If you put too much stress on your foot while jogging, its skeleton and ligamentous apparatus can literally come under "stress". At a certain point, the bones can no longer withstand the load and a fracture occurs (technical term = fracture).
1.1 What is a stress fracture anyway?
A stress fracture is a partial or complete fracture that occurs due to repeated so-called "microtrauma". Microtrauma often involves microscopic injuries in the musculature or bone tissue. In a stress fracture in the foot, the so-called os metatarsale II is particularly often affected. It is the longest of the metatarsal bones. Stress fractures can also occur in other parts of the foot in runners.
1.2 How does the stress fracture occur?
The stress fracture is a typical injury caused by overload. Anyone who trains the same exercises too intensively or too frequently, or exposes their bone apparatus to too intense a load, stresses it. As a result, small injuries to the bone occur again and again. These initially go unnoticed and those affected do not limit their training intensity.
In fact, the body first responds by the bone "repairing" itself over and over again and even becoming stronger. In the process, the so-called "osteoblasts" are activated. These bone cells are responsible for building up bone substance. But as soon as you do not regenerate sufficiently or the load is regularly too high, the bone is damaged bit by bit until finally the stress fracture occurs. It comes seemingly suddenly for many athletes, but it is the result of a usually longer process.
In the first phase, the bone is also not really fractured yet. Rather, the bone density has decreased so much due to the load and the lack of regeneration that it leads to pain and ultimately a real fracture can occur.
So: a stress fracture in running is caused by the disproportion of load and regeneration.
By the way: If the bone apparatus is not loaded at all, the stimulating stimulus on the osteoblasts is missing, so that they form less bone substance and the degradation by the osteoclasts predominates. To maintain or improve bone density, regular training is important.
1.3 How can I recognize a stress fracture?
You can recognize a stress fracture by pain after jogging. The pain is described as bony pressure pain. You can often also recognize a local swelling on the foot.
However, because the stress fracture usually develops gradually, you may not feel anything for a long time, despite constant microfractures, until suddenly a sharp pain "shoots" through your foot while running.
1.4 How do I find out if I have a stress fracture?
A typical symptom of a stress fracture is bony pain, which occurs primarily under stress during running or jogging. However, only imaging by the doctor provides certainty. If the stress fracture is already far advanced, it can also be seen after an X-ray. On an X-ray, the stress fracture is usually only visible when it has already been developing for several weeks. A more detailed picture and especially at an earlier stage of the stress fracture is provided by an MRI. The MRI can be used to detect bone edema, for example. Your doctor can even use the MRI findings to make a prognosis as to when you can start playing sports again.
1.5 How do I treat the stress fracture as a runner?
If you are diagnosed with a stress fracture, the first thing to do is to immobilize it. This is especially true if the fracture is already in an advanced (=higher grade) stage. This is the case when a so-called "fracture line" is already visible and the bone has already broken through. If a "real" fracture of a metatarsal has occurred, regeneration and healing take considerably longer. This is especially true if the outer metatarsal bone was damaged at its base. Then several months of rest are required for the foot.
When immobilizing, cold can help relieve the pain and irritation. To relieve the foot when walking, insoles can make sense.
As part of a passive therapy (=only the symptoms are relieved or the body is supported in healing, but no causes are eliminated), the use of NSAIDs can help. Specifically, you can relieve pain with ibuprofen tablets or ointment. However, you should not do this permanently, but only to break the pain cycle.
Taking painkillers for a long time can distort your body feedback. For example, you may not realize that you are putting too much stress on your foot too soon with the stress fracture because of the pain medication. This can significantly prolong healing.
Manual therapy can be helpful. Often, a stress fracture is caused by a purely biomechanical problem. For example, hardened calf and shin muscles can mean that shocks are no longer adequately absorbed when rolling and you consequently land too hard on your foot. Manual therapy loosens these muscles and reduces the strain on the foot.
Good to know: On the Internet or elsewhere, one often reads that shock wave therapy can also help with a stress fracture. In fact, a positive effect of this form of therapy on a stress fracture has not yet been proven by a study.
What you can do as part of active therapy:
- You look for the factors that promoted the stress fracture and correct them. For example, it may make sense to adjust your training volume or your diet.
- If you repeatedly experience bone pain or stress fractures after jogging, an examination of your blood values in the laboratory can provide information. There you can see, for example, how hormones such as testosterone, parathyroid hormone or minerals such as calcium and phosphate are metabolized.
- Continue your training without stressing or overloading the affected areas. Swimming or cycling is a good alternative to jogging.
If the therapy after the diagnosis "stress fracture" does not bring any success or if there is always severe pain despite therapy, surgery may be the last alternative to be chosen. During surgery, a plate is inserted to support the affected bone, for example.
1.6 How can I prevent a stress fracture while running?
As you have now learned, stress fracture is always a result of too intense loading combined with lack of recovery.
- You can therefore act preventively by avoiding, for example, too rapid increases or sudden changes in training conditions (different surfaces, different footwear) during training.
- Strengthening your foot and lower leg (shin/calf) muscles will do you a lot of good. These muscles absorb shock while running and reduce the load on your feet.
- Do an equipment check and replace "worn-out" running shoes with new ones. Use insoles if, for example, a treadmill check reveals a foot malposition. Get advice from a specialist retailer when buying running shoes. And for motivation you can design your own running shirt