VARIATIONS IN THE BIOMECHANICAL PROPERTIES OF ARTICULAR-CARTILAGE OF THE MIDCARPAL JOINT OF NORMAL HORSES

Carpi from six clinically normal adult horses were used to determine b iomechanical properties of equine midcarpal articular cartilage, and c ompare sites of high and low incidence of osteochondral injury. Test s ites were central and dorsal C-3, both facets, central and dorsal dist al C-R and C-I, central C-4 and C-U. An automated indentation apparatu s was used to obtain creep behaviour, aggregate modulus (H-A), Poisson 's ratio (v(s)), permeability (k), and cartilage thickness (h) at each site. Results were analyzed using ANOVA and multiple comparisons of m eans (p < 0.05). Results revealed significant variations in HA and h b etween test sites, and in HA between dorsal and central sites (p = 0.0 001). Right cartilage overall was stiffer (p = 0.0006), less permeable (p = 0.0001), and more compressible (p = 0.0001) than left. Topograph ical variations in biomechanical properties existed, with significant differences between sites of high and low incidence of lesions, and be tween right and left sides.