Femoral Head Avascular Necrosis Treatment

What Is Avascular Necrosis of the Femoral Head?

Avascular necrosis literally means “death due to lack of blood supply.” In avascular necrosis of the femoral head, blood flow through the small vessels that nourish the femoral head is disrupted. Bone cells that do not receive enough blood die. Although dead bone tissue may initially appear intact, over time it loses its structural integrity and becomes mechanically weak. Under normal loads such as body weight, this weakened bone is crushed and collapses. The spherical shape of the femoral head becomes distorted and flattened, and the cartilage on the joint surface is also damaged. This condition leads to severe pain and permanent loss of function.

What Causes Avascular Necrosis? Risk Factors

There are many factors that can disrupt blood flow to the femoral head:

1. Traumatic Causes:
   
   • Hip Fractures: Femoral neck fractures in particular can damage the vessels that supply the femoral head, increasing the risk of avascular necrosis.
   • Hip Dislocation: During a traumatic hip dislocation, the blood vessels can be stretched or torn. A delay in reducing (relocating) the dislocation increases the risk of avascular necrosis.
2. Non-Traumatic Causes:
   
   • Corticosteroid (Cortisone) Use: Long-term or high-dose systemic (oral or intravenous) cortisone use is the most common non-traumatic cause. Although exactly how cortisone disrupts blood flow is not fully understood, it is thought to cause fat emboli in small vessels or an increase in intraosseous pressure.
   • Excessive Alcohol Consumption: Chronic and excessive alcohol use also significantly increases the risk of avascular necrosis.
   • Medical Conditions:
     
     • Blood disorders such as sickle cell anemia
     • Blood clotting disorders (thrombophilia)
     • Storage disorders such as Gaucher disease
     • Autoimmune diseases such as systemic lupus erythematosus (SLE)
     • Pancreatitis
     • HIV infection
     • Decompression sickness (caisson disease)
   • Radiotherapy: Radiotherapy applied to the hip region.
   • Smoking: May increase the risk by constricting blood vessels.
   • Idiopathic: In some cases (around 20-30%), no underlying cause can be found, and the avascular necrosis is classified as “idiopathic” (of unknown cause).

Symptoms and Stages of Avascular Necrosis

The symptoms of avascular necrosis usually begin insidiously and vary depending on the stage of the disease:

• Pain: The most common and usually the first symptom. It typically begins in the groin area, but may radiate to the side of the hip, the thigh, or the knee. At first, pain occurs only with weight-bearing (walking, standing), but as the disease progresses, pain may also occur at rest and at night. A sudden increase in pain may occur when the femoral head collapses.
• Limping: Limping may develop due to pain or due to leg-length discrepancy (following collapse).
• Restricted Movement: As the disease progresses, restriction develops in hip joint movements, particularly internal rotation and abduction (moving the leg outward).

Staging of Avascular Necrosis: Treatment of avascular necrosis largely depends on the stage of the disease. Staging is generally based on X-ray and MRI findings (using systems such as Ficat or ARCO). In simplified terms, the stages can be summarized as follows:

• Stage 0/I (Pre-radiographic): X-ray is normal. Diagnosis can only be made with MRI or bone scintigraphy. The bone has begun to lose viability, but there is no collapse. This stage is the most suitable time for hip-preserving treatments.
• Stage II (Pre-collapse): Changes in bone density (cysts, sclerosis) are seen on X-ray, but the spherical shape of the femoral head is still preserved and collapse has not yet begun. Joint-preserving treatments can still be attempted.
• Stage III (Early Collapse): A small collapse line (“crescent sign”) or slight flattening is seen at the top of the femoral head on X-ray. The joint space is generally not yet narrowed. At this stage, the success rate of joint-preserving treatments decreases significantly.
• Stage IV (Advanced Collapse / Osteoarthritis): The femoral head has collapsed markedly and its shape is distorted. The joint space is narrowed, and cartilage damage and osteoarthritis (secondary arthrosis) have also developed in the acetabulum (socket). At this stage, the only effective treatment is generally hip replacement surgery.

How Is Avascular Necrosis Diagnosed?

Since early diagnosis is critical for treatment success, avascular necrosis should be suspected in patients with risk factors or unexplained hip/groin pain.

