Vol. 21 • Issue 17
Gait and Balance
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Avascular necrosis (AVN) is a disease resulting from the loss of the blood supply to the bones. When the blood supply is affected, the bone tissue dies and the structure of the bone begins to collapse. This disease most often affects the head of the thigh bone (femur), causing pain in the groin, and the pain may extend down the thigh.
AVN causes bone destruction, pain and loss of joint function. According to the American Academy of Orthopedic Surgeons, 10,000 to 20,000 people from 20 to 50 years of age develop avascular necrosis every year.
This is a disability that affects men as well as women.1In researching this disease, avascular necrosis of the bone was often referred to as aseptic necrosis, ischemic necrosis, or osteonecrosis.2The diagnosis of AVN begins with a medical history and physical examination. To determine the cause of pain, the individual's doctor needs to discover the signs and symptoms.3Magnetic resonance imaging (MRI) is a non-invasive test used to determine the tissues, bones, and organs that are affected as well as the progression of the disease.1
In order to diagnose my disease, an MRI was ordered. Results of my test identified avascular necrosis of the posterior and lateral aspects of the femoral head with involvement of 40 to 50 percent of the articular surface.
Researching Treatment Options
The purpose of researching treatment options is to understand the benefits and risks of each type of surgery. As a patient, it is important to know the success rate, the pain involved, the recuperation time, and length of disability.
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Before making a decision about surgery, a patient needs to research the topic, obtain facts from reliable sources and discuss all information with the orthopedic surgeon and internist. Then, the patient is prepared to make a final decision.
The goal in treating avascular necrosis is to improve the affected joint, reduce the risk of further damage to the bone, diminish pain and limitation of movement, and ensure bone and joint survival.1According to research, non-surgically managed cases most often show an 85 to 92 percent risk of progression of the disease. For this reason, it is best to treat the hip surgically.4My pre-operative condition required non-weight bearing activities to minimize the disease progression. Using crutches to prevent weight bearing on the hip, prior to surgery, reduced my risk of having multiple broken bones. I chose to have non-elective emergency surgery to avoid critical injury and alleviate severe pain.
The diagnosis of avascular necrosis revealed that I had cellular death of bone due to the loss of the blood supply. Most surgeries are elective to correct a non-life threatening condition, and are carried out at the patient's request. In these cases, there are no restrictions. The patient can have total weight-bearing activities prior to surgery.5Ramin Ganjianpour, MD, orthopedic surgeon on staff at Providence Holy Cross Medical Center in Mission Hills, CA, performed the minimally invasive hip replacement. This surgery included the removal of the affected hip, which was replaced with an artificial rod and socket that was placed through an incision only three inches long. For total hip replacement, the standard incision ranges from 8 to 16 inches in length. In comparison, the minimally invasive surgical technique requires less cutting, and results in less pain, a faster recuperation time and a better cosmetic result.6
Physical therapy in the hospital starts the day after surgery. The goals of physical therapy during the acute care period are to increase mobility, teach the patient the exercises and precautions and prepare the patient for discharge.7
Before returning home, the patient practices getting in and out of bed and walking with a walker or crutches. The patient is also taught how to use his new hip safely. Recovering at home and using a home health agency is beneficial. Home care provides nurses, occupational therapists, physical therapists and educational materials. While receiving home care services, the patient remains under the physician's care.8
Customized Physical Therapy
For an outpatient, one month after surgery, an evaluation with a standardized physical therapy assessment is typically conducted. The patient's body position and weight-bearing safety measures are discussed. Understanding the hip replacement precautions (avoiding certain positions and movements) and limiting how much weight the patient puts on his operated leg (weight-bearing) is determined by the orthopedic surgeon.9
The physical therapist instructs the patient on exercises to strengthen muscles and improve range of motion. The patient specifically learns how to move, while maintaining hip precautions.
In my case, the physical therapy program was maintained twice weekly for a total of seven months. This program increased range of motion, balance and gait speed and the stride reached normal levels. The rehabilitation protocol combined with a home exercise program twice daily led to a quicker restoration of a normal gait after my surgery.
There are many theories about the causes of avascular necrosis. The traumatic type is caused mostly by a displaced fracture affecting the hip.
A nontraumatic type may be caused by a disease that results in blockage of blood vessels supplying blood to the bone. Approximately 20 percent of all people diagnosed with AVN have an idiopathic or unknown cause of the disease.2
Active for Life
The good news is that AVN is treatable. By researching the disease, following medical advice and knowing the hip replacement precautions, I reduced my chances of undergoing a second surgery. Being diagnosed with AVN, I learned that there are many simple things a patient can do. Occupational therapists taught me how to do activities of daily living. In addition, a physical therapist showed me a program to rebuild strength and endurance. Using crutches, a walker, and a cane was challenging.
I followed up with my physicians and made a consistent effort to maintain daily physical therapy exercises. Overall, I had a medical team that provided me with the best treatment plan. Now I am active for life and enjoying a lifestyle of fitness and health.
1. National Institutes of Health. (2009). Questions and answers about osteonecrosis (avascular necrosis). Retrieved from http://www.niams.nih.gov
2. Steinberg, M. (2008). The Merck Manual. Osteonecrosis (avascular necrosis of bone; aseptic necrosis; ischemic necrosis; osteochondritis dessecans). Retrieved from http://www.merck.com
3. Mayo Foundation for Medical Education and Research. (2009). Avascular necrosis. Retrieved from http://www.mayoclinic.com/health/avascular-necrosis
4. Penn State Orthopedics. (2006). Health & disease information. Retrieved from http://www.hmc.psu.edu/healthinfo
5. Encyclopedia of Surgery. (2010). Hip replacement surgery. Retrieved from http://wwwsurgeryencyclopedia.com
6. Thompson, M. (2003). Joint undertakings longer lasting knee and hip replacements and streamlined operations improve options for osteoarthritis sufferers. Daily News. Retrieved from http://www.thefreelibrary.com
7. Freburger, J. (2000). An analysis of the relationship between the utilization of physical therapy services and outcomes of care for patients after total hip arthroplasty. Physical Therapy, 80, 5.
8. Providence Home Care. (2009). Home care hand book.
9. Krames. (2003). After total hip replacement. Living with your new hip. The StayWell Company: San Bruno, CA.
Paula Miller is a health educator for the Los Angeles County Department of Public Health.