Heterotopic bone is a rare complication of burns. The factors to be considered in its development are the percentage of burn, the location of burn, the length of bed confinement, osteoporosis, superimposed trauma, and genetic predisposition. Characteristically, heterotopic bone develops between one and three months after the acute burn. It may continue to proliferate as long as there are open wounds but it tends to regress once the burn wound has healed. If it has bridged a joint it may be surgically excised after the burn has healed. The more extensive the heterotopic bone the poorer the prognosis for restoration of motion after excision. Prevention of heterotopic bone appears to be linked in part to early mobilization of the patient and recovery from the postburn hypermetabolic and catabolic state.