30-year-old male patient with instability and concern for ACL tear. MENISCI: Posterior horn of the medial meniscus is diminutive in size, which may be due to prior meniscectomy, and contains abnormal increased intrasubstance signal intensity. There is a complex undersurface tear of the posterior horn of the lateral meniscus as well as capsular separation at the periphery. There is increased intrasubstance signal intensity within the anterior horn of the lateral meniscus, compatible with degeneration.ARTICULAR CARTILAGE AND BONE: There is subjective mild thinning of the articular cartilage of the medial patellar facet. There are no fluid-filled cartilage defects in the patellofemoral compartment. There is mild thinning of the weightbearing portions of the medial and lateral compartments without focal fluid-filled cartilage defects. Abnormal signal intensity within the lateral condyle may be secondary to patient's prior arthroscopy. Medial and lateral compartment osteophyte formation is noted.There are at least three screws in the proximal tibial metaphysis, one screw and multiple staples in the distal metaphysis of the femur, and one screw in the proximal lateral fibula.LIGAMENTS: The anterior cruciate ligament graft is thinned, compatible with at least partial tearing. There is mild buckling of the posterior cruciate ligament. The medial collateral ligament, lateral collateral ligament complex, and patellar retinacula are intact. There is perhaps atrophy of the biceps femoris, greater than expected for patient's age.EXTENSOR MECHANISM: The extensor mechanism appears intact.ADDITIONAL
1.Thinning of the anterior cruciate ligament graft and mild buckling of the posterior cruciate ligament is suggestive of at least a partial tear.2.Postsurgical changes from prior surgeries as described above.3.Complex undersurface tearing of the posterior horn of the lateral meniscus with capsular separation. 4.Diminutive posterior horn of the medial meniscus may be from prior meniscectomy.5.Osteoarthritis most prominent in the weight bearing portions of the knee.