First, let’s define osteonecrosis of the hip. An understanding of this condition helps explain why treatment is important and what treatment works best. Osteonecrosis of the femoral head refers to death of the round ball of bone at the top of the femur that fits into the hip socket. Another term used for osteonecrosis is avascular or ischemic necrosis. Avascular and ischemic both mean a loss of blood supply to the area is the cause of the problem.
All of the blood supply comes into the ball that forms the hip joint through the neck of the femur (the femoral neck), a thinner area of bone that connects the ball to the shaft. If this blood supply is damaged, there is no backup. Damage to the blood supply can cause death of the bone that makes up the ball portion of the femur. Once this occurs, the bone is no longer able to maintain itself.
When osteonecrosis (or avascular necrosis) occurs in the hip joint, the top of the femoral head (the ball portion) collapses and begins to flatten. This occurs because this is where most of the weight is concentrated. The flattening creates a situation where the ball no longer fits perfectly inside the socket. Like two pieces of a mismatched piece of machinery, the joint begins to wear itself out. This leads to osteoarthritis of the hip joint, and pain.
Treatment can range from minimal intervention for mild disease in patients with no symptoms to total hip replacement for those with bone death and deformity of the entire joint. Since you have “mild” disease, we will focus on that and with your interest in a nonsurgical (no surgery), nonpharmacologic (no medications) approach, here’s what we can tell you.
Experts say (from evidence in long-term studies) that nonoperative treatment for osteonecrosis of the hip has a very poor result. Conservative care begins with taking weight off the hip. This can be done using canes, crutches, walking sticks, or a walker. The idea is to slow the disease process and preserve the femoral head.
Does it work? Not very well. One-third of patients with early, mild disease can benefit from this type of treatment. The chances of this approach being effective are increased when the patient has a small lesion located on the medial side of the femoral head (side closest to the other hip). The majority (two-thirds) end up with a collapsed femoral head.
Other types of noninvasive treatment that have been tried with this condition include electrical stimulation, shock-wave therapy, and hyperbaric oxygen. These methods are designed to stimulate bone growth. Results are mixed and no one approach has proven perfect. So, these treatments remain in the category of experimental or “under investigation”.
Talk with your surgeon about your desire to approach this problem in a conservative fashion. Your diagnosis of “mild” disease gives you an advantage. Make sure you understand all of the pros and cons of any treatment you choose to follow. And consider long-term effects on your hip, your health, and your quality of life when weighing the plusses and minuses of conservative versus surgical treatment.