29-year-old male presents with acute left knee pain. MENISCI: Lobular intermediate signal with a more discrete linear component extending to the inferior articular surface in the posterior horn of the medial meniscus compatible with a tear. There is a small posterior parameniscal cyst. There is minimal extrusion of the menisci. No discrete tear involving the medial meniscus is identified.ARTICULAR CARTILAGE AND BONE: Bone marrow edema is noted in the lateral tibial plateau and lateral femoral condyle. There is some heterogeneity in the articular cartilage of the patellofemoral joint but no focal thickness tear is identified. There is however a focal cartilage defect with abnormal signal along the lateral aspect of the lateral condyle with underlying bone marrow edema.LIGAMENTS: Abnormal diffuse intermediate signal intensity throughout the anterior cruciate ligament with a full-thickness tear and proximal retraction of the ligament towards the origin. Abnormal appearance and signal of the MCL compatible with a severe sprain with suspicion for proximal tearing. High signal intensity through the lateral collateral ligament complex to a lesser degree is suggestive of a sprain.EXTENSOR MECHANISM: The extensor mechanism is intact.ADDITIONAL
Complete thickness tear of the ACL with associated tears of the lateral meniscus. Findings are also concerning for a high-grade MCL sprain with likely superimposed proximal tearing.