IntroductionThe purpose of this study was to evaluate the clinical and radiological results of complex lateral tibial plateau fractures involving the central segments of the lateral tibial plateau. It was hypothesized that an extended lateral approach by using the lateral epicondyle osteotomy improves the rate of malreduction and yields to good and excellent clinical results at a mid-term follow-up. MethodsThis retrospective case series conducted at two centers evaluated complex lateral tibial plateau fractures treated with an extended lateral approach by lateral epicondyle osteotomy. Fractures were classified according to the AO/OTA and 10-segment classification, with only B/C type fractures involving the antero-latero-central (ALC) and postero-latero-central (PLC)/postero-latero-lateral (PLL) segments. Postoperative computer tomography scans were used to assess the quality of reduction. Clinical outcomes and postoperative complications were evaluated with a minimum follow-up of 2 years. ResultsSixty-five patients (mean age: 47.7 ± 11.5 years) were included, with an average follow-up of 51.9 ± 3.6 months. Radiological outcomes revealed a postoperative fracture step at the ALC/PLC crossing of 0.8 ± 1.1 mm, at the PLC/PLL crossing of 0.4 ± 1.1 mm, and a fracture gap of 1.8 ± 4.0 mm, yielding a Rasmussen Score of 15.1 ± 3.2. No significant differences among type B and C fractures were identified. No case of nonunion of the lateral epicondyle osteotomy was recorded. The mean Knee injury and Osteoarthritis Outcome Score was 80.4 ± 16.2 (type B 85.6 ± 11.9 vs. type C 76.1 ± 18.4, p < 0.05), Lysholm score was 83.4 ± 17.1 (B 89 ± 11.3 vs. C 78.7 ± 20.1, p < 0.05) and International Knee Documentation Committee score was 69.9 ± 18.8 (type B 76.5 ± 15.7 vs. type C 64.3 ± 20.1, p < 0.05). Early complication rate requiring surgical revision due to malreduction or infection were 7 %. None of the patients reported about subjective lateral knee instability at the time of clinical follow-up. ConclusionThe extended lateral approach with lateral epicondyle osteotomy demonstrated excellent radiological alignment and favorable mid-term clinical outcomes. An overall low complication rate was recorded. Notably, long-term revisions due to lateral instability were absent, indicating the safety and efficacy of lateral epicondyle osteotomy as an operative technique.