What is it?
A stress fracture is a crack in a bone that results from repetitive sub maximal physical loading. In our case, running.
What causes it?
As muscles become fatigued their ability to absorb impact forces diminishes. This causes a redistribution of impact forces resulting in increased stress at focal points in the bone. If stress is applied at this point repetitively a tiny crack opens up in the bone and this is what we call a stress fracture.
Predisposing factors – Extrinsic
- Excessive volume and/or intensity and/or frequency
- Excessive fatigue
- Inadequate recovery
- Faulty technique
- Worn out
- Inadequate nutrition
- Inadequate hydration
Predisposing factors – Intrinsic
- Leg length discrepancy
- Muscle imbalance
- Muscle weakness
- Lack of flexibility
- Sex, size and body composition
Where do they occur?
Stress fractures may occur in virtually any bone in the body, but the most common sites of stress fractures are the second and third metatarsals of the foot. Stress fractures are also common in the heel (calcaneus), the outer bone of the lower leg (fibula), and the navicular, a bone on the top of the midfoot.
What are the symptoms?
- Pain that develops gradually, increases during the run, and decreases with rest.
- A spot on the bone that is extremely tender to press.
- It hurts if you hop on that leg.
How is it diagnosed?
X rays are commonly used, although sometimes stress fractures can’t be seen on regular x-rays or will not show up for several weeks after the pain starts. Occasionally, a CT scan or MRI will be used.
How is it treated?
The treatment generally requires avoidance of the activity that’s caused the injury. The majority of stress fractures heal within six weeks of beginning relative rest.
If running is resumed too quickly, larger, harder-to-heal stress fractures can develop. Re-injury also could lead to chronic problems where the stress fracture might never heal properly.
In addition to rest, shoe inserts or braces may be used to help these injuries heal.
How is healing assessed?
Healing is assessed clinically by the absence of local tenderness and functionally by the ability to run without pain. Returning to running should be a gradual process to enable the bone to adapt to an increased load.
- Follow a periodised training programme. This will build your mileage gradually and avoid many of the causes of a stress fracture.
- Maintain a healthy diet. Calcium and Vitamin D rich foods should be included in your daily meals.
- Take note of your footwear. Do not run in old, worn out, or poorly fitted trainers.
- If pain or swelling occurs, immediately stop the activity and rest for a few days. If continued pain persists, seek out a health care professional.
- It is important to remember that if you recognize the symptoms early and treat them appropriately, you can avoid a longer lay off from running.
Take home message
If something feels like a bone pain, don’t try and be brave and push through it. Stop immediately, even if its mid run. Seek the advice of a health care professional that can asses the injury.