Fig. 1

The anatomy of the dorsal perforators of the digital artery: a showing that four dorsal perforators arise from the radial digital artery (P1 to P4), and the vessel chains are faintly visible between the perforators. A dorsal perforator arises from the ulnar digital artery. b Two dorsal perforators arise from the ulnar proper artery of the thumb (P1, P2), and the vessel chain is visible between the perforators. c A simulated surgery was performed on the specimen, and the flap was designed slightly on the dorsal radial aspect of the interphalangeal joint, the proximal phalange, and the distal end of the first metacarpal bone of the thumb. d Through a volar incision, two dorsal perforators (P1, P2) of the radial digital artery into the flap and the vessel chain between them can be visualized. e The flap was dissected until only a distal perforator (P1) was connected to the finger. f The flap is rotated approximately 160° along the distal perforator as the pedicle to cover the defect