Abstract: Objective　To explore the application and clinical effect of keystone perforator flap in repairing soft-tissue defect of hand and foot. Methods　From February 2015 to December 2020, a total of 24 patients (14 males and 10 females) with soft tissue defects in the hand and foot were repaired by the keystone perforator flaps. Of these, 18 had hand defects (13 palmar and 5 dorsal) and 6 had foot defects (3 plantar and 3 dorsal). The defects were located at the joint site in 7 cases. The defect area ranged from 1.0 cm×1.5 cm to 3.0 cm×5.5 cm, and the flap harvesting area ranged from 1.0 cm×2.0 cm to 4.5 cm×8.0 cm. Selective fixation was performed for 2 to 3 weeks according to the defect site and area after surgery. Results　All patients were followed up for 13 months on average (6-24 months). All incisions healed by first intention. The surface of the flap was smooth and there was no color difference with the surrounding skin. The flap showed sensitivity to touch, good functional recovery, and high patient satisfaction. Conclusion　Keystone perforator flap is a reliable method for repairing soft tissue defects in the hand and foot, which not only has few complications but also can meet the appearance and functional needs.

Key words: Keystone flap, 　Hand function, 　Soft tissue defect, 　Wound repair, 　Microsurgical technique