Stem Cell Therapy for Avascular Necrosis of the Hip

Stem cell therapy, a form of regenerative medicine, has gained attention for its potential to treat avascular necrosis (AVN) of the hip. AVN occurs when the blood supply to the head of the femur is disrupted, leading to bone death and collapse of the joint. Stem cells, harvested from the bone marrow, fat, or blood, are injected into the affected area to stimulate bone regeneration, improve blood supply, and delay the need for joint replacement.

How Common It Is and Who Gets It? (Epidemiology)

Avascular necrosis of the hip most commonly affects individuals between the ages of 30 and 50, especially those who are physically active. It is frequently caused by trauma (fractures or dislocations), excessive corticosteroid use, or chronic alcohol abuse. In some cases, medical conditions that affect clotting or blood flow, such as lupus or sickle cell anemia, can also lead to AVN.

Why It Happens – Causes (Etiology and Pathophysiology)

The primary cause of AVN is the disruption of blood flow to the femoral head, either from trauma or non-traumatic causes. As the blood supply is reduced, bone cells die and the bone structure weakens. Over time, this leads to the collapse of the femoral head, resulting in pain, reduced mobility, and arthritis. In the early stages, bone marrow attempts to regenerate new bone, but inadequate blood flow impedes this process.

Avascular Necrosis of the head of the femur.

How the Body Part Normally Works? (Relevant Anatomy)

The hip joint is a ball-and-socket joint, where the femoral head (ball) fits into the acetabulum (socket) of the pelvis. Healthy bone is maintained through a continuous process of bone turnover, supported by a steady blood supply. The femoral head relies on vascularization to receive nutrients and maintain its structure. Without adequate blood flow, the femoral head becomes susceptible to necrosis and collapse.

What You Might Feel – Symptoms (Clinical Presentation)

Patients with AVN of the hip typically experience:

• Pain: Usually located in the groin or outer thigh, which worsens with movement or weight-bearing activities.

• Stiffness: Difficulty in moving the hip joint, particularly in activities like walking, squatting, or bending.

• Limited mobility: The inability to fully rotate or lift the leg, which significantly impacts daily activities.

• Pain at rest: In more advanced stages, pain may be constant, even during rest.

How Doctors Find the Problem? (Diagnosis and Imaging)

• Physical examination: A doctor may check for tenderness, restricted movement, and muscle weakness in the hip area.

• X-rays: Often used to rule out other conditions, though early-stage AVN may not show clear changes.

• MRI or bone scan: These imaging techniques are more effective in detecting early-stage AVN, where bone changes and damage may not be visible on X-rays.

Procedure Types or Techniques (Classification)

Stem cell therapy for AVN can be used in combination with other joint-preserving treatments, such as:

• Core decompression: Involves creating small tunnels in the femoral head to relieve pressure and stimulate blood flow.

• Bone grafting: Bone grafts can be used to help fill the void left by the dead bone and promote healing.

• Stem cell injection: Bone marrow-derived stem cells are injected into the necrotic area to stimulate regeneration and revascularization.

Other Problems That Can Feel Similar (Differential Diagnosis)

• Osteoarthritis: Causing similar pain and stiffness, but usually seen in older patients and affects the entire joint.

• Labral tear: Often causes groin pain, but this is typically related to a tear in the cartilage rather than bone damage.

• Trochanteric bursitis: Inflammation in the hip bursa causing outer hip pain, which can mimic AVN.

Treatment Options

Non-surgical treatments: Physical therapy, pain management (NSAIDs, corticosteroid injections), and activity modification are often used in early-stage AVN.

Surgical options: When symptoms persist, core decompression and stem cell therapy are considered, with hip replacement surgery reserved for more advanced stages.

Recovery and What to Expect After Surgery

• Postoperative care: Patients are typically advised to limit weight-bearing for 4-6 weeks to allow the bone to heal and the stem cells to work.

• Physical therapy: Begins shortly after the procedure, focusing on improving hip mobility and strength.

• Pain management: Post-surgical pain usually subsides within a few weeks, with most patients resuming daily activities after 3-6 months.

• Follow-up: Regular monitoring through X-rays and MRIs to assess the healing process.

Possible Risks or Side Effects (Complications)

• Infection: As with any surgical procedure, there is a risk of infection at the injection or surgical site.

