Evaluation of arthroscopic anterior cruciate ligament reconstruction using magnetic resonance imaging

Thirty-two patients who had arthroscopic anterior cruciate ligament reconstruction using a bone-patellar tendon-bone autograft underwent subsequent magnetic resonance imaging of the knee. A total of 32 magnetic resonance imaging examinations were performed from 10 days to 39 months postoperatively. The anatomic plane of the autograft was determined by obtaining a coronal pilot scan of the graft fixation screws or screw and staple. T1-weighted, T2-weighted, proton density, and gradient-echo imaging sequences were then obtained in the anatomic plane, as well as T1-weighted coronal images. The autograft was defined on the basis of visualization of fiber continuity on T2-weighted images as follows: 1) intact; 2) having a partial tear; or 3) having a complete tear. These results were then correlated with clinical examination and, in 10 cases, subsequent arthroscopy. Magnetic resonance imaging correlated with clinical findings in 31 of 32 patients. In addition, of the 10 patients who underwent subsequent arthroscopy, magnetic resonance scanning correlated in all cases with arthroscopic findings. T2-weighted and, in some cases, proton density images were most useful in visualizing the autograft. T2-weighted magnetic resonance imaging in the anatomic plane of the anterior cruciate ligament autograft can be a useful diagnostic tool in the evaluation of patients with patellar tendon anterior cruciate ligament reconstructions when graft integrity is in question.