The Types of Arthritis

Arthritis is a general term that refers to hundreds of different joint diseases. It affects more than 50 million people in the U.S., according to the Arthritis Foundation. While there are ways to manage these diseases, most forms of arthritis have no cure. It is also often very difficult to pinpoint an exact cause. Here’s a look at the different types of arthritis that can manifest.

Osteoarthritis (Degenerative Joint Disease)

Osteoarthritis is the most common type of arthritis.  When someone says they have arthritis, they are usually referring to osteoarthritis. It may also be known as degenerative joint disease because the joints "degenerate" or decline in function. Cartilage and other structures that provide support during movement wear down.

Typical symptoms include stiffness, swelling, and pain. They are particularly apparent upon waking and during physical activity. There is no exact cause of osteoarthritis, although many factors (such as genetics and weight) can influence its appearance. Additionally, there is no outright cure for osteoarthritis. However, some treatments may help to manage symptoms of the disease. These include anti-inflammatory medications, joint replacement surgeries, and healthy lifestyle activities like exercise.

Inflammatory or Autoimmune Arthritis

This category encompasses a range of different types of arthritis. Inflammatory types of arthritis can be identified by the presence of white blood cells in the joint fluid. This may be accompanied by a persistent fever, a general feeling of weakness, and even issues with the organs.

Rheumatoid arthritis is one of the most common types of autoimmune arthritis. It can be a particularly painful and debilitating chronic disease. Other forms of inflammatory arthritis include gout, pseudogout (CPPD), and lupus. Various types of arthritis can also result from a primary condition (such as psoriatic arthritis). Ankylosing spondylitis is another inflammatory type of arthritis that mainly affects the joints of the spine.

Septic or Infectious Arthritis

Infectious arthritis, or septic arthritis, refers to the many types of arthritis that develop as the result of viral and bacterial infections. It is a form of inflammatory arthritis because of how it manifests (as part of the body's immune response). But septic arthritis is further classified as infectious because of the underlying cause. It is important to note that many forms of arthritis can be categorized in more than one way. There is a lot of overlapping.

For example, reactive arthritis is a specific type of infectious arthritis. This type of arthritis occurs when an infection elsewhere in the body leads to inflammation in the joints. According to the Arthritis Foundation, the most common causes of reactive arthritis are infections of the intestines, genitals, or urinary tract. The distinct difference between infectious and reactive arthritis is that when infectious arthritis occurs, the infection is in the joint itself, rather than elsewhere in the body.

The Arthritis Foundation also reports that Lyme disease, infectious hepatitis, fifth disease, mumps, German measles, and rheumatic fever can cause infectious arthritis.

Anatomical Arthritis

In some cases, arthritis does not affect many different joints throughout the body. Instead, it affects a particular joint or set of joints. Bursitis, an inflammation of the bursa that cushions the joints, and tendonitis. Inflammation of the tendons can be considered arthritis. The back and spine often suffer from a variety of different types of arthritis, such as degenerative disc disease. Other commonly affected areas are the knees, hips, wrists, and elbows.

Secondary Arthritis

Some forms of arthritis develop because of a primary condition that is not viral, bacterial, or otherwise infectious. The primary condition responsible for arthritis can have many different causes and accompanying symptoms. Psoriatic arthritis, for example, is a form of inflammatory arthritis that can appear in tandem with psoriasis. In addition to the symptoms caused by psoriasis, you may experience stiffness, pain, and swelling of the joints.

Juvenile Idiopathic Arthritis (JIA)

Juvenile arthritis is a blanket term for types of arthritis that occur in children (under the age of 16). According to the Arthritis Foundation, more than 300,000 children are afflicted with arthritis. Juvenile arthritis tends to be inflammatory forms or autoimmune reactions. The "idiopathic" in the name denotes that there is most often no directly defined cause of the arthritis. Despite their youth, children experience the same variety of symptoms—painful, stiff, or swollen joints, often accompanied by persistent fever. Rashes may also accompany symptoms of juvenile idiopathic arthritis.