Abstract: Objective To study the influence of bleeding after using low molecular weight heparin （LMWH） to prevent deep vein thrombosis (DVT) in patients with thoracolumbar spinal bursting fracture and spinal cord injury operated by rear internal fixation. Methods 120 cases were divided into the observation group (64 cases) and control group (56 cases). The observation group accepted hypodermic injection of LMWH to prevent DVT, while the control group did not. Results The volume of bleeding and blood transfusion, the change of red blood cell count (RBC) and hemoglobin were compared between two groups before and after operation. There is no statistical significance. Conclusion During the period of the operation of rear internal fixation, low molecular weight heparin cannot increase the bleeding and is safe to prevent deep vein thrombosis.

Key words: low molecular weight heparin （LMWH）, spinal fracture, spinal cord injury, deep vein thrombosis (DVT), bleeding