A stress fracture in the foot is an incomplete fracture of the bone and most commonly occurs in the metatarsal bones. The metatarsal bones are the five long bones in the foot that form the bridge. A stress fracture occurs because of unusual or repeated stress of the bone, often due to continuous weight or pressure. They are often referred to as hairline fractures.

Oftentimes, stress fractures appear as sports injuries, as bones are continually damaged by exercise. When the body can no longer repair the bone faster than it is stressed during exercise, a weakened site develops which eventually can become a fracture. In other cases, sedentary individuals who undertake large amounts of unusual labor may find that their bones are unable to perform as expected.

This kind of fracture does not present with major symptoms like other fractures. It usually results in localized pain when weight is placed on the foot, and can seem akin to shin splints when the affected individual runs. Occasionally, the area will bruise slightly and will be painful to the touch. Severe pain will continue after pressure is taken off of the bone.

A typical stress fracture will take about four to eight weeks to heal. For the duration, a cast or a walking boot is used to keep weight off of the bone. When the cast or walking boot is removed, an additional six to twelve weeks of rest are recommended. More severe cases may require surgery, but this is uncommon.

Such injuries can be avoided through strengthening exercises and proper diet. By adding more stress to the bones over time, they will become stronger and will be less prone to fractures. This can be done with moderate exercise, especially running. Calcium and Vitamin D also help to strengthen bones, and should be taken as part of a balanced diet.

Hairline fractures are a common injury that occurs due to continual stress on a weakened bone. By strengthening the bone through proper diet and exercise, most hairline fractures can be avoided. When the injury does occur, however, the recovery takes about two months, during which the patient needs to wear a cast or walking boot.