The authors reviewed 11 cases of finger defects treated with heterodigital artery skin flaps extended to non-adjacent digits by division of a dominant dorsal vein and re-anastomosis following transfer. The flaps ranged in size from 2 x 2 to 5.5 x 3 cm and were used to treat finger defects from infection, trauma, amputation with partial digital loss, and chemical burn. The design of the flaps was according to a standard skin and subcutaneous heterodigital artery transposition flap, without inclusion of the underlying donor digital nerve. The arterial pedicles were extended, where necessary, by division of the adjacent proper digital artery from the common digital artery to the flap, moving the axis of rotation proximally to the superficial arch. The authors emphasize the importance of performing a digital Allen's test and a pre-division microvascular clamp test to determine the viability of the adjacent finger prior to division of its digital artery.
All of the flaps healed without tissue loss or complications. The donor sites were also free of complications, with good or excellent functional preservation. One would like to see more objective characterization of the results, such as range of motion, 2-pt. discrimination, and pulp-to-pulp pinch strength to support their conclusions. This is not a new procedure, but rather a report of several cases illustrating a modification of an existing procedure, the heterodigital island flap, which allows for increased flexibility in designing the flap. However, the need for microsurgical anastomosis, hospitalization with anticoagulation, a donor defect of similar size and potential morbidity from an adjacent uninjured digit make the use of this flap less trouble-free.
Dorsal metacarpal artery transposition flaps can offer similar coverage without the need for vein division and re-anastomosis. However they cannot replace glabrous palmar finger skin, making them a less attractive option. Other free tissue transfers are also limited in their ability to transfer like tissue. The first webspace/partial toe pulp flap from the foot does, however, bring very similar tissue to the finger, with even larger dimensions possible. And the need for only one additional anastomosis may make it a more attractive option for some surgeons who wish to limit the amount of morbidity to the already injured hand. As always, one must consider all of these factors when deciding on reconstructive options to best suit any given defect. The authors do a good job of describing a procedure which, in their hands, extends the utility of an already reliable reconstructive option for isolated defects of the fingers with limited total surface area.