Avascular necrosis of the hip occurs mostly in the hip joint. For some reason, blood circulation stops in the femoral head and the bone under the articular cartilage begins to lose its function and eventually fails.
What is Avascular Necrosis of the Hip?
It is the deterioration of the bone and cartilage structure that occurs in the femoral head of the hip joint for various reasons. The incidence of hip avascular necrosis has recently increased as a side effect of corticosteroid therapy used in the treatment of Coronavirus. There are 20,000 new cases per year in the United States. It is more common in men than in women. It is more common between 35 and 50 years of age. 80% have it in both hips. 3% have involvement in different joints (such as knee, shoulder).
Why is Avascular Necrosis of the Hip Important?
It is important because it causes pain, limitation of movement and calcification after deterioration in the femur bone and articular cartilage that form the hip joint.
Why Does Avascular Necrosis of the Hip Occur?
It is thought to occur after obstruction or insufficiency in the blood flow of the vessels feeding the femoral head. After radiation therapy, blood diseases such as leukemia, lymphoma, alcoholism, after cortisone therapy, in systemic lupus erythematosus disease, after marrow transplantation, with viral diseases (CMV, hepatitis, HIV, rubella, rubella, chickenpox), after HIV drug (protease inhibitor) use, Association with GAUCHER disease, abnormal loading of the joint after a traumatic event, after dislocation or fracture surgery, sickle cell anemia, autoimmune disorders, diseases with hypercoagulation (coagulation disorder), stroke disease seen in diversIt can occur secondary to various risk factors such as
How is it diagnosed?
Initially there is vague hip pain. As the load is applied, the pain increases and over time, degeneration occurs and hip joint movements are restricted. MRI of the hip is very useful for early diagnosis. In the middle/late disease stage, the diagnosis can be made with X-rays.
Is There Treatment?
Treatment is generally related to the treatment of the disease causing osteonecrosis.
As a drug treatment, analgesics and bisphosphonate therapy can be tried to prevent bone collapse. Surgical treatment is required in cases where the collapse of the bone under the cartilage causes calcification that continues with disruption of the anatomy of the femoral head.
In surgical treatment; 8-10 mm holes can be drilled into the bone with core de compression application and applied before collapse occurs under the cartilage in early onset avascular necrosis and intra-bone pressure can be reduced, bone graft application can be added to this application. This procedure reduces pain in the hip and stimulates angiogenesis and healing response.
Rotational osteotomies of the femoral head can also be used to prevent weight bearing of the lesioned part and transfer the load to healthy bone and cartilage.
With vascularized free fibula transfer surgery, the necrotic part can be removed and replaced with vascularized fibula bone transfer to prevent collapse of the head. With this technique, 80% success has been achieved in 5-10 years of follow-up.
In the last period, total hip prosthesis will be performed in patients with progressive hip joint calcification and the pain and movement limitation of the patients will be eliminated to a great extent. Avascular necrosis accounts for 10% of hip replacement surgeries.