Fig. 10

Femoral condyle impaction injury. Panels of sagittal PD and PD FS images, in children except d. a Normal condylopatellar sulcus, a slight indentation in the condyle contour (arrows) without abnormal signal. b Contusion: subchondral marrow signal changes representing oedema (arrows), without cortical depression. c Impaction fracture: cortical depression (arrows) and oedema. Note also the large joint effusion. d Old impaction fracture: focal cortical depression and disruption (arrows), without subchondral signal change, in a 32-year-old woman who had an absent ACL and a history of prior football injury. There was also a tear of the posterior lateral meniscus, but the apparent cleft at the anterior aspect of the meniscus was a prominent transverse intermeniscal ligament rather than a tear