Transient lateral patellar dislocation complicated by chondral fracture
Presentation
Basketball injury.
Patient Data
There is a bone contusion of the medial aspect of the patella as well as the lateral femoral condyle with a chondral defect of the medial patellar facet. The detached cartilaginous fragments are displaced, well-visualized on the sagittal sequences behind the Hoffa's fat pad. Moderate joint effusion is noted. The medial patellar retinaculum is moderately thickened with no abnormal intrinsic signal or disruption seen.
Normal chondral thickness of the trochlear facets as well as the femoral condyles. No meniscal tear is seen. ACL and PCL are intact.
Case Discussion
In this case, the pattern of the bone contusion of the medial aspect of the patella, and the lateral femoral condyle is consistent with transient lateral dislocation of the patella complicated by chondral fracture.