Joint Inflammation (Inflamed Joints)

What joint inflammation looks and feels like

Every movable joint is lined by a thin membrane, the synovium, which makes lubricating fluid. When the synovium becomes inflamed, it thickens and produces excess fluid. The classic signs are:

• Swelling: the joint looks puffy or feels spongy. Knuckles lose their normal contours.
• Warmth: the joint feels warmer than the same joint on the other side.
• Redness: most obvious in gout and infection.
• Stiffness: especially after rest and first thing in the morning.
• Pain: both at rest and with movement, and limited range of motion.

This is different from joint pain without inflammation, such as the pain of mild osteoarthritis or tendon strain, where the joint looks normal. See joint pain for causes of aching joints in general.

Causes by pattern

One joint, sudden onset (hours to a day)

• Gout: uric acid crystals. Classically the big toe, also ankle, knee or wrist. Extremely painful, often overnight; even a bedsheet hurts. Triggered by alcohol, red meat, seafood, dehydration and diuretics.
• Pseudogout: calcium crystals, usually in the knee or wrist of older adults.
• Septic arthritis: a bacterial infection inside the joint. Usually a single large joint (knee, hip), with fever and inability to bear weight. It is a medical emergency.
• Injury: bleeding into the joint (hemarthrosis) after a ligament tear or fracture causes rapid swelling.

A few joints, often the legs

• Reactive arthritis: 1 to 4 weeks after a gut or genital infection, often knees and ankles, sometimes with red eyes and painful urination.
• Psoriatic arthritis: can cause a whole finger or toe to swell like a sausage (dactylitis), with psoriasis or nail pitting.
• Lyme disease: usually a large swollen knee weeks to months after a tick bite.
• Ankylosing spondylitis: inflamed back and sometimes hips, knees or heels.

Many joints, gradual onset

• Rheumatoid arthritis: both sides of the body, especially small joints of the hands, wrists and feet, with morning stiffness over an hour and fatigue.
• Lupus: joint pain and swelling with rashes, mouth ulcers, hair loss or kidney problems.
• Viral arthritis: after parvovirus, hepatitis B or C, rubella, chikungunya or other viruses. Usually settles within weeks.

Inflammatory vs non-inflammatory joint pain

How doctors assess an inflamed joint

1. History: which joints, how fast it started, morning stiffness, skin rashes, eye problems, recent infections, travel, tick bites, family history and medicines.
2. Examination: count of swollen and tender joints, skin and nail changes.
3. Joint aspiration: removing fluid with a needle is the key test for a single hot joint. Fluid is checked for crystals (gout, pseudogout) and bacteria.
4. Blood tests: inflammation markers (CRP, ESR), uric acid, rheumatoid factor and anti-CCP antibodies, ANA, and infection tests.
5. Imaging: X-rays, ultrasound or MRI to look for fluid, inflamed synovium and erosions.

What to do for inflamed joints

While you are waiting to be seen, and for mild flares:

• Rest the joint, but avoid complete immobility for long periods.
• Cold packs wrapped in a cloth, 15 to 20 minutes several times a day, reduce swelling and warmth.
• Raise a swollen ankle or knee.
• Pain relief: an NSAID such as ibuprofen or naproxen at the label dose reduces inflammation. Avoid NSAIDs if you have kidney disease, stomach ulcers, heart failure or take blood thinners. Acetaminophen (paracetamol) helps pain but not inflammation.

Medical treatment depends on the cause: drainage and intravenous antibiotics for infection, colchicine, NSAIDs or steroids for gout attacks, and disease-modifying medicines such as methotrexate for rheumatoid and psoriatic arthritis. For a full overview of the disease group and long-term treatment, see arthritis.

Frequently asked questions

What causes joint inflammation?

The most common causes are crystal deposits (gout and pseudogout), autoimmune diseases (rheumatoid arthritis, psoriatic arthritis, lupus), infections inside the joint, reactions to infections elsewhere, and injury. The pattern of joints affected and the speed of onset help doctors tell them apart.

How can I tell if my joint is inflamed?

An inflamed joint is usually swollen, warmer than the same joint on the other side, stiff after rest and painful to move. Morning stiffness lasting more than 30 minutes is a strong clue. Compare both sides by touch with the back of your hand.

Is a red, hot, swollen joint an emergency?

It can be. A single red, hot, swollen joint with fever may be septic arthritis, which can destroy cartilage within days. Seek same-day emergency care. Even without fever, a hot swollen joint should be seen urgently, as it is often gout and needs diagnosis.

Does joint inflammation go away on its own?

Sometimes. Viral arthritis, a gout attack and reactive arthritis often settle within days to weeks. Rheumatoid arthritis and psoriatic arthritis usually persist and cause permanent damage without treatment, which is why swelling lasting more than 6 weeks needs a rheumatology assessment.

Should I use heat or ice on an inflamed joint?

Use cold for a hot, swollen, newly inflamed joint, because it reduces swelling and warmth. Heat is better for stiffness and aching once the acute flare has settled, or for osteoarthritis. Never apply either directly to skin for more than 20 minutes.