The common image of a bone fracture is of a single traumatic event that causes the injury. However, this is not always the case. Stress fractures can occur over time from small amounts of stress placed on the bone. Repetitive impact activity, such as running, can cause stress to a specific bone, resulting in chronic pain.
A stress fracture occurs when the body is unable to make new bone tissue as quickly as microtraumatic events break the bone down. Eventually a crack occurs in the bone.
Pain at a specific location during and after sports is typically the first sign of a stress fracture. As the pain progresses, athletes will not enjoy participating in sports or workouts, and their performance will be limited. Pain subsides with rest; however, it quickly returns upon resumption of sport activity. The pain is typically achy and can be difficult to pinpoint. Swelling may also occur.
Bones in the legs and feet are most susceptible to stress fractures. They support the body's weight and absorb a great deal of shock from running, jumping and landing. The bones of the lower leg (tibia) and the foot (metatarsals) are areas of particular concern. The hip, thigh (femur), pelvis and lumbar spine (spondylolysis) are also potential trouble areas.
Stress fractures are diagnosed by a physician after a clinical exam and radiographic imaging. Sometimes a stress fracture is not identified on an X-ray until the healing process has begun. New bone surrounds the fracture site in an attempt to heal the injury, and this can be viewed on an X-ray four weeks after the fracture. Other imaging techniques, such as MRI or bone scan, can locate the injury before it is visible on an X-ray.
The main treatment prescribed is usually rest; however, the location of the stress fracture may mandate a specific treatment plan. In order to relieve an athlete's pain, a physician may recommend using crutches, immobilizing the area with a cast or brace—or even surgery. During the healing process, athletes may be cleared to perform low-impact cross-training, such as pool workouts or biking, if pain free. Icing the injury may reduce the pain. For individuals whose underlying bone health is of concern, further testing of bone density can be done.
It's essential for athletes to consume sufficient calories and recommended amounts of calcium and vitamin D to promote bone health. A return to sports is not allowed until an athlete is pain-free when performing sport-specific exercises. Depending on the location of the stress fracture, athletes are usually held out for four to eight weeks.
Older teenagers, Caucasians, Asians, athletes in poor condition and female athletes are at higher risk for stress fractures. Other factors that contribute to developing a stress fracture include sport of choice, training regimen, surface (e.g., grass or concrete) and footwear. Athletes involved in running sports (e.g., track, cross country, soccer and basketball) are at higher risk due to the weight bearing forces. Abrupt changes in participation also increase the risk. An injury may occur if a deconditioned athlete has a sudden increase in length of practice time, frequency, or intensity. Running on hard surfaces like concrete, in shoes with poor shock absorption (e.g., cleats or shoes older than six months) may also increase an athlete's risk of a stress fracture.
Strategies to Remain in the Game: Prevention
- Begin any new activity slowly and increase the volume, frequency and intensity gradually (no more than a 10 percent per week in any category)
- Wear properly fitting, shock-absorbing shoes, and replace them every 300 to 500 miles
- Run on softer surfaces like a cushioned track, a running trail or grass
- Take calcium and vitamin D in amounts appropriate for your age and gender
- Mix in low-impact activities such as biking and swimming
When in Doubt: Get Checked Out
The following symptoms should warrant evaluation by a physician for stress fracture:
- Pain or swelling in the same area persisting for more than a week
- Pain reoccurring despite rest from sport
- Pain that becomes progressively worse with less stressful activity (e.g., walking)
- Persistent pain and history of previous stress fractures
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