When leg pain signals an emergency
Most leg pain results from gradual wear and tear or minor issues that will resolve in time or with conservative treatment. Yet, a few symptoms signal a much more serious problem that requires immediate attention. Call a doctor or 911 or go to an emergency room if you think you might have one of these conditions.
Avascular necrosis. Certain diseases, such as sickle cell anemia, or an injury such as a fracture or dislocation can damage the vessels that supply blood to bones in the leg. Also called osteonecrosis, avascular necrosis occurs when a disruption in the blood supply causes the bone to die. Eventually, the bone can break apart and collapse. Symptoms: Bone pain, which may begin suddenly and increases over time.
Bone cancer. Bone cancer is rare, accounting for less than 1% of all cancers. Most cancer in the bones has traveled there from other organs, such as from the breast or prostate gland. Cancer can damage and weaken bone to the point where it fractures. Symptoms: Bone pain, fatigue, unintended weight loss, swelling in the area, fractures, especially in someone with a prior diagnosis of cancer.
Compartment syndrome. In this serious condition, pressure within the muscles and other tissues in the legs builds to the point where it prevents oxygen-rich blood from reaching nerves and muscles. Without treatment, it can lead to permanent muscle and nerve damage. Symptoms: Intense pain, a feeling of tightness or fullness in the affected muscle, tingling or burning.
Deep-vein thrombosis (DVT). DVT is a blood clot that forms in a deep vein of the leg. It can occur when blood flow slows—for example, after surgery, or when you’ve been immobile for many hours on a long car or plane trip. If the clot travels to a lung and becomes lodged there, it’s called a pulmonary embolism—a lifethreatening condition. Symptoms: Swelling and redness in the leg, tenderness. If the clot travels to the lung, symptoms may include shortness of breath, chest pain, and coughing.
Arterial thrombosis. This occurs when a blood clot forms in an artery. If the clot is not treated, the condition may lead to gangrene (with a dark discoloration of the toes or foot). Symptoms: Sudden pain and swelling in one leg, accompanied by discoloration.
Fracture. The force of an accident or weakening due to osteoporosis or cancer can cause a bone to fracture, or break. Fractures range in severity from a simple break in one bone to a shattering in which a bone breaks into multiple pieces or pierces the skin. Symptoms: Pain, swelling and tenderness of the skin over the injury, bruising, deformity, trouble moving or using the injured leg.
