Bone density and bone turnover in patients with osteoarthritis and osteoporosis

Objective. Osteoarthritis (OA) and osteoporosis (OP) are reported to be rare in the same patient. We examined bone mass, bone turnover, and radiological presence of OA in a group of patients with OA with previous hip fractures and age matched controls. Methods. Bone mass was assessed by bone mineral density (BMD), using dual energy x-ray absorptiometry (DEXA) of the hip and total body and quantitative ultrasound of the os calcis, measuring broadband ultrasound attenuation and velocity of sound. Bone turnover was assessed by measuring urinary pyridinium crosslinks and serum osteocalcin. Results. There were differences in bone density, the patients with OP having lower bone density, while patients with OA had similar or increased bone density compared to controls. Serum osteocalcin showed no significant differences among the 3 groups of patients. Urinary pyridinium crosslinks excretion was significantly elevated in the OA group but not in the OP group compared with controls. Conclusion. Increased bone turnover was restricted to the OA group.