[Posterior interosseous free flap because of absence of posterior interossous pedicle. A report of an individualised salvage procedure and of an exceptional anatomical variation. Review of the literature].

The posterior interosseous flap on the posterolateral aspect of the forearm is appreciated for its thinness and the length of its vascular pedicle. Arterial supply to the flap comes from the posterior interosseous artery, which gives off several cutaneous branches. This flap is most often used with its distal pedicle as its artery presents anastomoses with the anterior interosseous artery and the dorsal arterial carpal network. However, its dissection is often difficult because of anatomical variants and is not reliable in case of traumatic history at the distal forearm. A case is reported where no posterior interosseous pedicle was found and the flap was subsequently transferred as a free flap supplied by a perforating branch arising from the anterior interosseous artery.