Within your joint capsules, the ends of the two bones are covered with a smooth elastic tissue known as articular cartilage. This prevents your bones from rubbing and grinding against each other. Cartilage acts as a shock absorber as well, cushioning the ends of your bones and distributing stress evenly across your bones. As the cartilage deteriorates, the bone is less protected, and the sufferer experiences pain upon weight bearing, walking and standing.

Changes that occur in the cartilage of people with osteoarthritis include an initial increase in the water content of the cartilage and changes in the quality and quantity of collagen bundles. As the condition progresses, the cartilage fibrillates, there is a loss of cartilage substance, osteophyte formation and an increased bone density below the area of cartilage loss.