title: Measurement of human trabecular bone by novel ultrasonic bone densitometry based on fast and slow waves.
abstract: CONCLUSIONS
  Two longitudinal transmitted waves, fast and slow waves, were observed by employing a new quantitative ultrasound (QUS) method. The trabecular bone measurements generated by this method reflect three-dimensional structural information, and the new QUS parameters were able to identify vertebral fractures.
  
  
  BACKGROUND
  The aims were to identify new quantitative ultrasound (QUS) parameters that based on new QUS method reflecting not only bone volume but also the microstructures of trabecular bone ex vivo and to observe how much they predict fracture risk in vivo.
  
  
  METHODS
  Ex vivo measurement: Three human femoral heads were used for the experiment. Attenuation of the slow wave, attenuation of the fast wave, speed of the slow wave, speed of the fast wave (SOFW), bone mass density of trabecular bone, and elastic modulus of the trabecular bone (EMTb) of each specimen were obtained using a new QUS method and compared with three-dimensional structural parameters measured by micro-computed tomography. In vivo measurement: Eighty-nine volunteers were enrolled, and the bone status in the distal radius was measured using a new QUS method. These parameters were compared with data evaluated by peripheral quantitative computed tomography and dual X-ray absorptiometry.
  
  
  RESULTS
  Ex vivo measurement: SOFW and EMTb showed correlations with the parameter of trabecular anisotropy. In vivo measurement: The new QUS parameters were able to identify vertebral fractures.
  
  
  CONCLUSIONS
  The newly developed QUS technique reflects the three-dimensional structure and is a promising method to evaluate fracture risk.
authors.affiliation: Department of Orthopedic Surgery, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: T
authors.initials: T
authors.lastname: Otani
authors.forename: H
authors.initials: H
authors.lastname: Hagino
authors.forename: H
authors.initials: H
authors.lastname: Katagiri
authors.forename: T
authors.initials: T
authors.lastname: Okano
authors.forename: I
authors.initials: I
authors.lastname: Mano
authors.forename: R
authors.initials: R
authors.lastname: Teshima
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D003720:Densitometry / Q000379:methods; D005260:Female; D005270:Femur Head / Q000000981:diagnostic imaging*; D006801:Humans; D021621:Imaging, Three-Dimensional; D007564:Japan; D008297:Male; D008875:Middle Aged; D011884:Radius / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods; D014463:Ultrasonography