ABSTRACT
Objective Through investigating the anatomical features of the perforator from the ulnar palmar digital artery of the little finger and the dorsal descending branch of the ulnar artery,to establish a new approach for the reconstruction of sofi tissue defect of the ulnar palm and the little finger.Methods The fifth caput metacarpale was taken as the observation points on 30 specimens of adult human upper limb perfused with red latex.Something as follows were observed under surgery magnifier:①The origin,external diameter,branches,distribution and the backbone length of the perforator of the ulnar palmar digital artery of the little finger;the distance from the fifth caput metacarpale to the perforate artery ; ② The route and distribution of the dorsal descending branch of the ulnar artery.Mimic operation was performed on another fresh specimen.Results The origin of the ulnar palmar digital artery of the little finger has two different type:93.3％ spring from the external of the arcus volaris superficialis,6.7％ formed by the combination of the third arteriae metacarpeae palmares and the branch from arcus volaris profundus.Although it has two different origins,the perforator has only one piercing point,which located at (1.3 ±0.3)cm upon the fifth caput metacarpale.The perforator,ultimately,combines with the descending branch of the ulnar artery after it pass through the slot between the muscle tendon of hypothenar superficial layer (the flexor digiti minimi brevis and the abductor digiti minimi) and the fifth metacarpale bone.External diameter of the perforator was (0.8 ± 0.4) mm and the backbone length was(2.0 ±0.6)cm.Conclusion The location of the anastomose point between the perforator,which springs from the ulnar palmar digital artery of the little finger,and the dorsal descending branch of the ulnar artery is constant.The perforator flap based on the perforator of ulnar palmar digital artery of the little finger,with sufficient blood supply,can be transferred flexiblely,and can be designed to repaire the defect of soft tissue on the ulnar palm and the little finger.