Differences in zinc status, bone turnover and femoral head bone density and biomechanical properties between patients with osteoarthritis and osteoporosis.

and maximum stress, Young’s modulus, energy absorption, and strain were determined. The bone density of the biopsies was determined by ashing. The strength, stiffness, energy absorption, and density of femoral head subchondral trabecular bone were significantly higher in OA patients than in OP patients. The quality of the subchondral trabecular bone was similar for OA and OP patients. The OP patients exhibited significantly higher bone resorption than OA patients, whereas the bone formation marker was similar in the two patient groups. OA patients had significantly higher serum zinc concentrations and significantly lower urine zinc concentrations than OP patients, whereas the bone zinc content did not differ. In conclusion, OA femoral head trabecular bone is stronger, stiffer, and denser than OP bone, whereas the bone quality does not differ. The study confirms the present view that OP and OA are inversely related. In particular, the finding that the zinc status of OP patients is significantly different from that of OA patients is new and adds further support to the view that osteoporosis and osteoarthritis rarely occur in the same individual. J Musculoskelet Neuronal Interact 2008; 8(1):22