BACKGROUND:Percutaneous vertebroplasty and kyphoplasty are both effective in the treatment of osteoporotic vertebral compression fractures, but different in the distribution and dispersion of bone cement. ＜br> OBJECTIVE:To analyze the factors affecting the bone cement dispersion within the vertebral body in treatment of osteoporotic vertebral compression fracture with vertebroplasty or kyphoplasty. ＜br> METHODS:A total of 41 patients with osteoporotic vertebral compression fractures were included, and divided into three groups:group A (22 cases receiving high viscosity bone cement vertebroplasty treatment), group B (5 cases receiving high viscosity bone cement kyphoplasty), group C (14 cases receiving low viscosity bone cement vertebroplasty treatment). The groups A and C were divided into subgroups according to bone cement injection volume, time from fracture to operation, preoperative degree of vertebral compression. The distribution and dispersion of bone cement in the vertebra were reconstructed by the CT three-dimensional imaging and volume rendering analysis. ＜br> RESULTS AND CONCLUSION:In the three groups, after operation, relative dispersion area and relative dispersion volume in the vertebrae had no obvious difference, and the bone cement could al diffuse to upper and lower lamina cross the vertebral midline. There was no significant difference in bone cement diffusion coefficient among the three groups. In a certain range, the bone cement injection volume and bone cement dispersion volume was positively correlated. In groups A and C, bone cement diffusion coefficient decreased with the increasing of bone cement injection volume, time from fracture to operation, and the compression degree of the fractured vertebrae, but showed no significant correlation with bone cement viscosity.