Definition
A fatigue fracture (synonyms: fatigue fracture, stress fracture) is a bone fracture caused by excessive stress over a long period of time. Although the diagnosis is often a bit difficult to make, once it has been made, it is almost always possible to achieve complete healing of the fracture by consistently immobilizing the affected limb.
Introduction
A fatigue fracture is a fracture of the bone caused by long lasting or often recurring excessive loads. Thus, an acute fracture does not occur suddenly due to external force, but it takes some time until the fracture has actually formed completely. In the end, this can happen by an unnoticed event.
Such fractures can occur in both healthy and diseased bones and are therefore referred to as either stress fractures or insufficiency fractures. Depending on the location of the fatigue fracture, there are different names for this type of fracture.
- The most common is the march fracture (on the second, third or fourth metatarsal bone)
- The Jones fracture (fifth metatarsal)
- The cough fracture (ribs or vertebral body) and
- Schipper’s disease (cervical or thoracic vertebrae)
Causes of fatigue fracture
A fatigue fracture is caused by a permanent overloading of the affected bone. Every bone has a certain load limit, the exceeding of which is manifested by tiny fractures in the bone (microfractures). These are initially harmless and are not noticeable.
Long-term or recurrent overloading or incorrect loading can cause a great many of these tiny cracks to occur. As a rule, the body can compensate for these small fractures by producing more bone substance. At some point, however, this compensation mechanism is exhausted.
Consequently, the increased susceptibility of the affected bone eventually leads to a fracture, which typically does not result from an obvious trauma, but can be triggered by everyday movement. Due to this development of the disease, it is understandable that (competitive) athletes in particular often suffer from fatigue fractures and that these occur more frequently in the area of the lower extremities. Women who suffer from a disturbed menstrual cycle or who are in the menopause are particularly often affected.
If there is a lack of the hormone estrogen (and many also suffer from osteoporosis), the bones can break more easily. Some foot malpositions also favour the occurrence of a fatigue fracture. These include the hollow foot and an outward rotation of the feet when walking, which leads to increased strain on the calf and shin bone.
Fatigue fractures can also occur as a result of long, violent coughing (especially on the ribs or vertebrae). In addition, there are a number of risk factors that make a fatigue fracture of one of the extremities more likely to occur even in otherwise healthy people. These include, among others:
- Taking certain medications (for example cortisone)
- A strict, unbalanced diet
- A narrow shin bone or a small calf circumference with little muscle mass
- A sudden change in training (for example, if you change your running speed/distance or the weight to be lifted) and
- Running tracks that are either hard, uneven or longer than 32 km.
