Large expansile lesion affecting the patella with cortical thinning. It extends to the subarticular surface posteriorly but not into the knee joint. There are numerous fluid-fluid levels, and at the anterior aspect there is a thick area of solid tissue enhancement, with enhancing septa also present. Adjacent soft tissue oedema.
Quadriceps tendon, patellar ligament, MPFL and LPFL are normal in signal and variably insert/originate from areas of tumour, thinned cortex and residual normal patella.