• Detailed History: The onset, character, and severity of the pain, and in particular the presence of risk factors (cortisone use, alcohol, history of trauma, other conditions), are carefully questioned.
• Physical Examination: Hip range of motion (especially restricted internal rotation), painful movements, and gait pattern are assessed. Examination findings may be normal in early stages.
• Imaging Methods:
  
  • X-ray: The first test requested. May be normal in early stages. In advanced stages, it shows changes in bone density, the crescent sign, collapse of the femoral head, and signs of osteoarthritis. Used for staging.
  • Magnetic Resonance Imaging (MRI): The most sensitive and earliest diagnostic method for avascular necrosis. It shows bone marrow edema and the necrotic (dead) area even in early stages when X-rays show no findings yet. By determining the size and location of the necrosis, it provides important information about staging and prognosis. It is also the best method for showing whether collapse has occurred.
  • Bone Scintigraphy: Sensitive for early diagnosis, but not as specific as MRI and does not show the size of the necrosis. Can be used when MRI cannot be performed.

Treatment Options (According to Disease Stage)

The goal of avascular necrosis treatment is to relieve pain, stop the progression of the disease, prevent collapse of the femoral head, and preserve hip function. The choice of treatment is made according to the stage of the disease, the size and location of the necrosis, and the patient’s age and activity level.

Non-Surgical (Conservative) Treatment:

• Generally may be tried to relieve symptoms in very early stage (Stage 0/I), small lesions, or patients who are not suitable candidates for surgery.
• Limited Weight-Bearing: Using crutches to reduce the load on the hip.
• Medication: NSAIDs for pain. Drugs such as bisphosphonates may be tried to slow bone breakdown, but their effectiveness in avascular necrosis is debated and they are not routinely recommended.
• Treating the Underlying Cause: Such as reducing/stopping cortisone use or quitting alcohol, if possible.
• Physical Therapy: To maintain joint range of motion and support muscle strength.
• Important Note: Non-surgical treatment generally does not stop disease progression, and the risk of collapse continues.

Joint-Preserving Surgical Methods (Generally for Pre-Collapse Stages – Stage I and II):

The goal is to intervene before the femoral head collapses in order to preserve the patient’s own joint.

• Core Decompression: The most commonly performed joint-preserving surgery. The necrotic area of the femoral head is accessed by drilling one or more holes, usually through a small skin incision or with closed techniques. The purpose of this procedure is to:
  
  • Reduce the pressure within the bone (relieves pain).
  • Encourage new blood vessels and healing cells to reach the necrotic region.
  • Promote revascularization of the bone. The success rate varies according to the stage of the disease and the size of the necrosis; its effectiveness is very low once collapse has begun (Stage III and IV).
• Core Decompression + Biological Supports / Grafts: Frequently combined with additional procedures to increase the effectiveness of core decompression:
  
  • Bone Grafts: The patient’s own bone (autograft – usually taken from the pelvis) or cadaver bone (allograft) is placed into the drilled holes to provide structural support and promote bone healing. A Vascularized Fibula Graft (transfer of a segment of fibula bone from the patient’s own leg together with its blood vessel) is a complex option used for larger lesions.
  • Cell-Based Therapies (PRP, BMAC, Cultured MSCs): Injection of PRP prepared from the patient’s own blood, BMAC obtained from bone marrow, or laboratory-expanded mesenchymal stem cells into the channels created by core decompression. The goal is to more strongly stimulate bone healing and revascularization. These methods are still under active investigation; they are promising but are not a standard treatment and their results are variable.
• Osteotomies: Bone-realigning surgeries performed on the femur or acetabulum. They were used in the past in the treatment of avascular necrosis to move the necrotic area away from the weight-bearing zone, but today they are rarely chosen for avascular necrosis.

Joint Replacement (Prosthesis) Surgery (Generally for Post-Collapse Stages – Stage III and IV):

Once the femoral head has collapsed or osteoarthritis has developed in the joint, joint-preserving methods generally fail, and replacement surgery is required for a permanent solution.

