Infections after high tibial open wedge osteotomy: a case control study

High tibial open wedge valgisation osteotomy (HTO) is a widely used procedure for the treatment of unicompartimental osteoarthritis of the knee. Instead of the classical paramedian longitudinal skin incision, some advocate an oblique incision, in order to get a better exposure of the postero-medial aspect of the tibial head, while reducing strain on the soft tissues. Risk factors for surgical site infection were analysed. Retrospective analysis of all cases of HTO performed in a single institution between January 2000 and June 2006. A total of 106 patients underwent 110 HTO during the study period. The standard longitudinal incision had been used in 90, oblique incision in 20 cases. Four infections occurred, all with an oblique incision. This was the only factor showing a statistical significant association with surgical site infection (P = 0.001). The oblique incision is the only parameter with statistical significant association with infection after HTO. As this study type cannot prove causality, it is recommended to perform oblique incision only after careful evaluation of risks and benefits.