Objective To discuss the reason of skin flap necrosis caused by vascular crisis of reverse island flap of forearm posterior interosseous artery.Methods Eight-six patients who were underwent reverse island flap of forearm interosseous posterior artery for deep tissues and skin defect on the back of hand between March,2002 and April,2014 were analyzed in this study.Eleven patients had occurred skin flap necrosis,include 5 cases had completely flap necrosis caused by circulation crisis,and 6 cases had partial necrosis at the distal of the flap.Among the necrosis cases,5 cases were injured by the machine injury,4 cases by the heavy crush and 2 cases by the traffic accident.The cause of circulation crisis was analyzed.Results In the series,75 skin flaps survived completely and 11 cases had occurred necrosis,included completely necrosis with 5 cases.The reasons of flap crisis were as follows:for the completely necrosis,2 cases with variation of perforating branch of posterior interosseous artery,1 case with absence of posterior interosseous artery,1 case with vessel pedicel entrapment in subcutaneous tunnel,and 1 case with misconduct venous congestion caused by the reverse perfusion of superficial vein.The reason of circulation crisis of completely necrosis were as follows:2 cases with artery crisis and 3 of them with distortion of entrapment at pedicel and vein crisis.One case was cured through debridement,change of medical prescription and skin grafting;and 4 cases were cured with other flap repair technique.For the partial necrosis,2 cases with variation of perforating branch of posterior interosseous artery,1 case with excessively narrow entrapment at pedicel in subcutaneous tunnel,1 case with folding vessel pedicel entrapment of skin at the back of wrist,1 case with misconduct of superficial vein trunk and 1 case with intraoperative side-injury.The symptoms of circulation crisis of completely necrosis were as follows:2 cases with artery crisis and 4 of them with distortion of entrapment at pedicel and vein crisis.Four cases were cured through debridement and skin grafting,1 case was cured by the vacuum-sealing drainage (VSD) and 1 case with skin flap repair at pedicle of abdomen.Conclusion The anatomic variation of perforator vessel of reverse island flap of forearm posterior interosseous artery;narrow entrapment at pedicel in subcutaneous tunnel and distortion of entrapment at pedicel;venous congestion caused by the reverse perfusion of superficial vein;intraoperative side-injury of the pedicel of the flap;excessively folding vessel pedicel entrapment of skin at the back of wrist after surgery will cause the circulation crisis of reverse island flap of forearm posterior interosseous artery and induce the necrosis of the skin flap.

Objective To observe the effects of different ligation sites and fasting method on a C57BL/6J mouse model of partial bile duct ligation(pBDL)-induced cholestasis,to establish a pBDL modeling method with a high modeling rate,typical symptoms,and good stability.Methods C57BL/6J mice were subjected to selective ligation of the left hepatic bile duct(L-pBDL)and left-to-median bile duct junction ligation(ML-pBDL)for modeling,and the effects of different pBDL ligation method on serum alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase(ALP),total bilirubin,total bile acid,and liver histopathology were observed.The effects of different fasting method on symptoms and liver injury in the ML-pBDL model were also observed after fasting for 12 and 16 h before surgery,and for 4 h after surgery.Results(1)The incidence of jaundice in the ML-pBDL group was 52.94%and the survival rate within 3 weeks after surgery was 64.71%,while the incidence of jaundice in the L-pBDL group was 11.76%and the survival rate within 3 weeks after surgery was 82.35%.Compared with those in the sham surgery group,serum liver function indicators were significantly increased in the L-pBDL and ML-pBDL groups(P＜0.01),and ALP activity was significantly higher in the ML-pBDL group than in the L-pBDL group(P＜0.05).Compared with mice in the L-pBDL group,mice in the ML-pBDL group had more severe liver fibrosis at 3 weeks post-surgery(P＜0.01).(2)In addition,the incidence of jaundice in the 16 h fasting group was 93.33%and the survival rate within 3 weeks after surgery was 73.77%,while the incidence of jaundice in the 12 h fasting group was 42.86%and the survival rate within 3 weeks after surgery was 71.42%.Compared with those in the normal group,ALP activity,alanine aminotransferase/aspartate aminotransferase ratio,total bile acid level,and proportion of collagen fiber area were all significantly increased in the 16 h and 12 h fasting groups(P＜0.05).Although the observed indicators were higher in the 16 h fasting group compared with those in the 12 h fasting group,the difference was not significant(P＞0.05).Mice in the 12 h and 16 h fasting groups both showed significant bile duct hyperplasia and liver fibrosis(P＜0.01),with more severe liver fibrosis in the 16 h fasting group(P＜0.01).Conclusions Both L-pBDL and ML-pBDL ligation method can be used to establish a mouse model of cholestasis;however,symptoms in the L-pBDL model only exhibit transient damage characteristics,while the liver lesions in the ML-pBDL model are typical and stable.Prolonging the preoperative fasting time can improve the modeling rate and stability of the ML-pBDL model and produce more-typical pathological symptoms.