ORIGINAL ARTICLE Generation and validation of a normative, age-specific reference curve for lumbar spine trabecular bone score (TBS) in French women R. Dufour & R. Winzenrieth & A. Heraud & D. Hans & N. Mehsen Received: 5 September 2012 / Accepted: 22 March 2013 # International Osteoporosis Foundation and National Osteoporosis Foundation 2013 Abstract Summary Age-related changes in lumbar vertebral microarchitecture are evaluated, as assessed by trabecular bone score (TBS), in a cohort of 5,942 French women. The magnitude of TBS decline between 45 and 85 years of age is piecewise linear in the spine and averaged 14.5 %. TBS decline rate increases after 65 years by 50 %. Introduction This study aimed to evaluate age-related changes in lumbar vertebral microarchitecture, as assessed by TBS, in a cohort of French women aged 45–85 years. Methods An all-comers cohort of French Caucasian women was selected from two clinical centers. Data obtained from these centers were cross-calibrated for TBS and bone min- eral density (BMD). BMD and TBS were evaluated at L1– L4 and for all lumbar vertebrae combined using GE-Lunar Prodigy densitometer images. Weight, height, and body mass index (BMI) also were determined. To validate our all-comers cohort, the BMD normative data of our cohort and French Prodigy data were compared. Results A cohort of 5,942 French women aged 45 to 85 years was created. Dual-energy X-ray absorptiometry normative data obtained for BMD from this cohort were not significantly different from French prodigy normative data (p =0.15). TBS values at L1–L4 were poorly correlated with BMI (r = -0.17) and weight (r = -0.14) and not correlated with height. TBS values obtained for all lumbar vertebra combined (L1, L2, L3, L4) decreased with age. The magnitude of TBS decline at L1– L4 between 45 and 85 years of age was piecewise linear in the spine and averaged 14.5 %, but this rate increased after 65 years by 50 %. Similar results were obtained for other region of interest in the lumbar spine. As opposed to BMD, TBS was not affected by spinal osteoarthrosis. Conclusion The age-specific reference curve for TBS gen- erated here could therefore be used to help clinicians to improve osteoporosis patient management and to monitor microarchitectural changes related to treatment or other diseases in routine clinical practice. Keywords Bone microarchitecture . DXA (dual-energy X-ray absorptiometry) . Normative data curve . TBS (trabecular bone score) Introduction Osteoporosis is a major public health problem worldwide [1]. It is characterized by low bone mass coupled with alterations in bone microarchitecture [2] that increase bone fragility and, thereby, fracture risk. The diagnosis of osteoporosis is based on the measurement of bone mineral density (BMD), as evaluated by dual-energy X-ray absorptiometry (DXA) and compared against reference BMD data. Low BMD has been recognized as a good predictor of osteoporotic fracture risk [3]. Nevertheless, although widely used, a major limitation of BMD measurement is that a substantial degree of BMD overlap exists between subjects with and without subsequent fractures [4, 5]. This suggests that BMD is not the only R. Dufour Rhône-Durance Clinic, Avignon, France R. Winzenrieth (*) Med-Imaps, Pessac, France e-mail: rwinzenrieth@medimaps.fr A. Heraud Robert Boulin Hospital, Libourne, France D. Hans Center of Bone Diseases, Lausanne University Hospital, Lausanne, Switzerland N. Mehsen Rheumatology Department, Bordeaux University Hospital, Bordeaux, France Osteoporos Int DOI 10.1007/s00198-013-2384-8