What type of treatment is available for pelvic fractures?
With a wide variety of pelvic fractures one finds a similarly wide spectrum of treatment ranging from symptomatic treatment only, through bed-rest, traction, slings, external fixation, and a variety of surgeries. Because the pelvis has a rich blood supply and is mostly made up of spongy (referred to as cancellous bone) bone which heals very well, it is rare for healing to be delayed or insufficient. Treatment is therefore directed at problems with instability and displacement.
For stable pelvic fractures such as minimally displaced avulsion fractures and the pubic ramus fractures common in the elderly, it is not necessary to reduce or immobilize the fracture. Healing takes place even if the patient moves around. Management is therefore directed at reducing the pain and maintaining mobility. Prolonged rest is avoided and a gentle exercise program to retain range of motion can be used.
Pain, swelling and bruising settles over a period of three to four weeks and the fracture(s) heal at approximately six weeks. In the case of avulsion fractures, union of the fracture should be confirmed before returning to sports activity on a graduated basis.
More major injuries such as iliac wing fractures, straddle injuries or lateral compression fractures are patterns which are potentially unstable. They may be treated initially with bed rest. After a few days the x-rays may be repeated and the patient can be mobilized if there is no shift in position of the fracture. It would be usual to avoid weight bearing on the affected side for six weeks. These fractures can heal where they are and do not have to be reduced back to the original shape.
A pelvic sling is used temporarily in cases where the fracture pattern is unstable or if there is severe bleeding. In straddle injury patterns squeezing the fracture together by using a pelvic sling may prevent further displacement and may put pressure on the bleeding points and lessen bleeding. This type of treatment is usually stopped early and a more definitive treatment plan used.
Many acetabular fractures were formerly treated with traction. Pins were placed in the femur and weights attached to pull the hip down out of the injured socket. In some cases the joint surface of the socket was restored to a better position. The advantage of this style of treatment is that surgery is avoided but the joint surface is usually still irregular after healing has occurred and the joint is very likely to be painful and arthritic.
Traction may be used in acetabular fractures where there is pre-existing arthritis of the hip or where the patient is elderly. In the latter case it may be considered safer to let the acetabular fracture heal and undertake a total hip replacement once that has happened. A hip replacement is a lesser operation than open reduction of an acetabular fracture and the results are predictably good in the elderly. Traction may also be used in unstable fractures of the pelvic ring to prevent shortening of the affected side. Usually this would be a temporary measure while a definitive treatment plan is formed.
Management of Bleeding from a Pelvic Fracture
After fractures, bleeding from large arteries usually stops because the blood collects in the tissues and pressure builds up. Also it is usually possible to apply external pressure to the bleeding point(s). Because the abdomen is such a big cavity this may not happen with pelvic fractures.
Pressure suits (MAST suits) have been used to help with this problem but the results have not been predictable. In some cases, reducing the fracture with a pelvic sling or a circular bandage around the pelvis helps. In others, the radiologist can identify the bleeding point by angiography and stop the bleeding by blocking the blood vessels with blood clot (this is referred to as embolization). In some situations it is necessary to undertake emergency surgery on the bleeding area and either repair the vessels or pack the region to apply local pressure. Where dangerous bleeding is suspected from a pelvic fracture it is important to continue to monitor the patient for blood loss in case it starts again.
Open fractures of the pelvis are uncommon but fractures that are associated with injuries to the bladder, urethra or rectum are more common. These injuries require emergency surgery and may require the expertise of a general surgeon, a urologist and an orthopaedic surgeon. Any dead or contaminated tissue must be removed and the fracture should be stabilized. Sometimes this can be done provisionally with external fixation without disturbing the blood supply of the fracture any further or undertaking an big surgical exposure in a critically injured patient.
