Postoperative results after open-wedge high tibial osteotomy with lateral hinge fracture.

Abstract

BackgroundLateral hinge fracture (LHF) is a known complication of open-wedge high tibial osteotomy (OWHTO), potentially resulting in postoperative instability, displacement, loss of correction, malunion, and non-union. This study tested the hypothesis that patients who develop LHF after OWHTO can achieve clinical outcomes comparable to those without LHF, without requiring additional surgical intervention.MethodsThis retrospective study included 96 patients who underwent OWHTO with a locking plate between 2019 and 2021. Postoperative radiographs and computed tomography (CT) scans identified LHF in 24 patients (25%). Lower limb alignment was assessed using whole-leg standing radiographs at 6 weeks, 3 months, 6 months, and 12 months postoperatively. Clinical outcomes were evaluated using the Hospital for Special Surgery (HSS) score, Knee Society Knee Score (KS), and Function Score (FS).ResultsIn patients with LHF, the mechanical axis was 59.0 ± 7.4% at 6 weeks, 57.7 ± 7.8% at 3 months, 55.9 ± 9.5% at 6 months, and 53.9 ± 12.2% at 12 months. In patients without LHF, the corresponding values were 58.5 ± 6.1%, 57.8 ± 6.7%, 56.7 ± 7.0%, and 55.6 ± 7.4%, respectively. Although the mechanical axis decreased by 5.2% in the LHF group and 2.9% in the non-LHF group by 12 months, the difference was not statistically significant (p = .219). Similarly, the longitudinal change in alignment did not differ significantly between groups (p = .743). Postoperative clinical scores improved in all patients, with no significant differences between groups regardless of LHF status.ConclusionPatients who experienced LHF following OWHTO demonstrated comparable clinical outcomes and alignment correction to those without LHF, suggesting that LHF does not adversely affect postoperative results.