Synonyms and Keywords
Ankle stress fracture, back stress fracture, calcaneus stress fracture, fatigue fracture, femoral neck stress fracture, femur stress fracture, fibula stress fracture, foot stress fracture, hairline fracture, heel stress fracture, hip stress fracture, knee stress fracture, lower leg stress fracture, metatarsal stress fracture, navicular stress fracture, pars stress fracture, pelvic stress fracture, pubic rami stress fracture, sacral stress fracture, sacrum stress fracture, shin splint, stress fracture medial malleolus, stress fracture symptoms, tibia stress fracture.
What is a Stress Fracture?
If you are a track and field athlete, you’re likely familiar with stress fracture. It is a tiny crack in a bone, usually in the weight-bearing bones of the lower leg and foot, like the tibia (bone of the lower leg) and metatarsals (foot bones). Whereas regular fractures involve major trauma or force like a car crash to break a bone, stress fractures come from a much lighter impact, but occurring repetitively for a much longer period of time. The muscles surrounding the bones become so worn down, fatigued, or overloaded from the constant pounding, they cannot absorb the shock completely and transfer the stress to a nearby bone, causing it to slowly crack. The crack could be so fine that sometimes it is called a “hairline fracture.”
A stress fracture is a common overuse injury most often seen in athletes, stemming from repeated impact or pressure on “overused” muscles. It rarely occurs in the upper extremity because the weight of your body is not supported by your arms as it is in your legs. As a result, these “fatigue fractures” often plague those who run and jump on hard surfaces regularly, such as distance runners, basketball players, and ballet dancers.
What Causes a Stress Fracture?
When most people think of a broken bone, they picture an incident where the bone takes a lot of force directly at once and breaks. A stress fracture, however, is quite the opposite. The impact is not significant but persistent. The cumulative force built up over time eventually tires out the muscles like water running over rocks and eroding them piece by piece. Naturally, weakened muscles cannot absorb stress like strong or even normal ones, so a neighboring bone has to pick up the slack and begin taking the pressure more and more for the muscles. Since the traumas add up and a bone can only take so much, it eventually cracks from the excess stress.
Repetitive application of force, such as repeatedly jumping up and down or running long distances, is the primary culprit for stress fractures. Certain fractures are more sports-specific: runners tend to develop stress fractures of the tibia (shin bone), tennis and basketball players often injure the navicular bone in the foot, etc.
In addition to muscle fatigue, the constant impact forces bones to lose cells. Because you only add new bone cells when you’re at rest, without sufficient time for recovery you’ll be losing bone cells faster than you can replace them. As a result, you develop “bone fatigue,” impairing the bones’ ability to repair the tiny chips and cracks of a stress fracture that start to form.
Not wearing the properly cushioned footwear or adequate equipment capable of absorbing shock can obviously lead to stress fractures, as the feet are not protected from impact. Increasing the time, type, or intensity of a physical activity too much, too soon is another cause, when the muscles and bones simply cannot handle the greater demand.
Dietary abnormalities and menstrual irregularities can contribute to the development of a stress fracture, too. Because both factors are relevant to bone health, any problems with diet (for example, poor nutrition, anorexia, bulimia) or menstruation (amenorrhea) can cause this type of injuries. A bone that’s been weakened by a condition such as osteoporosis (thinning of the bones) may not be able to endure even normal physical tasks, and thus a prospect for stress fracture.
Who Gets a Stress Fracture?
Stress fractures happen when the lower extremities of the body are overburdened. This includes the bones of the feet, shin, thigh, and pelvis. For that reason, the injury usually affects those who engage in an extraordinary amount of high-impact exercise (e.g., Olympic-class athletes), sports or activities requiring quick movements (basketball, soccer, tennis, gymnastics, ballet), distance running with high weekly mileage, and long marches (like military soldiers). People who sit a lot or are inactive can be prone to the condition as well when they suddenly undertake a flurry of exercise.
Body design is also a concern: The taller or heavier you are, the more force your legs have to absorb; improper muscle or bone alignment from the back to the feet decreases the bones’ ability to mitigate impact; weak muscles will absorb less force and thus heighten the stress transferred to the bones; weak bones will not accept the pressure well.
Age is certainly a factor, as bone mineral density declines as we become old.
Because of the increased potential for osteoporosis in women, they are twice as likely as men to sustain a stress fracture. This may be rooted in the combination of poor nutrition, eating disorders and infrequent menstrual cycle called the “female athlete triad,” which predisposes women to early osteoporosis.
Previous stress fractures have been identified as a risk factor. If you don’t let a prior injury heal completely, you’re especially susceptible to getting it again.
People who have flat feet or high, rigid arches are more likely to develop stress fractures from the abnormal walking/running motion that puts additional pressure on the bones.
