title: Basic three-dimensional kinematics of the vertebral column of horses walking on a treadmill.
abstract: OBJECTIVE
  To determine kinematic movements of the vertebral column of horses during normal locomotion.
  
  
  METHODS
  5 Dutch Warmblood horses without apparent lameness or problems associated with the vertebral column.
  
  
  METHODS
  Kinematics of 8 vertebrae (T6, T10, T13, T17, L1, L3, L5, and S3) and both tuber coxae were determined, using bone-fixated markers. Horses were recorded while walking on a treadmill at a constant speed of 1.6 m/s.
  
  
  RESULTS
  Flexion-extension was characterized by 2 periods of extension and flexion during 1 stride cycle, whereas lateral bending and axial rotation were characterized by 1 peak and 1 trough. The range of motion for flexion-extension was fairly constant for vertebrae caudal to T10 (approximately 7 degrees). For lateral bending, the cranial thoracic vertebrae and segments in the pelvic region had the maximal amount of motion, with values of up to 5.6 degrees. For vertebrae between T17 and L5, the amount of lateral bending decreased to <4 degrees The amount of axial rotation increased gradually from 4 degrees for T6 to 13 degrees for the tuber coxae.
  
  
  CONCLUSIONS
  This direct measurement method provides 3-dimensional kinematic data for flexion-extension, lateral bending, and axial rotation of the thoracolumbar portion of the vertebral column of horses walking on a treadmill. Regional differences were observed in the magnitude and pattern of the rotations. Understanding of the normal kinematics of the vertebral column in healthy horses is a prerequisite for a better understanding of abnormal function.
authors.affiliation: Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Faber
authors.forename: H
authors.initials: H
authors.lastname: Schamhardt
authors.forename: R
authors.initials: R
authors.lastname: van Weeren
authors.forename: C
authors.initials: C
authors.lastname: Johnston
authors.forename: L
authors.initials: L
authors.lastname: Roepstorff
authors.forename: A
authors.initials: A
authors.lastname: Barneveld
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D005080:Exercise Test / Q000662:veterinary; D005260:Female; D006736:Horses / Q000502:physiology*; D008297:Male; D013131:Spine / Q000502:physiology*