Keystone island flap: an alternative reconstructive option to free flaps in irradiated tissue

The Keystone Flap is an island flap that is very useful for repairing skin defects of the integument. Described as a keystone, this arc-shaped flap in fact consists of a schematically designed, perforator-based reconstructive unit which serendipitously resembles two conjoined VY flaps. This facilitates closure because of the multiple VY points at the extremes, where the surrounding tissue is advanced to close the defect while the flap size remains basically static.

A consecutive series of nine cases involving the head and neck and inguinal regions were examined to show the use of the Keystone Flap in irradiated tissue for recurrent disease. They are described by using a combination of clinical illustrations and diagrams to explain the surgical technique.

The average age of the patients in the series is 74 years. A low complication rate and rapid wound healing with no significant flap necrosis was shown in this series. Additionally the short operation time is quite beneficial, particularly for the elderly.

There is a low complication rate using Keystone flaps (this double VY is a clinical development from Diffenbach's original work of 1848(1)) and this technique is particularly useful in achieving wound healing especially after irradiation treatment. This surgical technique once mastered is easy to perform. Another bonus is that there is minimal use of postoperative analgesia. Additional XRT is well tolerated by the patients with minimal evidence of wound complications, while achieving an acceptable aesthetic appearance.