Stress fractures

Stress fractures are tiny cracks in a bone. Stress fractures are caused by the repetitive application of force, often by overuse — such as repeatedly jumping up and down or running long distances. Stress fractures also can arise from normal use of a bone that's been weakened by a condition such as osteoporosis.

Stress fractures are most common in the weight-bearing bones of the lower leg and foot. Track and field athletes are particularly susceptible to stress fractures, but anyone can experience a stress fracture. If you're starting a new exercise program, for example, you may be at risk if you do too much too soon.

Your doctor might diagnose a stress fracture with magnetic resonance imaging (MRI) or another imaging technique. Treatment often involves icing the affected area and plenty of rest. Severe stress fractures may require splinting, casting or surgical insertion of a pin into the bone to promote healing.

# 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

Fatigue fractures. If a normal bone is subjected to overuse or repetitive stress beyond its ability to repair itself, it may crack. This is known as a fatigue fracture. These fractures often occur during high-impact activities such as running and jumping, but they can also occur as a result of prolonged activities such as hiking or walking.