A new experimental flap model in the rabbit: scapular osteomyocutaneous flap.

Despite the use of various types of osteomyocutaneous flaps in clinical practice, there are many unanswered questions regarding their basic physiology. Simple and reliable flap models are needed to investigate these problems. However, very few of these flap models have been described in small animals to date. The purpose of this study was to develop a new osteomyocutaneous flap model in the rabbit. Twenty adult New Zealand white rabbits, weighing 2.5 to 3.0 kg, were used in the reported experiment. In seven rabbits, the anatomy of the axillary vessels was studied by anatomic dissection and selective angiography. Based on this anatomic study, a new osteomyocutaneous flap, namely, the scapular osteomyocutaneous flap, is described in the rabbit model. The flap is composed of a skin island (16 x 8 cm) in the scapular region, the latissimus dorsi and intrinsic shoulder muscles, and the whole scapula as the bony component The flap is based on the axillary vessels, while the skin island and the latissimus dorsi muscle are independently supplied by branches of the thoracodorsal vessels. The flap could thus also be considered as a combined flap model. As an island flap, the flap was replaced in situ in eight rabbits, and transferred to the anterior chest in two rabbits. In the remaining three animals, the flap was transferred to the groin as a free flap. The viability of each component of the flap was demonstrated by direct observation, microangiography, bone scintigraphy, India ink injection study, and histologic examination. The authors concluded that the flap is a simple and reliable osteomyocutaneous flap model, since its dissection is easy; there is a long vascular pedicle with large vessel diameters; and large amounts of skin, muscle, and bone are included.