Study on the Relationship between Cement Injection Rate and Post Operative Vertebral Fracture in PVP

Abstract：Objective Percutaneous vertebroplasty is the most widely used method for the treatment of osteoporotic vertebral compression fractures(OVCF)by injecting bone cement into the fractured vertebral body.The purpose of our study was to identify the possible factors causing adjacent vertebral fractures after vertebroplasty and the appropriate a-mount of bone cement injection.Methods From September 2012 to March 2016,98 patients with OVCF undergoing vertebroplasty were selected and 75 patients with complete follow-up information were included.22 had adjacent verte-bral fracture(refracture group)during the follow-up period,and 53 patients had no adjacent vertebral fracture(control group).Gender,age,body weight,bone mineral density(BMD)and bone cement injection rate(injection volume of bone cement and bone fracture vertebral volume percentage)of the two groups were compared.The correlation between the above factors and adjacent vertebral fracture was analyzed.Results Both groups of patients got effectively relief of back pain.In fracture group,there were 2 male cases and 20 female cases.The mean age was 75.77 years old.The mean weight was 51.24 kilogram.The mean BMD was -2.78 g/m2.In control group,there were 17 male cases and 36 female cases. The mean age was 73.19 years old.The mean weight was 53.08 kilogram.The mean BMD was -2.62 g/m2.Bone ce-ment injection rate were analyzed by ROC curve.The AUC was 0.846(P<0.001),and the cutoff value was 0.405.It was found that the difference of sex,BMD and bone cement injection rate between the two groups were statistically signifi-cant(P<0.05),while it has no significant differences in the age and weight between two groups(P>0.05).Conclusion The bone cement injection rate,BMD value and gender are statistically significantly related to the occurrence of adja-cent vertebral fractures after vertebroplasty,and the cement injection rate is more than 40.5%,which is easy to cause the adjacent vertebral fracture of the vertebral body.