Stress Fractures of the Foot & Ankle
What is a stress fracture?
A stress fracture is a small crack in the bone which occurs due to overuse. They most commonly occur in the weight bearing bones of the lower leg and foot. When the bones are subjected to abnormal stress, such as an increase in activity or a new exercise regime, they may not be well adapted to the new forces, and they can crack under the new stresses.
What causes a stress fracture?
Stress fractures are usually caused by a rapid increase in the intensity of exercise. They can also be caused by impact on a hard surface, improper footwear, and increased physical activity. Athletes participating in certain sports such as basketball, tennis, gymnastics and running are at a greater risk of developing stress fractures. During these sports the repetitive stress of the foot strike on a hard surface causes trauma and muscle fatigue. An athlete with inadequate rest between workouts can also develop stress fractures.
Females are at a greater risk of developing stress fractures than males, and this may be related to a condition referred to as the "female athletic triad". It is a combination of eating disorders, amenorrhea (irregular menstrual cycle), and osteoporosis (thinning of the bones). The risk of developing a stress fracture increases in females if the bone density decreases.
What symptoms does a stress fracture cause?
The most common symptom is pain in the foot, which usually gets worse during exercise and decreases with rest. Swelling, bruising, and tenderness may also occur at a specific point.
How is a stress fracture diagnosed?
The diagnosis is usually made based on history and physical examination. X-rays are required, but these can be normal if you’ve only had the symptoms for a short time. Additional tests like MRI, CT or bone scan can then be required in this case.
What are the treatment options?
Stress fractures are initially treated by stopping the aggravating exercise, which usually means rest and time away from sport for 6-8 weeks. Non-impact activities like swimming and exercise bike can sometimes continue.
If children return too quickly to the activity that has caused stress fracture, it may lead to chronic problems such as harder-to-heal stress fractures. Re-injury can also occur without allowing the stress fracture to completely heal.
Protective footwear may be recommended which helps to reduce stress on the foot. A stiff soled surgical shoe or a walking boot may form part of the treatment. In certain cases, a cast may be recommended to immobilise the leg and foot. Crutches may be used to prevent weight going through the foot until the stress fracture is healed completely. Calcium and Vitamin D supplements are also often prescribed.
Surgery may be required if the fracture is not healed completely by non-surgical treatment. This is called a non-union. Surgery involves placing bone graft in the non-union site, and then placing screws or plates to compress the fracture and hold it together.
The most common complication is that the stress fracture does not heal (non-union). Other complications include the bone healing in an abnormal position (malunion), and recurrent stress fractures. If osteoporosis is the cause of recurrent or multiple stress fractures, review by an endocrinologist and medications are often required.
How can stress fractures be prevented?
Some of the following measures may help to prevent stress fractures:
- Ensure to start any new sport activity slowly and progress gradually, particularly after a period of inactivity.
- Increase running or walking speed and distance gradually, in increments of no more than 10% per week.
- Cross-training: You may use more than one exercise with the same intention to prevent injury. For example, you may run on even days and ride a bike on odd days, instead of running every day to reduce the risk of injury from overuse. This limits the stress occurring on specific muscles as different activities use muscles in different ways.
- Ensure you maintain a healthy diet and include calcium and vitamin D-rich foods in your intake.
- Ensure that you or your child uses proper footwear or shoes for any sports activity and avoid using old or worn out shoes.
- If your child complains of pain and swelling, then immediately stop the activities and make sure that your child rests for few days.