Trabecular bone score as good as BMD at predicting osteoporotic fracture
MedWire News: Trabecular bone score (TBS) is a successful predictor for osteoporotic fracture independent of bone mineral density (BMD), shows research published in the Journal of Bone and Mineral Research.
BMD, measured by dual-energy X-ray absorptiometry (DXA), is the standard diagnostic method for osteoporosis prior to fragility fracture. But inaccuracies exist in using BMD to determine fracture risk. For this reason, other indicators of bone strength are being explored, one of which is TBS.
TBS can be determined from DXA images and, unlike BMD, it correlates with 3D bone microarchitecture parameters.
Didier Hans (university of Lausanne, Switzerland) and colleagues investigated the clinical potential of these TBS measurements.
They assessed the health service records of 29,407 women, age 50 years or over, who had undergone BMD measurement of the spine and hip by DXA for occurrence of osteoporotic fracture. Such fractures were identified in 5.7% of the women, and 24.3% met the World Health Organization criteria for osteoporotic spine BMD; the mean lumbar spine T-score was -1.19.
Hans et al were able to determine lumbar spine TBS from each spine DXA image. They found that both TBS and BMD were significantly lower at the lumbar spine in patients with major osteoporotic fractures than in those without.
They also note that spine TBS and BMD methods were almost equally predictive for fracture, and the combination of the two was significantly better than either one of the methods used alone.
"Our results do not support replacing BMD in favor of TBS. Rather, there may be a role for using these two measurements in combination, especially in those [patients] at intermediate risk, such as individuals with BMD values in the osteopenic range," the researchers write.
They suggest that "if the [TBS] information is easily extracted from DXA and is incremental to BMD," then it could help "define the fracture risk profile by taking into account both the density and the microstructure of the bone."
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By Chloe McIvor