Many unstable pelvic ring fractures can be treated by an external fixation apparatus. This requires an anesthetic. Threaded metal pins are screwed into strong intact areas of the pelvis, usually the iliac wings, on both sides. The pins are then attached to a frame which bridges over the abdomen in the front. The frame can be used to reduce the fracture, close up a straddle injury or bring down part of the pelvis which has moved up. However, it cannot be used for all pelvic fractures; if there is an extensive unstable posterior injury a frame may be insufficient to keep the bones in place.
Because a frame can be applied relatively quickly without any further damage to the blood supply of the area it may be possible and desirable to combine external fixation with other forms of treatment such as traction or minimally invasive fixation. External fixation may be complicated by pin track infection and is avoided by some surgeons for this reason.
Minimally Invasive Surgery
Using the fluoroscope and employing indirect manipulation of the fracture fragments with fixation through the skin without opening up the fracture site is a technique which is attracting a lot of attention. The concept is known as minimally invasive surgery. In the context of pelvic fractures it can be employed to fix fractures of the sacrum and the ilium. Where there is an unstable pelvic ring fracture it may be possible to stabilize it by inserting sacral fixation posteriorly and using an external fixation frame anteriorly, saving the patient a more extensive operation.
Open Reduction and Internal Fixation (ORIF)
There are some situations where surgery is performed on a pelvic fracture to move the fracture fragments back into the correct position (open reduction) and fix them there with metal implants (internal fixation) until the bones heal. The implants may be pins, wires, screws or plates in any combination.
The simplest form of ORIF of a pelvic fracture is probably where there has been a posterior fracture dislocation of the hip. A fragment of the posterior lip of the hip socket is broken off with this injury as the head of the femur is driven backwards into the buttock. The exposure of this fracture is relatively straightforward and usually the hip can be put back in the socket without difficulty. The fracture fragment can then be reduced exactly and fixed with a single screw. If it is large then multiple screws or a small plate can be be used.
Displaced avulsion fractures may also be treated by ORIF. In the case of a pull-off fracture of the anterior inferior iliac spine the bone fragment may be pulled too far down into the thigh to heal. The operation requires exposing the fracture site, replacing the fragment with its muscle attachment back where it came from and holding it, usually with a single screw from the fragment into the ilium.
Another use for ORIF in pelvic fractures is the straddle injury. If the posterior elements are partially injured this fracture can be stabilized successfully by a plate across the pubic symphysis. The outer or superior surfaces of the pubic rami are exposed, the diastasis is reduced bringing the two pubic bones back together and a plate is fixed across the gap keeping the bones together until they heal.
By far the most complicated situation in which ORIF is used, is a fracture of the acetabulum. This injury breaks the hip socket, damaging the joint surface on which the femoral head moves. Although the bone is very likely to heal, if ridges, steps or gaps remain in the hip socket the hip will rapidly wear out. The intent of the surgery is to restore the smoothness of the inside of the hip socket. There are several different fracture patterns which disrupt the hip socket so the surgeon must be very familiar with the classification of the injury and the various methods of reducing the fragments and fixing them in place.
Nearly all these methods require extensive exposure of the pelvis from the front or the back of the hip joint. When ORIF of an acetabular fracture is required, it is best to have the surgery undertaken at a trauma center with experience in the procedure.
Once the fracture has healed the pelvis is stable once more. External fixation devices (pins and frame) are always removed. Internal fixation devices (implants, pins, plates, screws) may also be removed if they are causing symptoms. There may be tenderness over the metal implants or a vague aching pain. Sometimes the protruding ends of screws or pins cause catching or grating.
Many patients are very concerned about hardware removal, fearing the same post operative pain that occurred after the initial operation. In general, hardware removal is a more minor operation which can be performed as day surgery and which is followed by rapid recovery. The bone does not have to heal and the soft tissue damage that goes along with a fracture is not repeated when the implants are removed. However, removal of plates and screws from an acetabular reconstruction operation may require a big exposure once more, making it a significant undertaking. Hardware removal is not necessary if there are no symptoms.