A Case of a Extrasynovial Ossifying Chondrolipoangioma in the Infrapatellar Fat Pad: Advanced Stage of Hoffa's Disease

ABSTRACT

Hoffa's disease refers to inflammation, subsequent hypertrophy and impingement of the infrapatellar fat pad, and this is all triggered by acute trauma or repetitive microtrauma. Patients with Hoffa's disease manifest with anterior knee pain and functional impairment. The chronic impingement of the infrapatellar fat pad, which contains many progenitor cells, may promote fibrocartilaginous formation and osteochondral metaplasia of adipose tissue, so osteochondroma is sometimes found in patients with advanced Hoffa's disease. We report here on an ossifying chondrolipoangioma as an advanced form of Hoffa disease that occurred in the infrapatellar fat pad.