[Computerized tomography assessment of replacement of the cruciate ligaments of the knee]

January, 1993, to December, 1995, we examined with CT 44 patients submitted to surgical replacement of knee cruciate ligaments, namely 18 anterior cruciate ligaments (ACL) and 6 posterior cruciate ligaments (PCL). ACL was replaced with a patellar tendon graft (Eriksson technique) in 23 cases and with a semitendinous graft (Lindemann-Bousquet technique) in 7 cases. The autologous new ligament appeared as a laminar structure of intermediate density. The tendon had been covered with a synthetic lining (Leeds-Kejo) in 10 of the above cases, while the new ACL graft was completely synthetic in 8 cases, which synthetic allografts appeared hyperdense relative to autologous new ligaments. PCL replacement had been performed with Augustine technique (patellar tendon graft in a tibial tunnel) in 3 cases, with Hughston technique (medial gastrocnemius graft in a medial condylar tunnel) in 2 cases and with a synthetic graft (Gore-tex) in 1 case. Twelve of 38 new ACLs were injured (7 Eriksson, 3 Lindemann-Bousquet and 2 synthetic grafts): the injured new ligament was enlarged and hypodense, or involved in atrophic absorption. The new ligament was partially calcified in one of the 3 patients with PCL replacement with a patellar tendon graft (Augustine technique). The bone bract was dislocated in the intercondylar notch in a patient submitted to Hughston surgery because of proximal disinsertion of the new ligament. The Gore-tex new PCL was sinuous in the proximal tract, with intra-articular calcified loose bodies. CT adequately depicted surgical results and diagnosed the new ligament injuries and other articular abnormalities. MRI is currently the gold standard in the multiplanar studies of the postoperative knee, but CT can be confidently used to identify ligament injuries and intra-articular calcified loose bodies.