The most common form of arthritis in the United States is osteoarthritis. Approximately twenty-one million adults suffer from osteoarthritis!
Osteoarthritis starts with the breakdown of cartilage in a joint, causing pain and stiffness over time. Symptoms include steady or intermittent pain in a joint, stiffness after inactivity (like sleeping or sitting), swelling or tenderness in the joint, and a crunching sound or feeling when the joint is used. This last is the rubbing of bone on bone called crepitus.
Experts aren’t sure why osteoarthritis happens. Some believe that the joint damage starts in response to physical stress, like an injury or repetitive motion. The stress can wear away the cartilage that cushions the bones and joints in your body. As the cartilage breaks down, the ends of the bone can thicken and rub together. The joint can lose shape, adding to the pain and swelling experienced by a person with osteoarthritis.
The most commonly affected joints are:
- The fingers. Osteoarthritis in the fingers is often hereditary; the base of the thumb joint is most commonly affected. Fingers may become gnarled and enlarged, and bony knobs may develop on the end and middle joints of the fingers. Women are more susceptible to osteoarthritis in the fingers, especially after menopause.
- The knees. The amount of weight that your knees bear makes them especially susceptible to osteoarthritis. The swelling, stiffness, and pain can make it difficult to climb stairs, get into and out of the bathtub, or even take a simple walk.
- The hips. Osteoarthritis in the hip can cause severe pain and disability. The pain may be felt not only in the joint but in the groin, thighs, and knees.
- The spine. Osteoarthritis in the spine can cause pain and stiffness all up and down the back. You may feel discomfort in the neck, or weakness and numbness in the arms and legs.
Other joints — like the wrists, elbows, shoulders, and ankles — are less frequently affected. There may be a history of stress or injury on a particular joint that leads to osteoarthritis. Repetitive use injuries and/or physical trauma can also contribute to the development of osteoarthritis.