[Results of diagnostic sonography in injuries of the knee joint].

In an experimental study we examined three knee specimens with regard to the value of ultrasound for imaging soft tissue structures. Afterwards we documented artificial lesions of the menisci and ligaments. With this experience we started a prospective study of 101 patients suffering from acute knee injuries or chronic knee complaints. We compared the results of preoperative ultrasound investigation done by two different examiners with the final diagnosis after arthroscopy. For ultrasound evaluation we used a 5 MHz linear and a 7.5 MHz sector scanner. In both the experimental and the clinical study the menisci were well visualized. For medial meniscus lesions the less experienced examiner reached an accuracy and a predictive value of 81%. For the lateral meniscus the accuracy was 80%, although there was only a predictive value of 7% because of a high number of false positive results. The more experienced examiner got an accuracy of 83% and a predictive value of 91% for medial meniscus lesions. For the lateral meniscus the accuracy was 89%, however, the predictive value was only 22%. Both examiners were not able to detect ACL-ruptures surely. But ultrasound was useful to visualize Baker-cysts, bursitis, and jumpers-knee.