What is a pelvic fracture?
Fractures of the pelvis are particularly serious injuries because they can lead to the death of the patient, because in most cases other body structures are also injured by the violence, especially the nervous system and internal organs.
As a rule, pelvic fractures are mainly caused by traffic accidents or, less commonly, by falls from a great height and by crushing.
About 3% of bone fractures of the human body affect the pelvis, in patients with polytrauma the proportion is 25%.
This injury is especially suffered by adolescents and adults up to 50 years of age. Older people are rarely affected; this is important information in order to assess the social and economic impact of this violation.
Mortality as a result of pelvic fracture is relatively high; the survivors can only partially find their way back to their old state of health, in 20-30% of cases a residual disability remains.
As a result of pelvic fracture, pain, bladder weakness, sexual disorders such as impotence or neurological deficits (paresthesia, tingling, loss of reflexes, etc.)
may occur The correct care of a patient with pelvic fracture involves teamwork, in which surgeon, radiologist, orthopedist, urologist, neurosurgeon and internist work closely together, because this injury usually affects different areas of the body.
A pelvic fracture can lead to death due to the following causes:
- blood loss (hemorrhagic shock);
- violations of the central nervous system;
- Blood poisoning (sepsis).
Men are more frequently affected by pelvic fractures than women because they are more likely to be exposed to violence.
How is the pool constructed?
The pelvis is an anatomical structure formed from three fused bones: ilium, ischii and pubis.
The ilium is furthest up, the iliac crest can be felt about 10 cm below the ribs.
The sitting bone is the deepest; at the back of the buttocks, the sit-bone hump can be seen as the only hard bone tissue; the pubic bone lies furthest forward and can be felt between the legs in front of the genital organs.
The pelvis occupies a key position because it connects the femur to the spine, it forms a joint with the sacrum.
The shape of these bones is reminiscent of a shell whose opening points upwards to the abdomen and forms an oval when viewed from above.
In the human body, it contains the genital organs, the gastrointestinal apparatus and the urinary tract, as well as important vascular and nerve structures.
The three bones meet in the lower area and together form a depression, the acetabulum, which is also referred to as the hip joint or pelvic socket; the acetabulum takes up the head of the femur, the femoral head, and both together form the hip joint (articulatio coxae).
The two hip bones are connected at the back by the sacrum and together form the sacral-iliac joint or sacroiliac articulatio; at the front there is a connection via the pubic joint (symphysis pubica).
The stability of the pelvic bones results from the less mobile and perfectly matching joints and is supported by the strong ligaments that connect them to the sacrum (sacrotuberal ligament) and to the lumbar vertebrae (iliolumbal ligament).
How does the pelvis break?
The most common injury mechanism is a car accident, which affects both the driver and the front passenger; the accident may cause dislocation or complete loss of hip joint and fracture of the edge of the acetabular (acetabular fracture).
A strong rear-end collision, a head-on collision or an extremely rough stop can cause a strong impact against the dashboard.
The impact against the knee causes a violent, indirect impact of the upper femur against the acetabular socket, which can lead to an acetabular fracture and dislocation of the hip.
In order for such injuries to occur, it must already be a serious accident, because the head of the femur sits firmly in the pelvic socket and the joint capsule surrounding the two bones is very strong and stable.
For the development of a fracture, the hip joint must be bent. If the hip is in adduction, i.e. is brought in, the impact causes only a posterior fracture of the acetabulum of the hip joint, if the hip is spread out (abduction), a dislocation or subluxation can also occur.
If the head of the femur is pressed against the acetabulum with enormous force by the accident, it can break through and cause internal injuries. In some cases, the bone fragment of the acetabulum may shift (displaced fracture) or there may be a debris fracture, i.e. the bone breaks into numerous fragments.
The dislocation of the hip (dislocation) can also occur a certain time after the trauma because there is insufficient bone support.
How can pelvic fractures be classified?
The pelvic bones are very large, so there are a variety of different ways of fracture; some fractures are stable and less serious, others are unstable and dangerous.
The pelvic bones form an outer ring, the pelvic ring; if the continuity of this ring is not interrupted by the fracture, the stability of the pelvis is preserved; these include lesions on the iliac crest, pubic bone, lower and upper, anterior iliac spine.
According to the scientific author “Tile”, the fractures, which are unstable only at the horizontal level, cause a displacement of the pubic bone to a certain side. The displacement occurs in the vertical or anterior-posterior direction and the sacroiliac and sacrospinal ligaments are pulled or torn.
More serious fractures are unstable at the sagittal and horizontal planes, one side of the pelvis is pushed further up than the other. The injuries may occur in connection with a fracture of the transverse process of the fifth lumbar vertebra (L5), which is torn off by the iliac ligament, or with a lesion of the sacrum and sacroiliac joint.
The most dangerous fractures are often associated with neurological injuries of the lumbar and sacral plexus, which can affect the nerve roots from L4 to S3, including:
- continuity of the acetabulum in the horizontal direction;
- unilateral fracture of the ilium;
At this height, the sciatic nerve, pubic nerve, posterior femoral nerve, etc. originate, which innervate the legs, genital organs and sphincter muscles, among other things.
What are the symptoms and signs of pelvic fractures?
The symptoms include: pain in the injured area and swelling due to the violence suffered; the swelling is associated with a bruise, which is not necessarily visible at low altitude.
Immediately after the fall or accident, the injured person can still move, walk or ride a bicycle for about a quarter of an hour, but then the pain becomes unbearable.
Symptoms may be localized in the groin, coccyx or hip area.
There are cases when patients fell 10 km from home, with difficulty were able to get back on the saddle and ride home by bike.
Depending on the injury, symptoms of a neurological nature may also occur, such as paresthesia, loss of strength and sensitivity, pain and tingling. In one out of five cases, an acetabular fracture leads to a lesion of the sciatic nerve, which can cause a lifting weakness of the foot (stepper gait) due to paralysis of the anterior tibial muscle.
In the case of organ injuries, e.g. to the intestine, bladder, genital organs or arterial and vein trunks, the patient will feel specific symptoms.
How is pelvic fracture diagnosed?
To assess a pelvic fracture, it is important to know the injury mechanism.
In a traffic accident, patients with polytrauma often have a broken pelvis, but a fall by bicycle or from a great height can also cause a pelvic fracture.
An X-ray examination can be used to determine whether the continuity of the bone is interrupted; only if microfractures are suspected, magnetic resonance imaging or CT scan is performed, because they have a better resolution and also indicate bone edema, bruising and abdominal injuries.
For a better assessment of any existing concomitant injuries, the doctor can schedule further examinations in the emergency room: ultrasound of the abdomen, X-ray contrast examination of the urethra (urethrography) and angiography.
In the case of abdominal trauma, a thorough clinical examination must be carried out because of the possible accident-related complications.
The focus is on:
- open wounds;
- Effusions of blood;
- injuries of soft tissues;
- rectal and vaginal disorders;
- Instability on the vertical or horizontal plane.
The X-ray examination is carried out in several planes: with beam path from front/rear and oblique images of 45° or 135°.
The following diseases and injuries should be excluded by the doctor:
- Hip fracture
- Hip dislocation
- Abdominal pain in the elderly
- Pelvic injuries
- Shock (bleeding)
- Rupture of the rectus femoris
- Lesion of the flexor muscles of the thigh
- Necrosis of the femoral head