Fractures of the pelvis and acetabular Surgery 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, pelvic and acetabular 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.