Extra-articular Osteotomy for the Management of Intra-articular Tibial Plateau Valgus Malunion

OBJECTIVES: To report a case series of extra-articular osteotomies for the management of intra-articular tibial plateau malunions and to assess the ability to correct deformity and improve knee range of motion (ROM). METHODS: Design: Retrospective case series Setting: Academic, tertiary, referral center. Patient Selection Criteria: Adult patients with tibial plateau fracture malunion treated with extra-articular osteotomy of the femur and/or tibia between 2014-2023. Outcome Measures and Comparison: Mechanical axis deviation (MAD), medial proximal tibia angle (MPTA), lateral distal femoral angle (LDFA), and posterior proximal tibia angle (PPTA) correction; knee ROM, and time to weight bearing. RESULTS: There were 7 patients included, 6 (85.7%) were female and 1 (14.3%) were male. The median age was 43.5 years (IQR 38.5-51, range 32-62). Four (57.1%) patients were treated with a high tibial osteotomy (HTO) and 3 (42.9%) patients were treated with an HTO and distal femoral osteotomy (DFO). One patient had concomitant supramalleolar osteotomy with HTO to address distal tibia procurvatum and valgus. Four were treated with hexapod frames and 3 were treated with plates and screws. Median follow-up was 22.5 months (IQR 10.5-107 months, range 7-148 months). Surgical intervention corrected median radiographic measures of valgus malalignment pre-operatively relative to post-operative values. This included MAD (42.5mm to 0mm), valgus angle (12.5° to 1.5°), MPTA (95° to 88.0°), and LDFA 86.0° to 87.3°). Surgical intervention increased maximal knee range of motion pre- to post-operatively. Median time to full weight bearing was 81.5 days (IQR 46-57 days, range 41-184 days Two patients were converted to total knee arthroplasty after 5 and 10 years following HTO with hexapod frame. CONCLUSIONS: Extra-articular osteotomy is an effective treatment for addressing intra-articular malunion after tibia plateau fractures. It is effective in correcting the MAD, valgus deformity, MPTA, LDFA, PPTA, and improving knee ROM (measured through knee extension and flexion). LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.