Avascular necrosis of the hip, also called osteonecrosis or aseptic necrosis of the hip, is a painful condition that occurs when the blood supply to the head of the thigh bone (femur) is disrupted.
Without an adequate blood supply, the bone in the head of the femur dies and gradually collapses, which can result in destruction of the hip joint and severe arthritis.
The cause of avascular necrosis of the hip is not always known.
Risk factors that can increase the chance of developing avascular necrosis of the hip include:
- Hip injury
- Dislocations, fractures, and other hip injuries can damage blood vessels and impair circulation to the femoral head
- Excessive alcohol use
- Over time, excessive alcohol use can cause fatty deposits to form in the blood vessels and elevated cortisone levels, which results in a decreased blood supply to the bone
- Corticosteroid use
- Certain medical conditions
What Are Symptoms of Avascular Necrosis of the Hip?
Symptoms of avascular necrosis of the hip include:
- Hip pain (usually the first symptom)
- Dull ache or throbbing pain in the groin or buttock area
- Difficulty standing and weight bearing on the affected hip
- Pain when moving the hip joint
How Is Avascular Necrosis of the Hip Diagnosed?
Avascular necrosis of the hip is diagnosed with a patient history and physical examination of the hip, including checking which specific motions cause pain.
Imaging studies are used to help confirm the diagnosis, such as:
What Is the Treatment for Avascular Necrosis of the Hip?
Nonsurgical treatments may be used to help relieve pain and slow the progression of avascular necrosis of the hip, but surgery is usually the treatment of choice to help preserve the hip.
Nonsurgical treatments used to help relieve pain and slow the progression of avascular necrosis may include:
- Anti-inflammatory medications
- Modifying activities
- Using crutches
Surgical procedures used to treat avascular necrosis of the hip include:
- Core decompression
- Holes are drilled into the femoral head to relieve pressure in the bone and create channels for new blood vessels to supply the affected areas of the hip
- Core decompression may successfully prevent collapse of the femoral head and the development of arthritis when performed early in the disease
- Osteochondral (bone and cartilage) grafting
- A bone graft is transplanted healthy bone tissue
- Tissue may be from a donor (allograft) or from another bone in the patient’s body (autograft), or a synthetic bone graft may be used
- Often combined with core decompression to help regenerate healthy bone and support cartilage at the hip joint
- Vascularized fibula graft
- A segment of bone is taken from the small bone in the leg (fibula) along with the artery and vein that are its blood supply, and is transplanted into a hole created in the femoral neck and head, and the artery and vein are reattached to help heal the area of avascular necrosis
- Total hip replacement
- Advanced avascular necrosis, where the femoral head has already collapsed, may require total hip replacement
- The damaged bone and cartilage are removed, then new metal or plastic joint surfaces are placed to restore the function of the hip