What is a stress fracture?
A stress fracture is a small, superficial crack in a bone. It is a form of overuse injury from repetitive stresses on the bone.
The weight-bearing bones of the lower leg and foot are the most common places to sustain a stress fracture. In fact, more than half of all stress fractures affect the lower leg and foot. These bones and the muscles that support them constantly bear your body weight and absorb the forces of walking, running, jumping, and other activities. When the supporting muscles fatigue, they transfer the force to the bones. This adds stress and can cause a crack to develop.
Stress fractures and other overuse injuries are common in people who play sports and participate in other physical activities. Stress fractures are one of the most common sports injuries. However, people who perform repetitive activities for work are also at risk for these injuries.
If you are at risk for this type of injury, be alert for signs of a stress fracture. A red flag is pain that occurs with activity and subsides with rest. It is important to seek prompt medical care if you experience this type of pain.
You will need imaging exams to confirm the diagnosis and gauge the extent of the injury. Continuing to be active and put stress on the bone can result in a complete fracture or broken bone.
What are the different types of stress fractures?
Stress fractures most often occur in the foot and lower leg, including these bones:
Metatarsal, the long bones of the foot. Stress fractures in the foot most commonly occur between the second and third metatarsals, which are thinner than other foot bones and absorb the most impact when running or jumping.
Calcaneus, the bone in the heel of the foot
Fibula, the smaller bone in the lower leg
Navicular, a bone on top of the middle part of the foot
Talus, a bone in the ankle joint
Tibia, the front bone of the lower leg, commonly known as the shin bone. This is the most common site of stress fractures. Symptoms of a tibial stress fracture are similar to those of shin splints, which describes inflammation of the muscles and tendons around the shin bone.
Less commonly, stress fractures can occur in the lower back.
What are symptoms of a stress fracture?
The symptoms of a stress fracture are similar to other types of overuse injuries. Pain is the most common symptom of a stress fracture and typically starts gradually.
For a lower leg or foot stress fracture, pain occurs with weight-bearing activities and can worsen over time. Resting or stopping the aggravating activity will ease the pain. Other stress fracture symptoms include swelling and tenderness in the area.
Do not delay if you suspect you may have a stress fracture. Seeking medical care early after symptoms begin generally results in a better outcome. The sooner you get an accurate diagnosis and allow the bone to heal, the sooner you will be back to an active lifestyle.
How are shin stress fractures different from shin splints?
Shin splints is a term that describes inflammation of the muscles, tendons, and bone tissue around the shin bone, medically known as the tibia. A stress fracture is when a small crack or series of cracks happens in the shin bone itself.
The symptoms of shin splints and shin stress fractures are similar: pain in the shin area that typically goes away when activity is stopped. However, with a stress fracture, the pain is often described as being a deeper, throbbing pain compared to the duller ache of shin splints.
Treatment for both shin stress fractures and shin splints involves resting the affected area and refraining from any physical activities that put pressure on the lower leg, allowing the injury or inflammation to heal.
What causes a stress fracture?
Stress fractures are the result of pressure from impact on the bones of the lower leg and foot. If the bones are weak, either due to an underlying condition or from muscle weakness that transfers stress to the bones, a small crack or series of cracks can occur.
Stress fractures tend to happen after a sudden increase in your activity level. This could be more frequent activity, longer duration of activity, or higher intensity of activity. Any of these increases can contribute to the muscle fatigue that makes bones more vulnerable to a stress fracture.
What are the risk factors for a stress fracture?
There are a number of factors that can contribute to a stress fracture. Some of these factors are extrinsic, meaning they are outside the body and not related to personal health factors. Intrinsic factors are ones you may not be able to control, such as your age, foot structure, and some underlying conditions, like osteoporosis.
Extrinsic risk factors for stress fracture
Changes in surface, which alters the forces on your bones. Examples include moving from turf to grass or a treadmill to pavement.
