Avascular Necrosis of the Hip

Avascular Necrosis of the Hip

As stated above, avascular necrosis has many causes. In fact, most researchers believe that the condition is caused by a constellation of factors acting at once to create the perfect storm. This condition can occur in children or adults and can be caused by medications, conditions, or other factors.

Two common causes that cause avascular necrosis are glucocorticoids and alcohol. Glucocorticoids, commonly known as steroids, are used to treat many medical conditions. In some people, they can impair blood flow to the femoral head and cause necrosis of the bone. Excessive alcohol use also causes avascular necrosis. Scientists believe this is due to changes in stress levels, an increase in fat, and sluggish blood flow.

Many medical conditions are associated with avascular necrosis of the hip. These include Lupus, the presence of antiphospholipid antibodies, Sickle Cell Disease, Gaucher Disease, Decompression Disease, Acute Lymphoblastic Leukemia, and kidney transplants. Avascular necrosis in children can be due to a congenital condition called Legg-Calvé-Perthes disease. Additionally, trauma, such as falling or being hit by a car, puts both adults and children at risk for avascular necrosis.

When physicians suspect avascular necrosis, they turn to imaging. An X-ray is the best initial test and will show changes in the bone that are characteristic of avascular necrosis. The physician then orders Magnetic Resonance Imaging (MRI). An MRI can accurately visualize the necrotic bone and confirm the diagnosis.

Avascular necrosis can be difficult to treat depending on the patient. The first step is to identify the cause of the necrosis and stop or manage the offending agent. This also includes optimizing other risk factors that impede blood flow, including smoking. Early in the disease, some physicians recommend starting with non-operative management. Non-operative management includes reducing weight-bearing by using crutches and using medications to reduce pain and maintain bone density. However, non-operative management has been found to be ineffective at halting the progression of the disease. Therefore, many people turn to operative management.

Operative management can be divided into two classes: joint-preserving procedures and joint replacement procedures. One option for a joint-preserving procedure is called core decompression. This is when the surgeon uses a tool to decompress the femoral head to restore blood flow. They often then use a bone graft to fill in the parts of the bone that have died.

Researchers have examined the success rate of core decompression with and without bone grafting have mixed results. Many studies have demonstrated that patients have significant pain relief with core decompression. Only certain patients reported excellent outcomes from core decompression, particularly those that had the procedure done early in the disease before the bone collapsed. Other patients had less success.

When joint-preserving procedures are not successful, the next option is a joint replacement. Total hip replacements are generally successful with a low revision rate. Because the revision rate is low, some surgeons prefer total hip replacements over joint-preserving procedures. Other surgeons prefer to be more selective with who receives a total hip replacement depending on their disease progress and lifestyle.

Avascular necrosis of the hip is a condition that causes pain and reduced mobility of the hip. Treatment is complicated and depends on the patient, his or her lifestyle, and his or her risk factors. If you suffer from avascular necrosis of the hip, schedule an appointment to talk with Dr. Morton to determine the best course of action for you.