The fatigue fracture (fatigue fracture) is caused by overloading a bone and develops gradually. Symptoms are insidious and are often not perceived as signs of a break. A stress fracture takes several weeks or months to heal completely.
What is a fatigue fracture?
A fatigue fracture is a fracture caused by stress over a long period of time. In contrast to acute fractures, in which too high a force acts on the bone once and causes it to break, in the case of a fatigue fracture the bone is repeatedly and permanently exposed to stress.
This leads to the fact that it becomes brittle over time and the smallest cracks appear in the structure. There are two types of fatigue fracture. The insufficiency fracture occurs when the bones have already been damaged by an illness. A stress fracture is the breakage of healthy bones that have only been broken due to permanent overload.
The fatigue fracture occurs very often in athletes, for example in running, but also in certain professions in which repetitive powerful movements are required, the fatigue fracture occurs. Usually one or more metatarsals, a neck or thoracic vertebra, or the ribs are affected. (see also: sports injuries)
The fatigue fracture is caused by constant overloading of a bone. The force is not strong enough to break the bone immediately. But the recurring stress causes the bone tissue to change.
So-called microfractures occur, which are the smallest gaps and cracks in the bone mass. Since the body always tries to counteract any disturbances that occur, it forms more bone substance, which is then broken down again. Due to the constant build-up and breakdown, the bone becomes more porous and eventually breaks. Overstressing the bone is favored by incorrect positioning of the feet, by insufficient muscle mass or by too thin bones.
The fatigue fracture on the foot usually occurs during running (Jones fracture or march fracture). Vertebrae and ribs can develop in severe coughing fits that occur over a long period of time (cough fracture). The fatigue fracture in the thoracic or cervical vertebrae is also known as Schipper’s disease, as it is caused by repetitive shovel movements.
Symptoms, ailments & signs
The fatigue fracture is caused by excessive strain, mostly through hard physical work or during sport. It is often a cracked area, less often a smooth breakthrough. This is why the symptoms of a fatigue fracture often differ from those of the classic fracture, which is usually triggered by an event such as a fall or a blow.
The patient usually does not recognize the fatigue fracture as such. It manifests itself in moderate to severe pain. The affected region can no longer be properly loaded and loses functionality. However, if stress does take place, it is associated with severe pain. The fatigue fracture usually occurs in the foot or in the hand. In these areas, comparatively small bones are exposed to very high loads.
The area affected by the fatigue fracture not only hurts very much, but also swells clearly. The surrounding tissue is supplied with more blood and therefore often feels warm or even hot. In rare cases, the fatigue fracture is also accompanied by a hematoma. This hematoma arises inside, but comes to the surface of the skin after a few days.
The clearest indication in addition to the pain is a partial to almost complete immobility and poor performance of the affected part of the body. A displacement of the bones, as in a classic fracture, is observed less often.
Diagnosis & course
A fatigue fracture is initially noticeable as a slight pain. The pain increases with sustained exertion, but decreases again when the patient is at rest. There is often swelling and reddening of the skin at the break point. Often the complaints are not perceived as a break, as they develop insidiously.
In contrast to an acute fracture, the bone remains functional for a long time after a fatigue fracture. Only after a long period of time does it become impossible for those affected to stress the bones. At this point in time, the pain does not subside, but can be felt over the long term.
The diagnosis is made using imaging techniques such as x-rays, magnetic resonance imaging (MRI), scintigraphy, or computed tomography (CT). The doctor can see the fine cracks in the bone tissue and the break himself. However, the diagnosis is usually made quite late, as the symptoms are often not correctly interpreted and the doctor is only consulted after a long period of suffering.
When should you go to the doctor?
If worsening pain is noted that is not attributable to any other cause, a doctor should be consulted. A stress fracture definitely requires medical evaluation and treatment. That is why it is best to see a general practitioner at the first sign. Expert advice is required at the latest when swelling and reddening of the skin appear. Other warning signs: pain at rest and restricted mobility of the affected limb. Anyone who experiences these symptoms should see a doctor.
