Monoarthritis, also called monoarticular arthritis, refers to joint inflammation that affects one joint. Monoarthritis is not a type of arthritis itself, but rather a descriptor of the arthritis. Arthritis that affects more than one joint is called polyarticular.

Often, monoarthritis can appear suddenly and cause joint discomfort that ranges from moderate to severe. The condition has several potential underlying causes, including infection, gout, and certain autoimmune diseases.

Read on to learn more about monoarthritis.

Monoarthritis can be a symptom of an underlying infection or other medical condition. Because there are multiple causes, diagnosis can be challenging to doctors, as they seek to rule things out.

Some of the most common causes of monoarthritis are listed.


Conditions that cause crystal deposits to build up in the body are the most common culprits behind monoarthritis. This usually means gout and pseudogout.

uric acid crystals build up in your body and form a deposit at a joint. Your body makes uric acid when it breaks down. These are substances found in alcoholic beverages, red meat, and drinks sweetened with fructose.

A gout flare can last days to weeks, and often begins in the big toe or a lower limb. It can cause intense pain and noticeable swelling.


Infections are a common cause of monoarthritis.

This can be the case in septic (or infectious) arthritis, which occurs due to an underlying infection, typically in the knees or hips. In addition to pain and joint swelling, septic arthritis is often accompanied by typical signs of infection, including fever, chills, and fatigue.

Gonococcal arthritis (arthritis due to a gonorrhea infection) is the most common cause of monoarthritis in young, sexually active people.

If you have had a joint replacement, infection of the areas around the replacement can also potentially cause monoarthritis. Contact your surgeon right away if you’ve had a joint replacement and are experiencing troubling pain or signs of infection. You may need treatment with antibiotics.

Other causes

There are other medical conditions that can cause monoarthritis. These include:

Monoarthritis can occur in 5 to 20 percent of patients whom a doctor will later diagnose with rheumatoid arthritis.

The above conditions can affect more than one joint. It is possible for monoarthritis to progress to inflammation in other joints over time.

Monoarthritis tends to cause acute pain. This means the pain seems to come on suddenly, usually within hours to days.

Some monoarthritis symptoms may include:

  • It usually gets worse with movement.
  • swelling
  • The joint is warm.
  • weakness

A broader range of symptoms depends upon the underlying cause. For example, if RA is causing your monoarthritis, you’ll usually experience joint stiffness in the morning that improves in an hour or less.

Joint stiffness may not be caused by gout in the morning. Infections that cause monoarthritis may have a number of symptoms.

It is important that you consult a medical professional if you have any underlying causes for monoarthritis. If prompt treatment is not given, a case of monoarthritis can get worse.

When evaluating your monoarthritis, your doctor may ask a few questions.

  • When did the pain start?
  • How would you describe the feeling of a joint?
  • Have you had trauma in the past?
  • Do you have any chronic conditions?
  • What are your medications?

Your doctor will perform a physical examination of the joint. They will move the joint around slowly. If you have an infectious disease or have a serious case of arthritis, you may not be able to move the joint.

It is not okay for exams to cause you excessive pain. It is important to communicate with your doctor how you are feeling.

Sometimes, your doctor can be able to identify a cause based on your symptoms and medical history, which is especially true with gout.

Other times a healthcare professional may order additional exams or tests. This may include taking a sample of synovial fluid and sending you to get blood testing or imaging, like an X-ray or MRI.

Treatments depend on the underlying cause. Sometimes monoarthritis can be an emergency. If there is an acute infection or if there is a suspected case of septic arthritis.

Sometimes your healthcare professional will treat you with conservative measures.

If you’re diagnosed with gout, your doctor may prescribe medications like colchicine to reduce excess uric acid buildup. They may also recommend a diet that’s low in purines, the substances that can cause crystal deposits that lead to gout.

If you have an active infection, your doctor may prescribe intravenous or oral antibiotics. It’s important to start antibiotics right away and take them exactly as directed. Conditions like septic arthritis can have serious effects if untreated, including coma and death.

If there are symptoms other than joint pain, there is a medical emergency. If you need immediate medical attention for monoarthritis, you should seek it.

  • You have recently had surgery and experience sudden pain, swelling, warmth, or redness to your joint, which can be a sign of an infection.
  • You have a high temperature and may have an infectious disease.
  • you have joint pain and swellingafter an injury — you may have a fracture or sprain that requires attending

Even if you don’t think your pain is an emergency, consider making an appointment with your doctor if your symptoms interfere with your quality of life. Pain, swellingor redness in a joint should always be evaluated by a professional.

gout or infections can be signs of monoarthritis, which causes pain in one joint. conservative methods like rest and pain medication can be used.

Your doctor will collect a symptom history, conduct a physical exam, and order further tests if he or she finds you to be suffering from monoarthritis.

If your joint pain suddenly becomes more frequent, more severe, or affects your ability to function in daily life, you should seek care.