Aneurysmal bone cysts of the patella secondary to chondroblastoma. Case reports

: Three cases of aneurysmal bone cysts secondary to chondroblastoma of the patella are described. This association is not particularly uncommon, but its occurrence in the patella is unusual. Treatment consists of curettage and bone grafting; however, if the patella is grossly enlarged or distorted, patellectomy is preferable.