A large number of perforator flap types have been described in experimental and clinical studies. Perforator flaps have been used both as pedicled and free flaps in clinical practice, but only in a pedicled form in animal studies. According to the authors’ literature review, a free perforator flap in an animal model has not yet been developed. The purpose of this study was to describe a new free perforator flap model in the rat. A total of 15 Wistar rats weighing 200 to 250 g were used in this experiment. In 5 rats, the vascular anatomy of the popliteal vessels and their relation with adjacent structures were determined by anatomic dissection. In the remaining 10 rats, a posterior thigh perforator-based flap was created based on the distal popliteal vascular pedicle. In 5 rats the flap was transferred to the groin region as a free flap. In the remaining 5 rats the flap was transferred to the groin region, but in this group anastomosis was not performed between the vascular structures of the flap and the recipient femoral vessels. The latter group was designated as the control group. Direct observation and microangiographic techniques were used to assess the viability of the flap. Results showed that the cutaneous islands of all the free flaps survived completely, whereas in the control group all the flaps under-went total necrosis. The authors conclude that the free posterior thigh perforator flap is a reliable and true perforator flap model for future physiologic, biologic, and pharmacologic studies. It offers the following advantages: 1) Arising from the biceps femoris muscle, the musculocutaneous perforator of the flap has a consistent vascular pedicle, 2) it is the first free perforator flap for the rat, 3) it is harvested from a small-animal species, and 4) it can be used without the need for an isogeneic rat.
In recent years, although free perforator flaps have been used frequently in clinical practice to repair defects, 1–7 questions remain regarding their basic physiology. There is insufficient knowledge about flap hemodynamics, physiology, and wound-healing properties in free perforator flaps. Most experimental works, including metabolic, pharmacologic, vascular, and immunologic studies, are not applicable to humans. To overcome these drawbacks, experimental flap models are needed in inexpensive animal species. Although various perforator flap models have been described as pedicle flaps, 8,9 there is no free perforator flap in an animal model. The purpose of this study was to describe the first free perforator flap model-namely, the free posterior thigh muscle perforator flap-in a favored laboratory animal to provide a means for future various types of investigations.