Effect of kyphoplasty on survival after vertebral compression fractures

Abstract

Background A growing population of patients with osteoporosis and fragility fractures has developed. Fragility fractures, including vertebral compression fractures, have been associated with increased mortality. Early operative interventions for patients sustaining hip fractures have been found to reduce mortality. Purpose To determine if kyphoplasty improves survival after vertebral compression fractures. Study design A retrospective chart review of all kyphoplasty procedures performed by the same orthopedic surgeon between June 2000 and June 2004 and a review of patients receiving nonoperative care consisting of oral analgesia and an orthosis during the same time period were conducted. Patient sample Patients seen by a single surgeon for an osteoporotic vertebral body fracture. Outcome measures The primary outcome measured was patient death within the study time period. Methods Data from both groups were tabulated and analyzed for statistical differences by Student t test and chi-squared analysis. Kaplan-Meier curves comparing age, medical comorbidity, and surgical intervention were constructed. Log-rank test was used to analyze the survival curves. Results Of the 94 patients who elected for kyphoplasty, 38 patients were deceased at the close of the current study which ended in September 2006, whereas 26 of the 90 patients who elected for conservative therapy had died. Student t test revealed a significant age difference between patients treated with kyphoplasty and those who were treated nonoperatively (p=.0002). Chi-squared analysis revealed a significant difference between the two populations with respect to Charlson score (p=.050) but no statistical difference between the two populations with respect to ASA (p=.81) or gender (p=.1207). Kaplan-Meier curves were constructed to independently assess the influence of age, medical comorbidity, and kyphoplasty on survival. A significant relationship was detected by log-rank test for age (p=.0172), ASA (p=.0497), and Charlson score (p=.0015) but not treatment with kyphoplasty (p=.1037). An age-adjusted mortality rate was calculated and was found to be 35.3 per 1,000 patient-years for the conservative treatment population and 40.1 for the surgical population. A multivariate analysis comparing age, comorbidity, and surgical treatment with survival did not detect a statistical relationship. Conclusion Kyphoplasty did not seem to effect the survival of patients with a vertebral compression fracture.