Anatomy and circulation of the canine skin.

The skin of the dog has several anatomic differences from human skin. Skin thickness, hair growth, and circulation vary regionally in the dog and between breeds to some degree. Direct cutaneous arteries supply the canine skin. The deep or subdermal layer is closely associated with the panniculus muscle (where present) and should be elevated with the overlying skin during routine flap elevation or undermining procedures. Flaps in the dog elevated without inclusion of a direct cutaneous artery and vein have been termed subdermal plexus flaps to avoid confusing them with random flaps in the human based on musculocutaneous vessels. Axial pattern flaps developed for veterinary clinical use are discussed, several of which have potential for free flap transfer in cutaneous reconstructive surgery.