[The anterior instability of the ankle joint in lateral ligament lesions (author's transl)].

In 50 unbiased ligamentous ruptures of the lateral ankle the anterior and the lateral instability of the ankle was evaluated by x-ray-pictures under strain. With increasing talar tilt the anterior instability also increased. But in some cases an isolated anterior and an isolated lateral instability could be found. The routine use of the x-ray-picture under strain in the sagittal plane is recommended, because the isolated rupture of the anterior fibulotalar ligament can be detected only by this mean.