Those of African descent are less likely to suffer stress fractures when compared with Caucasians, due to a generally higher bone mineral density.
Are There Different Types of a Stress Fracture?
Stress fractures are typically differentiated by the affected location:
- Metatarsal bones of the foot
- Navicular bone in the foot
- Calcaneus (heel bone)
- Tibia (shin bone)
- Fibula (calf bone)
- Femur (thigh bone)
- Femoral neck in the hip
- Pubic rami of the pelvis
- Pars articularis of the lumbar spine
What are the Symptoms of a Stress Fracture?
Stress fractures usually have only a few symptoms. The signs include:
- Pain. This is the primary sign of a broken bone. Pain often begins toward the end of an activity and stops with rest. If the injury or symptoms are ignored, the pain will begin earlier during the exercise and continue even after completion. Eventually, the pain will become persistent with minimal activity. Pain at night is a common complaint
- Swelling at the injured region
- Tenderness in a specific spot when it’s touched
How do You Diagnose a Stress Fracture?
A stress fracture is almost impossible to diagnose on your own since the break is miniscule and all you may experience is pain. Hence, physical examination by a medical professional is important. During the exam, you doctor will ask about your symptoms, level of physical activity, and general health. He/she will press on the bones and soft tissues around the site of your pain, trying to pinpoint what exactly has been injured.
X-rays usually do not show a stress fracture, but may reveal evidence of bone attempting to heal around the injury. Bone scan or MRI (magnetic resonance imaging may be more effective in unclear cases.
How do You Treat a Stress Fracture?
The best treatment is almost always resting the injured leg. If there is no evidence that the stress fracture may shift (the bone edges move apart and out of proper alignment), simply avoiding the activity that caused the injury may just be sufficient. Otherwise, you should avoid weight-bearing on that foot by using crutches, or even putting it in a cast. The rule of thumb is “if there is pain, don’t do it!”
Self-Care at Home
You can take these measures at home to speed up the recovery:
- Rest. Avoid activities that cause pain, swelling or discomfort — but don’t give up exercising altogether! During the recovery, try low-impact, nonweight-bearing endeavors like stationary bicycling, swimming, or pool running. These will let you maintain a level of cardiovascular fitness. Don’t resume your former training routine until the fracture is completely healed, otherwise it will only prolong the pain. If the pain has you limping, consider using crutches until you can walk normally without pain.
- Elevate your injured toe as much as you can. Lift your foot above the level of your heart. Prop your foot up on a table or chair when you sit, and on a stack of pillows when you lie down. Rest your toe and do not exercise with that foot until the toe heals. Sometimes rest is all you need to treat a stress fracture.
- Do calf and anterior (front of) leg stretching and strengthening exercises twice a day.
- Apply an ice pack or cold pack to the swollen area. You can use a bag of frozen peas or corn for this. Be sure to put a thin cloth between the pack and your skin to avoid nerve damage and frostbite. Ice for 15-20 minutes at a time, at least three to four times daily or as often as hourly while letting your foot warm up to normal temperature between icing, until pain and swelling start to subside.
- Avoid walking barefoot. Wear proper shoes, one that is suited for your foot type, stride, and particular sports. Your doctor should be able to make recommendations.
- Consider taking acetaminophen (such as Tylenol) to relieve pain if necessary, but not ibuprofen (Advil, Motrin) and naproxen (Aleve) because some research suggests they can interfere with bone healing.
Rest is the key to the initial treatment of a stress fracture. The doctor may prescribe a walking boot or brace along with a cast or crutches for 6-8 weeks to help rest the injured area and limit the amount of weight-bearing.
Your rehabilitation may also include physical therapy to increase muscle strength and flexibility, which will also help prevent future injury.
Typically, after 4-6 weeks you can resume physical activities gradually, as long as they do not cause pain.
Most stress fractures heal with time and rest. Occasionally, though, some fractures refuse to heal or displace. Such cases may require surgery. The procedure may involve pinning the fracture site, and rehabilitation can take up to a half year.
How to Prevent a Stress Fracture?
The best treatment of a stress fracture is prevention. Just follow these advices:
- Make changes slowly. Start any new exercise program or impact sport slowly and progress gradually. A good rule is never increase the intensity, time, or distance by more than 10% each week.
- Get proper nutrition. Eat healthy. Include foods that are rich in calcium, vitamin D, and other nutrients in your diet, especially if you are a female athlete.
- Use proper footwear. Make sure your shoes fit well and are appropriate for your activity.
- Build muscle strength in the legs with strengthening exercise to prevent them from tiring too quickly and enable them to absorb greater strain for longer time. Replace shoes when needed (usually every 300-400 miles for runners). If you have flat feet, ask your doctor about arch supports for your shoes.
- If pain or swelling begins, stop the activity immediately and rest for a few days. If pain persists, see a physician.