Osteoarthritis is a degenerative disease of joints (osteo=bone and arthritis=inflammation of a joint). The surface of the joint becomes damaged and the surrounding bone and capsule becomes thickened. In a normal joint the bone ends are covered in gristle (cartilage) which cushions the joint and spreads load. The cartilage is very smooth and slippery allowing the bone ends to move freely.
When a joint develops osteoarthritis the cartilage becomes thin and the joint space narrows is no longer lubricated and able to move freely. The surrounding bone thickens and new bone spurs can form at the edges of the joint (osteophytes). The surrounding soft tissues can thicken and the muscles that move the joint become weakened and wasted. The hip joint becomes stiff and painful and can give the sensation of ‘bone rubbing on bone’ and you may be aware of the joint ‘giving way’ on occasions.