The colors of the different Bone health categories indicate the risk of fracture^*.

The cells are colored from green to red to reflect the level of major osteoporotic fracture risk resulting from the combination of BMD and TBS values:

The “Low risk” category has been defined as the risk of fracture in the normal population, for patients with a normal BMD T-score at any site (spine or hip) and normal TBS value. The other risk categories (“Medium”, “High” and “Very High”) correspond to higher risks as compared to the “Low risk” category.

For example, in a large prospective cohort^*, the risk of Major Osteoporotic Fracture during follow-up was:

• Minimal in the Low risk category (less than 3% of women had an incident fracture). In the other categories, when compared to the Low risk category, the risk is was
• 1 to 3 times higher in the Medium risk category.
• 3 to 5 times higher in the High risk category.
• 5 to 7 times higher in the Very High risk category.

* Adapted from Hans, D., Goertzen, A.L., Krieg, M.-A., and Leslie, W.D. (2011). Bone microarchitecture assessed by TBS predicts osteoporotic fractures independent of bone density: the Manitoba study. J. Bone Miner. Res. 26, 2762–2769.

The black line highlights the separation between low/medium risk and high/very high risk.

TBS iNsight^® provides as an option the adjustment of the BMD T-score, based on the equation that is available in the scientific literature*). No adjustment is done on Bone Mineral density (g/cm2)

The principle is to express the TBS added value as BMD T-score equivalence in term of fracture risk. Then this value is added to the current BMD T-score.

No indication is provided on how to use this adjusted value versus the regular BMD T-score. The formulas to adjust the BMD T-score are explained in the TBS iNsight – Technical Guide (TM-011-005).

* Leslie, W.D., Shevroja, E., Johansson, H., McCloskey, E.V., Harvey, N.C., Kanis, J.A., and Hans, D. (2018). Risk-equivalent T-score adjustment for using lumbar spine trabecular bone score (TBS): the Manitoba BMD registry. Osteoporos Int 29, 751–758.

The BMD T-score adjustment for TBS has been defined from Caucasian women only. Therefore, the BMD T-score adjusted results should not be used for other ethnicities.

The BMD T-score adjusted for TBS is available for the femoral neck BMD, the Total Hip BMD and the Spine BMD. Therefore, the femur must have been analyzed before TBS iNsight can adjust femoral neck or total hip BMD T-score using the TBS value.

The BMD T-score adjustment for TBS has been defined from datasets with L1-L4. Therefore, the BMD T-score adjusted results will not be calculated for other combinations of vertebrae.

No indication is provided on how to use this adjusted value versus the regular BMD T-score.

However, based on the local guidelines in your country, these new decision tools (based on the FRAX Risk adjusted or the BMD T-score adjusted) may help you estimate the actual risk of fracture of the patient and take the most appropriate decisions regarding therapy.

The BMD T-score adjusted for TBS is not included in guidelines yet. This adjustment is based on the equation that is available in the scientific literature^*.

* Leslie, W.D., Shevroja, E., Johansson, H., McCloskey, E.V., Harvey, N.C., Kanis, J.A., and Hans, D. (2018). Risk-equivalent T-score adjustment for using lumbar spine trabecular bone score (TBS): the Manitoba BMD registry. Osteoporos Int 29, 751–758.

As the usual FRAX and BMD T-score values (non-adjusted by TBS) you can use the 2 tools to make a decision according to local guidelines.

A study* has been published in 2019 showing that the BMD T-score adjusted (on femoral neck)  could be used on the FRAX website.

Nevertheless, we recommend to use the unadjusted BMD T-score to compute the FRAX and then adjust it for TBS since the safety and effectiveness of this approach has been verified in several large international prospective cohorts**.

NB: If you use the BMD T-score adjusted by TBS on FRAX website, do not adjust the obtained value with TBS. If you click on “adjust with TBS” you will adjust the FRAX scores twice.

Today there is no evidences showing that the BMD T-score adjusted by TBS could also be used in some other tools for fracture prediction using the BMD T-score information.

* Leslie, W.D., Shevroja, E., Johansson, H., McCloskey, E.V., Harvey, N.C., Kanis, J.A., and Hans, D. (2018). Risk-equivalent T-score adjustment for using lumbar spine trabecular bone score (TBS): the Manitoba BMD registry. Osteoporos Int 29, 751–758.

** A Meta-Analysis of Trabecular Bone Score in Fracture Risk Prediction and Its Relationship to FRAX. J. Bone Miner. Res. 31, 940–948 (2016).