title: The extremes of spinal motion: a kinematic study of a contortionist in an open-configuration magnetic resonance scanner: case report.
abstract: METHODS
  Observational case study on a female contortionist.
  
  
  OBJECTIVE
  To investigate how the human spine of a young athlete aligns during extreme body contortions.
  
  
  BACKGROUND
  To our knowledge, there are no data available in the literature on the spinal kinematics under extreme body contortions.
  
  
  METHODS
  Conventional and kinematic magnetic resonance imaging was used to study a 22-year-old female Chinese contortionist. The images were analyzed with regard to abnormal segmental motion and degenerative alterations.
  
  
  RESULTS
  No abnormal segmental motion was observed. The patient had a normal spine beside a mild anterior displacement of L1 relative to L2, with mild disc degeneration and small anterior spondylosis. In addition, a mild disc degeneration was observed at T4/5. No other abnormal findings were diagnosed.
  
  
  CONCLUSIONS
  The kinematic magnetic resonance investigation of the presented case did not reveal any evidence for abnormal segmental motion or subluxation in extreme body contortions and indicates that this excessive motion results from extreme spinal flexibility.
authors.affiliation: Center for Spinal Surgery, University of Zurich, Balgrist, Zurich, Switzerland.
authors.forename: Frederik
authors.initials: F
authors.lastname: Hahn
authors.forename: Rudolf
authors.initials: R
authors.lastname: Kissling
authors.forename: Dominik
authors.initials: D
authors.lastname: Weishaupt
authors.forename: Norbert
authors.initials: N
authors.lastname: Boos
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology; D007738:Kyphosis / Q000175:diagnosis / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D009043:Motor Activity; D018583:Pliability; D011187:Posture; D013122:Spinal Diseases / Q000175:diagnosis / Q000503:physiopathology; D013128:Spinal Osteophytosis / Q000175:diagnosis / Q000503:physiopathology; D013131:Spine / Q000473:pathology / Q000503:physiopathology*