In this article, we are going to cover:
- The anatomy of the pelvis
- Types of pelvic fractures
- Pelvic fracture concerns
- How to manage pelvic fractures
Anatomy of the Pelvis
The pelvis is made from two bones. The bones join in the front, at the symphysis pubis, and in the back with the sacrum, at the sacroiliac joints. This forms a ring, and typically when a ring breaks it will break in two places. The pelvis contains ligaments that help hold the sacrum to the iliac bones, the two pubic bones at the pubic symphysis, and the sacrum to the coccyx. There are also blood vessels and nerves that run through the pelvis so if there is significant trauma these can be damaged.
Types of Pelvic Fractures
Pelvic fractures are categorized into 3 different types that go from most stable to least stable.
- Type A includes avulsion fractures, iliac wing fractures, and transverse fractures through the sacrum. These are stable and do not fracture through the pelvic ring.
- Type B includes open book and lateral compression fractures. These are rotationally unstable but are vertically stable.
- Type C fractures are vertically and rotationally unstable.
Pelvic fractures can occur from several different types of injuries. They are described as low energy and high energy events.
- Low energy events:
- Ground level falls
- Avulsion fractures from sports
- These types of fractures tend to be stable and occur typically in adolescent and elderly populations
- During an assessment of the pelvis, the patient may feel stable and we may not feel any crepitus but it may be painful.
- High energy events:
- Motor vehicle crashes
- Pedestrian vs auto crashes
- Falls from significant heights
- These fractures tend to be less stable and you may feel crepitus and instability when you are assessing the pelvis.
Management and Pelvic Fracture Concerns
Once we think our patient has a pelvic fracture what do we do?
The first thing we want to do is try to stabilize it to keep it from moving more and increasing the risk that the vasculature or nerves running through the pelvis get damaged. We also want to try to keep the pelvis stable and try to minimize the amount of blood lost through bleeding from the bones in the pelvic fracture. Patients can lose around 1-2 liters of blood with a pelvic fracture, so it is important to try to stabilize the fracture to decrease blood loss and minimize further injury.
How do we stabilize the pelvis?
One simple solution is to tie a sheet around the pelvis to hold it together. In the past, things like pneumatic anti-shock garments, or MAST pants were used, but most places do not carry these anymore. Once you stabilize the pelvis, by using a sheet, blanket, or pelvic splint, you should prepare to treat the patient for hypovolemic shock. This is important since we cannot see the blood loss from pelvic fractures. It can be hard to estimate how much blood the patient is losing so you must monitor the patient’s vitals frequently. Hypovolemic shock is more common in unstable pelvic fractures than in stable fractures.
How do we minimize pain?
Pelvic fractures can be quite painful and ambulances are not always the smoothest ride. It is likely that your patient will be quite uncomfortable during transport as you hit every tiny bump in the road. It is important to try to be smooth and gentle when loading and unloading your patient from the ambulance as you do not want to jar the pelvis.
In summary, pelvic fractures can be dangerous and difficult to diagnose because they are internal. Thoroughly assess your patients on scene, especially elderly patients, and consider the mechanism of injury. Just because you cannot see it does not mean it is not there. Be sure to assess the pelvis on an elderly fall patient, even if you are just called for a lift assist. If the patient has pain while standing and walking, and this is unusual for them, bring them in to have imaging done, even if the pelvis felt stable, just to be safe. The patient could have a stable pelvic fracture that we cannot see.
In addition, just because a patient is young, does not mean that they cannot have a stable pelvic fracture. Adolescents are at risk of avulsion fractures to their pelvis from sports. If the pelvis is unstable wrap it to stabilize it and minimize bleeding, and always frequently assess vitals so that you can recognize early hypovolemic shock.