[Ultrasound diagnosis of acute rupture of the anterior cruciate ligament. An experimental and clinical study].

In an experimental study on 20 cadaver knee joints we found examined the ventral translation of the tibial head, which is otherwise shown by the Lachmann test, by dorsal sonography. These examinations were performed in knees in which arthroscopical examination had confirmed intact ACL. After endoscopical partial and complete rupture of the ACL the examinations were repeated. Radiological examination was performed as a reference method. In a sonographically standardized clinical study of 243 traumatized knee joints the ventral translation of the tibial head was evaluated. In all knee joints examined an arthroscopy or arthrotomy was performed. In 56% a rupture of the ACL was verified. There was a positive correlation between translation of the tibial head by 3 mm or more compared with the non-injured side and a rupture of the ACL (sensitivity 0.95; specificity 0.98). The dynamic sonographic technique is a simple and highly sensitive specific diagnostic method that can be used to quantify the results found on clinical examination.