Risk factors of developing new symptomatic vertebral compression fractures after percutaneous vertebroplasty in osteoporotic patients

Percutaneous vertebroplasty (PVP) is an efficient procedure to treat pain due to osteoporotic vertebral compression fractures (OVCFs). However, some patient populations experience recurrent vertebral fracture after initial successful procedure. There are a lot of literatures about the effectiveness of this procedure but few concerning the development of recurrent, new compression fracture. This is a retrospective review of all PVPs performed in author's institution from September 1999 to December 2001 to investigate the factors related to the development of new symptomatic OVCFs after PVPs. A retrospective review of 244 cases of PVP for symptomatic OVCFs at 382 levels was performed. Sociodemographic, clinical, radiologic, and procedural data were analyzed and compared between the two patient groups (control group : no further symptomatic OVCFs after the initial PVP, "new symptomatic fracture" group: with newly developed symptomatic OVCF). Statistical analysis was performed between the variables of the two groups. Survival analysis was performed using the Kaplan-Meier method. Over all, 38 among 244 treated patients (15.6%) had experienced newly developed symptomatic OVCF(s) during the follow up period (mean 52.5 months). Old age and the presence of multiple treated vertebrae at the initial PVP were assessed as a strong parameter for predicting new symptomatic OVCF. With increasing preoperative wedging deformity the risk of developing new symptomatic OVCF decreased. The Kaplan-Meier estimate of the 1 year fracture-free rate was 92.2%. The Kaplan-Meier curve showed that 7.8% of the patients would experience new symptomatic OVCF within 1 year after initial PVP. A preoperative only mild wedge deformity of the fractured vertebra(e) could indicate the increased risk of developing new symptomatic OVCF after vertebroplasty.