title: Head-trunk kinematics during high-velocity-low-amplitude manipulation of the cervical spine in asymptomatic subjects: helical axis computation and anatomic motion modeling.
abstract: OBJECTIVE
  This study aimed to analyze the in vivo 3-dimensional kinematics of the head during cervical manipulation including helical axis (HA) computation and anatomic motion representation.
  
  
  METHODS
  Twelve asymptomatic volunteers were included in this study. An osteopathic practitioner performed 1 to 3 manipulations (high-velocity and low-amplitude [HVLA] multiple component technique) of the cervical spine (between C2 and C5) with the patient in the sitting position. During manipulation, head motion was collected using an optoelectronic system and expressed relative to the thorax. Motion data were processed to analyze primary and coupled motions and HA parameters. Anatomic motion representation including HA was obtained.
  
  
  RESULTS
  During manipulation, average maximal range of motion was 39° (SD, 6°), 21° (SD, 7°), and 8° (SD, 5°) for lateral bending (LB), axial rotation (AR), and flexion extension, respectively. For the impulse period, magnitude averaged of 8° (SD, 2°), 5° (SD, 2°), and 3° (SD, 2°), for LB, AR, and flexion extension, respectively. Mean impulse velocity was 139°/s (SD, 39°/s). Concerning AR/LB ratios, an average of 0.6 (SD, 0.3) was observed for global motion, premanipulation positioning, and impulse. Mean HA was mostly located ipsilateral to the impulse side and displayed an oblique orientation.
  
  
  CONCLUSIONS
  This study demonstrated limited range of AR during cervical spine manipulation and provided new perspectives for the development of visualization tools, which might be helpful for practitioners and for the analysis of cervical manipulation using HA computation and anatomic representation of motion.
authors.affiliation: Professor, Department of Osteopathic Sciences, Université Libre de Bruxelles, Bruxelles, Belgium. Electronic address: pdugaill@ulb.ac.be.
authors.forename: Pierre-Michel
authors.initials: PM
authors.lastname: Dugailly
authors.affiliation: Scientific Collaborator, Laboratory of Biomechanics, Anatomy and Organogenesis, Faculty of Medicine, Université Libre de Bruxelles, Bruxelles, Belgium.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Sobczak
authors.affiliation: Scientific Collaborator, Laboratory of Functional Anatomy, Faculty of Motor Sciences, Université Libre de Bruxelles, Bruxelles, Belgium.
authors.forename: Bernard
authors.initials: B
authors.lastname: Van Geyt
authors.affiliation: Assistant Teacher, Laboratory of Biomechanics, Anatomy and Organogenesis, Faculty of Medicine, Université Libre de Bruxelles, Bruxelles, Belgium.
authors.forename: Bruno
authors.initials: B
authors.lastname: Bonnechère
authors.affiliation: Assistant Teacher, Research Unit in Osteopathy, Faculty of Motor Sciences, Université Libre de Bruxelles, Bruxelles, Belgium.
authors.forename: Laura
authors.initials: L
authors.lastname: Maroye
authors.affiliation: Scientific Collaborator, Laboratory of Biomechanics, Anatomy and Organogenesis, Faculty of Medicine, Université Libre de Bruxelles, Bruxelles, Belgium.
authors.forename: Fedor
authors.initials: F
authors.lastname: Moiseev
authors.affiliation: Professor and Head of the Department of Anatomy Laboratory of Biomechanics, Anatomy and Organogenesis, Faculty of Medicine, Université Libre de Bruxelles, Bruxelles, Belgium.
authors.forename: Marcel
authors.initials: M
authors.lastname: Rooze
authors.affiliation: Scientific Collaborator, Laboratory of Biomechanics, Anatomy and Organogenesis, Faculty of Medicine, Université Libre de Bruxelles, Bruxelles, Belgium.
authors.forename: Patrick
authors.initials: P
authors.lastname: Salvia
authors.affiliation: Professor, Laboratory of Functional Anatomy, Faculty of Motor Sciences, Université Libre de Bruxelles, Bruxelles, Belgium.
authors.forename: Véronique
authors.initials: V
authors.lastname: Feipel
mesh_terms: D000293:Adolescent; D000328:Adult; D059925:Anatomic Landmarks; D001696:Biomechanical Phenomena; D002574:Cervical Vertebrae; D015331:Cohort Studies; D005240:Feasibility Studies; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D020393:Manipulation, Spinal / Q000379:methods*; D008875:Middle Aged; D008953:Models, Anatomic; D056888:Patient Positioning; D016059:Range of Motion, Articular / Q000502:physiology*; D055815:Young Adult
keywords: Biomechanics; Cervical Manipulation; Kinematics; Range of Motion