抄録
One hundred and twenty knees in 90 patients, 1 to 60 months after arthroscopic anterior crucate ligament (ACL) reconstruction with double-looped autogenous semitendinosus and gracilis tendons were studied by magnetic resonance (MR) imaging. The knees with poor stability were excluded from this study. Examinations were performed at 0.2T with spin echo proton density sagittal and oblique axial images.
The percentage of grafts with high signal intensity on sagittal images increased up to 12 months after surgery, and then decreased over the subsequent 12 months. The mean signal intensity of the grafts in the 7 to 12 and 13 to 18 month postoperative groups was significantly higher than in the 1 to 3 month group. The mean signal intensity of the grafts in the 19 month and greater group was significantly lower than in the 7 to 12 month postoperative group.
On oblique axial images, high signal intensity areas covered the grafts 1 to 3 months after surgery. The high signal intensity subsequently extended into the intertendinous bundles. The entire graft gradually became a low signal intensity bundle again after 12 months.
MR high signal intensities observed in functional ACL grafts may depict the normal remodeling process of grafts.
