1. In a series of fifty-one severely "sprained" ankles, twenty-three were shown to be spontaneously reduced and four to be recurrent subluxations of the ankle. Seven of twentyfour stable ankles had persistent disability for as long as five months when treated by itsjection and strapping.
2. By observing the course of the lateral ligaments and the effect on ankle stability of cutting them in various combinations, it is concluded that:
A. The anterior talofibular ligament is the important component of the fibular collateral ligament of the ankle.
B. Inversion films in severe ankle " sprains" should be taken with the foot in equinus, unless there is tenderness posterior to the fibula (which indicates injury to the posterior talofibular ligament). In this event the foot should be inverted with the ankle at 90 degrees.
3. Unstable ankles should be immobilized in walking plaster for about six weeks and should then be strapped with elastoplast for an additional two or three weeks.