Poor conditioning, or doing too much too soon. This can include people starting an exercise or activity for the first time. It can also include athletes beginning a season too vigorously without giving their bodies time to adjust. Adequate periods of rest are important to allow the body to heal and adapt.
Poor technique, which often results from something that interferes with proper foot or leg mechanics. Compensating for another injury, such as tendinitis, can change the way your foot absorbs stress. This change increases the risk of a stress fracture.
Worn out or improper equipment, which can’t support the bones and muscles the way they should. Shoes that no longer have adequate cushioning can no longer protect the bones and muscles from stress. Improperly fitting shoes can also change the mechanics of the foot or leg.
Intrinsic risk factors for stress fracture
- Age, which is a contributing factor to osteoporosis and other conditions that weaken bones and muscles
- Foot conditions, such as blisters, bunions, plantar fasciitis, and tendinitis, which can change the way your foot hits the ground
- Muscle weakness, particularly lack of core strength, which can cause issues with balance and flexibility
- Osteoporosis, a condition marked by thinning and weakening of bones. This makes them unable to withstand even normal stresses. Stress fractures can occur with daily activities.
- Sex, as women may be at higher risk for osteoporosis and other bone changes due to estrogen levels
- Weight, which can be a factor at both the low and high end. Excess weight can put added pressure on muscles and bones, wearing them down faster. Someone who is underweight may lack muscle and bone strength, making them more susceptible to stress fractures.
Reducing your risk of stress fractures
You may be able to lower your risk of developing a stress fracture by:
Balancing cardiovascular, strength and flexibility exercises
Cross-training with a variety of sports and activities
Maintaining a healthy weight
Scheduling periods of rest and time off from physical activities
Slowly increasing activities to allow your body to adapt
Taking time to warm up and cool down after physical activity
Treating any underlying medical conditions that may affect bone and muscle strength
Using the right equipment with the proper fit
If you could be at risk of a stress fracture, talk with your doctor about your activities. Ask about strategies specific to you and your activity that can help you avoid a stress fracture and other overuse injuries.
How do doctors diagnose a stress fracture?
Doctors can often diagnose stress fractures by evaluating your medical history and performing a physical examination. Your healthcare provider will likely ask you several questions related to your symptoms, including:
How long have you been experiencing pain?
How would you describe the pain? Is it a dull ache or a sharp, throbbing pain?
Does anything make the pain better or worse?
What type of work do you do?
What types of physical activities or sports do you play?
Do you have any diagnosed medical conditions?
What medication(s) are you currently taking?
Have you recently experienced an injury to this area of your body?
If necessary, your doctor will use imaging exams to diagnose a stress fracture, most commonly:
X-rays, though it can be difficult to detect a stress fracture on an X-ray due to its small size.
MRI (magnetic resonance imaging), which provides more detailed images of the affected area
Bone scan, which uses a radioactive tracer injected into the bloodstream to highlight the area of bone that was injured
What are the treatments for a stress fracture?
The goal of stress fracture treatment is to heal the bone. This starts with stopping the aggravating activity and resting. It can take time, up to eight weeks, for the bone to heal properly. To aid recovery, your doctor may recommend RICE (rest, ice compression and elevation). This will help relieve symptoms as well. Your doctor may also ask you to use a special shoe insert, walking boot, or crutches to keep weight off the bone. Your doctor may allow no-impact activities, such as swimming or cycling, during this time. In some cases, a cast may be necessary, which would eliminate even these activities. If the bone fails to heal, surgery may be the next step.
What are the potential complications of a stress fracture?
Stress fractures usually heal with adequate rest and treatment. However, complications can occur if you continue to push through the pain or do not allow enough time to heal before returning to activities. This includes nonunion (incomplete) healing and malunion (abnormal) healing. These can result in chronic pain and disability. You could also end up with a complete fracture or repetitive fractures.
When stress fractures continue to occur, osteoporosis may be the cause. Your doctor will likely evaluate your bone density and prescribe treatment if necessary. The best way to avoid the other complications of a stress fracture is to closely follow your treatment and recovery plan.