What Is Enthesitis?

Osteoarthritis and Rheumatoid Arthritis Are Associated with Enthesitis

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If you have seen the words entheses, enthesitis or enthesopathy in your x-ray or medical reports, you may have been unclear about their meaning.

  • What is enthesitis?
  • What are the symptoms?
  • How is enthesitis treated?
  • Is enthesitis more common with certain types of arthritis?

What Is Enthesopathy?

Enthesopathy is a condition that affects the entheses (e.g., inflammation of the entheses). The entheses are sites of tendinous or ligamentous attachment to the bone.

Enthesopathy may be due to an inflammatory condition, such as psoriatic arthritis, or a condition due to injury or overload, such as plantar fasciitis.

Symptoms Associated With Enthesitis

Symptoms include pain and often swelling. In addition to pain and swelling of the heel, other commonly affected areas include the toes and fingers. Toes and fingers can look like a sausage due to swelling at the entheses. With enthesitis, the elbow, pelvis and chest wall may also have pain or swelling. Of note, enthesitis doesn't always result in clinically evident swelling. Instead, sometimes a physician needs to palpate or feel an affected area to elicit the pain of enthesitis.

Conditions Associated With Enthesitis

Conditions associated with enthesitis include:

  • Achilles tendinitis
  • reactive arthritis
  • ankylosing spondylitis
  • rheumatoid arthritis
  • osteoarthritis
  • diffuse idiopathic skeletal hyperostosis (DISH)

Enthesitis and Reactive Arthritis

Reactive arthritis is a form of arthritis that results from infection.

The swelling of reactive arthritis is often triggered by infection in a more remote body part, such as the urinary tract, intestines or genitals.

Typically the joints of the knees, feet and ankles are targets for inflammation secondary to reactive arthritis. More specifically, enthesitis, or inflammation of the tendons and ligaments, in people with reactive arthritis usually occurs in the plantar fascia, pelvic bones or Achilles tendon.

Reactive arthritis is uncommon, and this arthritis usually goes away in most people within a year after it begins.

Enthesitis and Ankylosing Spondylitis

Ankylosing spondylitis is an inflammatory condition that most frequently affects men. The inflammation of ankylosing spondylitis affects the vertebrae and causes them to fuse. The inflammation of ankylosing spondylitis can not only result in enthesitis but also affect the eyes.

Chronic enthesitis of the tendons and ligaments of the vertebrae is an important first step in the eventual fusion of vertebrae, which is a hallmark of ankylosing spondylitis. Furthermore, people with ankylosing spondylitis can also experience enthesitis of the costochondral joints, or joints of the ribs. Moreover, about 10 percent of people with ankylosing spondylitis also experience enthesitis of the Achilles tendon and plantar aponeurosis. By the way, the term plantar aponeurosis refers to the thickened connective tissue that supports the arch of the foot.

Treatment of Enthesitis

Treatment of enthesitis is based on the underlying condition.

For example, if enthesitis is due to an inflammatory condition, such as psoriatic arthritis, treatment may include:

  • nonsteroidal anti-inflammatory drugs (NSAIDs) (e.g. ibuprofen, naproxen)
  • methotrexate
  • TNF blockers (which include Enbrel, Remicade, and Humira)

For plantar fasciitis unrelated to an inflammatory condition, heel inserts and NSAIDs are used.


Answer provided by Scott J. Zashin, M.D., clinical assistant professor at University of Texas Southwestern Medical School, Division of Rheumatology, in Dallas, Texas. Dr. Zashin is also an attending physician at Presbyterian Hospitals of Dallas and Plano. He is a fellow of the American College of Physicians and the American College of Rheumatology and a member of the American Medical Association. Dr. Zashin is author of Arthritis Without Pain - The Miracle of Anti-TNF Blockers and co-author of Natural Arthritis Treatment.

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