Radiographic evaluation of native anterior cruciate ligament attachments and graft placement for reconstruction - A cadaveric study

We examined seven cadaveric knees to determine the radiographic location of the native anterior cruciate ligament insertion sites as well as the location of tunnels used in anterior cruciate ligament reconstruction. Posteroanterior and lateral views at several flexion angles were taken with radiopaque markers around the insertions of the native anterior cruciate ligament and subsequent reconstruction tunnels. The femoral insertion was best seen on the 60 degrees notch view. On the lateral view, the femoral tunnel was easily seen as it crossed the roof of the intercondylar notch; however, because of the angle of the tunnel, the actual entrance into the knee may be well distal and anterior to this location. The tibial insertion and tunnel were easily seen at any flexion angle, The center of the insertion was 40% of the tibial diameter from the anterior margin. The lateral view in extension allowed determination of the tibial tunnel's location in relation to the intercondylar notch roof, but by itself did not allow accurate determination of the femoral tunnel's position. Notch and extension lateral radiographs together provided sufficient information for evaluation of anterior cruciate ligament graft position in a convenient, cost-effective format. Neither view by itself provides enough information to evaluate the position of the graft.