Neurogenic heterotopic ossification : a diagnostic and therapeutic challenge in neurorehabilitation.

Heterotopic ossification (HO) is an important cause of restriction in range of movements and secondary motor disability following neurotrauma, orthopaedic interventions and burns. It has not received focussed attention in non-traumatic neurological disorders. In a prospective study of 377 patients, on medical problems in neurological rehabilitation setting, 15 subjects (3.97%) had neurogenic heterotopic ossification. Their clinical diagnosis was: transverse myelitis (7), neurotuberculosis (4), traumatic myelopathy (2) and stroke (2). Hip (10), knee (4) and elbow joints (1) were involved. The risk factors included urinary tract infection (15), spasticity (6), pressure sores (13) and deep venous thrombosis (DVT) (6). The initial diagnosis was often other than HO and included DVT (3), haematoma (2) and arthritis (2). ESR and serum alkaline phosphatase levels were elevated in all but one subject. The diagnosis of HO was established using X-rays, CT Scan and three-phase bone scan. Following treatment with non-steroidal anti-inflammatory drugs, the range of motion improved in only four patients. HO resulted in significant loss of therapy time during rehabilitation. High index of suspicion about this complication is necessary for early diagnosis and prompt intervention.