Traumatic instability of the proximal tibiofibular joint.

Proximal tibiofibular instability, seems to be an infrequently diagnosed abnormality, which occurs in isolation or in combination with fractures of the leg and ankle. Four types of instability are distinguished: subluxation, anterolateral dislocation, posteromedial dislocation and superior dislocation. The method of treatment depends on the type of dislocation and on the presence or absence of dysfunction of the peroneal nerve. The methods of treatment are described. Ten patients treated for this instability are presented. The use of radiographs to define the lesion is discussed. Radiographs, taken at follow-up, showed degenerative changes in the proximal tibiofibular joint in 8 of the 10 patients.