Osteomyelitis and swelling

Inflammation increases fluid and blood flow around an infected area. The skin may feel warm, look red, or become tender, and movement can become uncomfortable. Swelling may sit over a limb bone, around a wound, or near a joint. A deeper infection can cause pain without an obvious skin change, while a draining opening may appear when infection reaches the skin.

Swelling alone cannot identify osteomyelitis. Sprains, arthritis, blood clots, and other infections can look similar. A clinician may examine the area, check circulation and nerve function, and use blood tests or imaging. A wound or bone sample may be needed to identify the cause and select treatment.

Arrange medical assessment for new swelling with persistent bone pain, warmth, redness, fever, a wound, or recent surgery. Rest the area as advised and protect any wound with the recommended dressing. Avoid massaging an unexplained swollen area, applying leftover antibiotics, or taking someone else’s medicine. Note when the swelling began and whether it is spreading or changing.

Treatment may include antibiotics, drainage, wound care, and an operation to remove infected tissue. When infection has damaged bone, reconstruction can sometimes involve [Bone Grafting](/treatments/trauma-and-fracture-care/bone-grafting/).

Seek urgent care if swelling expands quickly, pain becomes severe, redness spreads, pus appears, or you develop fever with chills. A swollen limb that becomes pale, blue, cold, numb, or difficult to move needs immediate attention. Swelling with severe back pain, weakness, or bladder changes is also an emergency.

Ask whether the swelling appears to involve bone, joint, or soft tissue; which tests are appropriate; how to protect the area while waiting; and which changes should prompt urgent review.