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Updated: Aug 14, 2026
10:16
Production and Targeting of Monovalent Quantum Dots
Published on: October 23, 2014
Relationship among MRTA, DXA, and QUS revisited
Gary M Kiebzak1, Catherine G Ambrose
1Center for Orthopaedic Research and Education, St. Luke's Episcopal Hospital, Houston, TX 77030, USA. gkiebzak@sleh.com
Summary
Commercially available ultrasound devices cannot accurately estimate bone strength. Axial transmission quantitative ultrasound (QUS) of the ulna showed a weak correlation with bone stiffness, indicating it is not a reliable surrogate for in vivo bone strength assessment.
Area of Science:
- Biomedical Engineering
- Orthopedics
- Medical Imaging
Background:
- Direct in vivo measurement of bone strength is crucial for assessing fracture risk.
- Currently, inexpensive, commercially available devices for direct in vivo bone strength measurement are lacking.
- Mechanical Response Tissue Analysis (MRTA) is a prototype device measuring transverse bending stiffness (EI) in vivo.
Purpose of the Study:
- To determine if ultrasound speed of sound (SOS) can serve as a surrogate for bone strength.
- To investigate the correlation between ulna cortical bone SOS and EI measured by MRTA.
- To assess if combining SOS with DXA-derived bone mineral density (BMD) improves the estimation of EI.
Main Methods:
- Compared axial transmission quantitative ultrasound (QUS) derived SOS with MRTA-derived EI in 138 female volunteers.
- Utilized dual-energy X-ray absorptiometry (DXA) for ulna size, bone mineral content (BMC), and BMD measurements.
- Statistical analysis to determine correlations between SOS, BMD, and EI.
Main Results:
- A significant but weak correlation was found between ulna SOS and EI (r = +0.218, r² = 4.8%).
- Combining SOS with total ulna BMD to estimate elastic modulus showed a moderate correlation with EI (r = +0.377).
- The combination of SOS and BMD did not significantly improve the estimation of EI compared to SOS alone.
Conclusions:
- Axial transmission QUS is not a strong in vivo surrogate for estimating transverse bending stiffness or whole bone strength.
- Current QUS technology has limitations in predicting bone mechanical properties accurately.
- Further research is needed to develop reliable, non-invasive methods for in vivo bone strength assessment.
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