Related Experiment Video
Updated: May 22, 2026

Cortical Bone Assessment Using Ultrasonic Guided Waves: A Reproducibility Study in a Healthy Population
Published on: January 31, 2025
Dual energy x-ray absorptiometry and quantitative ultrasound are not interchangeable in diagnosing abnormal bones
J E Williams1, C M Wilson, L Biassoni
1Childhood Nutrition Research Centre, UCL Institute of Child Health, University College London, 30 Guilford St., London, UK. jane.williams@ucl.ac.uk
Objective:
To evaluate whether dual energy x-ray absorptiometry (DXA) and quantitative ultrasound (QUS) classify the same children as 'abnormal' (SD (z) score (SDS) ≤-2).
Methods:
Speed of sound (SOS) was measured at the radius and tibia using QUS and lumbar spine bone mineral density (BMD) using DXA in 621 subjects aged 5-20 years; healthy 412, cystic fibrosis 117 and obese 92.
Results:
BMD SDS positively (p<0.001) and tibia SOS SDS negatively correlated with size (p<0.05). Disagreement between DXA and QUS for 'abnormal' scans occurred in 6-31%. Those with abnormal BMD and normal SOS SDS had lower mean BMI SDS than those with normal BMD and abnormal SOS SDS. SOS measurements were unobtainable in some children, especially in the obese group.
Conclusions:
DXA and QUS identify different individuals as 'abnormal'. Agreement between BMD and tibia SOS is lower in obese subjects. Without a gold-standard, it is difficult to determine which technique is more 'correct'.
More Related Videos
Related Concept Videos
Ultrasonography
During an ultrasonography procedure, a handheld device called a...
X-ray Imaging
Imaging Studies II: Ultrasonography
Ultrasound II: Endoscopic Ultrasound and FibroScan
Endoscopic Ultrasound (EUS):
Ultrasound I: Abdominal Ultrasonography
Abdominal ultrasonography, commonly known as abdominal ultrasound, is a vital, non-invasive medical imaging technique widely used in healthcare.
Procedure:
This diagnostic tool allows the clinician to visually inspect internal structures within the abdomen, including vital organs such as the liver, gallbladder, pancreas, kidneys, and spleen.
The abdominal ultrasound process begins with applying a special gel to the patient's skin over the abdomen. This gel enhances the...

