title: The interrelationship of lameness, saddle slip and back shape in the general sports horse population.
abstract: BACKGROUND
  Saddle slip is usually blamed on saddle fit, crooked riders or horse shape, but may reflect hindlimb lameness. There are no studies of the frequency of occurrence of saddle slip and risk factors within a tested sample population of the general sports horse population.
  
  
  OBJECTIVE
  To quantify the frequency of saddle slip and to describe the association with lameness, thoracolumbar shape/symmetry, crooked riders and ill-fitting saddles.
  
  
  METHODS
  Nonrandom, cross-sectional survey using convenience sampling.
  
  
  METHODS
  Five hundred and six sports horses in normal work were assessed prospectively. Thoracolumbar shape/symmetry were measured at predetermined sites; the presence of lameness (in hand and/or ridden) and saddle slip was recorded. Descriptive statistics, univariable and multiple logistic regression were performed to assess the relationship between horse-saddle-rider factors and saddle slip.
  
  
  RESULTS
  The frequency of lameness, quadrilaterally reduced cranial phase of the stride or stiff, stilted canter was 45.7%, saddle slip 12.3%, left-right thoracolumbar shape asymmetries ≥ coefficient of variance of 8% (1.2 cm) 0.6%; and 103 of 276 riders (37.3%) sat crookedly. The saddle consistently slipped to one side in 24.4% of horses with hindlimb lameness alone, 45.5% of horses with concurrent hindlimb and forelimb lameness, compared with 5.4% with forelimb lameness, 17.4% with stiff, stilted canter, 20% with quadrilaterally reduced cranial phase of stride and 5.5% nonlame horses. Nineteen horses (30.6%) with saddle slip had no detectable hindlimb lameness; however, 14 had a gait abnormality, particularly in canter. Multivariable analysis revealed that saddle slip was significantly associated with hindlimb lameness and gait abnormalities (odds ratio [OR] = 52.62, 95% confidence interval [CI] 17.3-159.7), a saddle fitted with even contact and uniform flocking (OR = 15.49, 95% CI 1.9-125.5), riders sitting crookedly (OR = 6.32, 95% CI 2.9-13.7), a well-balanced saddle (OR = 3.05, 95% 1.4-6.9) and large back shape ratio at T18 (OR = 1.2, 95% 1.1-1.3).
  
  
  CONCLUSIONS
  Many horses with hindlimb and/or forelimb lameness go unrecognised. Saddle slip may be a sign of hindlimb lameness. Education of the equestrian population to identify lameness and saddle slip is required. The Summary is available in Chinese - see Supporting information.
authors.affiliation: Centre for Equine Studies, Animal Health Trust, Kentford, Newmarket, Suffolk, UK.
authors.forename: L
authors.initials: L
authors.lastname: Greve
authors.forename: S J
authors.initials: SJ
authors.lastname: Dyson
mesh_terms: D000818:Animals; D001415:Back / Q000033:anatomy & histology*; D001696:Biomechanical Phenomena; D005260:Female; D006734:Horse Diseases / Q000473:pathology*; D006736:Horses; D007794:Lameness, Animal / Q000473:pathology*; D016015:Logistic Models; D008297:Male; D012307:Risk Factors
keywords: gait abnormality; horse; rider position; saddle fit; thoracolumbar asymmetry