Natural history of pain in patients with conservatively treated osteoporotic vertebral compression fractures: results from VERTOS II.

BACKGROUND AND PURPOSE We analyzed the natural course of conservatively treated osteoporotic vertebral compression fractures from VERTOS II, a randomized trial of vertebroplasty and conservative therapy in 202 patients with vertebral compression fractures. We assessed the proportion of patients who developed chronic back pain and possible risk factors. MATERIALS AND METHODS In VERTOS II, the VAS score was assessed at regular intervals until 1 year follow-up. We followed 95 conservatively treated patients until sufficient pain relief, defined as a VAS score ≤3. These patients were censured at the involved follow-up interval. In addition, baseline clinical and imaging data, and class of pain medication used in patients with a VAS score ≤3 at any follow-up interval were compared with those in patients with a VAS score >3 at every follow-up by using logistic regression analysis. RESULTS During 1 year of follow-up, 57 of 95 patients (60%) had sufficient pain relief with VAS scores ≤3. Thirty-eight patients (40%) still had pain with VAS-scores ≥4 at the last follow-up interval of 12 months, despite the use of higher class pain medication. Statistical analysis showed no risk factors. CONCLUSIONS In the VERTOS II trial, most conservatively treated patients with acute osteoporotic compression fractures had sufficient pain relief during the first 3 months. However, after 1 year, a substantial proportion of patients still had disabling pain despite higher class pain medication used. There were no predictors for the development of chronic pain. Patients with continuing pain ≥3 months after the fracture may be candidates for vertebroplasty.