Abstract:

Objective　 To provide anatomic basis for more effectively handling small saphenous vein in the distally based sural neurocutaneous flap in order to alleviate the venous blood regurgitation.　Methods　The small saphenous veins and their tributaries were dissected at the malleolar region of 40 lower extremities of adult cadavers. The line was served as ankle reference line, which passed the tip of the external ankle. The origin patterns of small saphenous vein were observed. The vertical distance between the point of the highest branch jointing small saphenous vein trunck and the ankle reference line was measured.　Results　According to the infusion points and the courses of tributeries, small saphenous veins could be divided into four types: the single trunk type 47.5％（19 cases）, the double trunks type 27.5％（11）, the three trunks type 10.0％（4）, and the four trunks type 15.0％（6）. However, there were three types according to the highest jointing point: the low origin type 10.0％（4）, the average origin type 35.0％（14）, and the high origin type 55.0％（22）.　Conclusions　The origin of small saphenous vein is variable, which implicate that, during the procedure of preparing the distally based sural neurocutaneous flap, not only the small saphenous vein trunks must be ligated, but also the tributeries, which maybe entry the base of flap, need to be handled.

Key words: Flap, Sural nerve, Small saphenous vein, Chronic ulcer, Trauma