Trabecular bone score (TBS) helps to evaluate the bone quality in the lumbar spine using dual-energy X-ray absorptiometry (DXA) scans. The FREEDOM study by McClung MR et al., showed that Denosumab increased BMD and reduced new vertebral fractures in postmenopausal women with osteoporosis.

TBS, a grey-level texture index determined from lumbar spine DXA scans, correlates with bone microarchitecture and enhances the assessment of vertebral fracture risk independently of BMD. This retrospective analysis assessed the effect of denosumab on TBS and further the association of TBS to BMD.

The study included postmenopausal women with lumbar spine or total hip BMD T-score <-2.5 and -4.0 or higher at both sites were involved. They were provided with placebo or Denosumab 60 mg subcutaneously every 6 months. In the study population of 285 women (128 placebo, 157 Denosumab) who had TBS values at baseline and ≥1 postbaseline visit, TBS indices were determined from DXA scans at baseline and then at 12, 24, and 36 months.

The baseline characteristics were comparable between treatment groups. The mean (SD) lumbar spine BMD T-score was -2.79 (0.64) and mean TBS was 1.200). In placebo group from baseline at each visit, the BMD and TBS increased by ≤0.2%. In the Denosumab group, progressive increases from baseline at 12, 24, and 36 months were 5.7, 7.8, and 9.8% for BMD and 1.4, 1.9, and 2.4% for TBS. Percentage changes in TBS were statistically significant compared with baseline (p<0.001) and placebo (p≤0.014). It was observed that TBS was extensively unrelated to BMD, regardless of treatment, either at baseline or for annual changes from baseline (all r²≤0.06).

Overall, it can be concluded that in postmenopausal women with osteoporosis, Denosumab significantly improved TBS independently of BMD.