Abstract Two hundred and thirty-seven fractures of the ankle treated with non-rigid internal fixation were reviewed with regard to classification, congruency of joint surface, range of motion and the patients' subjective symptoms. The fractures were divided into either severe fractures consisting of two or more skeletal injuries or simple fractures consisting of only one skeletal injury. Successful operation, i.e. congruency of the joint, was seen in 50 per cent of the severe and in 73 per cent of the simple fractures (significant, P < 0.001). Disability was significantly more frequent after severe fractures and with incongruent joints. This study shows that the operative technique using non-rigid internal fixation is not sufficient for treating severe fractures, as exact anatomical reconstruction of the joint was not obtained.