Arthritis - Osteoarthritis, Rheumatoid Arthritis and Gout

Overview

By Tina Shahian, PhD

Arthritis is defined as inflammation of the joints, and is characterized by pain and stiffness around one or more joints. The term arthritis may also be used broadly to describe a number of diseases associated with the breakdown of tissues surrounding the joints, as well as other connective tissues. Severe arthritis can impair limb function; cause deformity of the joints; and, in some cases, affect other organs in the body.

In the United States, the most common types of arthritis are osteoarthritis, rheumatoid arthritis and gout. Some in the medical community include fibromyalgia as a major form of arthritis, while others consider it a separate condition, primarily because one of its characteristics is an absence of joint inflammation or damage.

Depending on the form, arthritis may be caused by aging, autoimmune disorder, infection or other underlying conditions. The main goal of arthritis treatment is to minimize pain and improve physical function. Roughly 50 million Americans report being diagnosed with arthritis, with a higher prevalence in women (24.3%) than in men (18.3%).

Causes and Risk Factors

The cause of arthritis for the types common in the United States are summarized below:

  • Osteoarthritis is associated with normal aging of the joints and affects the joints as well and surrounding tissues (ligaments, cartilage, bone, and lining). The molecular mechanisms responsible for tissue breakdown in osteoarthritis are not fully understood.
  • Rheumatoid arthritis is an autoimmune disorder wherein the body attacks and destroys the lining of the joints (synovial membrane), causing inflammation. Other surrounding tissues including the cartilage and bone can also erode over time.
  • Gout is a metabolic disorder that affects uric acid homeostasis, leading to uric acid crystal buildup in tissues. Deposits in joints and related tissue can lead to the inflammation and pain of arthritis.
  • Fibromyalgia is a condition that causes widespread musculoskeletal pain and other symptoms such as fatigue and sleep disturbance. The mechanism of disease onset is not known.

knee joint cross section showing bones, ligaments and cartilage

Risk factors for developing arthritis are as follows:

  • Family history. Individuals with a family history of arthritis are at a greater risk of inheriting the genetic and environmental factors that lead to disease susceptibility.
  • Obesity. Overweight individuals are at a greater risk of developing osteoarthritis of the knee.
  • Joint injury. Previous joint injury increases the chance of acute arthritis in the affected joint.
  • Age and gender. The risk of some types of arthritis increases with age. Rheumatoid arthritis is more prevalent in women, while gout is more prevalent in men.
  • Infection. Some microbes can target the joints and eventually cause arthritis.

 

Symptoms and Diagnosis

The most common symptoms of arthritis are pain and swelling around the affected joint(s). Arthritis symptoms include:

  • Pain and swelling
  • Stiffness and difficulty moving
  • Redness and/or warmth
  • Limited range of motion.

The first step in diagnosing arthritis is a physical exam to check for swelling, redness, and warmth at the joints. Laboratory tests and visualization methods further help diagnose the disease and assess the extent of tissue damage, respectively.

  • Laboratory tests. Blood, urine, and joint fluid tests help identify infection, elevated uric acid levels, and other potential causes of arthritis.
  • Imaging. A variety of imaging techniques including X-ray, computerized tomography (CT), magnetic resonance imaging (MRI), and ultrasound use radiation, radio waves, or sound waves to produce a detailed image of the joints and surrounding tissues.
  • Arthroscopy. This technique allows visualization of one specific joint by inserting an arthroscope, which is a thin, flexible tube with a camera. The arthroscope is inserted through a small incision at the joint.

Treatment

Arthritis is not a curable disease, the only exception being infectious arthritis, which can be fully treated with antimicrobials and sometimes surgery to remove infected tissue. In most cases, medication and surgical procedures are used to treat the symptoms of arthritis and improve quality of life.

  • Medication. A variety of medications are prescribed to treat the symptoms of arthritis. Analgesics like acetaminophen are a class of drugs used to treat pain, while nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen treat both pain and inflammation. Disease-modifying antirheumatic drugs (DMARDs) and biologic response modifiers are two classes of drugs often used in conjunction to treat rheumatoid arthritis; they act by slowing or blocking the body’s immune system. Corticosteroid drugs like cortisone are used to reduce inflammation and inhibit the body’s immune system.
  • Surgery. Surgical procedures used for improving the physical function of affected joints include joint replacement at the knee and hips, and joint fusion of small joints, such as those of the hands.
  • Physical therapy. Exercises aim to increase range of motion and condition the muscles that support the joints. This treatment approach can help minimize the painful symptoms of arthritis.
  • Home remedies. Staying active with non-weight-bearing exercises (e.g. swimming) and maintaining a healthy weight help improve range of motion and mobility in arthritis patients. Topical hot/cold pads or creams with capsaicin that create a hot sensation on the skin can help minimize pain.

Prevention

Maintaining a healthy weight and avoiding activities that can injure the joints help prevent the onset of arthritis. Early diagnosis and treatment of arthritis symptoms in at-risk individuals help prevent severe damage to joints and surrounding tissues.

Sources

  • “Arthritis”. Medline Plus. NIH. May 2014. Retrieved Jun 2, 2014. http://www.nlm.nih.gov/medlineplus/arthritis.html.
  • "Arthritis". Mayo Clinic. Mayo Foundation for Medical Education and Research. Jan 2013. Retrieved Jun 2, 2014. http://www.mayoclinic.org/diseases-conditions/arthritis/basics/definition/con-20034095.
  • “Arthritis” Centers for Disease Control and Prevention (CDC). CDC. Aug 2011. Retrieved Jun 2, 2014. http://www.cdc.gov/arthritis/basics/types.htm.
  • “What Are Arthritis and Rheumatic Diseases?” National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). NIH. Jul 2009. Retrieved Jun 2, 2014. http://www.niams.nih.gov/Health_Info/Arthritis/arthritis_rheumatic_ff.asp#a.