title: Measurement of lumbar spine intervertebral motion in the sagittal plane using videofluoroscopy.
abstract: BACKGROUND
  Static radiographic techniques are unable to capture the wealth of kinematic information available from lumbar spine sagittal plane motion.
  
  
  OBJECTIVE
  Demonstration of a viable non-invasive technique for acquiring and quantifying intervertebral motion of the lumbar spine in the sagittal plane.
  
  
  METHODS
  Videofluoroscopic footage of sagittal plane lumbar spine flexion-extension in seven symptomatic volunteers (mean age = 48 yrs) and one asymptomatic volunteer (age = 54 yrs) was recorded. Vertebral bodies were digitised using customised software employing a novel vertebral digitisation scheme that was minimally affected by out-of-plane motion.
  
  
  RESULTS
  Measurement errors in intervertebral rotation (± 1°) and intervertebral displacement (± 0.5 mm) compare favourably with the work of others. Some subjects presenting with an identical condition (disc prolapse) exhibited a similar column vertebral flexion-extension relative to S1 (L3: max. 5.9°, min. 5.6°), while in others (degenerative disc disease) there was paradoxically a significant variation in this measurement (L3: max. 28.1°, min. 0.7°).
  
  
  CONCLUSIONS
  By means of a novel vertebral digitisation scheme and customised digitisation/analysis software, sagittal plane intervertebral motion data of the lumbar spine data has been successfully extracted from videofluoroscopic image sequences. Whilst the intervertebral motion signatures of subjects in this study differed significantly, the available sample size precluded the inference of any clinical trends.
authors.affiliation: School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong, NSW, Australia.
authors.forename: Steven
authors.initials: S
authors.lastname: Harvey
authors.affiliation: School of Mechanical Engineering, University of Birmingham, Birmingham, UK.
authors.forename: David
authors.initials: D
authors.lastname: Hukins
authors.affiliation: Department of Radiology, Woodend Hospital, Aberdeen, UK.
authors.forename: Francis
authors.initials: F
authors.lastname: Smith
authors.affiliation: Department of Orthopaedics, Woodend Hospital, Aberdeen, UK.
authors.forename: Douglas
authors.initials: D
authors.lastname: Wardlaw
authors.affiliation: Orthopaedics and Trauma, Queen Elizabeth Hospital, Gateshead, UK.
authors.forename: Deiary
authors.initials: D
authors.lastname: Kader
mesh_terms: D001696:Biomechanical Phenomena / Q000502:physiology; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging* / Q000502:physiology; D055959:Intervertebral Disc Degeneration / Q000000981:diagnostic imaging / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D012984:Software; D014741:Video Recording
keywords: Videofluoroscopy; intervertebral motion; lumbar spine; spinal instability; spine kinematics