Presentation
Retropatellar pain.
Patient Data
Knee joint alignment is normal. No joint effusion or loose intra-articular body identified. The posterior cruciate ligament is intact. The anterior cruciate ligament is intact however it is thickened and hyperintense.
The medial meniscus is intact. The medial collateral ligament is normal. Cartilage of the medial compartment is normal.
The lateral meniscus is intact. The lateral collateral ligament is normal. Cartilage of the lateral compartment is normal. The popliteus tendon and posterolateral corner structures are normal.
There is increased signal representing edema within the superior lateral corner of Hoffa's fat pad, as it impinges between the lateral femoral trochlea and patellar tendon. No associated patella alta or patellar lateralization. Patellofemoral alignment and cartilage is normal. The quadriceps tendon and patellar ligament are normal. Extensor retinaculum is unremarkable. The iliotibial band is normal.
No abnormal bone marrow signal. Incidental bone island within the medial tibial plateau. The popliteal fossa is normal.
Conclusion
- Mucoid degeneration of the ACL.
- Superolateral impingement of Hoffa's fat pad between the lateral femoral trochlea and patellar tendon.