Risk factors for newly developed osteoporotic vertebral compression fractures following treatment for osteoporotic vertebral compression fractures.

Background Context: It has been reported that newly developed osteoporotic vertebral compression fractures (OVCFs) occur at a relatively high frequency after treatment. While there are many reports on possible risk factors, these have not yet been clearly established.

Purpose: The purpose of this study was to investigate the risk factors for newly developed OVCFs after treatment by vertebroplasty (VP), kyphoplasty (KP), or conservative treatment.

Study Design/setting: A retrospective comparative study.

Patient Sample: One hundred thirty-two patients who had radiographic follow-up data for one year or longer among 356 patients who were diagnosed with OVCF and underwent VP, KP or conservative treatment between March 2007 and February 2016.

Outcome Measures: All records were examined for age, sex, body mass index (BMI), rheumatoid arthritis and other medical comorbidities, osteoporosis medication, bone mineral density (BMD), history of vertebral and nonvertebral fractures, treatment methods used, level of fractures, and presence of multiple fracture sites.

Methods: Patients were divided into those who manifested new OVCF (Group A) and those who did not (Group B). For the risk factor analysis, student's t-tests and chi-square tests were used in univariate analysis. Multivariate logistic regression analysis was carried out on variables with a p<.1 in the univariate analysis.

Results: Newly developed OVCFs occurred in 46 of the 132 patients (34.8%). Newly developed OVCF increased significantly with factors such as average age (p=.047), low BMD T-score of the lumbar spine (p=.04) and of the femoral neck (p=.046), advanced age (>70 years) (p=.011), treatment by cement augmentation (p=.047) and low compliance with osteoporosis medication (p=.029). In multivariate regression analysis, BMD T-score of the lumbar spine (p=.009) and treatment by cement augmentation (p=.044) showed significant correlations with the occurrence of new OVCFs with a predictability of 71.4%.

Conclusion: Osteoporotic vertebral compression fracture patients with low BMD T-score of the lumbar spine and those who have been treated by cement augmentation have an increased risk of new OVCFs after treatment and, therefore, require especially careful observation and attention.