Arthritis in the knee
There are three different types of arthritis that can occur in your knees. The most common type is osteoarthritis (OA), a progressive condition that slowly wears away joint cartilage. OA is most likely to occur after middle age. Rheumatoid arthritis (RA) is an inflammatory condition that can strike at any age. Post-traumatic arthritis develops following an injury to the knee. It can occur years after a torn meniscus, ligament injury, or knee fracture.
What are the symptoms of knee arthritis?
A knee joint affected by arthritis may be painful and inflamed. Generally, the pain develops gradually over time, although sudden onset is also possible. Other symptoms include:
- The joint may become stiff and swollen, making it difficult to bend and straighten the knee.
- Pain and swelling may be worse in the morning, or after sitting or resting.
- Vigorous activity may cause pain to flare up.
- Loose fragments of cartilage and other tissue can interfere with the smooth motion of joints.
- Pain may cause a feeling of weakness or buckling in the knee.
- Joint pain may increase with rainy weather.
Which factors may increace the risk of knee arthritis?
- Older age. The risk of knee arthritis increases with age.
- Sex. Women are more likely to develop knee arthritis, though it isn’t clear why.
- Obesity. Increased weight puts added stress on weight-bearing joints, such as your hips and knees. In addition, fat tissue produces proteins that may cause harmful inflammation in and around your joints.
- Joint injuries. Injuries, such as those that occur when playing sports or from an accident, may increase the risk of knee arthritis. Even injuries that occurred many years ago and seemingly healed can increase your risk of arthritis.
- Certain occupations. If your job includes tasks that place repetitive stress on a particular joint, that joint may eventually develop arthritis.
- Genetics. Some people inherit a tendency to develop arthritis.
- Bone deformities. Some people are born with malformed joints or defective cartilage, which can increase the risk of arthritis.