• Total Hip Replacement (THR): The gold-standard treatment in advanced stages of avascular necrosis (Stage III and IV) or when joint-preserving surgery has failed. Both the femoral head and the acetabulum (socket) are replaced with artificial prosthetic components. It is extremely successful in relieving pain and restoring function. Because avascular necrosis often affects younger patients, it is important that the prostheses used in these patients are long-lasting and made from modern materials (such as ceramic and advanced polyethylene).
• Hemiarthroplasty (Partial Replacement): Involves replacing only the femoral head. Because the acetabular cartilage is also often affected in avascular necrosis, it is less preferred than total hip replacement.
• Resurfacing: A method in which the femoral head is reshaped and capped with a metal covering. It may be an option in carefully selected young, active male patients, but its popularity has declined due to complications and long-term outcomes.

Prof. Dr. Murat Bozkurt determines the most appropriate surgical method (core decompression, total hip replacement, etc.) according to the stage of the avascular necrosis and the patient’s condition, providing treatment to his patients in Ankara.

Risks, Benefits, and Recovery Process

• Benefits:
  
  • Joint-Preserving Surgery (Early Stage): The chance to preserve the patient’s own hip joint, prevent/delay collapse and osteoarthritis, and postpone the need for a prosthesis.
  • Total Hip Replacement (Advanced Stage): Definitive relief of pain, and recovery of mobility and quality of life.
• Risks:
  
  • Core Decompression: Infection, bleeding, nerve damage, femoral neck fracture, failure of the procedure with progression of the disease and development of collapse (20-50% or more, varying by stage and lesion size), and future need for hip replacement.
  • Total Hip Replacement: Standard prosthesis risks such as infection, blood clots (DVT/PE), prosthetic dislocation, leg-length inequality, loosening or wear of the prosthesis (particularly the long-term risk of revision in young patients), and nerve damage.
• Recovery Process:
  
  • After Core Decompression: Because bone healing must be awaited, protected weight-bearing with crutches for 6 weeks or longer (sometimes non-weight-bearing) is generally required. Range of motion and muscle strength are gradually regained with physical therapy. Full recovery may take several months.
  • After Total Hip Replacement: A standard hip replacement rehabilitation protocol is followed. Earlier weight-bearing is generally allowed. Function is regained through physical therapy. Recovery is generally faster than with core decompression, but the long-term lifespan of the prosthesis and activity restrictions should be kept in mind.

Avascular Necrosis of the Femoral Head Treatment in Ankara and Prof. Dr. Murat Bozkurt’s Approach

Avascular necrosis of the femoral head is a serious condition that requires early diagnosis and accurate staging, and that can lead to permanent disability if left untreated. In his approach to patients with avascular necrosis in Ankara, Prof. Dr. Murat Bozkurt focuses on the following points:

• Early Diagnosis and Identification of Risk Factors: Particularly in patients with risk factors, he keeps avascular necrosis in mind in the differential diagnosis of hip pain and aims to achieve early diagnosis with MRI when it is suspected. He investigates possible underlying causes.
• Accurate Staging: He accurately determines the stage of the disease based on MRI and X-ray findings and plans treatment options accordingly.
• Priority on Joint-Preserving Treatment (at the Appropriate Stage): In patients whose femoral head has not yet collapsed (Stage I and II), especially younger patients, he prioritizes evaluating joint-preserving surgical methods (primarily core decompression, combined with biological supports or grafts when needed). He gives patients realistic information about the chances of success and the limits of these treatments.
• Expertise in Total Hip Replacement (at Advanced Stages): In patients whose femoral head has collapsed or in whom osteoarthritis has developed (Stage III and IV), or in cases where joint-preserving treatments have failed, he successfully performs total hip replacement surgery using modern techniques and long-lasting implants to relieve pain and restore function. He takes particular care in prosthesis selection for young patients.
• Long-Term Follow-up: Because of the progressive nature of avascular necrosis and the need for follow-up after prosthesis surgery, he regularly monitors his patients.

Avascular necrosis of the femoral head is a serious condition in which the hip joint can be preserved if diagnosed early, but which can lead to permanent damage and the need for a prosthesis if diagnosis is delayed. If you have risk factors or hip pain, it is very important to consult an orthopedic specialist without delay. In Ankara, Prof. Dr. Murat Bozkurt, who is experienced in avascular necrosis, will help you develop the most suitable treatment plan for you.

For detailed information and appointments, you can contact Prof. Dr. Murat Bozkurt at 0312 502 70 74.