Objective To determine the risk factors associated with surgical site infection in closed calcaneal fractures.Methods A retrospective analysis was made on the clinical data of 312 patients with closed calcaneal fracture who had been treated by open plate osteosynthesis at our trauma centre from January 2008 to November 2014.They were 182 males and 130 females,from 18 to 75 years of age (average,44.3 years).By Sanders classification,52 cases were type Ⅱ,146 type Ⅲ,and 114 type Ⅳ.The fractures were caused by fall from a height in 159 cases,traffic accident in 97 ones,and crushing in 56 ones.All the patients received open reduction and internal fixation via a typical L-shaped lateral incision.Gender,age,cause for injury,smoking history,diabetes,interval between injury and operation,operation time and bone grafting were analyzed as possible risk factors in the study.Multivariate logistic regression was conducted for significant risk factors derived from the univariate analysis.Results The patients were divided into an infection group (28 cases,9.0％) and a non-infection group (284 cases,91.0％).The univariate analysis showed that the rate of smoking was significantly higher,the operation time significantly longer,the interval between injury and operation significantly shorter in the infection group than in the non-infection group (P ＜ 0.05).However,the logistic regression analysis revealed that operation time was the only independent risk factor for surgical site infection (P =0.005,OR =43.870).Conclusion Since operation time may be an independent risk factor for surgical site infection in closed calcaneal fracture,it is important to speed up surgery as quick as possible in control of surgical site infection as long as the surgical quality is ensured.

Objective　To observe the therapeutic effect of combined use of anti-silicosis drugs on early silicosis of rats. Methods　Male Wistar rats were exposed to lower dose(20 mg/rat) of quartz by intr atracheal injection.In the early stage of silicosis,the experimental rats were t reated with 4 single drugs,i.e. poly-2-vinyl pyridine-nitrogen oxide(PVNO),te trandrine(TD),quinolyl-piperazine hydroxyl phosphate(QOHP),aluminium citrate(AL C ) and 3 combined drugs i.e. PVNO+TD,TD+QOHP,ALC+TD for 2 and 5 months respective ly. Results　The wet and dry weight and collagen content of w hole rat lung in all of treated groups were obviously lower than that of quartz control groups(P<0.05 or P<0.01),but there were no significant d ifferences between the groups of single treatment and the groups of combined tre atment (P>0.05) except some items on 150 d.Evalutaion by RSR showed th at combined use of ALC+QOHP and TD+QOHP for both 60 d and 150 d were much more e fficient than single use of drugs.Treatment with PVNO+TD for 150 d was also bett er than single use.Pathological examination showed that silicotic lesions of rat lung were much lighter in treated groups than that of quartz groups,and also li ghter 1/2～1 grade in combined use groups as compared to single use groups. Conclusion　The therapeutic effects of combined use of anti-s ilicosis drugs on early silicosis were better than those of single drugs.

Objective　To observe the therapeutic effect of combined use of anti-silicosis drugs on early silicosis of rats. Methods　Male Wistar rats were exposed to lower dose(20 mg/rat) of quartz by intr atracheal injection.In the early stage of silicosis,the experimental rats were t reated with 4 single drugs,i.e. poly-2-vinyl pyridine-nitrogen oxide(PVNO),te trandrine(TD),quinolyl-piperazine hydroxyl phosphate(QOHP),aluminium citrate(AL C ) and 3 combined drugs i.e. PVNO+TD,TD+QOHP,ALC+TD for 2 and 5 months respective ly. Results　The wet and dry weight and collagen content of w hole rat lung in all of treated groups were obviously lower than that of quartz control groups(P<0.05 or P<0.01),but there were no significant d ifferences between the groups of single treatment and the groups of combined tre atment (P>0.05) except some items on 150 d.Evalutaion by RSR showed th at combined use of ALC+QOHP and TD+QOHP for both 60 d and 150 d were much more e fficient than single use of drugs.Treatment with PVNO+TD for 150 d was also bett er than single use.Pathological examination showed that silicotic lesions of rat lung were much lighter in treated groups than that of quartz groups,and also li ghter 1/2～1 grade in combined use groups as compared to single use groups. Conclusion　The therapeutic effects of combined use of anti-s ilicosis drugs on early silicosis were better than those of single drugs.