Overview of Osteoarthritis
Osteoarthritis is a degenerative joint disease, in which the tissues in the joint break down over time. It is the most common type of arthritis and is more common in older people.
People with osteoarthritis usually have joint pain and, after rest or inactivity, stiffness for a short period of time. The most commonly affected joints include the:
- Hands (ends of the fingers and at the base and ends of the thumbs).
- Lower back.
Osteoarthritis affects each person differently. For some people, osteoarthritis is relatively mild and does not affect day-to-day activities. For others, it causes significant pain and disability. Joint damage usually develops gradually over years, although it could worsen quickly in some people.
What happens in osteoarthritis?
Researchers do not know what triggers or starts the breakdown of the tissues in the joint. However, as osteoarthritis begins to develop, it can damage all the areas of the joint, including:
- Cartilage, the tissue that covers the ends where two bones meet to form a joint.
- Tendons and ligaments.
- Synovium, the lining of the joint.
- Meniscus in the knee.
As the damage of soft tissues in the joint progresses, pain, swelling, and loss of joint motion develops. If you have joint pain, you may be less active, and this can lead to muscle weakness, which may cause more stress on the joint. Over time, the joint may lose its normal shape. Also, small bone growths, called osteophytes or bone spurs, may grow on the edges of the joint. The shape of the bone may also change. Bits of bone or cartilage can also break off and float inside the joint space. This causes more damage. Researchers continue to study the cause of pain in people who have osteoarthritis.
Who Gets Osteoarthritis?
Anyone can get osteoarthritis; however, it is more common as people age. Women are more likely than men to have osteoarthritis, especially after age 50. For many women, it develops after menopause.
Younger people can also develop osteoarthritis, usually as the result of:
- Joint injury.
- Abnormal joint structure.
- Genetic defect in joint cartilage.
Symptoms of Osteoarthritis
The symptoms of osteoarthritis often begin slowly and usually begin with one or a few joints. The common symptoms of osteoarthritis include:
- Pain when using the joint, which may improve with rest. For some people, in the later stages of the disease, the pain may be worse at night. Pain can be localized or widespread.
- Joint stiffness, usually lasting less than 30 minutes, in the morning or after resting for a period of time.
- Joint changes that can limit joint movement.
- Swelling in and around the joint, especially after a lot of activity or use of that area.
- Changes in the ability to move the joint.
- Feeling that the joint is loose or unstable.
Osteoarthritis symptoms can affect joints differently. For example:
- Hands. Bony enlargements and shape changes in the finger joints can happen over time.
- Knees. When walking or moving, you may hear a grinding or scaping noise. Over time, muscle and ligament weakness can cause the knee to buckle.
- Hips. You might feel pain and stiffness in the hip joint or in the groin, inner thigh, or buttocks. Sometimes, the pain from arthritis in the hip can radiate (spread) to the knees. Over time, you may not be able to move your hip as far as you did in the past.
- Spine. You may feel stiffness and pain in the neck or lower back. As changes in the spine happen, some people develop spinal stenosis, which can lead to other symptoms.
As your symptoms worsen over time, activities that you could participate in become difficult to do, such as stepping up, getting on or off the toilet or in and out of a chair, gripping a pan, or walking across a parking lot.
Pain and other symptoms of osteoarthritis may lead you to feel tired, have problems sleeping, and feel depressed.
Cause of Osteoarthritis
Osteoarthritis happens when the cartilage and other tissues within the joint break down or have a change in their structure. This does not happen because of simple wear and tear on the joints. Instead, changes in the tissue can trigger the breakdown, which usually happens gradually over time.
Certain factors may make it more likely for you to develop the disease, including:
- Being overweight or obese.
- History of injury or surgery to a joint.
- Overuse from repetitive movements of the joint.
- Joints that do not form correctly.
- Family history of osteoarthritis.