Nonarticular complication of heterotopic ossification: a clinical review.

Heterotopic ossification (HO) is a complication in neurologic lesions such as head injury and spinal cord injury. Limitation of range of motion and ankylosis as results of HO are well documented. In this report, ten instances of nonarticular complications after development of HO are described. There were three instances of vascular compression, five instances of ulnar nerve compression at the elbow, and two instances of suspected lymphedema. Clinical findings and radiographic evidence of these complications are described. Clinicians should be aware of these complications when HO is diagnosed. In addition, HO should be considered in the differential diagnosis of deep venous thrombosis in spinal cord injured and head injured patients.