Male 39 years old Reason: s/p ACL recon by Dr. Martin Leland. Check for ACL re-tear versus meniscus re-tear. History: knee pain and swelling. MENISCI: Again seen is vertically-oriented increased signal intensity within the peripheral fibers of the posterior horn of the medial meniscus indicating a longitudinal tear. The tear is less prominent on the current study than on the prior study and contains intermediate and low signal intensity suggesting prior repair and partial healing. However, there is a vertically oriented linear focus of higher signal intensity within the inferior aspect of the tear that is suspicious for a focal retear of the undersurface of the meniscus. Additionally, there is a small focus of increased signal intensity more anteriorly along the undersurface of the red/white zone of the posterior horn of the medial meniscus, likely representing a new undersurface tear. The anterior horn and body of medial meniscus appear intact.There is mild deformity of the root of the posterior horn of the lateral meniscus, likely representing repair of a tear at this location, but we see no findings to suggest retear or new tear of the posterior horn. There is, however, a new partial thickness radial/oblique tear of the anterior horn of lateral meniscus.ARTICULAR CARTILAGE AND BONE: There is focal loss of cartilage along the posterior aspect of the medial tibial plateau beneath the meniscal tear, with edema type signal in the underlying bone. There is also mild heterogeneity of the articular cartilage of the weight-bearing portion of the medial femoral condyle suggesting mild degeneration with mild edema type signal in the underlying bone. There is increased signal intensity within the articular cartilage of the lateral femoral condyle above the posterior horn of the lateral meniscus, likely representing focal degeneration, with a cyst in the underlying bone that is new when compared with the prior study. There is a full thickness cleft through the articular cartilage of the medial facet of the femoral trochlea, with degeneration of the articular cartilage. This appears slightly more extensive on the current study than on the prior study. There is mild edema within the medial tibial spine; this is nonspecific.LIGAMENTS: Patient is status post ACL reconstruction. The anterior cruciate ligament is heterogeneous in signal, perhaps due to "neo-ligamentization", but fibers can be traced from the femur to the tibia and we see no specific features of a retear. The posterior cruciate ligament is intact. The medial collateral ligament is abnormally thickened, indicating prior injury, but we see no fluid filled tear at this time. The lateral collateral ligament complex is intact. EXTENSOR MECHANISM: There are chronic enthesopathic changes within the distal quadriceps, but otherwise the extensor mechanism is intact.ADDITIONAL
1.ACL reconstruction as described above, with heterogeneous signal intensity of the graft that is favored to represent "neo-ligamentization" rather than tearing.2.Intermediate to low signal intensity tissue anterior to the graft may represent residual torn ACL fibers, but we cannot exclude the possibility of focal arthrofibrosis ("cyclops lesion").3.New radial tear of the anterior horn of the lateral meniscus.4.Findings suggestive of new and recurrent undersurface tears of the posterior horn of the medial meniscus.5.Cartilage abnormalities and other findings as described above.