Stress fractures are small cracks in bone that result from repeated applications of force to the body. Think of your bones as shock absorbers, cushioning you from the jarring motions of running, jumping, and other forms of exercise or exertion. Over time, these shocks create hairline breaks in the bones, especially those of the lower legs and feet. Stress fractures are common among physically active people, including athletes and military personnel.

Stress fractures may require treatment by an orthopedic or sports-medicine specialist.

How Do I Know If I Have a Stress Fracture?

Most stress fractures become a source of pain, gradually worsening over time. At first you may feel little more than minor pain or weakness where the fracture is located. Eventually, the pain deepens in conjunction with swelling and tenderness. It may be particularly acute at the site of the break. You might also find that the pain increases with activity and subsides with rest. 

If the pain persists or becomes severe, see your physician. An untreated stress fracture can turn into a more serious break, causing further discomfort and disability, and increasing the likelihood of arthritis.

What Causes Stress Fractures?

Stress fractures have a wide range of potential sources:

• Repetitive motions that cause wear and tear on the body
• Adoption of a new exercise routine or the intensification of an old one
• Poor exercise or training techniques
• Abrupt transitions in walking or running surfaces (soft to hard, flat to steep, even to uneven)
• Non-supportive footwear
• Foot or ankle problems, including tendonitis, bunions, and blisters
• Vitamin deficiencies, especially vitamin D
• Osteoporosis or other bone diseases

Risk Factors for Stress Fractures

Certain risk factors are associated with stress fractures:

• Intensified activity: Increases in physical activity, including exercise and occupational labor, magnify the risk of stress fractures, especially when occurring suddenly.
• High-impact sports: High-impact sports, such as running, basketball, and tennis, are more likely to cause stress fractures than low-impact activities, such as cycling and swimming.
• Physiological problems: Foot problems, ankle issues, and weak or brittle bones make stress fractures more likely.
• Sex: Women are at greater risk for stress fractures than men, due to a higher incidence of osteoporosis and variable aspects of the menstrual cycle.
• Poor diet: Unhealthy eating can short the body of nutrients that encourage strong bones. 
• Past stress fractures: Even with proper healing, your first stress fracture makes you a good candidate for developing more in the future.

How Do I Prevent Stress Fractures?

There are several steps you can take to reduce the probability of stress fractures:

• Eat a healthy diet
• Include low-impact exercises in your workouts
• Transition slowly whenever adding to your exercise regimen
• Wear shoes designed for athletic training and competition

How Are Stress Fractures Diagnosed?

Diagnosis is typically based on a physical examination and medical history. Your physician will want to determine which risk factors are at play, for example, how active you are, what type of work you do, how much exercise you get, the nature of your diet, and so forth.

Imaging technology can be useful in diagnosing a stress fracture. Three common means of imaging the bones are:

• X-rays: X-rays are best at detecting stress fractures once the healing process has begun. A small bump or callus forms at the fracture’s location, which can be rendered visible by an X-ray image. However, X-rays will often not show a stress fracture, causing a need for further imaging to be done.
• Bone scans: Bone scans involve the injection of a tracer, or radioactive chemical, into the body. Some of this chemical will collect at the fracture, turning it darker than the surrounding bone. This makes the fracture easier to see in the X-ray images or CT scans taken by your physician.
• Magnetic resonance imaging (MRI): MRIs are a medical-imaging technology that utilize magnets and radio waves rather than ionizing radiation. MRI scanners provide the clearest pictures of stress fractures among the available imaging technologies.

How Are Stress Fractures Treated?

Like other parts of your body, bones naturally heal themselves. This means the key to treating a stress fracture is typically rest and patience. In addition to taking time off from the physical activity that led to the fracture, you can:

• Apply ice to the point of injury
• Use a walking boot, brace, or crutches to assist in mobility
• Wear only supportive footwear
• Control pain with readily available medications, as needed
• Resume physical activity gradually

Surgery is only rarely required to repair a stress fracture (for example, if blood circulation is poor at the injury site). Orthopedic devices such as screws, pins, or plates can be surgically introduced to strengthen the bone while it heals.  

Complications

Failure to address a stress fracture can lead to more serious health issues over time. The good news is that, with rest and proper care, most stress fractures heal on their own.