The results of a study after 1 and 2 years of a prospective randomised trial of operative versus conservative treatment of ankle ligament rupture, demonstrate that purely functional orthotic therapy is the method of choice. This relates both to patient need and economical considerations. The trial demonstrated that without an operation it was possible to achieve a high degree of mechanical stability, a reduction of work disability time down to 3 weeks and full sports capability within 3 months. Consequently, and as a result of the trial, the only remaining surgical indications would seem to be dislocations of the foot and ankle, ankle ligament rupture with additional intra-articular pathology, and second-stage injuries or re-ruptures. The joint-stabilising function of the prototype splint developed in this study was improved on the basis of experimental investigations, using a Y-shaped leather band (designated CALIGAMED), which is available in 6 sizes for right and left ankle.