Stress Fractures of the Foot and Ankle
What is a stress fracture?
A stress fracture is a tiny crack, or multiple tiny cracks, in the bone of the foot or ankle. Most stress fractures are caused by overuse and repetitive stress which results in microscopic injuries to the bone. Unlike traumatic fractures, stress fractures are due to constant moderate force occurring frequently and over time. While they may sound harmless, in fact, these injuries cause pain, permanent disability, and loss of playing time.
Stress fractures can affect all types of bones but are more common in bones that support bodyweight, because they are under constant pressure from standing walking, running and jumping.
Which bones in the foot an ankle are commonly affected?
Stress fractures are common in the foot especially in the metatarsal bones of the foot and the heel bone (calcaneus). Stress fractures of the heel bone involve multiple incomplete breaks in the bone, caused by repetitive stress.
The metatarsals are a group of five long bones in the foot that connect the toes to the midfoot. In the ankle, the most commonly affected bones are the navicular bone and ends of the tibia and fibula in the ankle joint.
What causes stress fractures?
Stress fractures are a sports injury that affects about 40% of athletes at some time during their careers. They account for up to 10% of all orthopedic injuries and are about 13% higher in female athletes.
Repetitive stress on healthy bones cause stress fractures as are often seen in high impact sports such as running, ballet, jogging, aerobics, tennis, soccer, gymnastics, volleyball, and basketball.
Repetitive stress on weak bones can cause a stress fracture with normal everyday activities.
Stress fractures of the foot and ankle are increasing in post-menopausal women with osteoporosis.
Female athletes are at increased risk partly due to low bone density caused by eating disorders, excessive exercise, menstrual dysfunction and osteopenia. This is called the “female athlete triad”.
What are the risk factors?
The risk for stress fractures tends increase when:
- trying out a new exercise
- undertaking a new exercise without proper training and conditioning and/or poor technique
- suddenly increasing the amount, intensity, duration or frequency of physical activity
- wearing unsupportive or worn out athletic shoes and using worn out equipment
- wearing shoes with poor support like heels
- people with flat feet or bunions change the load bearing
- changing the workout surface from a treadmill to cement or walking or running on uneven surfaces.
- conditions that decrease bone mineral density like osteoporosis, or low Vitamin D3, and some long-term medications increase the risk of stress fractures. When bone strength and density are compromised, everyday activity can be enough to cause a stress fracture.
What are the symptoms of a stress fracture?
- Pain in the affected bone
- Pain with normal activity and when pressure is applied
- Pain that lessens with rest
- Pain that disappears when the activity is stopped and reappears during activity
- Swelling on the top of the foot or outside of the ankle.
How is a stress fracture diagnosed?
Your OANC orthopedist will review your medical, discuss your symptoms and when they occur, and conduct a physical exam applying gentle pressure on the injured area. X-rays may not be able to detect stress fractures until they begin to heal. Therefore, your doctor may recommend a bone scan or MRI to show the location of a stress fracture.