Fundamental subchondral bone changes in spontaneous knee osteoarthritis.

Osteoarthritis has an unknown aetiology, and tissue samples from early stage human osteoarthritis tissue cannot be reliably obtained. Therefore understanding the development of OA relies on using animal models: such as the spontaneous changes seen in the Dunkin-Hartley guinea pig strain, which are biochemically, histologically and radiologically similar to human OA. We investigated the role of bone change in early OA development using the non-OA developing Bristol strain-2 as control from 3 to 36 weeks by standard microfocal X-ray imaging and histological techniques.