Objective To investigate the origin of small saphenous vein of distally-based of sural nerve nutrient vessels flap and its clinical application. Methods The origins of nutrient vessels of small saphenousvein and communicating branches of superficial-deep vein were observed on specimens of 30 adult cadaveric low limbs by perfusing red gelatin to dissect the artery. Results The nutrient vessels of small saphenous vein originated from the heel lateral artery, the terminal perforator branches of peroneal artery and intermuscular septum perforating branches of peroneal artery. There were 2 to 5 branches ofsuch distally-based perforating branches whose diameters ranged from 0.6 to 1.0 mm. Those perforating branches included fascia branches, cutaneous branches nerve and vein nutrient branches. Those nutrient vessels formed a longitudinalvessel chain of sural nerve shaft, vessel chain of vein side and vessel networkof deep superficial fascia. The small saphenous vein had 1 to 2 communicating branches of superficial-deep vein whose diameter was 1.7±0.5 mm， 3.4±0.9 cm to the level of cusp of lateral malleolus, and converged into the fibular vein. Conclusion Distally-based sural nerve, small saphenous vein, and nutrient vessles of fascia skin have the same region. The communicating branches of superficial-deep vein is 3 to 4 cm to the level of cusp lateral malleolus. These communicating branches could improve the venousdrainage of the flap.
Objective To investigate the distribution of the perforating branches artery of distally-based flap of sural nerve nutrient vessels and its clinical application. Methods The origins and distribution of perforating branchesartery of distally-based flap were observed on specimens of 30 adult cadavericlow limbs by perfusing red gelatin to dissect the artery.Among the 36 cases, there were 21 males, 15 females. Their ages ranged from 6 to 66, 35.2 in average. The defect area was 3.5 cm×2.5 cm to 17.0 cm×11.0 cm. The flap taken ranged from 4 cm×3 cm to 18 cm×12 cm. Results The perforating branches artery of distally-based flap had 2 to 5 branches and originated from the heel lateral artery, the terminal perforating branches of peroneal artery(diameters were 0.6±0.2 mm and 0.8±0.2 mm, 1.0±1.3 cm and 2.8±1.0 cm to the level of cusp lateral malleolus cusp).The intermuscular septum perforating branches of peroneal artery had 0 to 3 branches. Their rate of presence was 96.7%,66.7% and 20.0% respectively(the diameters were 0.9±0.3, 1.0±0.2 and 0.8±0.4 mm, andtheir distances to the level of cusp of lateral malleolus were 5.3±2.1, 6.8±2.8 and 7.0±4.0 cm). Those perforating branches included fascia branches, cutaneous branches, nerve and vein nutrient branches. Those nutrient vessels formed longitudinal vessel chain of sural nerve shaft, vessel chain of vein side and vessel network of deep superficial fascia. The distally-based superficial sural artery island flap was used in 18 cases, all flaps survived. Conclusion Distally-based sural nerve, small saphenous vein, and nutrient vessels of fascia skin have the same origin. Rotation point of flap is 3.0 cm to the cusp of lateral malleolus, when the distally-based flap is pedicled with the terminal branch of peroneal artery.Rotation point of flap is close to the cusp of lateral malleolus, when the distally-based flap is pedicled with the heel lateral artery.