Osteochondritis dissecans (OCD) occurs when a small segment of bone begins to separate from its surrounding region due to a lack of blood supply. As a result, the small piece of bone and the cartilage covering it begin to crack and loosen. When it affects the ankle, it typically occurs on the talus, the small ankle bone between the shin and the heel bone. It is sometimes also known as an osteochondral fracture of the talus, chip fracture of the articular surface or a chondral fracture of the talus.
A Answers (2)
Oteochondritis dssecans occurs when there's a problem with blood supply to the elbow and part of the bone chips off. The chipped part of the bone stays loose in the joint capsule, and the little fragment gets stuck in the muscle and causes irritation every time you move your elbow around. The problem is more commonly seen in knees than in elbows.
(This answer provided for NATA by the Southern Utah University Athletic Training Education Program.)