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Print this page Normal knee, and one with loss of cartilage About Arthritis Degenerative arthritis Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 - Bald femoral head (no remaining articular cartilage) as a result of inflammatory arthritis Figure 6 - Hip replacement Figure 7 - Hip replacement Arthritis is an umbrella term that actually refers to more than 100 medical conditions that affect 70 million adults and nearly 300,000 children in the United States alone. These conditions share one main common trait: They all affect the musculoskeletal system, specifically the joints. Usually arthritis is associated with pain, swelling, and inflammation in and around the joint area, which can challenge the ability to perform daily tasks, such as brushing teeth, cooking or walking. Some forms of arthritis also affect other organs in the body. These are known as systemic forms of arthritis and can cause damage in the heart, lungs and kidneys, as well as other body organs. For the majority of types of arthritis, there is no known cause or cure. Arthritis is a chronic condition, meaning there is no cure. Treatment generally calls for reducing pain, minimizing damage to joints, and maximizing function. Some lifestyle and genetic risk factors have been identified to increase the potential for arthritis. Risk factors include: Obesity Age Injury Gender (women tend to get arthritis more than men) Genetics The two most common forms of arthritis are osteoarthritis (OA) and rheumatoid arthritis (RA). OA, known as the “wear-and-tear” form of arthritis, usually comes on gradually, taking many years to develop, and begins around age 40. It may only affect a few joints in the body and is more likely to affect the weight-bearing joints, such as the hips, knees, and back. OA is mostly treated with activity modification, weight loss (if necessary), and exercises to maintain joint motion and muscle strength. Pain relief medications are also used. These include acetaminophen, topical analgesics, nonsteroidal anti-inflammatory drugs (NSAIDs), injectable steroids, and viscosupplements injected into the joint (only approved for knees). Over the counter medications such as glucosamine or chondroitin sulfate may also be considered. RA, on the other hand, usually begins earlier, most commonly between the ages of 15 and 50. It tends to be more sudden in development and usually affects smaller joints on both sides of the body, such as the fingers, wrists, elbows and shoulders. However, weight-bearing joints may also be affected. Often with RA, you may feel sick and fatigued. People with RA commonly experienced prolonged morning stiffness. RA is generally treated with pain relievers as well as medication for controlling joint damage and inflammation, including NSAIDs, disease-modifying anti-rheumatic drugs (DMARDs), biologic response modifiers, and glucocorticoids. For most forms of arthritis, there are a number of self-management techniques you can employ to help with your pain and mobility, including: Exercise Balancing activity and rest Managing stress and depression Protecting your joints If you experience joint pain and/or stiffness for more than two weeks, you may need to see a doctor. In the case of RA, it may be important to see an arthritis specialist, called a rheumatologist. More Detailed Explanation The term “arthritis” refers to conditions that result in loss of the lining tissue in joints (“articular cartilage”). Arthritis may be either the more common “wear and tear” type, also known as osteoarthritis, degenerative arthritis, or osteoarthrosis, or the inflammatory type, such as rheumatoid arthritis. Articular cartilage covers the surfaces of bones that form joints. This cartilage surface is extremely smooth, allowing the bones to move past each other without friction. Articular cartilage also acts as a cushion or shock absorber during joint motion (figure 1). The interior of the joint is also lined by a thin tissue called synovium. The synovium is responsible for the production of the fluid that typically is found within the joint. This fluid helps to lubricate the joint and provide some additional cushion. Increases in the amount of fluid make the joint look swollen. The cells in cartilage are able to maintain themselves and the material around them. However, unlike most other tissues that have the ability to repair or form scar, cartilage cannot repair damage on its own. This damage may occur due to injury to the cartilage itself, as a result of overuse or specific trauma, or as a result of changes in the synovium, which may erode into the cartilage. Once cartilage is injured, it can produce substances that lead to local irritation and joint pain. Patients with arthritis may also complain of joint swelling and pain with joint motion or activity. In addition, with the loss of the shock absorber between the bones, more force with activity is placed on the bones, resulting in changes in bone such as bone spurs (“osteophytes”), that may be seen on x-rays. Osteoarthritis or degenerative arthritis occurs as a result of direct cartilage damage, either an acute episode or chronic wear and tear. More than 20 million people in the United States have osteoarthritis. Although it can occur in any joint, degenerative arthritis is most commonly seen in the hip, knee, shoulder, and hands. One of the major risk factors for the development of degenerative arthritis is age: at least 80% of people over the age of 65 will have x-rays findings of osteoarthritis, although not all will have symptoms. However, the development of osteoarthritis is distinct from the normal aging process. In osteoarthritis, the material that forms the gel of the articular cartilage changes, resulting in cartilage that is thinner and more at risk of further damage. Eventually, this cartilage may be completely eroded, leading to exposure of the bone underneath it (new figure showing cartilage erosion on patella). Osteoarthritis may occur in younger people, usually those who have sustained an injury to their articular cartilage (secondary osteoarthritis) (figure 2). It may also occur in younger people with injuries to the bone next to the joint, such as a condition called osteonecrosis (or AVN), in which the bone support to the articular cartilage collapses (figure 3). Inflammatory arthritis occurs as a result of changes in the lining synovium, with secondary damage to the cartilage. The exact cause of the inflammatory arthritis is not known. It may be the result of the body’s own inflammatory cells, which normally work to prevent disease by attacking invading cells, erroneously attacking the cells in the synovium. The synovium and some of the abnormal cells and chemicals produced in the joint will then destroy the adjacent cartilage. The cartilage is eventually worn away, leading to the loss of the normal joint cushion (figures 3,4). The most common of these conditions is rheumatoid arthritis, affecting approximately 1% of the United States population. Rheumatoid arthritis is seen more commonly in women, typically between the ages of 40 and 60 years. However, there is a form known as juvenile rheumatoid arthritis that affects younger people. There are other, less common, types of inflammatory arthritis, which are frequently seen in conjunction with other conditions in other parts of the body. Examples of these are gout, arthritis seen in people with psoriasis, ankylosing spondylitis, Reiter’s syndrome, and arthritis seen in people with inflammatory bowel disease. There is no known cure for arthritis. Treatment is aimed at decreasing pain and improving function to keep people active. Weight loss, muscle strengthening, and range of motion exercises will help with some symptoms. Medications are available, such as acetominophen, nonsteroidal anti-inflammatory drugs (NSAID’s), and glucosamine/chondroitin sulfate, which may also help reduce symptoms. None of these have been shown to repair the damaged cartilage. Medications are also available to slow down the immune process, helping slow the progression of inflammatory arthritis. Another option for treatment is joint injection, either steroids to decrease the inflammation or viscosupplements, which are designed to replicate synovial fluid and restore some of the support to the joint. If pain is not controlled with these measures, surgery may be an option. Surgeries available for arthritis include osteotomies and arthroplasties (joint replacement). Osteotomies are intended for younger people in whom arthritis is limited to one region of the joint. Osteotomies entail cutting the bone next to the joint and realigning the joint to take pressure off of the damaged area. For more extensive arthritis, especially those who are older or who have inflammatory arthritis, joint replacement surgery is an option (figures 6,7). For more information, visit the sections to the top left of your screen for more information and resources, including the Links section to access other web sites, such as that of the Arthritis Foundation. The USBJD thanks the following for their contributions to the content of this section: American Association of Hip and Knee Surgeons Arthritis Foundation www.limbcenter.com Orthopaedic Research Society University of Kansas Medical Center