Indications and Outcomes of Free Tissue Transfer to the Lower Extremity in Children: Review

Thirty-four free tissue transfers for reconstruction of various tissue defects to the lower extremities were performed in 32 children over a 20-year period (1980 to 1999). Patient ages ranged from 3 to 19 years (mean: 10.8 years). Four donor sites were used: gracilis muscle, latissimus dorsi muscle, iliac crest osteocutaneous, and vascularized fibula. Fourteen patients had tissue defects related to trauma: nine received a gracilis flap; five received a latissimus dorsi flap. Five patients had tissue defects related to malignant tumor resection: three patients with Ewing's sarcoma received free fibulae; one patient with an osteogenic sarcoma received a gracilis flap, and another received an iliac crest osteocutaneous flap. Fifteen patients had congenital anomaly-related tissue defects: five with talipes equinovarus received gracilis flaps; ten with congenital tibial pseudoarthrosis received free fibulae. Vascular outcome was assessed based on the achievement of flap perfusion and post-surgical vascular revisions. Complete flap survival was achieved in 32 cases (85.3 percent); partial flap loss in three cases (8.82 percent); and complete flap loss in two cases (5.9 percent). Early revision surgery for the five partial or failed flaps consisted of debridement and split-thickness skin graft or flap removal. No patients required vascular take-backs or experienced vascular spasm. There were no systemic problems associated with the long and complex surgeries. Functional outcome was assessed based on ambulation, post-surgical complications, and whether the flap served its intended purpose. Ambulation was achieved in all cases. Functional surgical revisions were required in 32.4 percent of cases, and included scar revisions, flap debulking, bone grafts, and pin insertion. The most prevalent morbidity was persistent leg-length discrepancy (35.3 percent of cases). Only one successful flap was unable to meet its intended purpose, as a tibial pseudoarthrosis persisted, despite initial excision and a well-perfused reconstruction. Results show that free tissue transfer is safe and dependable for tissue defects of the lower extremity in children. From the authors' experience, free flaps used for the repair of defects from congenital tibial pseudoarthrosis have a high vascular success, but also require an extensive rehabilitation course, with only moderate functional success. There was no significant difference between flap surgeries performed immediately, intermediately, or late after trauma. These procedures have a wide range of indications and, despite the need for surgical revision and an extensive rehabilitation course, functional and vascular success can be achieved.