Osteoarthritis Along with rheumatoid arthritis - a type of inflammatory arthritis - this is one of the two most common types
of
arthritis What causes it?
One million people in the United Kingdom visit their doctor about
osteoarthritis every year. There is no single cause, but several factors seem to increase the likelihood of getting the disease:
Age - osteoarthritis is uncommon before the age of 40
Sex - osteoarthritis is more common in women
Weight - being overweight increases the risk of osteoarthritis, particularly of the knee
Injury - an injury, operation, earlier disease or repeated strain at a joint may lead to osteoarthritis later in life
What happens?
In osteoarthritis, the smooth cartilage that takes the strain in a normal joint becomes rough, brittle and weak. To compensate, the bone beneath thickens and spreads out, forming knobbly outgrowths (osteophytes). The synovial membrane surrounding the joint thickens and the fluid-filled space within it becomes smaller. There is often inflammation.
As osteoarthritis gets worse, bits of cartilage may break away from the bone, causing the bone ends to rub together and the ligaments to become strained. This causes a lot of pain and changes the shape of the joint.
Osteoarthritis is most common in the hands, knees, hips and feet. Some people also develop it in the back and neck.
What does it feel like?
Osteoarthritis develops differently from person to person. The condition typically causes joints to become stiff and painful to move, but it doesn''t usually cause symptoms outside the area of the joint.
It usually develops slowly and the changes can be so gradual that people hardly notice them. The condition usually settles down after a number of years and, although the joints may have a knobbly appearance, they may become less painful.