Stress fracture (also called a fatigue fracture)
is a weakening or thin crack in a bone caused by repetitive stress on the bone.
A stress fracture is an overuse injury. It is different from a fracture that
occurs after a traumatic event, such as a fall. Stress fractures are more common
in endurance athletes or athletes who perform repetitive, high-impact
Risk factors for stress fractures
With sufficient levels of stress to a bone,
anyone can develop a stress fracture. However, there are additional risk factors
related to the individual and to the training pattern that can further increase
the risk of developing a stress fracture.
Individual risk factors
Inadequate caloric intake;
inadequate calcium intake.
Low estrogen levels in females;
Low body weight; rapid weight
Ethnicity. White athletes may be at
Biomechanical abnormalities. A
high-arched foot is more rigid and transmits more stress to the
bone; a flat foot causes greater demands and fatigue of protective
muscles resulting in less shock absorption by the muscles.
Prior stress fracture. This is a
risk because it may include a combination of many of the other risk
Training risk factors
Too much, too soon, too fast. An
overly rapid increase in activity—particularly high-impact
activity—does not allow adequate time for the bones to adapt
to the increased levels of stress.
Hard surfaces. Running and jumping
on roads; concrete; hard gym floors; or dry, compacted, hard fields
can increase the risk of stress fracture—particularly if the
athlete isn't used to training on such surfaces.
Inadequate footwear. The
shock-absorbing capacity of shoes will diminish even before the shoe
appears worn out. Some foot types require more support than is
provided by the shoe they use for the sport, and some foot types
require more cushion. This is particularly true with cleated shoes,
which generally have limited arch support and cushion.
The main symptom of a stress fracture is pain in
the bone that is slow to develop, gets worse with impact activity, and subsides
with rest. With continued activity, the pain becomes much more sharp, localized,
and persistent. Occasionally, a bump over the area can be felt. A limp may also
be an indicator of a stress fracture.
Common locations for stress fractures include
the tibia (shin bone), fibula (bone on the outer portion of the lower leg) and
metatarsals (bones in the forefoot). Stress fractures less commonly occur in the
femur (thigh bone), pelvis, spine, and upper extremity. Suspicion of a stress
fracture warrants checking with your doctor. Bone pain from other causes, such
as bone cysts, infection, and tumors, must also be ruled out.
To confirm the presence of a stress fracture,
your doctor may need to order an x-ray (see Figure 1). If the x-ray does not
show a stress fracture, a bone scan (see Figure 2) or magnetic resonance imaging
(MRI) may be needed.
During the first phase of treatment, it is
usually enough for athletes to limit impact activity. Some stress fractures may
require casting, crutches, or surgery. Most athletes are able to continue to
lift weights, swim, ride a bike, or use an elliptical trainer as long as there
is no pain. Ice, acetaminophen, and rest are the main treatments for pain. In
general, nonsteroidal anti-inflammatory drugs (NSAIDs), like ibuprofen and
naproxen, are not recommended because they may delay healing. Biomechanical,
nutritional, and menstrual problems must be addressed during the treatment to
help the athlete heal. This can help prevent future stress fractures from
Healing time depends on the athlete's
age, how long the fracture has been present, which bone is involved, and the
condition of the bone. The time frame for healing is usually weeks to months. It
is crucial for athletes with stress fractures to be followed by a doctor to
monitor healing and approve a level of activity that is safe for the level of
healing that is present.
Complete healing may be documented by the
resolution of bone tenderness and evidence of healing on x-ray. Once your doctor
has determined that the bone has sufficiently healed, running and jumping
activities may be gradually reintroduced. The final stage is to incrementally
return to play with practice sessions, scrimmages and, finally, games or
Ask your doctor how to avoid stress fractures
during your preparticipation exam or annual physical. You may discuss nutrition,
exercise guidelines, appropriate footwear, and supplements (like vitamin D and
calcium). If there are any other risk factors, such as menstrual irregularities
in female athletes, this can be further evaluated and treated—before a
stress fracture develops. Being aware of the early warning signs of a stress
fracture can also help reduce injuries.