Also called “wear and tear” arthritis or degenerative joint disease, osteoarthritis (OA) is the progressive breakdown of the joints’ natural shock absorbers. This can cause discomfort when you use the affected joints — perhaps an ache when you bend at the hips or knees, or sore fingers when you type. Most people over 60 have some degree of OA, but it also affects people in their 20s and 30s.
Osteoarthritis: Where Does It Hurt?
In most cases, osteoarthritis develops in the weight-bearing joints of the knees, hips, or spine. It’s also common in the fingers. Other joints such as the elbow, wrist, and ankle are usually not affected, unless an injury is involved.
Osteoarthritis: What Causes It?
Every joint comes with a natural shock absorber in the form of cartilage. This firm, rubbery material cushions the ends of the bones and reduces friction in healthy joints. In general, as we age our joints become stiffer and cartilage can become more vulnerable to wear and tear. At the same time, repetitive use of the joints over the years irritates the cartilage. If it deteriorates enough, bone rubs against bone, causing pain and reducing range of motion.
Because injured joints are more vulnerable to osteoarthritis, doing anything that damages the joints can raise your risk. This includes sports that have a high rate of injury and jobs that require repetitive motion, such as bending the knees to install flooring. Obesity is another risk factor — it has been linked specifically to osteoarthritis of the hands, knees and hips.