HETEROTOPIC OSSIFICATION

Heterotopic ossification (HO) is the process by which bone forms at an abnormal location, usually in soft tissue.

Heterotopic ossification (HO) is the process by which bone forms at an abnormal location, usually in soft tissue like muscle, tendons, and ligaments. While most people cannot feel the abnormal bone, they can see it. There is also unusual stiffness of the joint that accompanies HO. If you feel around the affected joint area, you may feel the mass of bone. There may also be pain. The elbow joint is a common area for HO to develop, which can make it difficult to move the joint (bending and straightening).

HO is caused by signal mix-ups in the body in which the bone cells begin to make new bone outside of the normal skeleton. This process of bone formation is similar to when you fracture a bone and new bone forms to heal the damaged site, except that the bone is formed in the soft tissues rather than at the site of the healing bone.

Treatment varies per patient. If the HO developed as a result of brain and spinal cord injuries or as a result of a fracture around the elbow, the heterotopic bone may be removed surgically. However, surgery is not recommended for those who have a genetic disorder that is causing the HO.