fracture

Fracture: description

Physicians understand a fracture as a bone fracture: the bone is split into two or more fragments, which may also be displaced (dislocated). This happens when direct or indirect force acts on the bone from the outside, as in an accident.

Humans have a total of 206 different bones. In some places, bones have “break points” such as on the upper arm, which is particularly prone to breakage.

Every bone consists of mineral, elastic and connective tissue components. Blood vessels also pass through the bone. In the periosteum nerve fibers also run. Depending on the age of the human, the composition of his bones varies:

Bones of children have predominantly elastic shares. They therefore usually break as a so-called green wood break, in which the periosteum is still intact.

Bones of adults have a balanced ratio of mineral, elastic and connective tissue parts.

at older people The bones lose their elastic and connective tissue parts and therefore break more easily. In addition, the bones decalcify increasingly in age by the altered hormonal balance, which makes them brittle and brittle. A 70-year-old therefore has a three times higher risk of a bone fracture than a 20-year-old.

fracture healing

Bone tissue heals without scar. The goal of bone fracture treatment is for the affected person to relieve the bone as early as possible. Rapid healing is achieved when the anatomical axis relationships of the bone are correct. In addition, the break should be quieted and an adequate blood supply created.

The bone fracture healing time varies according to the skeletal segment. For example, a conservative treatment of a collarbone fracture takes only about three to four weeks, while a femoral fracture heals after about ten to fourteen weeks.

In children, a bone fracture heals faster because they can still grow and axial deformity and shortening can still be corrected. A bone fracture in children can therefore usually be treated conservatively.

A bone fracture can heal in two different ways and is treated differently depending on the species. Physicians distinguish direct and indirect fracture healing:

Indirect fracture healing

Most often, the bone heals via indirect fracture healing. This means that the bone forms a so-called callus at the ends of the fracture.

Inflammation phase: In the rupture zone, a bruise develops, which is eventually replaced by connective tissue cells such as granulocytes, mast cells and monocytes. This inflammatory phase takes place in the first four weeks.

granulation: In the next phase, a soft callus of granulation tissue forms. The callus runs from the ends of the fracture towards the middle. Since the fracture ends are poorly supplied with blood, a bone necrosis (dead bone tissue) of a few millimeters. The bone is therefore first slightly shortened to obtain fragment contact. The dead bone tissue is degraded by so-called osteoclasts, which is why one sees a widened gap in the X-ray during the first two weeks of the granulation phase. This is necessary for the bone to heal. Osteoblasts replace the lost bone tissue with new bone tissue.

Phase of callus hardening: The connective tissue cells, which migrate into the area of ​​the rupture, differentiate into dormant cells in dormant conditions. These slowly mineralize, which takes about three to four months. The new tissue then becomes progressively stiffer. Special growth factors form a new substance in and around the outside of the fracture. The sufferer notices this because the pain decreases with time as the bone ends are moved.

Remodelingphase: The remodeling phase starts from the third month and can last up to one year. The still braided new bone tissue transforms into lamellar bone. In the X-ray, this is visible by the beginning of new bone formation around the fracture. The initially unstructured mesh-like bone is becoming increasingly dense, which is supported by the tense muscle. The initially spherical callus becomes flatter, so that after months or years the bone cortex is only slightly compressed.

Direct fracture healing

In direct fracture healing, the bone fracture heals without visible callus. This succeeds only in directly fitting bone fracture. Healing without callus can therefore only be achieved by surgical measures. In the so-called compression osteosynthesis, the fracture is mechanically immobilized. It allows the bone fractures to be adequately perfused. Thus, new cells can form on the fracture surface, simulate new bone tissue and crosslink the fracture. The radiograph therefore shows no callus. The previously visible fracture gap blurs and disappears completely at the end.

Disturbed fracture healing

A clearly prolonged fracture healing suggests a disturbed fracture healing. The X-ray shows a broadened fracture gap.

If there is no bony connection after four to six months at the two ends of the bone, doctors speak of a “false joint” (pseudarthrosis).

Fracture: symptoms

Typically, fractures include symptoms such as pain and restraint of the affected limb. Physicians distinguish safe and uncertain fracture signs.

Unsafe fracture characters:

• The movement can be carried out spontaneously.
• motion pain
• Loss of function of the joint
• swelling

Safe fracture signs:

• deformity
• wrong mobility
• Crunching on the move

It is important to always check the peripheral blood circulation, motor function and sensibility in case of a fracture in order not to overlook possibly injured nerves, blood vessels or tendons!

nonunion

The pseudarthrosis manifests itself by swelling, overheating and pain during exercise and exercise. Since in a pseudarthrosis the healing process ceases, a so-called seroma forms between the ends of the fracture, creating a functional joint.

Fracture: examinations and diagnosis

If you suspect a fracture, you should consult a doctor for orthopedics and traumatology. He will first ask you about the accident and your medical history. Possible questions are:

• How did the accident happen? Was there a direct or indirect trauma?
• Where do you suspect a break?
• How do you describe the pain?
• Were there any previous injuries or previous damage?
• Have you had any complaints before?

If the patient can describe the accident exactly, this often already suggests a bone fracture. Subsequently, the doctor will examine the patient. He inspects the affected area in search of deformity and swelling. In addition, he feels, whether it is pressure-sensitive, or the muscles are particularly tense. He also checks whether the movement can be carried out properly and whether a creaking or crunching sound is produced.

