title: Comparison of an inertial sensor system with a stationary force plate for evaluation of horses with bilateral forelimb lameness.
abstract: OBJECTIVE
  To assess the analytic sensitivity of an inertial sensor system for detection of the more severely affected forelimb in horses with bilateral lameness.
  
  
  METHODS
  18 adult horses with forelimb lameness.
  
  
  METHODS
  Horses were fitted with inertial sensors and evaluated for lameness with a stationary force plate as they were trotted in a straight line. Inertial sensor-derived measurements for vertical head movement asymmetry (HMA) and vector sum (VS) of maximum and minimum head height differences between right and left halves of the stride were used to predict differences in mean peak vertical force (PVF) as a percentage of body weight between the right and left forelimbs. Repeatability was compared by calculation of the intraclass correlation coefficient (ICC) for each variable. Correct classification percentages for the lamer forelimb were determined by use of a stationary force plate as the standard.
  
  
  RESULTS
  SEs of the prediction of difference in PVF between the right and left forelimbs from HMA and VS were 6.1% and 5.2%, respectively. Head movement asymmetry (ICC, 0.72) was less repeatable than PVF (ICC, 0.86) and VS (ICC, 0.84). Associations were positive and significant between HMA (R(2) = 0.73) and VS (R(2) = 0.81) and the difference in PVF between the right and left forelimbs. Correct classification percentages for HMA and VS for detecting the lamer forelimb were 83.3% and 77.8%, respectively.
  
  
  CONCLUSIONS
  Results suggested that an inertial sensor system to measure vertical asymmetry (HMA and VS) due to forelimb lameness in horses trotting in a straight line has adequate analytic sensitivity for clinical use. Additional studies are required to assess specificity of the system.
authors.affiliation: Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA. keegank@missouri.edu
authors.forename: Kevin G
authors.initials: KG
authors.lastname: Keegan
authors.forename: Charles G
authors.initials: CG
authors.lastname: MacAllister
authors.forename: David A
authors.initials: DA
authors.lastname: Wilson
authors.forename: Carl A
authors.initials: CA
authors.lastname: Gedon
authors.forename: Joanne
authors.initials: J
authors.lastname: Kramer
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Yonezawa
authors.forename: Hiromitchi
authors.initials: H
authors.lastname: Maki
authors.forename: P Frank
authors.initials: PF
authors.lastname: Pai
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D005552:Forelimb / Q000503:physiopathology*; D005684:Gait; D006734:Horse Diseases / Q000175:diagnosis* / Q000503:physiopathology; D006736:Horses; D007794:Lameness, Animal / Q000175:diagnosis* / Q000503:physiopathology; D018670:Monitoring, Ambulatory / Q000295:instrumentation / Q000379:methods* / Q000662:veterinary; D009043:Motor Activity; D011312:Pressure; D059015:Wireless Technology / Q000295:instrumentation