Abstract： Objective To explore the effect of intraoperative blood transfusion volume on postoperative coagulation function of thoracic spine tuberculosis,and to identify their correlation.Methods A total of 51 patients undergoing thoracic spine tuberculosis with an anterior approach who were admitted to the First Department of Orthopedics of Hebei Chest Hospital from May 2020 to October 2022 were screened for a retrospective analysis.Patients were divided into three groups according to the amount of intraoperative blood transfusion:Group A(≤400mL,19 cases),group B(400-800mL,23 cases),and group C(＞800mL,9 cases).Venous blood was collected for routine blood test,coagulation function and thrombelastogram before surgery(T0),1 day after surgery(T2),and 7 days after surgery(T3).Analysis of variance was performed on platelets(PLT),prothrombin time(PT),international normalized ratio(INR),R value,K value,MA value and α angle,followed by the least significant difference(LSD)test on valid parameters to compare the significance and correlation.Results Significantly decreased R value and K value,and increased α angle,MA value and PLT in the three groups after surgery indicated a hypercoagulable state of blood.At T1,there were significant differences in the pairwise comparisons of the R-value,α angle,MA value and PLT(P＜0.05).At T2,there were significant differences in the MA value and PLT among the three groups(P＜0.05).At T1,there were significant differences in the pairwise comparisons of MA and PLT(P＜0.05).At T2,there was a significant difference in the MA between group A and B(P=0.047).At T2,there were significant differences in the PLT and MA between group A and C(P＜0.05).At Tl,the blood transfusion volume was significantly correlated with PLT,R value,MA value and α angle(P＜0.05).PLT,MA value,and α angle were positively correlated with the amount of blood transfusion,and R value was negatively correlated with the amount of blood transfusion(Rs=-0.371).At T2,PLT and MA were positively correlated with blood transfusion volume.Conclusion Postoperative coagulation function is in a hypercoagulable state in thoracic spine tuberculosis patients.PLT,R value,MA value and α angle are correlated with intraoperative blood transfusion volume.The amount of intraoperative blood transfusion is positively correlated with postoperative hypercoagulability.The more intraoperative blood transfusions,the higher the risk of postoperative thrombosis.