Doctors can sometimes diagnose a stress fracture from a medical history and a physical exam, but imaging tests are often needed.
- X-rays. Stress fractures often aren't apparent on regular X-rays taken shortly after your pain begins. It can take several weeks — and sometimes longer than a month — for evidence of stress fractures to show on X-rays.
- Bone scan. A few hours before a bone scan, you'll receive a small dose of radioactive material through an intravenous line. The radioactive substance accumulates most in areas where bones are being repaired — showing up on the scan image as a bright white spot. However, many types of bone problems look alike on bone scans, so the test isn't specific for stress fractures.
- Magnetic resonance imaging (MRI). An MRI uses radio waves and a strong magnetic field to produce detailed images of your internal structures. An MRI usually can visualize stress fractures within the first week of injury, and can visualize lower-grade stress injuries (stress reactions) before an x-ray shows changes. This type of test is also better able to distinguish between stress fractures and soft tissue injuries.