30 year-old male with a history of osteochondral defect in the lateral femoral condyle presents with knee pain. MENISCI: Poorly defined increased signal intensity within the inner fibers of the posterior horn and body of the lateral meniscus likely represents intrasubstance degeneration and free edge fraying. These findings appear slightly more prominent compared to the prior study; this may represent progression of fraying or simply differences in technique (3T versus 1.5 T scanner).Again seen is poorly defined signal intensity within the anterior horn of the lateral meniscus suggesting additional intrasubstance degeneration. No fluid signal intensity is identified in the lateral meniscus. The medial meniscus is intact.ARTICULAR CARTILAGE AND BONE: Again seen is a linear focus of metallic susceptibility artifact in the lateral femoral condyle, compatible with an orthopedic screw that presumably affixes the patient's known osteochondral defect based on prior reports. Focal depression of the overlying subchondral bone plate appears similar to the prior study. Small cysts in the subchondral bone of the lateral femoral condyle, just above the free edge of the anterior horn of the lateral meniscus, also appear similar to the prior study. Thinning/heterogeneity of the overlying articular cartilage is not significantly changed, likely representing chronic degeneration. No large fluid-filled gaps are seen. Increased signal intensity within the articular cartilage of the lateral tibial plateau, just anterior to the free edge of the posterior horn of the lateral meniscus, appears more prominent; this finding suggests progression of full thickness cartilage degeneration. Abnormal increased signal intensity within the lateral tibial spine appears similar to previous MRI. Articular cartilage of the medial tibiofemoral compartment is intact. The patellar cartilage is also intact, but new increased signal intensity within the articular cartilage of the femoral trochlea suggests focal degeneration at this site. Tricompartmental osteophytes are again noted.LIGAMENTS: The cruciate and collateral ligaments are intact.EXTENSOR MECHANISM: The extensor mechanism is intact. Minimal thickening of the patellar tendon and scarring within Hoffa's fat pad are consistent with prior surgery.ADDITIONAL
1.Postoperative changes s/p lateral femoral condyle osteochondral defect fixation as described above, appearing similar to the prior MRI. However, there appears to have been progression of focal degeneration of the articular cartilage overlying the adjacent lateral tibial plateau.2.Degeneration and free edge fraying of the lateral meniscus, which may have slightly progressed since the prior MRI. However, no fluid-filled lateral meniscal tear is identified.3.New focal degeneration of the articular cartilage overlying the femoral trochlea and other findings as described above.