Bone swelling is a condition of inflammation marked by an increase of fluid buildup and pain in and around a bone. There may also be a decreased ability to move the particular body part involved. The protective response of swelling helps guard the injured area from further damage and aids in the healing process.
Since bones are made of a dense, hard material on the exterior, most bone swelling occurs around the bone or in the joint spaces connecting one bone to another. Swelling due to excessive fluid, however, can occur inside the flexible material located in the center of the bone called the bone marrow. Bone marrow edema is an instance where there is an excess of fluid inside the bone itself.
Causes of bone swelling can range from an injury such as a blow to the bone, often referred to as a bone contusion or bruise. A fracture or break of the bone, especially if it is an open fracture where the bone protrudes through the skin, can cause swelling either of the surrounding area or of the bone marrow if bacteria gains entrance through the fracture. Other conditions which may produce this swelling include degenerative diseases such as rheumatoid arthritis; autoimmune diseases such as lupus; and some forms of cancer such as osteosarcoma, cancer of the bone, and chrondrosarcoma, cancer of the cartilage surrounding a bone.
Osteomyelitis or bone infections may also cause bone swelling. A bone infection is commonly bacterial. It invades the bone and can cause damage to the bone's blood supply as well as to the integrity of the bone itself. Bone infections can occur not only from a bone fracture but also from general infection processes such as pneumonia or urinary tract infections, where the bacteria travels through the blood stream and into the bones.
Bone swelling is characterized by puffiness and pain or tenderness over the area. The area may be warm to the touch and mobility of the body part involved may be limited; in severe cases, there may be an inability to move the affected area at all. If swelling is caused by an infection, it may be accompanied by fever, chills, or nausea.
Treatment of bone swelling depends on the cause. When it is due to an injury a period of ice, rest and immobility with the use of a compression bandage may decrease symptoms. If the swelling is due to an infection, proper treatment of the infection with antibiotics can decrease pain. In some instances, excessive fluid buildup requires draining. In extreme cases, surgery may be necessary to remove fluid and damaged bone to avoid further problems.