Heterotopic bone formation in association with pelvic fracture and urethral disruption

Purpose: The initial and secondary management of pelvic fracture associated with disruption of the membranous urethra is the subject of a wide literat ure containing varied and controversial viewpoints. We have noted the prese nce of heterotopic bone formation surrounding the area of urethral injury i n patients undergoing delayed repair. We investigated the etiology, inciden ce and risk factors associated with such an injury, as well as potential me ans of prophylaxis. Materials and Methods: We reviewed the current literature on heterotopic bo ne formation with similar traumatic injury. While instances of severe ureth ral disruption of this type are fortunately rare in children, we describe p repubertal boys with such an injury complicated by heterotopic ossification . Results: The incidence of heterotopic ossification reported in children and adolescents is 3 to 15%, which is less than 15 to 80% reported in adults. Risk factors associated with traumatic heterotopic ossification include pro longed operating time, hematoma, formation, degree of bony debris, devitali zed muscle and concomitant infection. Prophylaxis with single low dose radi ation or nonsteroidal anti-inflammatory drugs has been shown to be effectiv e in the prevention of heterotopic ossification and may be beneficial in th is patient population. Conclusions: Heterotopic bone formation associated with severe traumatic in jury in the presence of devitalized tissue resulting in the pathological fo rmation of new bone is rare. This complication is only associated with the most severe pelvic fractures. Prophylaxis in these most severe cases with l ow dose radiation or nonsteroidal anti-inflammatory drugs can prevent the f ormation of heterotopic bone.