Hypovitaminosis D as a risk factor of subsequent vertebral fractures after kyphoplasty

BACKGROUND CONTEXT: Over the past 20 years, methods of minimally invasive surgery have been developed for the treatment of vertebral compression fractures. Balloon kyphoplasty and vertebroplasty are associated with a recurrent fracture risk in the adjacent levels after the surgical procedure. In certain patient categories with impaired bone metabolism, the risk of subsequent fractures after kyphoplasty is increased. PURPOSE: To determine the incidence of recurrent fractures after kyphoplasty and explore whether the status of bone metabolism and 25-hydroxyvitamin D (25(OH)D) levels affect the occurrence of these fractures. STUDY DESIGN: Prospective longitudinal clinical study. PATIENT SAMPLE: Forty female postmenopausal women with primary osteoporosis and acute symptomatic vertebral compression fractures. OUTCOME MEASURES: Identification of new vertebral fractures and documentation of indicators of bone metabolism. METHODS: A total of ninety-eight kyphoplasties were performed in 40 female patients. Balloon kyphoplasty was performed on all symptomatic acute vertebral compression fractures. Age, body mass index, history of tobacco use, number of initial vertebral fractures, intradiscal cement leakage, history of nonspinal fractures, use of antiosteoporotic medications, bone mineral density, bone turnover markers, and 25(OH)D levels were assessed. All participants were evaluated clinically and/or radiographically. Follow-up period was 18 months. RESULTS: The mean population age was 70.6 years (range, 40-83 years). After initial kyphoplasty procedure, nine patients (11 levels) (22.5% of patients; 11.2% of levels) developed a postkyphoplasty vertebral compression fracture. Cement leakage was identified in seven patients (17.5%). The patients without recurrent fractures after kyphoplasty demonstrated higher levels of 25(OH)D (22.6+/-5.51 vs. 14.39+/- 7.47; p = .001) and lower N-terminal cross-linked telopeptide values (17.11+/-10.20 vs. 12.90+/-4.05; p = .067) compared with the patients with recurrent fractures. CONCLUSIONS: Bone metabolism and 25(OH)D levels seem to play a role in the occurrence of postkyphoplasty recurrent vertebral compression fractures. (C) 2012 Elsevier Inc. All rights reserved.