Avascular necrosis (AVN), also called Osteonecrosis of the hip or aseptic necrosis, develops when the blood supply to the femoral head is disrupted. Without adequate nourishment, the bone in the head of the femur dies and gradually collapses. As a result, the articular cartilage covering the hip also collapses, leading to disabling arthritis.
Causes of Avascular Necrosis
It is not always known as to why a person would develop AVN but there are a number of risk factors that can make it more likely for someone to develop the disease:
- Injury — Hip dislocations, hip fractures, and other injuries can damage the blood vessels and impair circulation to the femoral head
- Corticosteroid medicines — Many diseases, such as asthma, rheumatoid arthritis, and lupus, are treated with steroid medications. Although it is not known exactly why these medications can lead to osteonecrosis, research shows that there is a connection between the disease and long-term steroid use.
- Other medical conditions — Osteonecrosis is associated with other diseases, including Caisson disease (diver’s disease or “the bends”), sickle cell disease, myeloproliferative disorders, Gaucher’s disease, systemic lupus erythematosus, Crohn’s disease, arterial embolism, thombosis, and vasculitis
Although osteonecrosis affects people of all ages, it most commonly occurs between the ages of 40 and 65. Men develop osteonecrosis more often than women.
Osteonecrosis can progress through various stages, lasting several months to a year. Hip pain is typically the first symptom. This may lead to a dull ache or throbbing pain in the groin or buttock area. As the disease progresses, it will become more difficult to stand and put weight on the affected hip, and moving the hip joint will be painful.
It is important to diagnose this disease early, because some studies show that early treatment is associated with better outcomes. Surgical and non-surgical options are available.
For more specific information, please check with your provider.
Source and for more information regarding this condition: American Academy of Orthopaedic Surgeons (AAOS)