8-year-old female with history of left knee injury. MENISCI: No significant abnormality noted.ARTICULAR CARTILAGE AND BONE: No bone contusions are evident. The articular cartilage is intact.There is a 1.5 cm cortically based T2 hyperintense lesion with sclerotic borders located about the posterior aspect of the distal femoral metaphysis.LIGAMENTS: The ACL is not well visualized at its femoral insertion. Nonspecific low signal intensity band resting along the top of the tibial plateau likely represents residual ACL fibers. The PCL, LCL, and MCL are intact.EXTENSOR MECHANISM: The extensor mechanism is intact.ADDITIONAL
1. Complete ACL rupture at its femoral insertion. Given lack of bone contusions and significant joint effusion, this likely represents a chronic tear. The menisci are intact.2. Probable benign NOF along the posterior aspect of the distal femoral metaphysis.