Presentation
Trauma to the left knee.
Patient Data
Bone contusion of the medial aspect of the patella and the lateral femoral condyle with an osteochondral defect of the medial patellar facet. Moderate joint effusion is noted. The medial patellar retinaculum is thickened with abnormal intrinsic high signal but no evidence of disruption is seen.
ACL moderately thickened with intrinsic high signal but no rupture was seen.
Intact PCL, collateral ligaments and menisci.
The normal chondral thickness of the trochlear facets as well as the femoral condyles.
Case Discussion
MRI features of bone contusion of the medial aspect of the patella, and the lateral femoral condyle consistent with transient lateral dislocation of the patella complicated by an osteochondral fracture of the medial patellar facet.