BACKGROUND:Deep vein thrombosis is a common complication following bone surgeries,so its prevention and treatment become critical.However,there are few studies on the incidence of deep vein thrombosis after spine surgery in the elderly.OBJECTIVE:To explore the diagnosis of deep vein thrombosis after spine surgery in the elderly and its incidence after intervention with low-molecular-weight heparin.METHODS:All patients undergoing spine surgery were randomly divided into experimental and control groups.Patients in the experimental group were subjected to the subcutaneous injection of 0.4 mL of low-molecular-weight heparin (4 100 IU) at 12 hours postoperatively,once daily for 7-14 days from the next day.Those received no intervention served as controls.The thromboplastin time,thrombin time,activated partial thromboplastin time,and level of plasma fibrinogen were detected before and after treatment.Color Doppler ultrasound results of the lower extremity vessel before and after treatment and postoperative drainage volume were recorded.RESULTS AND CONCLUSION:(1) In the experimental group,the lower level of plasma fibrinogen and slightly prolonged thromboplastin time,thrombin time and activated partial thromboplastin time were observed,but all were within the normal range.(2) The incidence of deep vein thrombosis in the experimental group (0％) was significantly lower than that in the control group (5％,P ＜ 0.05).(3) To conclude,low-molecular-weight heparin therapy significantly reduced the incidence of deep vein thrombosis after spine surgery.