Objective To investigate the effects of changing the arteriovenous pressure difference on the survival area of reverse island flap in New Zealand white rabbits models.Methods The saphenous artery and saphenous vein of New Zealand rabbits were selected to design experimental models of reverse island flap.Experi mental rabbits were randomly divided into 4 groups:group A:control group (reserved pedicle integrity of superficial veins);group B:part anastomosis of saphenous artery group (the distal saphenous artery of the flap was cut,then trimmed its original diameter to half and done end-to-end anastomosis);group C:part anastomosis of vein group (distal superficial veins was cut,then trimmed its original diameter to half and done end-to-end anastomosis);group D:ligated superficial veins group (pedicle superficial veins was ligated).After surgery,the flaps were measured by general observation.Blood distribution at different times of the flaps was detected by radionuclide scans.Survival area of the flap was measured to compare the survival rate of flap.Distribution of blood vessels and the state of blood cells were observed by Histological examination.Results The flap survival rate was (82.27-± 11.71)％ in group B,showing significant differences when compared with that group A (47.70-± 11.18)％,group C (47.70 ± 11.18)％ and group D (47.70 ± 11.18)％ (P ＜ 0.05).Radionuclide scans showed that the radioactive material in group B could be seen clearly,the radioactive material in groups A,C and D were a transient existence.Ten days postoperatively,histological observation showed that group B had more capillary regeneration and blood cells remain compared with other groups.Conclusion Increase the blood supply can increase the survival area of the reverse island flap,and simply promote the venous drainage can not effectively improve the survival rate of the flap.

Objective:To explore clinical application of the island flap pedicled of the descending branch of perforating branch from lateral anterior malleolus of peroneal artery in repairing the soft tissue defects in midfoot and forefoot.Methods:From January, 2010 to December, 2016, based on the anastomosis between the descending branch from a terminal branch of peroneal artery on the anterior aspect of the lateral malleolus and other branches located around the ankle joint and sinus tarsi, island flap with a pedicle could be harvested more distally and to be used in covering the soft tissue defects in midfoot and forefoot of 5 patients. Sizes of the flap were from 15 cm×12 cm to 8 cm×6 cm. All patients were followed-up in outpatient clinic or through WeChat. The appearance of the flaps and ankle function were recorded simultaneously.Results:All flaps were survived without any secondary surgeries. During the follow-up of 6-15 months, the texture of flaps was good with satisfactory estheticity. Range of motion at the injured ankle was 15° in dorsi flexion and 25° in plantar flexion.Conclusion:The flap with a pedicle of the descending branch of perforating branch from lateral anterior malleolus of peroneal artery is good enough to be used in the reconstruction of soft tissue defects in midfoot and forefoot.