Septic Arthritis

Septic arthritis is a type of arthritis that happens when an infection causes inflammation inside one of your joints. That’s why it’s also known as infectious arthritis.

The inflammation in your affected joint causes common arthritis symptoms like pain and swelling. Unlike other kinds of arthritis, septic arthritis is curable. Once a healthcare provider treats the infection that’s causing it, the inflammation will get better, and symptoms should go away.

But it’s extremely important to get septic arthritis treated right away. An infection that’s spreading in your body can be dangerous. And if it’s not treated soon enough, the inflammation can permanently damage your joint.

Septic arthritis can affect any joint. It’s most common in big joints like your:

• Hips
• Knees
• Ankles
• Shoulders

It’s also possible to get septic arthritis in an artificial joint. It can be a complication after joint replacement surgery.

What are the symptoms of septic arthritis?

Symptoms of septic arthritis can include:

• Pain and tenderness in your affected joint
• Swelling and a feeling of warmth in your affected joint
• Limited range of motion in your affected joint
• Not wanting to use or move your affected joint
• Fever

Most people only get infectious arthritis in one joint at a time. But it can spread to more than one. This is more common in babies. Babies with infectious arthritis may be fussier and seem more uncomfortable than usual.

Septic arthritis causes

Infections that spread to your joints cause septic arthritis. Any type of infection can cause it, including:

• Bacterial infections
• Fungal infections
• Viral infections

Bacterial infections are by far the most common cause. Bacteria are much more likely than other kinds of infections to spread through your blood and invade your joint’s tissues. Staph infections are the most common infection that leads to septic arthritis.

Risk factors in children

Infectious arthritis is more common in children than in adults. That’s because kids get sick more often. Their immune systems haven’t had time to fully develop yet. Your child may be more likely to develop septic arthritis from an infection if they:

• Are younger than 1
• Have a weakened immune system
• Have hemophilia
• Have HIV/AIDS
• Have cancer or are receiving chemotherapy

Adult risk factors

The same kinds of health conditions that increase children’s risk of septic arthritis apply to adults, too. Other factors that may make you more likely to develop it include:

• Having other types of arthritis
• Getting sick a lot, especially if you have a weakened immune system
• Taking immunosuppressants
• Having a recent surgery or injury that increases your risk of getting a bacterial infection
• Having a joint replacement
• Being over 80
• Using recreational drugs you inject with needles

Complications of septic arthritis

Septic arthritis is usually temporary. But it can cause some serious complications if the infection isn’t treated. Complications can include:

• Permanent joint damage
• Septicemia
• Sepsis
• Bone infections
• Bone tissue death

How doctors diagnose this condition

A healthcare provider will diagnose septic arthritis with a physical exam and some tests. Your provider will discuss your health history. Tell them any symptoms you’ve noticed and when they first started.

Your provider will use a needle to remove a sample of fluid from your joint if they think you might have infectious arthritis. This is called a joint aspiration. They’ll test the sample for infections. Some infections might not show up in your joint fluid. Your provider might use other tests to diagnose the infection and arthritis, including:

• Imaging tests like X-rays, an MRI or an ultrasound
• Blood tests
• Bacterial culture tests

Septic arthritis treatment

Septic arthritis treatments include:

• Medications to treat the infection: Antibiotics are the most common treatment to kill a bacterial infection. You might need antifungals or antivirals, depending on which infection you have.
• Pain relievers: Your healthcare provider will suggest medications to manage symptoms like pain and swelling.
• Joint aspiration: Your provider may remove fluid from your joint. In addition to helping diagnose the infection, removing fluid or pus can relieve swelling inside your joint.
• Surgery: You might need surgery to remove infected or damaged tissue. You may need surgery to repair or replace an artificial joint if you get septic arthritis after a joint replacement.
• Immobilization: You might need to wear a brace or splint to support your joint while it heals. This will take pressure off it and keep it stable.
• Physical therapy: This will help you regain your strength and mobility. You’ll need to strengthen muscles around your affected joint.

When should I see my healthcare provider?

See a healthcare provider as soon as possible if you notice sudden pain, swelling or symptoms in or around a joint. This is especially true if you develop arthritis symptoms suddenly and you know you have an infection.

How serious is septic arthritis?

Septic arthritis is a serious condition. The longer it takes to get treatment, the more likely you are to experience complications. It can also be fatal if it’s not treated. See a healthcare provider right away if you experience symptoms.

Septic arthritis recovery time

Most people recover fully from septic arthritis if it’s treated soon enough. It can take several weeks. Your recovery may be longer if you need surgery. Several factors can affect your recovery time, including:

• The type of infection you have
• How long it lasts
• Your age and overall health

Some types of bacteria are more challenging to treat than others. An infection that lasts longer is more likely to permanently damage your joint. Your healthcare provider will help you understand what to expect.