Discrimination of fractures by low-frequency axial transmission ultrasound in postmenopausal females.
CONCLUSIONS
In this cross-sectional study, 95 postmenopausal women, with and without fracture history, were measured by low-frequency axial transmission ultrasound. The measured ultrasound velocity discriminated the fractured subjects from the nonfractured ones equally or better than peripheral quantitative computed tomography (pQCT) and dual energy x-ray absorptiometry (DXA). These results suggest that low-frequency ultrasound is suitable for bone fragility assessment.


BACKGROUND
Quantitative low-frequency axial transmission ultrasound is a promising modality for assessing mineral density and geometrical properties of long bones such as radius and tibia. The aim of the current study was to evaluate the ability of low-frequency axial transmission ultrasound to discriminate fractures retrospectively in postmenopausal women.


METHODS
A cross-sectional study involved 95 female subjects aged 45-88 years, whose fracture information was gathered retrospectively. The fracture group was defined as subjects with one or more low-/moderate-energy fractures. The radius and tibial shaft were measured with a custom-made ultrasonometer to assess the velocity of the low-frequency first-arriving signal (V (LF)). Site-matched pQCT was used to measure volumetric cortical and subcortical bone mineral density (sBMD), and cortical thickness (CTh). Areal BMD (aBMD) was measured using DXA for the whole body (WB), lumbar spine, and hip.


RESULTS
The majority (19/32; 59 %) of the fractures were in the upper limb. V (LF) in the radius, but not in the tibia, discriminated fractures with an age- and BMI-adjusted odds ratio (OR) of 2.06 (95 % CI 1.21-3.50, p < 0.01). In the radius, CTh and cortical BMD (CBMD) significantly discriminated fractures, as did the total, cortical, and sBMD in the tibia (adjusted OR 1.35-2.15, p < 0.05). Sensitivity and specificity were similar among all the measurements (area under the receiver operating characteristic curve 0.74-0.81, p < 0.001).


CONCLUSIONS
Low-frequency axial transmission ultrasound in the radius was able to discriminate fractured subjects from the nonfractured ones. This suggests that low-frequency axial transmission ultrasound has the potential to assess bone fragility in postmenopausal women.
Department of Physics, University of Jyväskylä, P.O. Box 35, Jyväskylä, FI-40014, Finland. petro.moilanen@jyu.fi
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P
Moilanen
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M
Määttä
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V
Kilappa
L
L
Xu
P H F
PH
Nicholson
M
M
Alén
J
J
Timonen
T
T
Jämsä
S
S
Cheng
D015502:Absorptiometry, Photon / Q000379:methods; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density / Q000502:physiology; D003430:Cross-Sectional Studies; D005260:Female; D006621:Hip Joint / Q000503:physiopathology; D006801:Humans; D008159:Lumbar Vertebrae / Q000503:physiopathology; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000175:diagnosis / Q000000981:diagnostic imaging; D058866:Osteoporotic Fractures / Q000175:diagnosis / Q000000981:diagnostic imaging*; D011884:Radius / Q000000981:diagnostic imaging / Q000503:physiopathology; D011885:Radius Fractures / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000503:physiopathology; D012189:Retrospective Studies; D013977:Tibia / Q000000981:diagnostic imaging / Q000503:physiopathology; D014057:Tomography, X-Ray Computed / Q000379:methods; D014463:Ultrasonography