When it’s icy and slippery, trauma surgeons have their work cut out for them, because the number of bone fractures, especially to the forearm and neck of the femur, often increases rapidly then. But bone fractures are not only an issue in winter: In addition to these common fractures caused by falls, in which usually only one bone is affected, there can also be much more complicated bone fractures caused by traffic accidents, for example. But how does a bone fracture occur and how long does the healing process take? We answer these and other questions below.
Bone – a hard framework for the soft core
Our bony body framework makes up about 20 percent of our weight, anchors muscles and ligaments, and protects our internal organs in the head, chest and pelvic regions. Bones consist of almost 50 percent inorganic material such as calcium phosphate, 25 percent connective tissue structures and 25 percent water. They are very stable: a fully grown bone can withstand a pressure of up to 15 kilograms per square millimeter – so a femur can support a total of a good 1.5 tons.
How does a bone fracture occur?
Despite its enormous load-bearing capacity, when stronger forces are applied to the bony skeleton, a bone cannot escape due to its brittle, hard substance – a bone crack (fissure), a bone fracture (fracture) or even a splintering of the bone into several parts (multiple fractures, complicated fracture) occurs. If a fracture results in displacement of the fragments, it is called a dislocation. Common cause of a bone fracture is a sudden and strong force, for example, by a:
- Accident
- Fall
- Shock
- Blow
But repeated overloading can also cause a bone to break. One speaks then of a fatigue fracture or a stress fracture. In addition, there are so-called pathological fractures, in which a bone breaks without (or by little) external impact. In this case, the bone structure is altered in such a way that the bone cannot withstand any pressure load – for example, in the case of bone-altering metabolic diseases such as severe osteoporosis or brittle bone disease, bone cancer or a metastasis in the bone.
Different types of bone fractures
The way the bone breaks is pure physics. For example, depending on the force applied, the following types of fractures may occur:
- A smooth breakthrough
- A breakthrough with dislodged bone fragment on the opposite side
- A spirally twisted bone fracture (spiral fracture) or
- Many bone debris
In childhood, the bone is not yet so brittle and can give way better: There often occur the so-called greenwood fractures. In greenstick fractures, the bone breaks only on one side, or it is compressed or the delicate periosteum is injured, but the bone resists. A kink is formed, like a young green twig – hence the name. In addition, fractures may be associated with other injuries, such as injuries to the skin, nerves, joints, or adjacent organs. Fractures are classified according to a wide variety of criteria, such as their location, the number of fragments, or whether the fracture is open or closed.
How long does a bone take to heal?
As a guideline, after a bone fracture, it usually takes about six to twelve weeks for the bone to be able to bear a full load again. For children, three to four weeks of healing is possible, and for adults, it can take as many months. How long it actually takes for a fracture to heal depends on a variety of factors, such as:
- The type and extent of the fracture (a complicated comminuted fracture will heal more slowly than a smooth penetrating fracture).
- The age of the affected person (in children, bones grow together more quickly and bone misalignments can be corrected well; with increasing age, the healing time is prolonged)
- The localization of the fracture (certain bones heal faster than others).
- The type of healing (direct and indirect fracture healing).
- The type of treatment (which depends mainly on the type of fracture).
Localization: how long does which fracture take to heal?
Which bone is affected affects how long it takes to heal.The following rough guide values apply, although the influencing factors already mentioned must also be taken into account:
- A collarbone fracture heals in an adult, for example, after six to eight weeks (immobilization should last three to four weeks).
- A femur fracture, on the other hand, takes circa ten to 14 weeks, but healing can drag on for up to six months.
- A nasal bone fracture can be healed after only two weeks.
- A rib fracture heals in about twelve weeks, with simple fractures faster.
- A broken wrist takes about five to six weeks to heal.
Basically, it can also be said that a joint fracture or a fracture near a joint usually takes longer to heal.
Indirect and direct fracture healing
There are two different ways in which a fracture can heal. Indirect or secondary fracture healing involves the development of what is known as callus, or scar tissue, at the fracture ends of the bone, which bridges the fracture site and slowly transforms into bone. This development takes a long time, so that even after several months to years, corresponding tissue can still be seen on X-ray images. Nevertheless, the bone can be loaded normally again earlier. Direct or primary fracture healing occurs without such scar tissue and only takes place if the ends of the bone fit together exactly, which is usually only the case with surgical treatment. The bone is fully functional again after approximately three weeks.
Proper treatment crucial for healing
When treating a fracture, the individual parts of the bone are usually rejoined and fixed in this position so that they can grow together again. An adequate blood supply must also be ensured. Various methods are available for treating a fracture, which have an effect on the duration of healing or on how quickly affected areas can be loaded again. Early treatment contributes to rapid healing. You will learn details about treatment later in this article.
Rehabilitation favors healing process
Treatment also includes appropriate rehabilitation measures: To avoid consequential damage to the muscles and joints, one usually does not wait until healing is complete before putting weight on the bone again, but begins rehabilitation as soon as the fracture has been adequately treated and stabilized:
- Affected individuals should try to use their non-immobilized joints as normally as possible.
- Isometric exercises (a special form of strength training) can additionally help keep immobilized muscles fit.
- If the affected person, for example, due to other injuries, an illness or for other reasons must keep bed rest, the early mobilization is usually done by physiotherapy exercises in bed.
In any case, you should consult with your doctor and get an explanation of what movements and exercises are recommended in the case of your fracture.
