Comparison of Bone Tissue Elements Between Normal and Osteoarthritic Pelvic Bones in Dogs.

Physiochemical analysis of bones affected with osteoarthritis (OA) can be used to better understand the etiology of this disease. We investigated the percentage of chemical elements in canine pelvic bone affected with varying degrees of OA using a handheld X-ray fluorescence (XRF) analyzer that discriminates magnesium (Mg(12)) through bismuth (Bi(83)). A total of 45 pelvic bones, including both ilium and subchondral acetabular bone plates, were categorized as normal (n = 20), mild grade OA (n = 5), moderate grade OA (n = 15), and severe grade OA (n = 5). In normal pelvic, seven elements (P, Ca, Mn, Ag, Cd, Sn, and Sb) differed (p < 0.005) in percentage between ilium and acetabulum. Comparisons among the four OA groups found Mn and Fe to be highest in severe grades (p < 0.05) in both ilium and acetabulum. Three heavy metals (Ag, Sn, and Sb) were detected in high percentages (p < 0.05) in the severe OA group in the acetabulum, but in ilium only Sn was high (p < 0.05) in severe OA. In conclusion, the percentages of several elements differed between pelvic types in dogs, and also with increasing severity of OA. The finding of high Mn and Fe in severe grade OA bone suggests these two elements may be useful in future studies of the etiology and pathophysiology of OA.