There is a well-circumscribed anterior paraarticular oval mass within the infrapatellar (Hoffa's) fat pad. It appears isointense to the muscles on T1WI with a central area of high signal (isointense to the articular cartilage), heterogeneous high signal on PD fat sat sequences with a central area also isointense to the articular cartilage and peripheral hypointense rim (calcification). No enhancement is seen following IV contrast administration. Note mild oedema of high signal within of the infrapatellar fat pad with no lesion of the adjacent bone. An intraarticular effusion is noted. Grade 3 vertical oblique tear of the posterior horn of the medial meniscus.