.2, p < 0.001). Anatomic reduction (<2 mm) was achieved in 89.1% (49/55) of PLA patients versus 70.9% (39/55) of ALA patients (p = 0.02; adjusted OR=3.8, 95% CI: 1.4-10.2, p = 0.008). At four years (n = 98, 89.1% retention), mean IKDC score was 86.7±6.2 versus 79.3±7.5 (p < 0.001), and 78% of PLA patients achieved MCID versus 52% of ALA patients (p = 0.01). Transient peroneal neurapraxia occurred in 7.3% (4/55) of PLA versus 1.8% (1/55) of ALA (p = 0.18), all resolving within 6 months. In fractures with associated fibular head or neck fracture, the common peroneal nerve may be under tension; fibular fixation or nerve release should be considered. Revision surgery was 3.6% (2/55) in PLA versus 10.9% (6/55) in ALA (p = 0.14). Kaplan-Meier analysis showed a trend toward better implant survivorship in the PLA group (96.4% vs. 89.1% at 4 years, log-rank p = 0.048). In this multicenter cohort with four-year follow-up, the posterolateral approach for PLTPFs provided better reduction quality, and superior functional outcomes compared to the anterolateral approach, with an acceptable rate of transient peroneal neurapraxia.