Stress Fractures of the Foot

A stress fracture refers to thin cracks in the bones, also called hairline fractures. These fractures mostly affect the weight-bearing bones and occur as a result of repeated or excessive stress, as opposed to regular fractures that result from a single severe impact.

In the foot the most common sites of stress fractures are the metatarsal bones, which are five small bones located in the mid part of the foot. Mostly, the second and third metatarsals are involved, in addition the heel bone (calcaneus) and navicular bone (a small bone located in front of the inner part of the ankle) may also be involved.

Cause:

A stress fracture is categorised as an overuse injury. Whenever the body is subjected to unusual stresses or to the usual stresses to an unusually excessive degree, the muscles become tired and less flexible. As muscles are attached to bones, when they become stiff they lose their ability to absorb the shock of the impact, which is then transferred to the bones.

The resulting bone trauma usually heals as a result of the normal regenerating capacity of the bones, however this requires a sufficient recovery period. When the bones are exposed to repeated stress without giving them time to recover, the continued trauma results in a stress fracture. It is an incomplete fracture, which weakens the bone and, when left untreated, may lead to a complete fracture.

Contributing Factors:

  • Increasing the mileage too rapidly when running
  • Changing to a more intense exercise without proper conditioning of the body
  • Altered biomechanics of the lower limb due to tendonitis, bunions, or any such condition that disturbs the normal weight distribution pattern and puts excessive stress on a specific bone
  • Wearing stiff or worn-out shoes that do not support the feet properly, or transferring from grassy field to concrete floors
  • Conditions that affect the strength of the bone such as osteoporosis.

Female athletes are more prone to developing stress fractures as a result of osteoporosis, irregular menstrual cycles and eating disorders that all weaken the bones.

Athletes, especially runners, gymnasts, and players of other high impact sports such as basketball, volley ball, tennis, etc, dancers and military people are all at increased risk of developing stress fractures of the foot. Stress fractures are also common in less active people who suddenly take on a vigorous exercise regime.

Symptoms:

  • Initially there is pain, which appears gradually, intensifies with activity and is relieved with rest.
  • As the metatarsals are mostly involved, pain usually occurs on the top of the foot or on the outside of the ankle when the heel bone is involved.
  • Without treatment, pain becomes constant and severe and persists even at rest
  • The area becomes tender and may also swell

Diagnosis:

The symptoms and history are important in diagnosing the condition. Stress fractures cannot be located easily on X-rays; an MRI or a bone scan is usually advised.

Treatment:

In the initial stages, the best treatment is to give the bone sufficient time to rest. Do not ignore the pain. The more you delay the treatment the more delayed will be the healing.

– if you suspect a stress fracture, immediately stop whatever activity is causing the pain

– apply an ice pack and elevate the foot above your heart level to help control the swelling and pain

– consult a physician soon as possible

– control any over-pronation of the foot with an insole