[Defect coverage of the hand using a rare Siamese combined flap].

We report 2 cases of extensive soft tissue defects simultaneously affecting the palm and dorsum of the hand. The defect was covered with a Siamese flap combination consisting of a free, distally extended lateral upper arm flap with microvascular anastomosis, and a posterior interosseous artery flap. We discuss possible indications, the operative technique and advantages versus disadvantages of this rarely applied flap combination.