Decreased BMD is strongly correlated with increased risk of vertebral fractures; however, in individuals with T2DM, BMD is on average higher than individuals without T2DM, suggesting that in T2DM, BMD underestimates the risk of fracture [
20,
21•]. Trabecular bone score (TBS), a marker of deteriorated trabecular bone quality in patients with T2DM, has been postulated to be helpful in fracture risk assessment in patients with diabetes mellitus [
23‐
25,
26•]. In our study, we reported that individuals with T2DM had higher BMD at the femoral neck and lumbar spine but lower TBS, compared to individuals without T2DM, independent of age, sex, medication use and BMI [
6••]. Yamamoto et al. reported that prevalent vertebral fractures in individuals with T2DM were associated more strongly with TBS than BMD and suggested that an integrated assessment of bone strength by both BMD and TBS would help diagnose diabetic osteoporosis [
27]. Choi et al. found indirect evidence that TBS and TBS-adjusted FRAX could be supplementary tools to predict osteoporotic fractures in T2DM, in a retrospective cross-sectional study of prevalent vertebral fractures in 169 Korean postmenopausal women [
28]. Prediction studies on incident vertebral fractures are desirable. In the study by Zhukouskaya et al., TBS was found not to differ between individuals with or without T2DM and that a combination of TBS below 1.130 and BMD T-score below − 1.0 identified people with T2DM at high risk of vertebral fractures best [
29]. These results need to be interpreted with caution, not only because the sample size is too small to draw solid conclusions but also because the thresholds used in the study are based on absolute values and will always be specific to the population studied and type of DXA used (as it is the case for TBS in this study) [
29]. Similarly, results from the study by Chen et al. should be interpreted with caution, as they used cut-off values for TBS that are not derived from their study population. They reported that low bone mass and deteriorated TBS were noted in approximately two-thirds of women with T2DM and were also associated with vertebral fractures [
30]. We could not find any published article estimating standardized clinical threshold values for TBS neither in individuals without T2DM nor in individuals with T2DM, and therefore, further research to define these thresholds is needed. BMI is a risk factor for vertebral fractures; however, the relationship is complex, with increased BMI correlated with increased bone mass but decreased bone quality [
31]. Furthermore, studies estimating the association between BMI and vertebral fractures in individuals with T2DM are lacking. A study by Kanazawa et al. found that individuals with T2DM falling in the lowest and highest quartiles of BMI had increased risk of vertebral fractures compared to individuals in the middle quartile [
32]. In our recent study, we found that T2DM was associated with increased vertebral fracture risk, only in the underweight category (BMI < 18.5 kg/m
2) and with decreased risk of vertebral fractures in the obese category (BMI > 30 kg/m
2) [
6••]. Decreased muscle mass and mobility as well as increased frailty have been reported in individuals with T2DM compared to controls [
33,
34]. Results from the CaMos cohort suggest that the increased frailty in individuals with T2DM could increase the risk of fragility fractures [
34]. In the STRAMBO study, Schulz et al. found that in older men, moderate and severe vertebral fractures as well as T2DM were independently associated prospectively with lower grip strength, poor physical function, and higher risk of multiple falls [
35]. In a small cross-sectional study among Japanese patients with T2DM, falling was correlated with vertebral fractures [
36]. Vertebral fractures, even though they are often asymptomatic and go undetected, are strongly associated with increased incidence of any type of fracture [
37]. In our recent study, we also examined whether the presence of vertebral fractures in individuals with T2DM predicts future non-vertebral fractures and whether the association differs by BMD levels [
6••]. We found that compared to people without T2DM or vertebral fractures, those who had both T2DM and vertebral fractures had 2.5 times increased hazard ratio to acquire a non-vertebral fracture and a twofold increased hazard when compared to individuals with T2DM alone; the estimated increased risk did not vary when the analysis was stratified by clinical categories of BMD (i.e., normal, osteopenia and osteoporosis), suggesting that presence of vertebral fractures in individuals with T2DM captures an aspect of bone fragility different from that of BMD.