Prefabrication of a latissimus dorsi myocutaneous flap was performed in adult male Landrace pigs. Gelfoam sponges were used as a delivery system for basic fibroblast growth factor (bFGF) at the muscle-subcutaneous tissue interface. Skin survival and angiogenesis were augmented in the growth-factor-treated animals. These data support the use of basic fibroblast growth factor to enhance flap prefabrication.