Heterotopic ossification about the elbow: a therapist's guide to evaluation and management.

Heterotopic ossification (HO) is a form of pathologic bone that often occurs in the elbow after a substantial traumatic injury and can complicate the functional outcome of the affected upper extremity. This article is designed to help the treating therapist better understand the complex process of HO. The pathophysiology, causes, associated risk factors, and signs and symptoms of HO are discussed in depth. The physician's management, including a classification system, diagnostic tools, and prophylactic measures, are explained. An extensive review of the literature regarding the therapist's management of HO reveals current misconceptions about passive range of motion (PROM). Traditional thought has advocated that PROM is a contraindication when HO is present because it can lead to the development or exacerbate the formation of HO. A review of the literature only reveals a few scientific studies that concluded that forcible manipulation of stiff joints can lead to myositis ossification. Most of the articles that have concluded that PROM is contraindicated have been erroneously based on anecdotal findings. This conclusion is misleading because forcible manipulation of a joint is not synonymous with PROM exercises. This article challenges popular belief and offers some alternative thinking for the therapist treating an elbow injury with HO as well as guidelines for the rehabilitation program.