Objective To evaluate the effect of open bone grafting combined with negative pressure closed drainage technology on post-traumatic infectious bone defect.Methods A total of 92 patients with post-traumatic infectious bone defects admitted to Zaozhuang Municipal Hospital from September 2020 to September 2021 were selected as the research objects,they were divided into bone graft group and drainage group according to the lottery method,with 46 cases in each group,the bone graft group was treated with open bone grafting,and the drainage group was treated with negative pressure closed drainage.Detect inflammatory indicators,observe the function and recovery of bone and joints,and calculate the validity of two groups.Results There were no significant differences in C-reactive protein(CRP)and white blood cell(WBC)between the two groups before treatment(P>0.05).After treatment,CRP and WBC of the two groups were lower than those before treatment,and the CRP and WBC of drainage group were lower than those of the bone graft group,the differences were statistically significant(P<0.05).Before treatment,there were no significant differences in Hospital for Special Surgery(HSS)score and visual analogue scale(VAS)between the two groups(P>0.05).After treatment,the HSS score in the drainage group was higher than that in the bone graft group,and the VAS score in the drainage group was lower than that in the bone graft group,the differences were statistically significant(P<0.05).The recovery time and hospital stay of the patients with bone defects in the drainage group were shorter than those in the bone graft group,and the differences were statistically significant(P<0.05).The treatment effect in the drainage group was higher than that in the bone graft group,and the difference was statistically significant(P<0.05).Conclusion Open bone grafting combined with negative pressure closed drainage can improve the treatment effectiveness,reduce inflammation,enhance bone and joint function,and promote the prognosis of patients with bone defects.