Evaluation of the cruciate ligaments by CT.

Delineation of the cruciate ligaments in 112 patients using the computed tomography under arthrographic conditions was reported. Special position were used allowing for the demonstration of both cruciate ligaments in their complete lengths. In 6.2% of the examinations a reliable demonstration of the cruciates was not possible for technical reasons. Demonstration of normal cruciate ligaments in CT arthrography was described and normal values were tabulated. Recent cruciate ligament injuries were seldom examined by CT arthrography since the clinical symptoms were mostly unequivocal. The old ruptures of the ACL were divided into 4 different types: Type I: Rupture of the femoral origin that adjoins the PCL. Type II: Attenuation of the intraligamentary ruptured ligament with a preservation of origin and insertion. Type III: Complete rupture with shrinking and retraction of the fragments. Type IV: Osseous involvement of the femoral origin or tibial insertion. In 36 old cruciate ligament ruptures, the sensitivity of this method of investigation was 97%, the specificity 100%. After reconstructive surgery, CT arthrography allows for an objective analysis of the operative results and permits the comparison of different techniques of surgical repair.