Heterotopic ossification in civilians with lower limb amputations.

Objectives: To report the incidence of symptomatic heterotopic ossification (HO) in a defined civilian amputee population, describe its characteristics, and compare these findings to published data in military amputees.

Design: Retrospective chart analysis from July 1998 to July 2009.

Setting: Ambulatory amputee clinic within a large university medical center.

Participants: Adults with lower limb amputation (N=158).

Interventions: Not applicable.

Main Outcome Measure: Patients with symptomatic HO confirmed by radiographs.

Results: A total of 261 patients were evaluated; 158 met inclusion criteria, with 59% having traumatic etiology, 18% vascular etiology, 22% infection, and 1% tumor. Symptomatic HO was diagnosed in 36 (22.8%) patients, and 94% patients had mild HO on radiographic scoring. Rate of HO in amputations related to trauma was not increased compared with those of other etiologies. Surgical resection of the ectopic bone was required in 4 (11%) patients.

Conclusions: HO is seen commonly after civilian lower limb amputation regardless of etiology. The prevalence was less than that observed in previous reports from military populations. This is the first report estimating the prevalence of HO in adult civilian amputees.