Objectives: To review a series of consecutives cases where a new forearm flap variation, the Transverse Ulnar Artery Forearm Flap (TUAFF) was used to reconstruct different recipient sites based on the specific requirement for a small flap (5cm by 8 cm or less) composed of thin hairless skin accompanied by a long pedicle. Forearm flaps have been workhorses for microsurgical transfer; the radial forearm flap has been widely preferred over the ulnar forearm flap in general. Recent studies have clarified the benefits of the ulnar forearm flap: thin hairless skin with a donor site on the much-less-visible ulnar border of the arm. The TUAFF can provide the ideal aforementioned characteristics while allowing primary donor site closure with a radial based fasciocutaneous flap leaving the scar burden centered on the less-objectionable ulnar forearm border.

Methods: A single-surgeon series of five consecutive cases, where all patients were given the option of a radial or ulnar flap and resulting scars were discussed. All patients selected the TUAFF based on preferences regarding final scars.  Recipient sites included orbit, palate, foot and heel defects.

The TUAFF is designed with its long axis transverse and distal margin parallel with a wrist flexion crease. The maximal size harvested in this study was 5cm by 8 cm. An incision is made in a proximal direction from the proximal-ulnar corner of the flap along the ulnar aspect of the forearm the length of the expected pedicle required. At this point a back cut is performed on the proximal forearm to the location of the radial artery (Figure 1). The ulnar forearm flap is raised. The skin between the ulnar incision and radial artery/septum is raised as a fasciocutaneous flap. The wrist is flexed no more than 30 degrees and the donor site closed transversely. The proximal aspect of the forearm is closed in a V-Y fashion and any dog-ear tailored. A dorsal splint is applied with the wrist in 30 degrees flexion and the metacarpalophalangeal joint at 70 degrees flexion for two weeks.

Results: All ulnar free flaps and all radially-based fasciocutaneous flaps survived completely. One patient suffered from a wide scar at the Y junction in the proximal forearm that was revised at the patient's request. Two-point fingertip discrimination was within 1mm of the opposite hand in all patients. No ischemic hand complications occurred. No patient required the assistance of a therapist to recover full wrist motion by 8 weeks; all used self-directed range of motion exercises at home monitored by the surgeon.

Conclusion: The TUAFF is a synthesis of variations of previously described techniques and has specific indications and particular advantages. A small patch of thin, supple, hairless skin with a maximal pedicle length is particularly useful in orbital reconstruction and palatal surgery where thick or hairy skin can result in microsurgical success and reconstructive failure.  Another indication is that the TUAFF may be harvested with vascularized periosteum in an effort to support non-vascularized bone grafts.

Picture 1. Diabetic foot ulcer reconstructed with a TUAFF.