Next, the doctor will test the distant pulse and thus the blood flow. To test the motor skills, he asks you to actively move your fingers and toes. Furthermore, the sharp and dull sensibility is checked.

A subsequent X-ray examination in two levels can confirm the suspicion of a bone fracture. If the pelvis or spine is affected, computerized tomography (CT) is usually performed for a more accurate diagnosis. Even the so-called occult fracture, which was initially not visible in the X-ray, can thus be detected. The X-ray images can then be used to describe precisely how far the bone fragment has been dislocated. The breakage may have shifted laterally, shortened, extended, twisted or bent in its axis.

Open breaks

If the skin above the fracture is open, there is an open fracture. It should first be covered in a sterile location at the scene of the accident and then uncovered again under sterile conditions only during the operation. This prevents germs from getting into the wound.

Closed bone fracture

If the skin over the fracture remained intact, it is a closed fracture. Sometimes you can not tell anything about the break from the outside. In other cases, abrasions to extensive skin defects such as skin squeezing are visible.

Fracture: causes and risk factors

In the term fracture, most people think of a traumatic bone fracture: a sufficiently high degree of violence has broken the actually solid and elastic bone. However, a fracture can also be caused by a disease. Basically, there are three mechanisms of bone fracture formation:

• A direct fracture occurs when external violence affects the healthy bone.
• A pathological fracture or spontaneous fracture is usually the result of a pathologically altered bone such as tumor metastases, bone cysts and osteoporosis.
• A fracture can also be caused by prolonged mechanical stress (fatigue fracture or stress fracture), for example during long marches or marathons.

Fracture forms

Depending on the incoming force and the shape of the bone, different forms of bone fracture result. Fundamentally, the direct and indirect effects of violence are distinguished.

Of the bending fracture is caused by a direct or indirect impact on the bone. On the concave side of the bone occurs a tensile stress, which is why the bone tears there. On the convex side, on the other hand, the pressure is so great that a so-called bending wedge is blasted out. This happens, for example, in a direct impact on the tibia.

One Rotary or torsional fracture is caused by indirect violence, in that a twist causes tension in the bone. This break can occur, for example, when falling in a ski boot with a blocked safety binding.

The spiral fracture has a spiral break gap. It is caused by torsional loads. Frequently, an axial load or gravity also plays a role. Mostly a spiral rotary wedge is created.

Tensile forces acting on the bone via a ligament or tendon insertion may cause a avulsion fracture (Avulsion fracture) arise. The fracture line runs transversely to the tensile direction, as in the case of an olecranon fracture (fracture of the upper edge of the ulna).

A compression fracture or compression fracture usually arises in the body longitudinal axis by an indirect action of violence. This usually affects the loose honeycomb structure of cancellous bone, which is irreversibly compressed. Typical examples are the vertebral fracture and heel bone fracture.

In the comminuted fracture The bone splinters by a strong force into many fracture fragments. The bone fragments are typically displaced (dislocated). In addition, the surrounding soft tissues are massively injured. A classic example is a weft fracture or a fracture fracture after a motorcycle accident.

In the Luxationsfraktur it is a joint near the joint, whereby the joint is additionally dislocated. There are two mechanisms of development: either the dislocation is the cause of the fracture, or fracture and dislocation have arisen simultaneously. Dislocation fractures can occur, for example, in the ankle, the tibial bone head and the hip joint.

The incomplete fracture refers to fissures and bony contours that are not completely broken. One example is the childlike greenwood fracture, in which the periosteum is still intact.

A nonunion Usually arises when the fracture has not been sufficiently sedated and the fracture ends have been moved or pulled apart. A distinction is made between septic and aseptic nonunion. There are the following causes for a pseudarthrosis:

• Movement in the fracture gap overloads the bone with the result that connective tissue bursts and bone trabeculae break.
• Too large a distance between the fracture ends can prevent the fractured ends from touching and forming a bridge.
• If the soft tissues are damaged too much, they can reach into the fracture gap and lead to delayed healing.
• Smoking or non-cooperative behavior of the patient

Fracture: AO classification of fractures

The various fractures are classified by the AO, the Association for Osteosynthesis Issues. The AO classification is used to accurately describe fractures and thus enable standardized treatment.

The AO classification is most commonly used for bone fractures on the long bones, such as the upper arm, forearm, thigh and lower leg bones. But also hand and foot injuries, Kieferfrakturen as well as fractures of the pelvis and the spinal column can be classified according to her.

In order to be able to perform a precise treatment, the severity of the fracture must be assessed. Four factors are crucial for this:

• Has the stability of the bone been preserved?
• Are the bone fragments still supplied with blood?
• Is there additional cartilage damage?
• Was the capsule band apparatus injured?

Fracture: treatment

What treatment options are available for a fracture, see the post fracture: treatment.

Fracture: disease course and prognosis

The prognosis of a fracture depends on the type of injury as well as the treatment. In most cases, a fracture heals well and without consequences after adequate conservative treatment or surgery. It is difficult to estimate an accurate prognosis in open debris fractures and bone fractures involving vessels. An infected fracture can cause the limb to be amputated if sepsis (“blood poisoning”) has developed. In older people, a fracture often heals more slowly. Especially with a joint fracture and joint near fracture Often, prolonged disturbances occur.