A fatigue fracture results from constant stress on the bones. People who play a lot of sport or do physically strenuous work should therefore have regular check-ups carried out and speak to their family doctor if the warning signs are mentioned. Other contact persons are the orthopedic surgeon or the chiropractor, depending on the position and severity of the break. If you have acute complaints, you should go to the nearest hospital. After the initial treatment, physiotherapy measures are indicated. On the one hand, to promote recovery and, on the other hand, to avoid renewed fatigue fractures.
Treatment & Therapy
The treatment of a fatigue fracture is based on how far the damage to the bone has progressed and where the fracture is located. If an impending fatigue fracture is recognized early on, it is often sufficient to avoid the stress that is causing it and to protect the part of the body.
This allows the bone to recover and the bone tissue to regenerate. Furthermore, physiotherapeutic measures can support healing. If the fatigue fracture has already occurred, the bone is immobilized with a plaster cast and pain-relieving medication is administered. If the fatigue fracture has not been recognized for a long time and the bone is very damaged, an operation may be necessary. There are various operative procedures for this.
The bone can be strengthened with a nail inserted into the bone marrow. The screw connection with metal plates from the outside is also used in the event of a fatigue fracture. Finally, there is the cancellous plastic. Here, bone material is removed from the pelvis and inserted into the fracture site. Depending on the type of treatment, the bone can be carefully and very lightly loaded again after two to four weeks. In severe cases of a fatigue fracture, however, it can take up to six months before the bone is ready for use again.
A fatigue fracture can be prevented by not permanently overloading the body. When exercising you should on the one hand pay attention to the correct posture and on the other hand take seriously any signals from the body that indicate overload. In running sports, shock-absorbing shoes are used for prevention. In the case of existing underlying diseases, such as osteoporosis, the stress on the musculoskeletal system should always be kept low as a prevention against a fatigue fracture.
A fatigue fracture requires a lot of aftercare and rehabilitation work. The fatigue fractures formerly known as “marching fractures” were formerly a frequently observed phenomenon among marching soldiers. Today, bones are more likely to tire in people who are physically active, but mostly without an external cause that would justify a broken bone.
After the acute treatment of the fatigue fracture, there is a relief phase. In this the demineralized bone of the patient is treated by physiotherapy. Physiotherapy gives the bones impulses so that they can maintain their bone synthesis performance. The person concerned can only load the bone after a fatigue fracture if there is sufficient stability in the bone structure.
If pain occurs during exercise, the bone must be relieved and strengthened again. One of the most important points of follow-up care is that the training load is kept lower than before. The training units have to be adjusted so that a new fatigue fracture cannot occur. The aftercare phase can sometimes take a long time.
If there is no training overload, an analysis of the causes of the fatigue fracture must be carried out during the follow-up. Using gait analyzes or equipment training, overload zones can be identified and compensated for. Special shoes or orthopedic insoles come into question. A change in certain movement sequences can also provide additional relief. In addition, the intake of calcium, vitamin D supplements or bisphosphonates additionally strengthen the bones.
You can do that yourself
Since the fatigue fracture is usually caused by excessive stress, patients can also do a few things in everyday life as part of self-help in order to achieve an uncomplicated and quick healing of the fracture and to prevent it from reoccurring.
In the acute phase, the main concern here is to strictly follow the doctor’s rules of conduct and to consistently protect the affected area. In the foot area, for example, this can be the use of walking aids. Any pain or swelling can also be treated well by yourself by elevating the corresponding part of the body, by cooling or using pain relieving trauma ointments.
The patient’s help is also required in the regeneration phase following the acute state of fatigue failure. Reloading, for example an affected foot, is best increased gradually to avoid another break. It is also important to strengthen the muscles in the affected region, as muscles wrap around the musculoskeletal system like a protective corset.
In the foot area, movements that strengthen the small muscles of the foot and also increase mobility in this area are useful. All these measures, which are best discussed in advance with the attending physician, serve to fully restore functionality and to minimize the risk of renewed injury.