title: A preliminary study into the correlation of stiffness of the laminar junction of the equine hoof with the length density of its secondary lamellae.
abstract: BACKGROUND
  The relationship between mechanical behaviour and microscopic structure of the laminar junction of equine hooves under testing conditions requires elucidation.
  
  
  OBJECTIVE
  To determine mechanical parameters and 2D length density of profiles of secondary lamellae of the laminar junction in the dermal region and to assess possible correlations.
  
  
  METHODS
  Specimens (25 samples in total) of the laminar junction were taken from front, quarter and heel parts from 3 equine hooves and exposed to a uniaxial tensile test until rupture to obtain Young's moduli of elasticity, ultimate stress and strain. Neighbouring specimens to those used for the biomechanical experiment were processed histologically to assess the length density of laminar junction basement membrane using stereological grids.
  
  
  RESULTS
  The estimated median (interquartile range) length density of the laminar junction basement membrane was 0.024 (0.020-0.027)/µm. Young's modulus of elasticity was 0.15 (0.11-0.35) MPa in the small deformation region, and 7.58 (6.14-8.68) MPa in the linear region was. The ultimate stress was 1.67 (1.41-2.67) MPa, and the ultimate strain was 0.50 (0.38-0.70). The Young's modulus of elasticity in the region of small deformations has a moderate correlation with the length density of the laminar junction basement membrane.
  
  
  CONCLUSIONS
  As with most soft biological tissues, the laminar junction has a nonlinear mechanical behaviour. Within the range of small deformations, which correspond to physiological loading of the laminar junction, a higher length density of the laminar junction basement membrane is correlated with a higher resistance of the laminar junction against high stresses transmitted from the distal phalanx to the hoof wall.
  
  
  CONCLUSIONS
  The condition of the laminar junction apparatus may be easily quantified as the length density of profiles of secondary dermal lamellae. This quantification provides a simple tool that could be used for comparing the proneness of the various parts of the laminar junction to initial stages of laminitis.
authors.affiliation: Department of Mechanics, Faculty of Applied Sciences, University of West Bohemia, Pilsen, Czech Republic. kochovap@ntc.zcu.cz
authors.forename: P
authors.initials: P
authors.lastname: Kochová
authors.forename: K
authors.initials: K
authors.lastname: Witter
authors.forename: R
authors.initials: R
authors.lastname: Cimrman
authors.forename: J
authors.initials: J
authors.lastname: Mezerová
authors.forename: Z
authors.initials: Z
authors.lastname: Tonar
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D006724:Hoof and Claw / Q000033:anatomy & histology* / Q000502:physiology*; D006736:Horses / Q000033:anatomy & histology* / Q000502:physiology*