Presentation
Knee trauma
Patient Data
There is a horizontal cleavage-type tear in the medial meniscus. ACL contour is disrupted with a change in the orientation, representing ACL complete tear.
There is mild fluid accumulation around the MCL representing MCL injury.
There is moderate joint effusion.
Note the characteristic bone marrow contusion in the posterolateral tibial plateau and lateral femoral condyle. If the impaction in the lateral femoral sulcus exceeded 2mm, it would represent a femoral notch sign which is highly suggestive of ACL injury.
Case Discussion
O'donoghue's unhappy triad consists of a medial meniscal tear, ACL tear, and MCL injury. It usually happens in pivot shift injuries. Today we believe that lateral meniscal tear actually happens more than a medial meniscal tear in this type of injury.