Free SIEA-flap transposition in a rat model with preservation of the limb circulation

An experimental rat model has been developed with transposition of the free groin flap to the dorsum of the rat to simplify postoperative monitoring and prevent autocannibalism. In existing models, the limb vessels are ligated when harvesting the flap. This can result in ischemia, and vasoactive factors having an impact on the microcirculation of the free flap may be released. In this study, a groin flap based on the superficial inferior epigastric artery (SIEA) was harvested in 12 Wistar rats. The transplant included a short segment of the femoral artery while the femoral vein was kept intact. The flap was transposed to the dorsum of the neck where the vessels were anastomosed. The divided femoral artery in the groin was reanastomosed. Nine (75%) of the 12 flaps were successful. The femoral anastomosis in the groin stayed patent in all cases. The microsurgical free-flap procedure presented has significant advantages compared to existing models and may be useful for practical microsurgical training and also for scientific purposes.