THE ANATOMIC BASIS FOR ARTERIOVENOUS SHUNTING IN HUMAN LOWER LEG FASCIAL FLAPS

Clinical experience has suggested that arteriovenous shunting may occu r in fascial flaps. The anatomic basis for this has not been fully est ablished. The aim of this study was to determine the size, location, a nd nature of arteriovenous shunts in human lower leg deep fascia. Deep fascia was harvested from the limbs of nine embalmed cadavers. Small pieces of fascial tissue were studied with the aid of three staining t echniques (methylene blue, oil red-O triethyl phosphate, and Gomori's rapid one-stage trichrome technique), which were used to enable the mi crovascular anatomy to be visualized more clearly. Arteriovenous anast omoses proximal to the capillary bed and with an external diameter gre ater than 50 mu m were identified in the suprafascial, subfascial, and intrafascial plexuses but were not found to be a common feature of th e microvascular anatomy. Thoroughfare channels within the capillary be d and with an external diameter ranging from 12 to 25 mu m were freque ntly identified in all three levels of the fascial plexus. The results of this study establish an anatomic basis for arteriovenous shunting in fascial flaps.