title: Reproducibility of kinematic motion coupling parameters during manual upper cervical axial rotation mobilization: a 3-dimensional in vitro study of the atlanto-axial joint.
abstract: BACKGROUND
  The reproducibility of the 3-dimensional (3D) kinematic aspects of motion coupling patterns of segmental manual mobilizing techniques is not yet known. This study analyzes the segmental 3D aspects of manual mobilization of the atlanto-axial joint in vitro.
  
  
  METHODS
  Twenty fresh human cervical specimens were studied in a test-retest situation with two examiners. The specimens were manually mobilized using three different techniques: a regional mobilization technique, a segmental mobilization technique on the atlas with manual fixation of the axis and a segmental mobilization applying a locking technique. Segmental kinematics were registered with a Zebris CMS20 ultrasound-based tracking system. The 3D aspects of motion coupling between main axial rotation and coupled lateral bending were analyzed by six parameters: the range of motion the three motion components, the cross-correlation, the ratio and the shift.
  
  
  RESULTS
  The results indicate stronger intra- than inter-examiner reproducibility. The range of motion of the axial rotation component shows a substantial level of intra- and inter-examiner reproducibility (ICC's 0.67-0.76). The parameters describing the coupling patterns show only moderate to substantial intra-examiner reproducibility for the more experienced of the two examiners (ICC's 0.55-0.68). All other correlations were not significant and no differences could be observed between regional versus segmental techniques.
  
  
  CONCLUSIONS
  Reproducibility of segmental 3D-aspects of manual mobilization of the atlanto-axial joint in an in vitro situation can differ between examiners. The results of the present study may indicate a possible tendency to higher reproducibility if mobilizations are performed by an examiner with high expertise and experience in applying the specific techniques. Continued investigation including more examiners with different levels of experience and different techniques is necessary to confirm these observations.
authors.affiliation: Vrije Universiteit Brussel, Faculty of Physical Education and Physiotherapy, Department of Experimental Anatomy, Laarbeeklaan 103, B1090 Brussels, Belgium. ecattrys@vub.ac.be
authors.forename: E
authors.initials: E
authors.lastname: Cattrysse
authors.forename: S
authors.initials: S
authors.lastname: Provyn
authors.forename: P
authors.initials: P
authors.lastname: Kool
authors.forename: O
authors.initials: O
authors.lastname: Gagey
authors.forename: J P
authors.initials: JP
authors.lastname: Clarys
authors.forename: P
authors.initials: P
authors.lastname: Van Roy
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001268:Atlanto-Axial Joint / Q000000981:diagnostic imaging / Q000502:physiology*; D001696:Biomechanical Phenomena; D002574:Cervical Vertebrae; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D066298:In Vitro Techniques; D008297:Male; D020393:Manipulation, Spinal / Q000379:methods; D008875:Middle Aged; D015588:Observer Variation; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D014463:Ultrasonography