Behavior of the graft within the bone tunnels following anterior cruciate ligament reconstruction, studied by cinematic magnetic resonance imaging.

Abstract

The behavior of a ligament graft following cruciate ligament reconstruction is still an area of limited knowledge. Cinematic magnetic resonance imaging (MRI) offers the possibility of visualizing the graft, including the graft tunnels and fixation during knee motion. Twenty-three patients underwent cinematic MRI (0. 2 T; Artoscan) mean 23.4 months (range 14-39 months) after autologous anterior cruciate ligament reconstruction (eight bone-tendon-bone, seven semitendinosus-gracilis, and eight iliotibial band). The images were read without knowledge of the clinical condition or the type of surgery performed. Signal intensity and continuity of the anterior cruciate ligament reconstruction and movement of the graft in the tibial or femoral tunnel anteriorly and posteriorly were noted. In two of the 23 patients the graft (semitendinosus-gracilis) moved in the tibial canal. The initial 9-mm tunnel had expanded by 2 mm in the anteroposterior direction at the entrance to the joint space. Only these two had a slight knee laxity, with a side-to-side difference in anterior translation measured by the KT-2000 of 4 and 5 mm. No movement was observed in any of the femoral tunnels. Cinematic MRI thus makes it possible to study graft behavior within the bone tunnels.