Varus Tilt of the Tibial Plafond as a Factor in Chronic Ligament Instability of the Ankle

The authors performed a radiographic study of 136 patients with acute ligament sprains and 85 patients with chronic lateral ligament instability of the ankle. Varus angulation of the tibial plafond, varus angulation of the line passing both malleolar ends, and varus angulation of the medial malleolus were measured on the AP views, and dorsal angulation of the tibial plafond was measured on the lateral views. The varus angles of the tibial plafond, the line passing both malleolar ends, and the medial malleolus were larger as mean values in patients with chronic ligament instability than in the patients with acute ligament sprain. The varus tilt of the tibial plafond is more often seen in patients with chronic ligament instability of the ankle than in patients with acute ligament sprains.