Avascular Necrosis

Avascular necrosis (AVN), also known as osteonecrosis, is a condition where bone tissue dies due to interruption of blood supply. When this occurs in the hip, it most commonly affects the femoral head (the ball of the hip joint), leading to bone death, structural collapse, and eventually hip arthritis.

The condition progresses through stages: initially, the bone loses its blood supply and begins to die; as the dead bone weakens, the femoral head may collapse under the weight of the body, causing severe pain and loss of function. If left untreated, AVN almost always leads to advanced arthritis requiring joint replacement.

At Mountain Spine & Orthopedics, our hip specialists use advanced imaging including MRI to detect AVN in its early stages, before collapse occurs. Early diagnosis is crucial, as joint-preserving treatments like core decompression are most effective when the femoral head is still intact.

• Groin pain that may be gradual in onset or sudden and severe
• Pain that worsens with weight-bearing and improves with rest
• Stiffness and reduced range of motion in the hip
• Pain that may radiate to the thigh or buttock
• Limping due to pain and difficulty bearing weight
• In advanced stages, constant pain even at rest
• Difficulty with activities like walking or climbing stairs

Several factors increase the risk of developing avascular necrosis:

• Long-term use of corticosteroid medications, which is one of the most common causes
• Excessive alcohol consumption, which can damage blood vessels
• Previous hip injuries or trauma, including hip fractures or dislocations
• Certain medical conditions like sickle cell disease, lupus, or blood clotting disorders
• Radiation therapy to the hip area
• Decompression sickness (the bends) in divers
• Certain medications or treatments that affect blood supply

Early diagnosis is critical for successful treatment. Diagnosis begins with a thorough medical history and physical examination to assess symptoms and identify risk factors.

We offer a complimentary MRI review, which is the most sensitive test for detecting AVN in its early stages, before changes are visible on X-rays. X-rays are useful for assessing the extent of collapse once the condition has progressed. CT scans or bone scans may also be used to evaluate the extent of bone involvement and guide treatment planning.

Non-Surgical Treatment Options

In early stages, conservative measures may include activity modification to reduce weight-bearing stress on the hip, physical therapy referrals to maintain range of motion, and medications to manage pain. However, these measures typically do not stop disease progression.

Surgical Treatment Options

For patients with early-stage AVN before collapse occurs, core decompression may be performed to relieve pressure and stimulate new blood vessel growth. This procedure involves drilling into the femoral head to reduce pressure and promote healing.

For advanced cases with collapse or when joint-preserving procedures are not possible, total hip replacement is the definitive treatment, providing excellent pain relief and restoring function. In some cases, hip resurfacing may be considered for younger, active patients.

Avascular necrosis pain typically begins as a dull ache in the groin that worsens with activity. As the condition progresses and the femoral head begins to collapse, the pain becomes more severe and constant, often described as a deep, grinding pain.

The pain is usually worse with weight-bearing activities and may persist even at rest in advanced stages. Our treatment approach focuses on preserving the joint when possible through early intervention, or providing definitive relief through joint replacement when the joint has collapsed.

While some risk factors for AVN cannot be avoided, several strategies can help reduce risk:

• Using corticosteroid medications only when necessary and at the lowest effective dose
• Limiting alcohol consumption to reduce vascular damage
• Seeking prompt treatment for hip injuries or trauma
• Managing underlying medical conditions that may affect blood supply
• Regular monitoring with imaging if you have risk factors for AVN
• Seeking early evaluation from a hip specialist if you experience hip pain and have risk factors
• Maintaining overall vascular health through exercise and healthy lifestyle

If you're experiencing hip pain and have risk factors for avascular necrosis, schedule a consultation with Mountain Spine & Orthopedics today. Early diagnosis is crucial for successful treatment. Benefit from a complimentary MRI review and expert evaluation. Same-day and next-day appointments are often available.