Heterotopic ossification as a complication of the staged total thigh muscles flap in spinal cord injury patients.

Between 1980 and 1990, 24 total thigh flap procedures were performed at Rancho Los Amigos Medical Center (Downey, CA) by the Pressure Ulcer Management Service. An unexpected occurrence was identified, that is, the rapid development of heterotopic ossification (HO) occurring in the exposed muscle flap between the first and second stages. There were 15 two-stage total thigh flap procedures on 14 patients performed between 1980 and 1990. Of these 15 flap procedures, 11 in 10 patients were found to have HO evident at the second-stage debridement/closure. In comparing our findings with those in other studies (earliest evidence of HO at 19 days), the initial presentation of HO in affected tissues might be even earlier than previously detected. The risks and technical difficulties due to development of HO associated with the two-stage total thigh flap procedure point toward future modifications in preoperative planning that may prove beneficial. Therefore, if the two-stage total thigh flap procedure is necessary, the interval between initial debridement/disarticulation (stage 1) and definitive flap closure (stage 2) should be kept to an absolute minimum. Additionally, HO medicinal prophylaxis (that is, indomethacin or diphosphonates) or radiation after the first stage of the total thigh flap procedure should be considered. Our final conclusion is that the total thigh flap procedure should be done as a one-stage procedure if possible.