Pelvic and Acetabular Fractures

Fractures of the pelvis and acetabulum are among the most serious injuries treated by orthopaedic 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 acetabulum is the socket of the ball-and-socket hip joint. The top of the thigh bone (femur) forms the ball, and the socket (acetabulum) is part of the pelvic bone. The acetabulum is part of the pelvis. The part of the pelvis that forms the hip socket is the acetabulum. The acetabulum is round in shape, and covered inside with smooth cartilage. This cartilage forms the smooth surface of the hip joint.

Acetabular Fractures

An acetabular fracture occurs when the socket of the hip joint is broken. This is much less common than most fractures of the hip, where the ball of the ball-and-socket joint is broken.

How does an acetabular fracture occur?

Acetabular fractures either occur with high-energy trauma (e.g. auto collisions, falls, etc.) or as an insufficiency fracture. In younger patients, there is almost always significant trauma, and commonly associated injuries, when an acetabular fracture occurs. In elderly patients, acetabular fractures can occur due to bone weakened from osteoporosis.

What is the treatment of an acetabular fracture?

In patients who have a traumatic acetabular fracture, the treatment depends on the extent of cartilage displacement, and hip instability. The hip joint should be stable (the ball held tightly within the socket) and the cartilage should be smoothly contoured. Surgery is often recommended for:

• Aligning the cartilage surface
• Removing debris (bone) from within the hip joint
• Restoring stability of the hip

Elderly patients have surgery less frequently, and fractures may be allowed to heal even if the alignment is not perfect.
Whether or not surgery is performed, patients must minimize the weight they place on the affected extremity, often for up to three months. Patients are usually allowed to place their foot on the ground (touch-down weight-bearing), but no more force is allowed on the leg. Walking on the extremity too soon risks further displacement of the broken fragments of bone.

What are the complications associated with acetabular fractures?

Unfortunately, the long-term prognosis of acetabular fractures has many potential complications. In the early period, patients who have acetabular fractures often have associated injuries including head injuries, abdominal injuries, urologic injuries, and other musculoskeletal injuries (spine and knee are most common). These patients are at high risk of developing blood clots in the legs and pelvis. Patients who have surgery risk infection, nerve and blood vessel injury, and wound healing problems.
In the longer-term, the common problem is the development of hip arthritis. Patients often eventually need a hip replacement surgery. Other possible problems include hip osteonecrosis, heterotopic bone (excess bone) formation.

Pelvic Fractures

A pelvic fracture is a disruption of the bony structures of the pelvis (pelvic bone). In elderly persons, the most common cause of pelvic injuries is a fall from a standing position. However, fractures associated with the greatest morbidity and mortality involves significant forces such as from a motor vehicle crash or fall from a height.

Pelvic Fracture Symptoms

The main symptom of a pelvic fracture is pain in the groin, hip or lower back, which may get worse when walking or moving the legs. Other symptoms may include:

• Abdominal pain
• Numbness or tingling in the groin or legs
• Bleeding from the vagina, urethra (the tube that carries urine from the bladder to the outside of the body) or the rectum (the chamber that contains solid wastes from the large intestine until they are eliminated outside the body)
• Difficulty urinating
• Difficulty walking or standing
• A stress fracture that occurs while jogging may cause pain in the thigh or buttock.

Causes and Risk Factors

Most pelvic fractures occur during high-speed accidents (such as car or motorcycle crashes) or falls from great heights. Pelvic fractures can also occur spontaneously or after minor falls in people with bone-weakening diseases such as osteoporosis. Less commonly, pelvic fractures may occur during high-impact athletic activities.

Treatment of Pelvic Fractures

Pelvic fracture treatment depends on how bad the injury is. With a minor fracture, the most common treatment is bed rest, nonsteroidal anti-inflammatory medications or prescription painkillers. Physical therapy, the use of crutches and, rarely, surgery may be recommended. Healing can take eight to 12 weeks.
Severe injuries to the pelvis that involve several breaks can be life threatening. Shock, extensive internal bleeding and internal organs damage may be involved. The immediate goal is to control bleeding and stabilize the injured person's condition. These injuries often require extensive surgery as well as lengthy physical therapy and rehabilitation.
In the surgical treatment, the orthopaedic surgeon will put the pelvic bones back together and hold them in place with an internal device, such as:
Pins (surgical screws): This is used if the break is where the thighbone (femur) joins the pelvis (femoral neck fracture) and you are younger and more active, or if the broken bone has not moved much out of place. If you are older and less active, you may need a high strength metal device that fits into your hip socket, replacing the head of your femur (hemiarthroplasty).
Compression screw and side plate: This is used for an intertrochanteric fracture to hold the broken bone in place while it lets the head of your femur move normally in your hip socket. Plates and screws following surgical cleaning of the fracture and reposition of fracture fragments. This is done when the hip socket has fractured (acetabular) fractures.

Complications

Complications of pelvic fractures include the following:

• The incidence of deep venous thrombosis is increased.
• Continued bleeding from fracture or injury to pelvic vasculature may occur.
• Infections from disruption of bowel or urinary system may develop.
• Chronic pelvic pain, more so if the sacroiliac joints are involved, may occur.