title: A horse's locomotor signature: COP path determined by the individual limb.
abstract: BACKGROUND
  Ground reaction forces in sound horses with asymmetric hooves show systematic differences in the horizontal braking force and relative timing of break-over. The Center Of Pressure (COP) path quantifies the dynamic load distribution under the hoof in a moving horse. The objective was to test whether anatomical asymmetry, quantified by the difference in dorsal wall angle between the left and right forelimbs, correlates with asymmetry in the COP path between these limbs. In addition, repeatability of the COP path was investigated.
  
  
  METHODS
  A larger group (n = 31) visually sound horses with various degree of dorsal hoof wall asymmetry trotted three times over a pressure mat. COP path was determined in a hoof-bound coordinate system. A relationship between correlations between left and right COP paths and degree of asymmetry was investigated.
  
  
  RESULTS
  Using a hoof-bound coordinate system made the COP path highly repeatable and unique for each limb. The craniocaudal patterns are usually highly correlated between left and right, but the mediolateral patterns are not. Some patterns were found between COP path and dorsal wall angle but asymmetry in dorsal wall angle did not necessarily result in asymmetry in COP path and the same could be stated for symmetry.
  
  
  CONCLUSIONS
  This method is a highly sensitive method to quantify the net result of the interaction between all of the forces and torques that occur in the limb and its inertial properties. We argue that changes in motor control, muscle force, inertial properties, kinematics and kinetics can potentially be picked up at an early stage using this method and could therefore be used as an early detection method for changes in the musculoskeletal apparatus.
authors.affiliation: Department of Biology, University of Antwerp, Antwerp, Belgium.|Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium.
authors.forename: Sandra
authors.identifier: http://orcid.org/0000-0002-2289-4477
authors.initials: S
authors.lastname: Nauwelaerts
authors.affiliation: Centre for Applied Sport and Exercise Sciences, University of Central Lancashire, Preston, United Kingdom.
authors.forename: Sarah Jane
authors.initials: SJ
authors.lastname: Hobbs
authors.affiliation: Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.|Department of Surgery and Anaesthesiology of Domestic Animals, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Willem
authors.initials: W
authors.lastname: Back
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D006614:Hindlimb / Q000502:physiology*; D006724:Hoof and Claw; D006736:Horses / Q000502:physiology*; D008124:Locomotion / Q000502:physiology*; D008954:Models, Biological