The stress-tenogram is a radiological technique for the investigation of injuries to the lateral ligament of the ankle, and combines the information previously provided by inversion and anterior stress radiographs, and the peroneal tenogram. It is designed to differentiate between stable and unstable ankles, and between isolated ruptures of the anterior talofibular ligament and combined tears of the anterior talofibular and calcaneofibular ligaments. A high degree of diagnostic accuracy has been confirmed at operative repair in a group of thirty-two patients.