Hypovitaminosis D may be a risk factor for recurrent fracture after kyphoplasty


A study published in The Spine Journal has found that patients who incurred a subsequent vertebral fracture after undergoing kyphoplasty were more likely to have lower levels of  25-hydroxyvitamin D (25 (OH)D) than patients who did not incur a subsequent fracture.

Christos Zafeiris, Laboratory for the Research of Musculoskeletal System, Postgraduate Course on Metabolic Bone Disease, Faculty of Medicine, University of Athens, Greece, and co-investigators reported that although a number of variables (eg, gender) have been evaluated for a potential influence in the risk of recurrent fractures after kyphoplasty, “little and insufficient” data has focused on metabolic profile of patients who undergo kypholasty. Thus, Zafeiris et al reported: “The present study was undertaken to evaluate the incidence of recurrent fractures after kyphoplasty and identify any association between these fractures and the metabolic risk factors.”

Nine of 40 women who underwent kyphoplasty for a vertebral compression fracture developed a subsequent vertebral fracture at an adjacent level. There was no statistical difference between the subsequent fracture group and the no fracture group in bone mineral density measurements (at lumbar spine, femoral neck, ward’s triangle, trochanter, and total femur), but the fracture group had significantly lower levels of 25(OH) D than the no fracture group (14.39±7.47 vs. 22.6±5.51, respectively; p=0.001). Zafeiris et al added: “Higher N-terminal cross-linked telopeptide values, with a statistical trend, were observed in the fracture group in relation with the no fracture group (17.11±10.20 vs. 12.90±4.05; p=0.067).”

The difference in the percentage of patients who had cement leakage between the groups was not significant (33% for the fracture group vs. 17% for the no fracture group), but the presence of cement leakage (all cases were asymptomatic and occurred in the intradiscal space) did increase the risk of recurrent fracture. Zafeiris et al reported: “Our findings demonstrate that an increase by one unit [in 25 (OH) D levels] reduces the fracture probability by 26%, whereas the cement leakage as a complication was a significantly predictor of new vertebral body fracture by 7.96 times (95% confidence interval, 0.74–85.80).”

They concluded: “Bone metabolism and 25(OH) D levels seem to play a role in the occurrence of recurrent vertebral compression fractures after kyphoplasty. Further larger studies are required to systematically analyze the influence of bone metabolism on augementation techniques and draw strong conclusions.”