Left knee pain and swelling. MENISCI: The menisci are intact.ARTICULAR CARTILAGE AND BONE: The superior aspect of the femoral trochlea is convex indicating dysplasia.There is lateral translation and tilting of the patella, with the lateral facet of the patella perched atop the lateral femoral condyle.There is severe degeneration of the articular cartilage along the medial facet of the patella with areas that appear to be essentially devoid of cartilage.There is a comma-shaped ossicle measuring just over 2 cm in greatest dimension along the inferomedial aspect of the patella which we suspect reflects an old fracture fragment related to prior patellar dislocation.There is also full-thickness degeneration of the articular cartilage along the median eminence extending slightly along the medial facet of the patella with mild subchondral edema type signal.There is focal full-thickness degeneration of the articular cartilage of the medial tibial plateau below the posterior horn of the medial meniscus with edema type signal in the underlying subchondral bone.The articular cartilage of the lateral compartment appears relatively well preserved.LIGAMENTS: The cruciate and collateral ligaments are intact. EXTENSOR MECHANISM: The quadriceps and patellar tendons are intact. The medial patellofemoral ligament is slightly indistinct which may reflect prior injury.The Insall-Salvati ratio is within normal limitsThe tibial tuberosity to the trochlear groove distance is nearly 3 cm.ADDITIONAL
1. Findings indicating patellofemoral instability including marked cartilage loss along the undersurface of the patella and an ossicle along the medial aspect of the patella that may reflect an old fracture from prior patellar dislocation. Furthermore there is increased tibial tubercle-trochlear groove distance as well as trochlear dysplasia.2. Small joint effusion and 2cm loose body in the posterior aspect of the joint.3. Small focal cartilage defect along the posterior aspect of the medial tibial plateau.