Acquired genu recurvatum may have bone, capsulo-ligamentous or combined origins. It may affect the tibia or femur and various etiologies are possible. However, its pathogenesis is often linked to partial anterior epiphysiodesis following traumatic damage to the femoral or tibial growth plate. In this study we examine femoral recurvatum, a form which occurs only rarely. The clinical and radiographic characteristics are described in depth and the surgical indications for correction of this deformity are defined. Radiographic examination was used to complete the goniometry of the recurvatum deformity by calculating the dia-intercondylar angle, measureable on lateral radiographs of the knee. The normal value is 33 degrees (+/- 3 degrees) while in the patients with femoral recurvatum it was noticeably higher. In cases of isolated femoral recurvatum we carried out a supra-condylar osteotomy with removal of a bone wedge aimed at normalizing the dia-intercondylar angle. In the cases treated at our Centre, the objective, subjective, functional and radiographic results were good, with a mean follow-up of 6 years.
Clinical importance: as well as completing the goniometry of the recurvatum, the dia-intercondylar angle makes it possible to draw up a correct pre-operative plan, enabling precise surgical correction to be carried out.