What causes joint swelling?

After a twist, impact, or overload, the joint lining and nearby tissues can become irritated and fill with fluid. Bursitis is swelling of a small cushioning sac, often near the shoulder, elbow, hip, or knee. Osteoarthritis may cause intermittent swelling with pain and reduced movement. Gout and pseudogout are crystal-triggered attacks that can become suddenly tender and swollen. Psoriatic or rheumatoid arthritis can cause ongoing inflammatory swelling, sometimes in several joints. Septic arthritis is infection within a joint and needs rapid attention.

Rest from the activity that worsens symptoms, elevate an affected limb when practical, and use a wrapped cold pack for short periods after an injury. Keep gentle movement within comfort so the joint does not become more restricted. Note whether swelling is sudden or gradual, which joints are involved, and whether there is fever, rash, or a recent wound. Avoid draining or pressing the swelling yourself.

Seek urgent assessment for a hot or red swollen joint, fever, severe pain, rapidly increasing swelling, or inability to move the joint. Arrange a prompt appointment when swelling lasts, keeps returning, affects several joints, or follows a significant injury. New swelling around an artificial joint also warrants timely medical advice.

Ask whether the swelling is inside the joint or in nearby tissue, whether imaging or fluid testing is needed, and what activity is safe. Ask how to manage flares, which medicines fit your health history, and when persistent swelling should be reassessed.