Acetabulum fractures often result from automobile or motorcycle accidents, falls from great heights and industrial accidents, when an accidental strong force drives the head of the femur through the acetabulum. Fractures of the acetabulum disrupt the smooth surface and precise fit of the hip joint. If the bone is allowed to heal with large gaps and irregularities, severe abrasion to and the ultimate destruction of the cartilage will result. In some cases, the bone itself will show wear.
The consequence is – severe hip arthritis. Patients who develop arthritis have pain when walking, loss of hip motion, and limited functional capabilities. Fractures of the acetabulum cause internal bleeding from the broken bone and the surrounding injured soft tissues. Major blood vessels may be torn, causing severe bleeding. There can be damage to internal organs, such as the bowel or bladder. The nerves that provide sensation and muscle function to the leg or that control bowel, bladder and sexual function may also be impaired.
Traditional treatment technique may involve traction to the leg. Recent medical studies however indicate non-operative treatment is best reserved for a minority of fractures (about 11 percent). Traction can prevent further displacement of the femur into the acetabulum but does not accurately reduce (reposition) acetabulum fractures and can lead to muscle atrophy and joint stiffness as well as a high incidence of arthritis.
Surgery is required to obtain the best possible results for the majority of patients and is recommended in most cases. Acetabulum fracture surgery preserves the hip joint by accurate reconstruction of the fractured bone. This reconstruction restores the smooth surface of the acetabulum and its accurate fit to the femoral head. In the majority of cases, arthritis is prevented and there is close to normal hip function.
For best results, surgery should take place within seven days of injury. The potential for difficulties and complications increases after three weeks. Depending on the fracture pattern, one of three surgical approaches will be chosen which will give the best access for reconstruction of the acetabulum. These include the Kocher-Langenbeck approach (posterior approach), the Ilioinguinal approach (simultaneous access to both anterior and posterior portions of the pelvic ring), and the Extended iliofemoral approach (lateral approach).
The patient is placed on a special operating table that applies traction to the leg during surgery and assists in reducing the fracture. Surgery to repair acetabulum fractures is called open reduction and internal fixation. Open refers to making an incision that exposes the broken bone fragments to view. Reduction refers to the process by which the surgeon uses specially designed instruments to grasp the bone fragments and manipulate them into their normal position. Internal fixation occurs when metal screws and plates are used to hold fractured bone fragments to the unbroken portions of the pelvis.
Screws and plates (thin strips of metal with holes to accommodate screws) fix fractured bone fragments together. Typically made of stainless steel, these implants do not react with body fluids or cause an allergic response. Implants made of vitallium or titanium is also safe and effective.