title: Non-invasive biomechanical characterization of intervertebral discs by shear wave ultrasound elastography: a feasibility study.
abstract: OBJECTIVE
  Although magnetic resonance is widely spread to assess qualitatively disc morphology, a simple method to determine reliably intervertebral disc status is still lacking. Shear wave elastography is a novel technique that allows quantitative evaluation of soft-tissues' mechanical properties. The aim of this study was to assess preliminary the feasibility and reliability of mechanical characterization of cervical intervertebral discs by elastography and to provide first reference values for asymptomatic subjects.
  
  
  METHODS
  Elastographic measurements were performed to determine shear wave speed (SWS) in C6-C7 or C7-T1 disc of 47 subjects; repeatability and inter-operator reproducibility were assessed.
  
  
  RESULTS
  Global average shear wave speed (SWS) was 3.0 ± 0.4 m/s; measurement repeatability and inter-user reproducibility were 7 and 10%, respectively. SWS was correlated with both subject's age (p = 1.3 × 10(-5)) and body mass index (p = 0.008).
  
  
  CONCLUSIONS
  Shear wave elastography in intervertebral discs proved reliable and allowed stratification of subjects according to age and BMI. Applications could be relevant, for instance, in early detection of disc degeneration or in follow-up after trauma; these results open the way to larger cohort studies to define the place of this technique in routine intervertebral disc assessment.
  
  
  CONCLUSIONS
  A simple method to obtain objectively intervertebral disc status is still lacking. Shear wave elastography was applied in vivo to assess intervertebral discs. Elastography showed promising results in biomechanical disc evaluation. Elastography could be relevant in clinical routine for intervertebral disc assessment.
authors.affiliation: Arts et Métiers ParisTech, LBM, 151 bd de l'hôpital, 75013, Paris, France, c.vergari@gmail.com.
authors.forename: Claudio
authors.initials: C
authors.lastname: Vergari
authors.forename: Philippe
authors.initials: P
authors.lastname: Rouch
authors.forename: Guillaume
authors.initials: G
authors.lastname: Dubois
authors.forename: Dominique
authors.initials: D
authors.lastname: Bonneau
authors.forename: Jean
authors.initials: J
authors.lastname: Dubousset
authors.forename: Mickael
authors.initials: M
authors.lastname: Tanter
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Gennisson
authors.forename: Wafa
authors.initials: W
authors.lastname: Skalli
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D002358:Cartilage, Articular / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002574:Cervical Vertebrae; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging* / Q000503:physiopathology; D055959:Intervertebral Disc Degeneration / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D055815:Young Adult