An osteochondral allograft is a piece of tissue taken from a deceased donor to replace damaged cartilage that lines the ends of bones in a joint. A section of cartilage and bone is removed, shaped to precisely fit the defect and then transplanted to reconstruct the damage.
The articulating surfaces of all the joints in the body are lined by a soft tissue called articular cartilage, which cushions the ends of bones. This allows easy gliding of the bones during movement of the joint. Injury and wear-and-tear can damage the cartilage, making it rough and sometimes expose the underlying bone. This leads to painful rubbing of the bones of the joint and disability.