Slipped capital femoral epiphysis: is the displacement always posterior?

The initial direction of displacement on slipped capital femoral epiphysis is generally accepted to be posterior as a consequence of retroversion of the femoral neck. We report the case of a 15-year-old boy with slipped capital femoral epiphysis in the medial direction, confirmed by three-dimensional computerized imaging. This was associated with an elongated neck without retroversion of the femoral neck. We suggest a correlation between elongated femoral neck with increased offset of the hip and the medial direction of slip. This case also underlines the need for precise definition of deformity prior to undertaking surgical treatment.