MRI of anterior cruciate ligament repair with patellar and hamstring tendon autografts

Objective. Several MRI sequences were used to evaluate the 2-year postopera tive appearance of asymptomatic knee with a torn anterior cruciate ligament (ACL) reconstructed with bone-patellar tendon-bone (BTB) and semitendinosu s and gracilis (STG) tendon autografts. Design and patients. Two groups wit h successful repair of ACL tear with BTB (n=10) or STG (n=10) autografts we re imaged at 1.5 T with sagittal and oblique coronal proton density-, T2-we ighted and sagittal STIR sequences and plain and contrast-enhanced oblique coronal T1-weighted sequences. The appearance of the graft and periligament ous tissues was evaluated. Results. In all 20 cases, the ACL graft showed homogeneous, low signal inte nsity with periligamentous streaks of intermediate signal intensity on T2-w eighted images. In 10 cases, localised areas of intermediate signal intensi ty were seen in the intra-articular segment of the graft on proton density- and T1-weighted images. The graft itself did not show enhancement in eithe r of the two groups, but mild to moderate periligamentous enhancement was d etected in 10 cases. Conclusion. The MRI appearance of ACL autograft is variable on proton densi ty- and T1-weighted images. Periligamentous tissue showing contrast enhance ment is a typical MRI finding after clinically successful ACL reconstructio n.