Stress Fracture

Stress fractures are a form of overuse injury, meaning they occur when the foot and ankle are pushed beyond their limits by repetitive activities.

Bones that are commonly affected by stress fractures in the foot include:

  • Calcaneus (heel bone)
  • Talus
  • Navicular
  • Metatarsal (see fifth metatarsal fractures)
  • Sesamoids – tiny disc-shaped bones that sit under the ball of your foot.

Stress fractures are often seen in athletes, especially runners, but may be seen in anyone who suddenly increases their level of activity. They also tend to be more common in people with osteoporosis, or weak bones.

Minor stress fractures will heal very well if the foot is rested. More serious stress fractures may require crutches and a period of non-weight-bearing or reduced activities.

The best advice for stress fractures is to avoid them through well planned training and supportive (even prescription) footwear.

Symptoms

If you have a stress fracture, you may experience:

  • Pain that increases with activity and decreases with rest
  • Pain that occurs earlier in your workout in each successive workout
  • Pain that increases over time
  • Pain that persists even at rest
  • Swelling
  • A specific spot on the involved bone that feels tender or painful to the touch

At first, stress fractures may be barely noticeable. But pay attention to the pain. Proper self-care and treatment can keep the stress fracture from worsening.

When to see your doctor

Stress fractures aren’t always obvious. They develop over time, so it’s difficult to tell exactly when they start to require a doctor’s care. Go to your doctor if running or hurts your foot or leg even after you’ve stopped the activity and given yourself time to rest.

Causes

The most common cause of stress fractures in the foot are repetitive, weight-bearing activities like running, that place the foot under stress.

It’s helpful to remember that bones are living tissue. Unlike plastic or metal, bones are constantly being remade and strengthened. This process is called ‘bone turnover‘ and occurs all the time, especially when you rest at night. Your bones are therefore able to respond to stress and small injuries through self-healing. With high-stress activities like running, tiny microfractures develop along stress lines in the bones. The bone is able to repair itself, however this takes time, and if the stressful activity is repeated frequently or for long periods of time there may be inadequate repair leading to bone fatigue. The microfractures gradually become large before finally becoming a stress fracture.

Events that may precipitate stress fractures:

  • Changes in activity. Increasing the time spent exercising or the frequency of exercise.
    • Changes in the training surface, for example a switch onto concrete can also precipitate stress fractures.
  • Muscle fatigue or injury. The muscles and tendons around your joints keep the stresses on your bones ‘balanced’. This is especially true in the foot, which is specially designed so that your weight is rolled from heel to toe in a fluid manner. An injury or weakness in a muscle group can lead to unbalanced stresses and bone fatigue.
  • Deficiencies in nutrition and minerals, especially in calcium, vitamin D (found in sunlight) and iron.

Risk Factors

You may be at increased risk of stress fractures if you:

  • Are an athlete who participates in high-impact sports such as track and field, basketball, tennis or gymnastics.
  • Are a female athlete with abnormal or absent periods.
    • Irregular or absent periods can indicate low BMI or nutrition, and may suggest that the female hormone oestrogen is inadequate to protect bones.
  • Suddenly shift from a sedentary lifestyle to an active training regimen — such as a military recruit subjected to intense marching exercises — or rapidly increase your exercise length and intensity
  • Have flat feet (see flatfoot deformity) or high, rigid arches
  • Have osteoporosis or other conditions that lead to weakened bones or decreased bone density

Investigations

X-Rays can be used to help diagnose stress fractures, however they may not be sensitive enough to pick up subtle fractures in the first two to three weeks after an injury.

An MRI or bone scan can also be used to diagnose a stress fracture.

If your doctor suspects an underlying cause for your stress fracture, you may need to have some blood tests.

Complications

If stress fractures are not allowed to heal they can persist, resulting in chronic pain.

Long-term, there is an increased risk of arthritis developing in the foot or ankle later in life.

Treatment

Treatment varies depending on the location of the stress fracture and on how quickly you need to resume activity.

Medications

If needed, take Paracetamol to relieve pain. Some research suggests that non-steroidal anti-inflammatory pain relievers (NSAIDs) — such as aspirin, ibuprofen, naprogesic etc — can interfere with bone healing. Your pharmacist can advise you which drugs fall into this category.

If you are female and have had long-standing irregular periods your GP may discuss the need to put you on the oral contraceptive pill. This is designed to help you return to a normal menstrual pattern and thus strengthen your bones.

Therapies

To reduce the bone’s weight-bearing load until healing occurs, you may need to wear a walking boot or brace, or use crutches.

In severe cases, the doctor may need to immobilise the affected bone with a splint or cast. Although it’s unusual, surgery is sometimes necessary to ensure complete healing of some types of stress fractures, especially those that occur in areas with a poor blood supply.

Looking After Yourself

It’s important to give the bone time to heal. This may take four to 12 weeks or even longer. In the meantime:

  • Rest. Stay off the affected limb as directed by your doctor until you are cleared to bear normal weight.
  • Ice. To reduce swelling and relieve pain, your doctor may recommend applying ice packs to the injured area as needed — up to three to four times a day for 10 minutes at a time.
  • Resume activity slowly. When your doctor gives the OK, slowly progress from non-weight-bearing activities — such as swimming — to your usual activities. Return to high impact activities, such as running, on a gradual basis, with careful progression of time and distance.

Seeking Advice

You should seek advice from your local GP when

  • Symptoms of pain or swelling are severe and/or persist after you’ve stopped exercising
  • You have infrequent or absent periods

Your Family Doctor will be able to diagnose and help treat your problem. He or she will be able to

  • tell you about your problem
  • advise you of the best treatment methods
  • prescribe you medications
  • and if necessary, refer you to Specialists (Consultants) for further treatment.

You’re likely to start by first seeing your family doctor or a general practitioner, but if you’re a competitive athlete, you might go directly to an orthopaedic surgeon or other sports physician who is a specialist in musculoskeletal problems. The doctor will want to know:

  • When your symptoms started
  • What pattern your symptoms occur in — at certain times, during or after certain activities or continuously
  • What sports and activities you normally do, and whether a change in your routine coincided with the start of your symptoms

Prevention

Simple steps can help you prevent stress fractures.

  • Start any new exercise program slowly, and progress gradually. Don’t exercise too hard or too long.
  • Avoid sudden changes in intensity or type of exercise.
  • Use proper equipment and footwear appropriate for your activity.
  • Cross-train with low impact activities to avoid repetitively stressing a particular part of your body.
  • If you have flat feet, ask your doctor about arch supports for your shoes.

Nutrition counts, too. To keep your bones strong, make sure your diet includes plenty of calcium (found in dairy products and calcium-fortified foods, eg bread) and other nutrients.

Being aware of how your feet and ankles feel. If you do notice pain try to rest your feet by either avoiding sports completely or avoiding those high-impact activities that may exacerbate your injury. You may need to rest for several days to a couple of weeks to give your bones adequate time to heal.

F.A.Q. | Frequently Asked Questions