Our revised classification of skin flaps and opinion for 2004 classification of skin flaps

Vascular systems of the flaps are constructed of following elements; i) types of blood circulation in the flaps, ii) vessel types of vascular pedicles, iii) separation points of vascular pedicles. The blood circulation of flaps is constructed of the dermal vascular system and the subdermal vascular system. Based on the combination of these elements, skin flaps can be categorized into the thin cutaneous flap, the split thickness cutaneous flap, and the full thickness cutaneous flap. The blood circulation in the deep fascia itself is poor, and thus the deep fascia does not contribute to the blood supply of the cutaneous flaps. Accordingly, the cutaneous flaps containing the whole subcutaneous adipose layer without deep fascia is basically similar to the fasciocutaneous flap. However, we categorized the former as full thickness cutaneous flap to prevent the confusion of terminology. From the clinical aspects, perforating vessels that construct the vascular pedicles were categorized into 6 types based on the vascular pattern from the source vessel to the dermal plexus. These six types of perforating vessels can be simplified as follows: 1) direct cutaneous vessels, 2) accompanying vessels, 3) muscular artery perforators, 4) septal perforators.