Mid-term outcomes of posterior malleolar fracture plating: identifying predictors of adverse outcomes
摘要
While surgical fixation of posterior malleolar fractures (PMFs) has become increasingly common, evidence supporting its long-term clinical benefit lags. This study evaluates mid-term functional and radiographic outcomes after posterior plating and identifies predictors of poor prognosis.
MethodsA consecutive cohort of 82 patients treated with posterior plating for PMFs between 2015 and 2018 was identified. Patients were recalled at a mean follow-up of 87.5 ± 10.3 months to obtain functional scores (AOFAS, OMAS, EQ-5D-VAS) and radiographic osteoarthritis grading. A unique subset of 35 patients, previously analyzed at short-term follow-up (mean 24.7 ± 8.1 months), was re-evaluated to assess longitudinal functional evolution within the same subjects. Multivariable linear regression identified independent risk factors.
ResultsFifty-five patients were evaluated (67% response rate). Multivariable analysis identified residual posterior step-off (≥ 1 mm) as a primary independent predictor of lower AOFAS (p = 0.035) and OMAS (p = 0.004) scores, and increased osteoarthritis severity (B = 1.31, p < 0.001). Preoperative CT findings suggestive of anterior syndesmotic involvement (ASI) were independently associated with progressive joint degeneration (B = 0.96, p < 0.001). Longitudinally (n = 35), mean AOFAS scores improved significantly by 15.1 points between short- and mid-term follow-up (72.5 vs. 87.6; p < 0.001), despite radiographic progression of osteoarthritis.
ConclusionResidual posterior step-off is a primary driver of poor mid-term results. Preoperative CT-based ASI is an independent risk factor for progressive radiographic degeneration. Functional recovery continues significantly beyond the 2-year follow-up.