The author presents his experience with the posterior interosseous free flap for hand resurfacing over a 2-year period. Nine flaps were transferred to the hand for eight traumatic defects and one case of radiation-induced fibrosis/contracture. The flap is carefully defined along the posterior interosseous/recurrent anterior interosseous vascular axis. Vascular diagrams very thoroughly depict the available source vessels and the possible flap variations that result. A distally extended skin and fascia island is described and was utilized in each case, allowing for a long vascular pedicle of up to 9 cm for anastomosis. Skin islands ranging from 8x3 cm to 12x5 cm were used with primary donor site closure achieved in every case. The primary use for this flap in this series was for release and resurfacing of contracted first web spaces in 8/9 cases. All arterial anastomoses were performed in an end-to-side fashion to the radial artery, and flap monitoring was performed with an 8 MHz Doppler probe every hour for three days. The patients were maintained on anticoagulation with intravenous Dextran for 5 days and aspirin for one month. All flap transfers were successful.
The posterior interosseous pedicled flap has been well described since the mid-1980’s and has been used primarily as a distally-based, reverse-flow flap for hand coverage. In instances where a thin fasciocutaneous flap is needed for hand coverage and associated forearm soft-tissue or vascular injury makes pedicled flap transfer untenable, this flap can be transferred, either from the ipsiliateral or the contralateral forearm, as a free microvascular transfer. The author describes a modification of the usual mid- or proximal-forearm skin island to allow for longer pedicle length to aid in insetting and a microvascular anastomosis at a more proximal level to larger and more reliable vessels than can be found at the recipient site in the hand. This flap has the advantages of thin, pliable soft tissue; ease of dissection; primary donor site closure; a long vascular pedicle (as opposed to the lateral arm fasciocutaneous flap); the availability of sensory innervation through the posterior cutaneous nerve of the forearm; a multiplicity of venous drainage sources for anastomosis; and a vascular axis that will also allow a flow-through configuration for simultaneous revascularization and soft-tissue coverage. Disadvantages include a very visible donor scar; limited size; and smallish, thin-walled vessels which provide some technical challenges in performing microvascular transfer. This paper clearly illustrates at least one application of this versatile fasciocutaneous flap and its reliability and safety when carefully applied.