title: Development and validation of a new technique for assessing lumbar spine motion.
abstract: METHODS
  Dynamic lumbar flexion-extension motions were assessed by an electrogoniometer and a videofluoroscopy unit simultaneously.
  
  
  OBJECTIVE
  To develop and validate a new technique for the assessment of lumbar spine motion.
  
  
  BACKGROUND
  Spine instability, a clinical condition that is common but difficult to diagnose, has been suggested to involve a characteristic change in the relation between vertebrae during motion. Assessment of lumbar instability using functional radiographs is controversial. Information regarding dynamic spine kinematics in vivo is limited.
  
  
  METHODS
  A lumbar spine motion analysis system was developed, and its reliability was assessed. Simultaneous total flexion range of motion and segmental motion of the lumbar spine were assessed in 30 healthy volunteers. Lumbar images were captured in 10 degrees intervals during flexion-extension. Intervertebral flexion-extension of each vertebral level was calculated.
  
  
  RESULTS
  In flexion, the lumbar vertebrae flexed with a descending order from L1 to L5 throughout the motion. Conversely, the concavity of lumbar lordosis increased steadily in extension. No statistically significant difference in the pattern of motion was found between genders.
  
  
  CONCLUSIONS
  The results from this study showed that the newly developed technique is reliable. It may have potential value for evaluating spine instability in clinical practice.
authors.affiliation: Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hunghom, Kowloon, Hong Kong. rsswlee@polyu.edu.hk
authors.forename: Sai-wing
authors.initials: SW
authors.lastname: Lee
authors.forename: Kris W N
authors.initials: KW
authors.lastname: Wong
authors.forename: Man-kwong
authors.initials: MK
authors.lastname: Chan
authors.forename: Hon-ming
authors.initials: HM
authors.lastname: Yeung
authors.forename: Jeffrey L F
authors.initials: JL
authors.lastname: Chiu
authors.forename: John C Y
authors.initials: JC
authors.lastname: Leong
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D002138:Calibration; D019937:Diagnostic Techniques and Procedures / Q000295:instrumentation; D005260:Female; D005471:Fluoroscopy / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008161:Lumbosacral Region; D008297:Male; D009068:Movement / Q000502:physiology; D019047:Phantoms, Imaging; D016059:Range of Motion, Articular / Q000502:physiology*; D015203:Reproducibility of Results; D013131:Spine / Q000000981:diagnostic imaging* / Q000502:physiology*; D014741:Video Recording