Altered bone mineral metabolism in patients with osteoarthritis.

OBJECTIVE

Investigation of the relationship between osteoarthritis (OA) and mineral density, and determination of any alteration in bone mineral, metabolism as assessed by biochemical markers of bone resorption and formation.

METHODS

Forty females and 20 males were included in the study. Spinal OA as well as knee OA were defined from radiographs and graded according to Lane et al.'s and Spector et al.'s scoring systems. Bone mineral density (BMD) of the lumbar spine was measured by osteo CT. Bone turnover rates were estimated by measuring biochemical markers of bone resorption (urinary deoxypyridinoline) and bone formation (bone-specific alkaline phosphatase). Forty females and 20 males of the same age were studied as a control group.

RESULTS

BMD was greater in women with spinal OA as compared to controls (P < 0.05). Also, males with OA had a non-significantly higher BMD than controls. The bone resorption markers were higher than normal values. However, they were lower than the control group. Similarly, the bone formation markers were lower as compared to the control group.

CONCLUSION

Spinal OA is associated with higher BMD. This protective effect of spinal OA against osteoporosis may be mediated through decreased rate of bone turnover.