What is a possible occult fracture?

A fracture is a broken bone. Occult means hidden. An occult fracture does not appear well on an X-ray. A possible occult fracture is a suspected fracture that needs to be confirmed with other imaging tests.

Occult fractures can occur because of a fall or other type of sudden (acute) injury. They can also occur because of repetitive injuries or normal stresses on weak bones. Fractures caused by repetitive injuries are fatigue fractures. Those that result from normal stresses on weak bones are insufficiency fractures. Another name for these fractures is stress fractures.

Common sites for occult fractures include the hip, shin, upper arm, and the bones of the ankle, foot, wrist, and spine. Stress fractures are more common in the lower part of the body than in the upper part. They are also more common in women than in men. They often occur in athletes and military recruits.

What causes a possible occult fracture?

Accidents, such as falls, cause some occult fractures. The rest are caused by repetitive activities or weakened bones.

Repetitive activities, such as running, marching, and throwing, can cause fatigue fractures. These injuries often occur in people who suddenly increase their activity level. Their actions cause tiny cracks in the bone. Normally, the bone is able to repair these small fractures. But that needs time. When the activity continues or happens again before the repairs are complete, these small fractures can add up to form a stress fracture. In extreme cases, ongoing activities can cause sudden larger fractures.

Insufficiency fractures occur in weak bones. Bones can weaken enough that they can't withstand normal stresses caused by walking, twisting, or other low-impact activities. Causes of weak bones include:

  • Bone loss (osteoporosis)
  • Genetic disorders, such as osteogenesis imperfecta
  • Rheumatoid arthritis
  • Bone tumors
  • Exposure to radiation or chemotherapy
  • Long-term steroid use
  • Infection
  • Kidney disease

Who is at risk for a possible occult fracture?

You may have an increased risk for occult fractures if you:

  • Have a condition that weakens bones
  • Are not physically fit
  • Are a military recruit
  • Engage in certain athletic activities

Sports that raise the risk for leg, ankle, and foot fatigue fractures include long-distance running, track and field, basketball, football, soccer, and dance. Fatigue fractures of the spine are more common in gymnasts, volleyball players, football players, dancers, and cheerleaders. Shoulder and arm fatigue fractures can occur in pitchers, cheerleaders, and gymnasts.

Other things that can raise your risk include:

  • Being assigned female at birth
  • Abnormal menstrual periods or no period
  • Poor nutrition or eating disorders
  • Chronic cough
  • High arches or flat feet
  • Previous stress fractures
  • Smoking
  • Having more than 10 alcoholic drinks a week

What are the symptoms of a possible occult fracture?

The most common symptom of an occult fracture is pain. You may notice that the pain gets worse with activities and improves with rest. Even walking or just putting weight on your leg may cause pain. If you have an occult fracture of your hip, you may not be able to walk. Occult fractures often cause pain in a specific area, rather than pain that is widespread. You may feel a sudden increase in your pain if you develop a larger fracture after continuing to put stress on the bone.

How is a possible occult fracture diagnosed?

Your healthcare provider will ask about your recent symptoms and your past health. On exam, they may note a specific area of tenderness, pain with certain movements, and swelling.

Your healthcare provider will send you for X-rays. The X-rays can show any sign of a broken bone. If they look normal despite a suspected fracture, you may need repeat X-rays in about 2 weeks or other imaging tests. These may include:

  • MRI
  • CT scan
  • Bone scan (bone scintigraphy)
  • Ultrasound

Occult fractures often show up on MRI scans. But MRIs are expensive. They may also take longer than other imaging tests. And they are not available everywhere. You may not be able to have an MRI if you have a pacemaker.

Newer CT scans are an alternative to MRI scans. They are often a good choice when you can't have an MRI scan. Before the newer CT scans, healthcare providers often used bone scans. Occult fractures often show up on bone scans. But it's hard to find their exact location. Ultrasound is another choice. The provider can quickly do a scan with ultrasound.

How is a possible occult fracture treated?

The treatment of an occult fracture depends on where it is. Sometimes the combination of rest with splinting or casting is enough. If you have an occult fracture of your leg, ankle, or foot, you may need to use crutches to keep all of your weight off your injury. Or you can use crutches to limit the amount of weight you put on it. You may also need to wear a walking cast or boot as it heals.

Your healthcare provider may refer you to a sports medicine specialist for treatment. Or they may refer you to a provider specializing in bones, muscles, and joints (an orthopedist). That’s especially the case if you have an occult fracture of the spine, hip, lower leg, ankle, or foot. Sometimes occult fractures need to be treated with surgery. The bone can then be fixed with pins, screws, or metal plates.

Bones heal through a process of knitting. Cells within the bone lay down new bone building blocks and remodel them until the bones become reconnected and strengthened. This healing process may take a few weeks to a few months. Even after the bones have started to heal, it may still be some time before they can handle the stresses they used to.

When you have your cast or splint removed, you will likely find that your muscles are weaker than they used to be. Once it's OK to resume activities, your healthcare provider may send you to rehabilitation specialists. They can help you learn exercises to rebuild your strength and flexibility and to prevent future fractures.

What are possible complications of a possible occult fracture?

If your fracture is not diagnosed promptly and treated, the bone may not heal correctly. Sometimes complications occur even after correct treatment. Possible complications of an occult fracture include:

  • Chronic pain
  • Osteoarthritis
  • Death of bone because of decreased blood supply (avascular necrosis)
  • Disability

What can I do to prevent a possible occult fracture?

Accidents happen, but you can take certain precautions to lower your risk for accidents and of injuries from accidents. You can also take precautions to reduce your risk for stress fractures. Here are some things you can do to lower your risk:

  • Eat a healthy diet that is rich in calcium and vitamin D.
  • Wear correctly fitting shoes with cushioned insoles. Replace them every 3 to 6 months.
  • Increase your activity level slowly and take rest breaks.
  • Cross-train and do strengthening exercises.
  • If you have a risk of falling, install safety bars in your home.
  • Remove tripping hazards.
  • If you have a condition that weakens bones, talk with your healthcare provider about ways to strengthen them.

When should I call my healthcare provider?

Call your healthcare provider if you:

  • Have pain with activity that doesn't go away
  • Have ongoing pain after an injury
  • Have a sudden increase in your pain

Key points about a possible occult fracture

  • A possible occult fracture is a suspected broken bone that doesn't show up on X-rays.
  • Accidents, repetitive injuries, and normal stresses on weak bones can all cause occult fractures.
  • The pain from occult fractures gets worse with activity.
  • MRI is one of the best tools for diagnosing occult fractures. But it is not always a choice.
  • Rest can help prevent and treat occult fractures.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

  • Know the reason for your visit and what you want to happen.
  • Before your visit, write down questions you want answered.
  • Bring someone with you to help you ask questions and remember what your provider tells you.
  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new directions your provider gives you.
  • Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
  • Ask if your condition can be treated in other ways.
  • Know why a test or procedure is recommended and what the results could mean.
  • Know what to expect if you do not take the medicine or have the test or procedure.
  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your provider if you have questions.