title: In vivo assessment of lumbar vertebral strength in elderly women using computed tomography-based nonlinear finite element model.
abstract: METHODS
  In vivo study of a computed tomography (CT)-based nonlinear finite element model (FEM).
  
  
  OBJECTIVE
  To establish an FEM with the optimum element size to assess the vertebral strength by comparing analyzed data with those obtained from mechanical testing in vitro, and then to assess the second lumbar (L2) vertebral strength in vivo.
  
  
  BACKGROUND
  FEM has been reported to predict vertebral strength in vitro, but has not been used clinically.
  
  
  METHODS
  Comparison among the 3 models with a different element size of 1 mm, 2 mm, and 3 mm was performed to determine which model achieved the most accurate prediction. Vertebral strength was assessed in 78 elderly Japanese women using an FEM with the optimum element size.
  
  
  RESULTS
  The optimum element size was 2 mm. The L2 vertebral strength obtained with the FEM was 2154 +/- 685 N, and the model could detect preexisting vertebral fracture better than measurement of bone mineral density.
  
  
  CONCLUSIONS
  The FEM could assess vertebral strength in vivo.
authors.affiliation: Department of Orthopaedic Surgery, School of Medicine, Tokyo University, Bunkyo-ku, Tokyo, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Imai
authors.forename: Isao
authors.initials: I
authors.lastname: Ohnishi
authors.forename: Seizo
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Kozo
authors.initials: K
authors.lastname: Nakamura
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D002102:Cadaver; D019245:Compressive Strength; D005260:Female; D020342:Finite Element Analysis; D006801:Humans; D066298:In Vitro Techniques; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D017698:Postmenopause; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D016103:Spinal Fractures / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control; D013314:Stress, Mechanical; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000502:physiology*; D014057:Tomography, X-Ray Computed; D016474:Weight-Bearing