Alajlouni, D., Bliuc, D., Tran, T., Pocock, N., Nguyen, T., Eisman, J. A., & Center, J. (2018). Nonstandard lumbar region in predicting fracture risk. Journal of Clinical Densitometry, 21 (2), 220-226.
Background: Femoral neck BMD is the most commonly used skeletal site to estimate fracture risk. The role of lumbar spine BMD in fracture risk prediction is less clear due to osteophytes that spuriously increase LS BMD, particularly at lower levels. The aim of this study was to compare fracture predictive ability of upper L1-L2 BMD compared to standard L2-L4 BMD and assess whether the addition of either lumbar spine site could improve fracture prediction over FN BMD.
Methodology: A prospective cohort of 3016 women and men 60+ years from the Dubbo Osteoporosis Epidemiology Study followed for occurrence of minimal trauma fractures from 1989 to 2014. DXA was used to measure bone mineral density at f L1-L2, L2-L4 and FN at baseline. Fracture risks were estimated using Cox proportional hazards models separately for each site. Predictive performances were compared using ROC curve analyses
Results:There were 565 women and 179 men with a minimal trauma fracture during a mean of 11±7 years. L1-L2 BMD T-score was significantly lower than L2-L4 T-score in both genders (p
Conclusion: In an elderly population, L1-L2 is as good as but not better than L2-L4 site in predicting fracture risk. The addition of LS BMD to FN BMD provided a modest additional benefit in overall fracture risk. Further studies in individuals with spinal degenerative disease are needed.
osteoporosis; bone mineral density; fracture; fracture risk prediction; lumbar spine