Objective To investigate the anatomic foundation of using main branch of posterior femoral nerve to restore the sensation function of distal basedsural island flap. Methods Thirty cases of adult human cadaver legs fixed by 4%formaldehyde were used. Anatomical investigation of the posterior femoral nerves of lower legs was conducted under surgical microscope to observe their distribution, branches and their relationship with small saphenous vein. Nerve brancheswith diameter more than 0.1 mm were dissected and accounted during observation.The length and diameter of the nerves were measured. Results The main branch of posterior femoral nerve ran downwards from popliteal fossa within superficial fascia along with small saphenous vein. 70% of the main branch of the posterior femoral nerves lay medially to small saphenous vein, and 30% laterally. They wereclassified into 3 types according to their distribution in lower legs: typeⅠ (33.3%) innervated the upper 1/4 region of lower leg (region Ⅰ), type Ⅱ (43.3%) had branches in upper 1/2 region (region Ⅰ and Ⅱ), and type Ⅲ (23.3%) distributed over the upper 3/4 region (region Ⅰ, Ⅱ and Ⅲ). In type Ⅱ, the diameter of the main branches of posterior femoral nerves in the middle of popliteal tossa was 10±04 mm and innervated the posterior upper-middle region (which was the ordirary donor region of distal based sural island flaps) of lower legs with 2.0±0.8 branches, whose diameter was 0.3±0.2 mm and length was 3.5±2.7 mm. The distance between the end of these branches and small saphenous vein was 0.8±0.6 mm. In type Ⅲ, their diameter was 1.2±0.3 mm and innervated the posterior upper-middle region of lower legs with 3.7±1.7 branches, whose diameter was 0.4±0.1 mm and length was 3.7±2.6 mm. The distancebetween the end of these branches and small saphenous vein was 0.8±0.4 mm. Conclusion 66.6% of human main branch of posteriorfemoral nerves (type Ⅱ and type Ⅲ) can be used to restore the sensation of distal based sural island flap through anastomosis with sensor nerve stump of footduring operation.
Objective To explore the clinical effect of the lower rotating point super sural neurocutaneous vascular flap on the repair of the softtissue defects in the ankle and foot. Methods From May 2001 to February 2006, 24 patients with the soft tissue defects in the ankle and foot were treated with the lower rotating point super sural neurocutaneous vascular flaps. Among the patients, 15 had an injury in a traffic accident, 6 were wringedand rolled by a machine, 1 was frostbited in both feet, 2 were burned, 25 had an exposure of the bone and joint. The disease course varied from 3 days to 22 months; 19 patients began their treatment 3-7 days after the injury and 5 patients were treated by an elective operation. The soft tissue defects ranged in area from 22 cm × 12 cm to 28 cm × 12 cm. The flaps ranged in size from 24 cm × 14cm to 30 cm × 14 cm, with a range up to the lower region of the popliteal fossa. The rotating point of the flap could be taken in the region 1-5 cm above thelateral malleolar. The donor site was covered by an intermediate thickness skingraft. Results All the 25 flaps in 24 patients survived with asatisfactory appearance and a good function. The distal skin necrosis occurred in 1 flap, but healing occurred after debridement and intermediate thickness skin grafting. The follow-up for 3 months to 5 years revealed that the patients had a normal gait, the flaps had a good sense and a resistance to wearing, and no ulcer occurred. The two point discrimination of the flap was 5-10 mm. Conclusion The lower rotating point super sural neurocutaneous vascular flap has a good skin quality, a high survival rate, and a large donor skin area. The grafting is easy, without any sacrifice of the major blood vessel; therefore, it is a good donor flap in repairing a large soft tissue defect in the ankle and foot.
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.
Objective To investigate the clinical efficiency of thedistally based sural island flap and myofasciocutaneous flap in reconstruction of defect and osteomyelitic cavity of the ankle and foot. Methods From June 1997 to October 2004, 21 patients with soft tissue defects and osteomyelitis in the ankle and foot were treated with the distally based sural island flap and myofasciocutaneous flap. There were 20 males and 1 female aging from 6 to 78 years. The defect was caused by soft tissue defect trauma(18 cases) and electrical injury ( 3 cases). Among 21 patients, 17 were treated with island flaps, 4 by the myofasciocutaneous flap. The size of flaps ranged from 4 cm×5cm to 16 cm×22 cm. The donorsites were closed directly in 4 cases. Results The flaps completely survived in 21 cases and healing by first intention was achieved. After a follow-up of 36 months, no complication occurred. The color and texture of the flaps were good. The appearance and the function were satisfactory. Conclusion Distally basedsural flap is a reliable flap. This flap has rich blood supply without sacrifice of major arteries. Flap elevation is easy. It is very useful in repairing large soft tissue defects of the lower leg, the ankle and the foot, especially inrepairing deep soft tissue defects and osteomyelitic cavities .
OBJECTIVE: To sum up the application experience of the sural nerve island flap pedicled with the collateral vessels. METHODS: From 1997, the retrograde-flow sural nerve island flaps pedicled with collateral vessels were performed to repair the soft tissues defects of the shank in 3 cases, ankle in 3 cases and foot in 8 cases. RESULTS: Twelve flaps were survived, one flap was partially necrosed and one flap was necrosed. Among them, 10 wounds healed by first intention, 3 cases were healed after changing dressing and the one necrosed flap was repaired by free flap transplantation. Nine cases were followed up for 3 to 21 months and had fine appearance and function. The flap texture was similar to normal skin, the sensation of flap partially recovered after 6 months. CONCLUSION: The flap has more reliable blood supply and great rotation arc, it is easy to resect with little injury. It is excellent for repairing the soft tissues defect in the anterior leg, ankle and proximal half of foot. It is more significant while the main blood vessels are damaged.