MR EVALUATION OF HUMAN ANTERIOR CRUCIATE LIGAMENT AUTOGRAFT ON OBLIQUE AXIAL IMAGING

Purpose: The purpose was to observe the changing MR appearance of stab le anterior cruciate ligament (ACL) grafts on oblique axial images. Me thod: Fifty-five knees in 44 patients were studied with MRI 1-54 month s after arthroscopic ACL reconstruction with double-looped autogenous semitendinosus and gracilis tendons. Knees with poor stability were ex cluded from this study. Examinations were performed at 0.2 T with SE p roton density and T2-weighted sagittal and oblique axial images. Resul ts: High signal intensity areas covered the grafts 1-3 months after su rgery. The high signal subsequently extended into the intertendinous b undles. The entire graft gradually became a low signal intensity bundl e again after 12 months. Grafts were classified by their appearance on the oblique axial images. Conclusion: We conclude that high signal in tensity can be seen within stable ACL grafts.