Abstract: Objective　To repair the dorsal wound by increasing the propulsion distance of the dorsal flap through the multi-grade effect of the ductility of the skin, the slip between the subcutaneous superficial fascia and the skin, the angular displacement of the dorsal branch from the proper digital artery and the elasticity of the proper digital artery.　Methods　The skin flaps of 34 fingers on 11 sides of fresh adult cadaveric hands were designed on the dorsal side of the middle and proximal segments of the finger respectively. The contents of the flap included the dorsal skin, the subcutaneous superficial fascia, the proper digital artery on one side of the finger and the dorsal branch of the proper digital artery. When the flap was pushed to the distal end of the finger, the ductility of the skin，the sliding of the subcutaneous superficial fascia,the angular displacement of the dorsal branch of the proper digital artery and the elasticity of the proper digital artery all played a certain role in the advancement of the dorsal finger flap respectively, the advancement distance of the flap can be increased by the multi-grade superposition of these four effects.　Results　The maximum propulsion distance of the dorsal flap simulated on the fresh specimens was 2.4 cm and the dorsal flap in the proximal segment of finger was 4.5 cm.　Conclusions　The advancing distance of the dorsal multi-grade advanced flap increases significantly. The maximum advancing distance is 4.5cm and the average distance is 2.5cm. The operation of the multistage advancing dorsal finger flap is safe and simple, it is one of the ideal flap for repairing small and medium-sized wounds of the dorsal finger.

Key words: Dorsal finger skin defect, 　Repair,  ,  ,  , Proper digital artery, 　Advancement flap