[Reconstruction of the anterior cruciate ligament with patellar tendon. Comparison between magnetic resonance and computerized tomography].

CT and MR potentials were compared in 30 patients submitted to anterior cruciate ligament reconstruction using the patellar tendon. In each patient the clinical data were correlated with the following radiologic parameters: the course of the tibial and femoral tunnels, their intraarticular outlet sites and their shape, the shape of the intercondylar notch and of the medial wall of the lateral femoral condyle and, finally, the shape of the graft and of the synovia. The intraarticular outlet site of the tibial tunnel was studied on the sagittal or transverse planes. In the former case the distance from the anterior tibial edge was considered, together with its relationship to sagittal tibial depth. The intraarticular outlet site of the femoral tunnel which was studied on sagittal and coronal MR planes was determined at CT by calculating its distance, i.e., the number of scans, from the intercondylar notch and from the posterior edge of the femoral condyle. MRI yielded better results thanks to its multiplanarity, but CT proved superior in defining size and shape of the bone outlets, the presence of bone chips (sometimes responsible for synovial reaction), the shape of the intercondylar notch and of the medial wall of the lateral condyle. As regards graft visualization, both CT and MRI yielded satisfying results in most cases. Nevertheless, MR potentials appeared superior thanks to its capabilities in demonstrating the graft in its full length and in differentiating it from surrounding synovial reaction.