Microvascular free posterior interosseous flap and a comparison with the pedicled posterior interosseous flap

The posterior interosseous flap has been used as a pedicled flap for coverage of hand wounds. However, the pedicled flap is associated with partial or even complete loss when there is venous congestion. This happens because it depends on retrograde venous drainage. Another pitfall of the pedicled posterior interosseous flap is the undetected damage to the communicating vessels between the anterior and posterior interosseous arteries before surgery. This would result in failure if the flap is used as a distally based flap. Thirty-four patients had been reconstructed with the microvascular free posterior interosseous flap. The free flap has a large draining vein. Flap survival rate was 97%. There was no venous congestion and no partial loss of the flap. It is thin, sensate, and reliable. The free posterior interosseous flap is indicated for coverage of the following wounds: (1) first web space and thumb, (2) radial side of the index and ulnar side of the small finger if a cross-finger flap cannot be used, and (3) defects at the dorsum of multiple fingers. It can also be used as a free fascial flap. The free posterior interosseous flap provides a reliable option for coverage of hand wounds. Previously, another 14 patients with hand wounds had been reconstructed with a pedicled posterior interosseous flap. The results of pedicled and free posterior interosseous flaps are compared.