Foot OA occurs in the foot or feet. The foot contains 28 bones and more than 30 joints. These work together with muscles, tendons, and ligaments to give a wide range of motion. Foot OA can occur for many reasons. It can be due to injury or chronic inflammation of the joint, leading to wear and tear of the cartilage covering the joint.

Osteoarthritis is a degenerative joint disease. Cartilage, which serves as a protective cover and cushion for the ends of the bones that form a joint, gradually wears down. This is due to mechanical wear and tear on the joints of the foot. Injury can also cause osteoarthritis to develop even years after the injury has occurred.

Osteoarthritis is known as wear and tear arthritis, which is expected as people age but can also affect younger people. OA causes joint cartilage to wear away, leading to bone-on-bone pain and bone spurs. When OA affects the feet, it commonly affects the metatarsophalangeal joint (MTP)—the joint that connects the big toe to the foot.

In osteoarthritis, the cartilage in the joint gradually wears away. As the cartilage wears away, it becomes frayed and rough, and the protective space between the bones decreases. This can result in bone rubbing on bone, and produce painful osteophytes (bone spurs).

Osteoarthritis causes damage to the cartilage, which results in pain and swelling, and can sometimes mean the bones rub against each other as we move. Osteoarthritis doesn’t just afect the cartilage, but can also cause damage to the bones, ligaments, tendons and lining of afected joints.