Bone Fracture - Pelvic Acetabular Trauma
Pelvic fractures and acetabular fractures are among the most serious injuries treated by orthopedic surgeons. Often the result of a traumatic incident such as a motor vehicle accident or a bad fall, these fractures require rapid and precise treatment and, in some cases, one or more surgical procedures. People of all ages are vulnerable to these injuries. In addition, some elderly patients with fragile bones due to osteoporosis develop pelvic fractures and fractures of the acetabulum with a lower impact fall.
The complex nature of these fractures can be better understood by looking at the anatomy that is involved. The pelvis is made up of several bones (ileum, ischium and pubic bones) which create a bony ring, meeting at the pubic symphysis in the front and the sacrum (a bone situated at the lower end of the spine) in the back. Together with a number of ligaments and muscles, the bones of the pelvis support the weight of the upper body and rest on the hip joints. The pelvis protects abdominal organs including the intestines and the bladder, as well as major nerves and blood vessels. Pelvic fractures may occur at any location on the bones depending on the nature of the accident and the areas of impact.
The acetabulum refers to the part of the pelvis that meets the upper end of the thigh bone (the femoral head) to form the hip joint. In a healthy hip, these two bones fit together like a ball and cup, in which the ball rotates freely in the cup. Cartilage lines the bones where they meet at the joint and there is little friction between the surfaces during movement.
The term broken hip usually refers to a fracture of the ball portion of this joint, that is, the upper femur, femoral neck or the femoral head. In this section, we are speaking specifically of a fracture of the cup or acetabulum. Fractures of the acetabulum are harder to treat because access to this bone is more difficult, and because of the acetabulum's proximity to the major blood vessels to the legs, the sciatic nerve (the major nerve that arises from the lower spine and provides sensation and movement to the leg and foot), the intestines, the ureter and the bladder. Unlike a hip fracture, which can be treated relatively easily, to repair an acetabular fracture, the orthopaedic surgeon, must, in essence, fix the broken bones from the inside out.
In fractures of this type, the femoral head is often driven through the acetabulum because of the impact of the fall or accident. If the femoral head ends up outside the acetabulum, this is known as a dislocation of the hip joint. Some patients have both a fracture and a dislocation.
As with any fracture, the main goal of treatment for fractures of the acetabulum and pelvis is to return the patient to their pre-injury functional level, to the greatest extent possible. This means returning comfortably to daily activities--work and play. Physicians, nurses and rehabilitation specialists design a course of treatment that seeks to get the patient back to full strength and with the range of motion that they had before the injury.
To achieve these goals, proper alignment of the bones during healing is vital. Patients with acetabular and pelvic fractures often have displacement. In other words, the bones are not in proper position and must be realigned, or put back into place. Physicians use the term reduction to describe this process.
If a joint surface malheals (i.e. with irregularities), the cartilage that lines the joint will rub together and wear down, setting the stage for severe arthritis of the joint, loss of motion, decreased function and pain.
Treatment for patients with pelvic fractures is based on a number of factors including the type of fracture, the stability of the pelvis, and the degree of displacement of the bones. The orthopaedic surgeon uses information gathered through physical examination, conventional radiographs and CT scans to make this determination. Patients with a stable pelvic fracture--without displacement or dislocation--are the most likely candidates for non-surgical treatment. Some may require closed reduction (realignment without an open surgical procedure) under anesthesia with or without external fixation.
Some patients with fractures of the acetabulum may also be treated non-surgically. Usually, this treatment is selected for patients who do not have displacement and/or those who may not be able to tolerate surgery, such as individuals with significant medical problems, infections or severe osteoporosis. Closed reduction is done either through manipulation conducted while the patient is under anesthesia or by putting the patient in traction.
Realignment of the bones may be done either as an open reduction, in which the orthopaedic surgeon makes an incision to directly manipulate the bone, or as a closed reduction, in which this incision is not necessary. Once the bones are realigned, the surgeon uses internal or external fixation to hold the bone in proper position during healing. Metallic devices including wires, pins, screws, and plates are used.
Patients with pelvic fractures may require one or more surgical procedures. The surgeon may begin with an External Fixation (Ex-Fix) technique in which an open or closed reduction is performed and the bones are then held in place using an external fixator, or frame. This is done by threading pins into the bone on either side of the fracture. These pins are then connected to rods outside the skin, which form a frame.
While the Ex-Fix technique is sometimes the only procedure needed to repair a fractured pelvis, some patients require additional surgery or surgeries in which plates and screws are used internally to hold the bones in place. Depending on the site and complexity of the fracture, the surgeon may have to fix the front of the pelvis, the back of the pelvis, or both. Separate operations may be needed for each area that needs treatment.
Patients with acetabular fractures often require an Open Reduction with Internal Fixation (ORIF), especially those patients who also have displacement of the joint. The surgeon realigns or reduces the bones as precisely as possible to prevent the development of post-injury related problems, especially arthritis. The bones are rigidly fixed with plates and screws to prevent future displacement and allow for rehabilitation to begin as quickly as possible.
Fractures of the acetabulum are usually not treated for 5-10 days following the injury. Because the patient experiences significant bleeding with this fracture, the orthopaedic surgeon must wait for the patient's own clotting mechanisms to go into effect--usually within 3-5 days. During this period the patient may be in traction to prevent additional injury.
The outcome of surgery for a pelvic or acetabular fracture is dependent on a variety of factors including: the extent of injury including injuries to the head and other organs, the health of the patient prior to the injury, and whether this is the patient's first surgery for the condition.
Pelvic fractures and the multiple injuries that often go along with them are potentially life-threatening. In addition, unfortunately, even those patients who survive these injuries and whose bones are successfully realigned and healed, may have a significant degree of long-term disability, and chronic pain is not uncommon. Many have injury to the genitourinary system that can result in incontinence and impotence. The best chance for a good recovery lies in receiving excellent care from specialists who are experienced in rapid decision-making following a traumatic accident.
By itself, a fracture of the acetabulum is generally not a life-threatening injury. (Of course, some patients with these fractures will also have other serious injures.) And, thanks to advances in treatment over the years, especially surgical reduction and stabilization techniques, 80-85% of patients, can expect a good to excellent recovery following surgery, provided that the hip can be properly aligned and fixed.
On the second day following surgery for an acetabular fracture, patients are usually able to get out of bed. Crutches must be used for 8 weeks following surgery, but by 12 weeks most people are able to walk unassisted. If they are otherwise in good condition, most people recover fully within 4-6 months and are able to resume recreational activities at that time.
For individuals who have received initial treatment for their pelvic and acetabular fractures elsewhere, who have not healed properly, and are now seeking corrective surgery, a complete recovery can be more difficult to achieve. But previous surgery is not necessarily an obstacle to a good outcome following a second surgery, but this requires an experienced team, as this is the most complicated and difficult surgery of all.
While many of us have become accustomed to the amazing strides achieved by medical science, it's worth noting that these good results following acetabular fractures are remarkable. This progress is due in large part to long-term studies conducted by two French researchers, Judet and Letournel, who identified the common fracture problems and provided key information on the best way to gain access to the fracture with the least amount of injury to the patient. Based on their findings, better instruments and surgical techniques have evolved. Physicians also have a better understanding of how to avoid complications and of the healing process. More recently, additional information about the fracture is achieved through visualizing techniques such as CT and MRI scans. Before any of these developments occurred, patients with acetabular fractures had a far less promising outlook. Most ended with painful arthritic hips, and in young patients a hip bone fusion, which resulted in drastically limited mobility.