Heterotopic Ossification

Synonyms

HO

Definition

Heterotopic ossification (HO) is a formation of lamellar bone in soft tissues following brain or spinal injury (Hendricks et al. 2007). HO usually involves the large joints of the body such as the hip, elbow, shoulders, and knees. In cases of traumatic brain injury, one of the most common sites is the hip. In cases of spinal injury, HO always occurs below the level of injury. Research has not clearly identified the causes of HO (Genet et al. 2011). Some have suggested that connective tissue cells change their characteristics into bone-forming cells as some type of inflammatory reaction to injury. Individuals with other bone-forming disorders such as ankylosing spondylitis, Paget disease, and idiopathic skeletal hyperostosis are at the risk for HO following traumatic brain or spinal cord injury (Almangour et al. 2016).

HO resultant from brain injury may not remit and can create considerable pain and disability for a brain injury patient (Cullen et al. 2007)....