39-year-old male with left knee pain and inability to extend knee. Evaluate for meniscus tear versus chondral injury. MENISCI: There is intrasubstance signal within the body and posterior horn of the medial meniscus indicating degeneration. Although the signal is predominantly horizontally oriented and intrasubstance in nature, it also extends in a vertical fashion to the tibial articular surface within the posterior horn, at the red-white junction, suggesting an undersurface tear. Please note that we cannot determine whether this represents an acute or chronic tear in the absence of prior imaging for comparison. We see no frank fluid signal intensity within the medial meniscus. There is attenuation of the anterior horn of the lateral meniscus which may represent prior partial meniscectomy. There is also a small defect along the free edge of the junction of the anterior horn and body of the lateral meniscus compatible with a radial tear, although it is conceivable that this could be related to prior surgery. There are also multiple vertically oriented linear foci of intermediate signal intensity within the posterior horn extending to the tibial and femoral articular surfaces compatible with multiple vertical tears, although we cannot determine whether these are acute or chronic in etiology. We see no frank fluid signal intensity within the posterior horn.ARTICULAR CARTILAGE AND BONE: There is mild heterogeneity of the articular cartilage of the femoral trochlea centrally suggesting mild degeneration. There is near-full-thickness to full-thickness degeneration of the articular cartilage of the lateral femoral condyle above the posterior horn of the lateral meniscus. There is slight prominence of the subchondral bone at this site which raises the possibility of prior microfracture at this location. The articular cartilage of the posterior aspect of the tibial plateau appears slightly thinned.LIGAMENTS: The patient has undergone ACL reconstruction. The ACL graft appears intact. The PCL and collateral ligaments appear intact. EXTENSOR MECHANISM: There is a defect within the central patellar tendon with associated mild deformity of the inferior patella and tibial tuberosity indicating the donor site of the patient's ACL graft.ADDITIONAL
1. Medial and lateral meniscal tears as described above. Please note that we cannot determine whether these represent acute or chronic tears without the presence of prior imaging for comparison.2. Articular cartilage degeneration as described above.3. Subcentimeter loose body within the posterior aspect of the knee.4. Postoperative changes of prior ACL reconstruction.