1. Anomalous arterial circulation at the ankle is present in 3 per cent of the population, and predisposes to arterial injury by severe inversion, plantar flexion of the ankle.
2. Arterial bleeding should be considered in the differential diagnosis of severe pain following inversion, plantar flexion, ankle sprains.
3. A case is presented with a post-traumatic false aneurysm of the perforating peroneal artery. This was associated with rupture of the anterior fibulotalar ligament, the anterior portion of the talocalcaneal ligament, and anterolateral ankle joint capsule. The patient had a satisfactory functional result following resection of the aneurysm and repair of the artery and damaged ligaments.