The Keystone Design Perforator Island Flap in reconstructive surgery

A surgical technique for closing skin defects following skin cancer (particularly melanoma) removal is described in the present paper. Its use is illustrated in five patients. The technique has been used in 300 cases over the past 7 years and is suitable for all areas of the body from scalp to foot. We have coined the term Keystone Design Perforator Island Flap (KDPIF) because of its curvilinear shaped trapezoidal design borrowed from architectural terminology. It is essentially elliptical in shape with its long axis adjacent to the long axis of the defect. The flap is based on randomly located vascular perforators. The wound is closed directly, the mid-line area is the line of maximum tension and by V-Y advancement of each end of the flap, the 'islanded' flap fills the defect. This allows the secondary defect on the opposite side to be closed, exploiting the mobility of the adjacent surrounding tissue. The importance of blunt dissection is emphasized in raising these perforator island flaps as it preserves the vascular integrity of the musculocutaneous and fasciocutaneous perforators together with venous and neural connections. The keystone flap minimizes the need for skin grafting in the majority of cases and produces excellent aesthetic results. Four types of flaps are described: Type I (direct closure), Type II (with or without grafting), Type III (employs a double island flap technique), and Type IV (involves rotation and advancement with or without grafting). The patient is almost pain free in the postoperative phase. Early mobilization is possible, allowing this technique to be used in short stay patients.

In a series of 300 patients with flaps situated over the extremities, trunk and facial region, primary wound healing was achieved in 99.6% with one out of 300 developing partial necrosis of the flap.

The technique described in the present article offers a simple and effective method of wound closure in situations that would otherwise have required complex flap closure or skin grafting particularly for melanoma.