Lower extremity free flaps: A review

OBJECTIVE: To identify factors related to free-flap coverage of lower extremity fractures that are linked to a negative outcome. DESIGN: A chart review. SETTING: A large microsurgical referral centre. PATIENTS: From 1981 to 1989, the records of all patients who underwent free-tissue transfer to the lower extremity with more than 1 year of follow-up were selected. From this was drawn a subgroup of 49 patients (mean age, 36 years) who had tibial fractures (55% were motor vehicle injuries) and in almost all cases established soft-tissue or bony defects. They formed the study group. INTERVENTION: Free-flap transfer. OUTCOME MEASURES: Factors that might be associated with free-flap failure: mechanism of injury, grade of tibial fracture, history of smoking, diabetes, peripheral vascular disease, ischemic heart disease, vascular compromise in the leg preoperatively, recipient artery used, type of anastomosis, and hypertension or hypotension intraoperatively. RESULTS: Type IIIB tibial fractures were the most frequent (67%) and carried a significantly (p = 0.02) higher risk of free-flap failure than other types of fracture. Patients underwent a mean of four procedures before referral for free-tissue transfer. The mean time from injury to flap coverage was 1006 days. Stable, long-term coverage of the free flaps was achieved in 78% of patients. Wound breakdown was most often caused by recurrent osteomyelitis (65%). Seventy-four percent of the fractures healed. The amputation rate was 10%. Four patients required repeat free-flap transfer for limb salvage. CONCLUSION: Only the grade of tibial fracture could be significantly related to postoperative free-flap failure.