Warfarin in prevention of heterotopic ossification.

Patients with spinal cord injuries among others, commonly develop neurogenic heterotopic ossification. Current treatment with Didronel (disodium etidronate) inhibits bone matrix mineralization but not matrix production. To eliminate much morbidity and cost, a more efficatious prophylactic treatment is desirable. Because one of the proteins in bone, osteocalcin, is produced by a vitamin K-dependent carboxylation, this raises the possibility that treatment with warfarin may prevent the formation of ectopic bone. In the present study, 227 cases of spinal cord injury were reviewed. Among these patients, 15% were treated with warfarin and another 15% developed heterotopic ossification. None of the patients who were treated with warfarin developed heterotopic ossification, thus suggesting that warfarin may inhibit heterotopic ossification. Further prospective studies are planned.