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US Pharm. 2012;37(10):17-18.
Small Crack in a Bone
A stress fracture is a minute crack in a bone, usually located in a
lower limb, that is caused by a change in the force load on that limb.
Most stress fractures occur after an increase in repetitive trauma on a
weight-bearing bone in the lower leg or foot. Stress fractures are
commonly seen in runners, tennis players, gymnasts, dancers, and
basketball players. Stress fractures in athletes may result from an
increase in the amount or intensity of an activity; they also may be
caused by increased surface impact due to loss of cushioning in the shoe
or playing surface.
The primary symptom of stress fracture is local pain at the fracture
site that is relieved by rest. Diagnosis is made by taking a history of
recent activity and a symptom history. In some cases, imaging studies
are used to confirm the diagnosis.
The most effective treatment for stress fractures is rest. The
fracture site must be protected from activity for a minimum of 6 to 8
weeks to permit complete healing. During this period, the patient can
perform alternative exercises to remain active. In some cases, shoe
inserts or braces can help immobilize and support the area and enhance
the healing process. The recommended rest period must be maintained for
the full duration; early or continued activity involving the injured
limb can lead to complications that may require orthopedic surgery. Once
a stress fracture is completely healed, a regimen of flexibility,
strength training, and variation in fitness activities is typically
recommended to prevent the development of stress fractures in the
future.
The Most Common Cause of Injury Is Running
Although stress fractures—tiny cracks in the bone—are an occupational
hazard for professional athletes, they can develop in anyone who is
beginning a new activity or has weakened bones from osteoporosis or a
poor diet. These fractures most often occur in the lower limbs and feet,
but they can develop in the spine and ribs (in sports such as
gymnastics) and in the bones of the upper body (in sports causing
repetitive movement in that area, such as tennis).
Causes, Symptoms, and Diagnosis
The most common cause of stress fractures is running, which leads to
repetitive stress on the bones of the leg and foot. When the weight load
is greater than the bone’s ability to handle this stress, small cracks
can appear in the bone. This is especially true when there is a change
in the amount or intensity of the activity or in the cushioning of the
shoe or surface used for the activity.
Women may be more susceptible to stress fractures because of weaker
bone mass. The “female athlete triad”—a condition that includes an
eating disorder such as anorexia, irregular or no menstrual periods, and
osteoporosis—can predispose women to stress fractures.
The primary symptom of a stress fracture is the gradual onset of pain
during a particular activity. The pain increases as the activity
continues and is relieved by rest. With each exercise session, the pain
may begin earlier in the workout. There may be tenderness at the point
of fracture, with possible redness and swelling.
Often, the diagnosis is made by evaluating the history of the pain in
relation to activity, as well as any changes in the amount or intensity
of the activity or playing surface. These tiny cracks in the bone
cannot be seen on a typical x-ray image, especially soon after the
fracture occurs. If needed, another imaging procedure, such as a
computed tomography scan or magnetic resonance imaging, may be used to
confirm the diagnosis.
Treatment and Prevention
The treatment of stress fractures involves a rest period from the
activity that likely caused the fracture. Depending upon the location of
the fracture, healing can be facilitated by stabilizing the bone with a
brace or shoe insert. Other forms of activity, such as swimming and
cycling, may be performed. Ice compresses may be used to reduce
swelling. Acetaminophen or nonsteroidal anti-inflammatory drugs are
useful initially to relieve pain, but the pain is best relieved with
rest.
Most stress fractures heal completely with appropriate treatment. If
activity is resumed too early, inadequate healing or re-injury can
occur. These complications can lead to chronic pain and bone weakness,
so it is important never to ignore stress fractures by continuing the
activity that caused the problem.
It is especially important to correct any element that may have been
involved in causing the stress fracture. This includes not only limiting
weight-bearing activity on the affected bone, but also using proper
shoes and athletic surfaces. Any factor that could contribute to
weakened bone, such as osteoporosis, should be treated if it was present
when the fracture occurred.
Stress fractures can be prevented by slowly building up time and
intensity level in any athletic activity. Appropriate supportive
athletic shoes, as well as the right playing surface, should be used. A
diet that promotes strong bones is another important means of
prevention. Any activity that causes pain should be discontinued until
it can be performed without discomfort.
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