Stress Fractures: Causes, Symptoms, and Treatment
If you have ever been injured, you know the pain, frustration, and the worry. An active lifestyle comes with its set of health benefits, but overdoing any activity or doing it wrong puts you at risk of an injury. While minor muscle strains, aches, or pulls are common, some injuries can hamper your active lifestyle and daily functioning. One of them happens to be a stress fracture.
What are stress fractures?
Fractures sound scary for various reasons. Whenever a bone breaks or cracks, that injury is called a fracture. Although bones are strong structures and can withstand a remarkable amount of pressure, they can break too. Most often, a bone breaks when it is subjected to a stronger force, like an accident or a sports injury.
The break can either run lengthwise or across the bone. Depending upon the force, the bone can split into two or more pieces.
Typically, they are a result of an overuse injury. They occur over time when repetitive forces result in microscopic damage to the bone. The repetitive force is not great enough to cause a fracture, as seen in a broken ankle caused by a fall.
Although stress fractures can occur at any location where there is overuse, it is often found in the lower extremities, which include legs and feet. More than 50% of all overuse injuries occur in the lower leg due to weight-bearing activities like running, jumping, playing tennis, and dancing. By weight-bearing, we mean any activity that you perform on one or both feet, which makes the bones and muscles work against gravity. Commonly affected bones are shin bone, small bones in the foot, the heel bone, and the hip bone.
What causes stress fractures?
Bones are living, growing tissues. They constantly remodel themselves in response to stress or load by removing old bone (resorption) and adding new bone (ossification). This is a natural process and is important for maintaining bone health. However, when resorption happens at a higher rate than it can be replaced, it can lead to decreased bone mass. This may put you at higher risk for fractures. Excessive or untimely loading during the resorption phase without sufficient recovery may lead to stress fractures.
Risk factors for stress fractures
Certain risk factors put you at a higher risk for developing stress fractures. They can be a combination of extrinsic and intrinsic factors, making it a multifactorial condition. The main risk factors include:
1. People like athletes and military recruits who engage in high-intensity, repetitive activities, and recreational runners running an average of more than 25 miles (40km) per week are at an increased risk of stress fractures. Additionally, those who participate in basketball, soccer, or dance over prolonged periods daily are at an increased risk.
2. The most common cause is the sudden increase in physical activity- such as increasing the duration, frequency or intensity. This is also applicable for non-athletes who suddenly shift from a sedentary to an active lifestyle without a gradual break-in duration.
3. Consuming a diet low on vitamin D and calcium can cause your bones to be fragile and prone to fractures. Health conditions such as osteoporosis or osteomalacia (causes bone pain and muscle weakness) that weaken the bone strength, increase the probability of stress fractures.
Other risk factors include:
1. Women who have eating disorders, irregular periods, or are in the menopausal age group are at high risk. Estrogen is an essential hormone for maintaining female bone health. Low estrogen levels during menopause may make any woman prone to stress fractures.
2. People using improper or poor equipment, such as worn-out shoes that have lost their shock-absorbing abilities.
3. A change in the exercising surface; for instance, a runner moving from treadmill to a concrete surface.
So, if you belong to any of these categories or follow any of these practices, you need to be more careful.
What are the symptoms of a stress fracture?
The signs of a stress fracture include:
- Pain, which hurts at a specific point, depending on the bone that is affected
- Pain, which is exacerbated with activity and relieved with rest
- Pain that occurs throughout the day even during normal activities
- Swelling and tenderness (pain on touching) at the site of fractures
- Severe pain while hopping or jumping on the affected leg
The pain develops gradually and worsens with weight-bearing activities. If not treated at an early stage or left untreated, the pain only worsens and can result in additional stress fractures.
How is a stress fracture diagnosed?
If you suspect having a stress fracture, the most important thing is to stop performing any activities that cause pain. See your doctor as soon as possible to prevent any further complications.
1. Your doctor will perform a physical examination and evaluate you for the risk factors based on your medical history, activities, or any medications.
2. A physical exam may not be enough; usually, imaging tests are needed to confirm a stress fracture. X-rays may not help in diagnosing a stress fracture, as it takes up to several weeks for any evidence of stress fracture to show up.
3. Generally, the doctor may recommend bone scans or Magnetic Resonance Imaging (MRI), as these diagnostic procedures are more accurate in detecting early signs of a stress fracture when compared to X-rays. MRI is preferred as it is better at diagnosing different types of bones and any soft tissue injuries.
Stress fracture treatment
The stress fracture recovery may vary depending on its location and severity. The treatment’s objective is to relieve any pain and allow the fracture to heal so that you can resume doing day-to-day activities with ease. A majority of the stress fractures are treated non-surgically. It takes roughly six to eight weeks for the stress fracture to heal. In the meantime, you can follow these treatment protocols:
- Take complete rest from any activity that causes pain, as the additional load can worsen the condition
- Reduce the swelling or pain by applying ice packs to the injured areas, or as suggested by your doctor
- Resume training gradually after approval and consultation with your doctor. You can engage in non-weight-bearing exercises, such as swimming and cycling, to maintain aerobic fitness.
- Wear protective footwear, such as stiff-soled shoe, a wooden-soled sandal, pneumatic braces, or crutches to limit the stress on your foot and leg, as advised by your doctor
Stress fracture prevention
Prevention is undoubtedly the best management approach. These simple yet effective steps can help prevent stress fractures.
1. Ensure gradual progression
When starting a new activity, take it slow and gradually increase the duration, intensity, and frequency. Follow the 10% rule, ie, raise the amount of exercise by not more than 10% each week.
2. Wear proper footwear
Make sure that the shoe fits well according to your feet type and is appropriate for the activity. Ensure that you replace the running shoes every 500km to 600km.
Add a variety of activities to your training schedule to avoid repetitively stressing one particular part of the body.
4. Do strength training
Incorporate strength training exercises. Use free weights, bodyweight, or resistance bands to prevent early muscle fatigue and bone density loss that comes with aging.
5. Consume a nutritious diet
Follow a diet that includes a high amount of vitamin D and calcium to maintain bone health. The daily recommended amount for vitamin D is 400IU-800IU, depending on your age. Incase of reduced sun exposure or high levels of physical activity in athletes, you can supplement your daily intake with 2000IU-4000IU of vitamin D. The upper limit for daily intake for adults is 4000IU. Consult your doctor or a sports nutritionist before starting these supplements, as an overdose of vitamin D and calcium can have adverse effects on the body.
6. Handle underlying conditions wisely
If you have a known history of osteoporosis or other bone conditions, it is recommended to discuss with a doctor about how to manage these conditions with a healthy lifestyle.
Often, stress fractures are preventable by being mindful of your training and avoiding habits that may put you at risk.
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