Free microvascular transfer of coccygeofemoral muscle in rabbits

A new experimental free flap model, the cocygeofemoral muscle flap of the rabbit, is introduced in this study. The coccygeofemoral muscle is a superficially located triangular muscle originating from the sacrum and inserting into the lateral condyle of the tibia, and it abducts the thigh. Anatomical dissection and microangiographic studies revealed that it has a major and a minor pedicle, the former originating from the caudal gluteal artery, and the latter originating from the caudal femoral artery. Its major pedicle contains the 0.7-mm artery, 1-mm vein, and the single nerve originating from the inferior gluteal nerve. In flap studies in 10 animals, the distal minor pedicle was ligated, and muscle was dissected up to its major pedicle and denervated, and the free muscle was transferred to the contralateral inguinal region via end-to-end anastomosis to the recipient vessels (i.e., the femoral artery and vein). At postoperative day 7, the transferred muscles were harvested and histologically examined. Nine of 10 muscles were viable; the coccygeofemoral muscle free flap is believed to be an easy-to-dissect and bulky flap model, having a relatively thick pedicle. It may serve as a good model in free muscle flap studies.