The pelvis is a ring-like structure of bones. The two sides of the pelvis are in fact three bones (ilium, ischium, and pubis) that grow together as people age. Strong connective tissues (ligaments) join the pelvis to the sacrum at the base of the spine. This creates a bowl-like cavity below the rib cage. On each side, there is a hollow cup (acetabulum) that serves as the socket for the hip joint. Many digestive and reproductive organs are located within the pelvic ring. Large nerves and blood vessels that go to the legs pass through it. The pelvis serves as an attachment point for muscles that reach down into the legs and up into the trunk of the body. With all of these vital structures running through the pelvis, a pelvic fracture can be associated with substantial bleeding, nerve injury, and internal organ damage.
There are three groups of patients susceptible to pelvic fracture. Teenagers, particularly those involved in sport, may sustain a pelvic fracture in which a small piece of bone from the ischium where the hamstring muscles attach is torn away by these muscles. This usually occurs with sudden muscle contractions. Many “pulled muscles” may actually be undetected avulsion fractures of the pelvis. This type of fracture does not make the pelvis unstable or injure internal organs.
Elderly patients with osteoporosis are at risk of fracture following a fall, even from a standing position. These injuries usually do not damage the structural integrity of the pelvic ring, but may fracture an individual bone.
Most pelvic fractures, however, involve high-energy forces, such as those generated in a motor vehicle accident, crush accident or fall. Depending on the direction and degree of the force, these injuries can be life-threatening and require surgical treatment.
A fractured pelvis is painful, often swollen and bruised. The patient may keep the hip or knee bent in a certain position to avoid aggravating the pain. If the fracture is due to a high-energy injury, there may also be serious injuries to other parts of the body. There is usually considerable bleeding, which can lead to shock. These patients need to be taken to a trauma centre as soon as possible for definitive care.
All pelvic fractures require a number of X-rays from various angles, to show how displaced the bones may be. A computed tomography (CT) scan may be ordered to define the extent of the pelvic injury and other associated injuries.
Nonsurgical Treatment: Stable fractures, such as the avulsion fracture seen in young athletes, will normally heal without surgery. Crutches or a walker will be needed for up to three months as full weight bearing will not be allowed until the bones are healed. Medications may be prescribed to control pain and to thin the blood to reduce the risk of blood clots in the legs .
Surgical Treatment: Pelvic fractures that result from high-energy trauma are often life-threatening injuries because of the extensive bleeding. In these cases, the emergency management is the use of an external fixator to stabilize the pelvic area. This device has long screws that are inserted into the bones on each side of the pelvis and connected to a frame outside the body. The external fixator allows surgeons to address the internal injuries to organs, blood vessels and nerves.
Longer term management depends on the type of fracture and the patient’s condition. Each case must be assessed individually. Some pelvic fractures may require traction. In other cases, an external fixator may be sufficient. Unstable fractures may require surgical insertion of plates or screws.
Stable pelvic fractures heal well.
Pelvic fractures sustained during a high-energy incident may have significant complications, usually due to the associated injuries to blood vessels and internal organs. If these injuries are addressed, the fracture usually heals well. People may walk with a limp for several months because of damage to the muscles around the pelvis. These muscles take a long time to become strong again. Subsequent problems, such as pain, impaired mobility, and sexual dysfunction, are usually the result of damage to nerves and organs associated with the pelvic fracture.