Three types of arthritis can affect movement of the knee.
Osteoarthritis is the most common type. It causes cartilage in the knee joint to gradually wear away. Cartilage is a tough, elastic tissue that covers the ends of the bones that make up the joint. It absorbs shock and allows the knee to move smoothly. 
Possible causes of osteoarthritis include a deformity in the knee or a knee injury. Being overweight can also lead to wearing down of cartilage. 
It's most common in older people. Some younger people develop osteoarthritis because of a genetic defect or a knee injury. 
Rheumatoid arthritis is a disease most common in middle-aged people, particularly women. It causes inflammation in the knee joint and can destroy cartilage. Experts don't know what causes the disease. It usually affects both knees, says the <a href="[BASEDOMAIN]/healthinfo/bouncelink.aspx?shortcut=ortho" target="_blank">American Academy of Orthopaedic Surgeons</a> (AAOS). 
Post-traumatic arthritis can develop after injury to the knee. It's similar to osteoarthritis and can develop years after the initial injury. 
Signs and symptoms 
Arthritis causes pain, swelling and stiffness in the knee, says the <a href="[BASEDOMAIN]/healthinfo/bouncelink.aspx?shortcut=niams" target="_blank">National Institute of Arthritis and Musculoskeletal and Skin Diseases</a>. 
Sometimes the joint locks or clicks when the knee moves. 
The knee may swell and it may hurt to walk, climb stairs or kneel. 
Swelling, stiffness and pain may be worse in the morning, says the AAOS. 
The knee may lock up or buckle, causing you to lose support when standing or walking. 
A doctor will use an x-ray or MRI (magnetic resonance imaging) to look for signs of arthritis inside the knee joint. 
Treating the pain 
In the early stages, arthritis is usually treated with medications such as aspirin, acetaminophen, ibuprofen or other pain relievers. Heat or ice also may help. 
A doctor also may recommend lifestyle changes, such as: 
<ul>
 <li>Losing weight. </li>
 <li>Switching from running and jumping exercises to swimming or bicycling. </li>
 <li>Doing exercises to increase strength and flexibility in the legs. </li>
 <li>Using a cane or wearing a brace or knee sleeve. </li>
</ul>
Surgical options
If arthritis is severe, surgery can help. According to the AAOS, surgical options include: 
Arthroscopic surgery&mdash;using a tiny fiberoptic tube to look inside the knee joint and repair cartilage. 
Total or partial knee arthroplasty&mdash;replacing damaged cartilage with metal and plastic parts. 
Osteotomy&mdash;cutting the shinbone or thighbone to improve alignment of the knee joint. This helps restore movement and relieve pain in the knee. 
Cartilage grafting&mdash;taking cartilage tissue from elsewhere to fill a hole in the articular cartilage. This procedure is generally for younger people with small areas of damage. 
 
Synovectomy&mdash;removing the joint lining harmed by rheumatoid arthritis to help with pain and swelling. 
Talk to your doctor if you think you have arthritis or a knee injury. 
Reviewed 4/26/2024

Knee pain: Arthritis

Different types of arthritis can make it difficult and painful to move your knees.