A stress fracture is a small crack in a bone caused by overuse and high impact.
A stress fracture results from repetitive use injuries that exceed the ability of the bone to repair itself. Impact forces are transferred to the bones, causing microfractures that consolidate into stress fractures. Stress fractures occur in weight-bearing areas, commonly the lower leg (tibia) and foot (metatarsals).
Most stress fractures result from a rapid increase in the amount or intensity of exercise.
Sports involving running or jumping place individuals at highest risk. Such sports include track and field, basketball, tennis, ballet, and gymnastics.
Upper extremity stress fractures, though much less common than lower extremity stress fractures, can be caused by repetitive use of the arms (eg, baseball, tennis).
Women are more likely than men to develop stress fractures. Women with irregular or absent periods are at particularly high risk.
About 60% of persons with a stress fracture have had a previous stress fracture.
Dull, localized bone pain not associated with trauma that worsens with weight bearing or repetitive use. Localized swelling may occur at the pain site, which hurts to touch.
Doctors usually make the diagnosis based on a patient’s story and physical exam. Early stress fractures are usually not visible on x-ray. The diagnosis may be confirmed with magnetic resonance imaging (MRI) or a bone scan. An MRI uses a large magnet to produce a high-resolution picture of bones and soft tissue. A bone scan involves injection of a small amount of radioactive material which tends to pool at fracture sites. The fracture then appears as a “hot spot” on a picture by a radiation-sensitive camera.
Stress fractures heal with time and rest. Athletes are advised to rest from any activity that caused the stress fracture for the 6-14 weeks that the fractures take to heal (ask your doctor how long your particular fracture will probably take to heal), or until pain-free for 2-3 weeks. If activity is resumed too quickly, a larger stress fracture may develop, the original stress fracture may never heal, and athletes are at risk for re-injury. Activities of daily living and limited walking are permitted.
Ice and nonsteroidal anti-inflammatory drugs (eg, ibuprofen, naproxen) can decrease pain and swelling. Calcium and vitamin D supplements may also be helpful.
Substitution of a non-weight-bearing exercise, such as swimming, can prevent cardiovascular deconditioning.
Air splinting may help to speed recovery and reduce pain in severe or non-healing lower leg fractures. Other types of fractures occasionally require special shoes, casting or surgery. Ask your doctor which therapies are right for you.
If you have recurrent stress fractures, your doctor may advise an imaging test that assesses bone density.
High-impact exercises should be increased gradually (not more than 10% per week). Athletes should stretch and warm-up appropriately before exercise. Using well-cushioned shoes in good condition can help prevent fractures. Ask your doctor if arch supports or orthotics are appropriate for your foot structure.
Runners benefit from running on smooth, level surfaces.
Maintain adequate intake of calcium, a mineral found in bones, to have strong, healthy bones.
If you notice any pain or swelling during physical activity, refrain from that activity for a few days. Consult a physician if the pain does not improve.