Chronic instability of the foot and foot geometry: A radiographic study

textabstractMultiple factors are involved in chronic lateral instability of the ankle. The geometry of the foot may be of importance. A cavovarus foot may predispose to lateral ligament injuries. In the present study, standardized lateral X-rays were obtained of the feet of patients with chronic instability and of a control group. Four parameters were used: (1) the tarsal index as described by Benink; (2) the talocalcaneal angle; (3) the talometatarsal angle; and (4) the calcaneal angle. No relationship between lateral instability of the foot and foot geometry was found. The talocalcaneal angle as defined in this study was found to be a less appropriate parameter in measuring the longitudinal foot arch