Tarsal hypermobility after ankle fusion--fact or fiction?

Thirty-seven patients have been reviewed after arthrodesis of the ankle in order to determine the reduction of dorsiflexion and plantarflexion of the foot, the incidence of tarsal hypermobility and its relevance to the clinical results of this procedure. Radiological methods of measuring movements in the foot and tarsus are described and applied to patients who had a normal foot on the opposite side which could be used as a control. Our findings suggest that tarsal hypermobility is not as common as has hitherto been supposed and that a stiff foot with minor radiological degenerative changes in the tarsal joints is quite compatible with an excellent result.