• Graft failure: If bone grafts or stem cells do not integrate properly, the necrosis may progress, requiring additional intervention.

• Bone collapse: In some cases, AVN may progress despite stem cell therapy, requiring total hip replacement.

Long-Term Outlook (Prognosis)

Stem cell therapy can significantly slow or halt the progression of AVN in the early stages. While many patients experience pain relief and restored function, the long-term success depends on the severity of the AVN and the extent of bone collapse. In some cases, the disease may progress to the point where joint replacement is necessary.

Out-of-Pocket Costs

Medicare

CPT Code 38220 – Bone Marrow Aspiration (Stem Cell Harvest): $36.05

Medicare Part B typically covers 80% of the approved cost for this procedure once your annual deductible has been met, leaving you responsible for the remaining 20%. Supplemental Insurance plans such as Medigap, AARP, or Blue Cross Blue Shield generally cover that remaining 20%, minimizing or eliminating out-of-pocket expenses for Medicare-approved procedures. These plans coordinate with Medicare to fill the coverage gap and reduce the patient’s financial responsibility.

If you have Secondary Insurance, such as TRICARE, an Employer-Based Plan, or Veterans Health Administration coverage, it serves as a secondary payer. These plans typically cover any remaining balance, including coinsurance or small deductibles, which generally range from $100 to $300, depending on your plan and provider network.

Workers’ Compensation

If your bone marrow aspiration or stem cell harvest is related to a work injury, Workers’ Compensation will cover all associated medical expenses, including the procedure and any follow-up care. You will not have any out-of-pocket expenses, as the employer’s insurance carrier directly covers all approved treatments.

No-Fault Insurance

If your bone marrow aspiration is needed due to an automobile accident, No-Fault Insurance will typically cover the full cost of treatment. The only potential out-of-pocket cost may be a small deductible or co-payment depending on your insurance policy.

Example

Amy Stevens required bone marrow aspiration (CPT 38220) for stem cell therapy as part of a treatment plan for osteoarthritis. Her estimated Medicare out-of-pocket cost was $36.05. Since Amy had supplemental insurance through AARP Medigap, her remaining balance was fully covered, leaving her with no out-of-pocket expenses for the procedure.

Frequently Asked Questions (FAQ)

Q. How long will stem cell therapy last?

A. Stem cell therapy can offer relief for several years, though some patients may eventually require hip replacement.

Q. Is it effective in all patients?

A. Stem cell therapy is most effective in the early stages of AVN and may not be suitable for advanced cases.

Q. Can I return to sports after treatment?

A. Most patients can return to low-impact activities such as swimming or walking, but high-impact activities should be avoided.

Summary and Takeaway

Stem cell therapy offers a promising treatment option for early-stage avascular necrosis, providing pain relief, promoting bone regeneration, and delaying the need for hip replacement. With appropriate patient selection, this approach can significantly improve quality of life and preserve hip function.

Clinical Insight & Recent Findings

A recent study published in The Journal of Regenerative Medicine found that stem cell therapy combined with core decompression significantly improved bone healing and reduced pain in patients with early-stage AVN.

Who Performs This Surgery? (Specialists and Team Involved)

Orthopedic surgeons specializing in hip and joint preservation perform stem cell therapy procedures, often in collaboration with physical therapists and anesthesiologists.

When to See a Specialist?

Consult an orthopedic specialist if you experience persistent hip pain, especially if you have risk factors like corticosteroid use or alcohol consumption.

When to Go to the Emergency Room?

Seek medical attention if you experience sudden, severe hip pain, or if you notice signs of infection (fever, redness, swelling) after the procedure.

What Recovery Really Looks Like?

Recovery typically involves gradual weight-bearing, physical therapy, and periodic imaging to monitor progress. Most patients see significant improvement in 3-6 months.

What Happens If You Delay Surgery?

Delaying stem cell therapy or core decompression may lead to joint collapse and the need for more invasive procedures like hip replacement.

How to Prevent Recurrence or Failure?

Maintain a healthy weight, avoid high-impact activities, and continue physical therapy to ensure the best possible outcome.

Nutrition and Bone or Joint Health

A balanced diet rich in calcium and vitamin D helps support bone health. Avoiding smoking and excessive alcohol consumption can also improve outcomes.

Activity and Lifestyle Modifications

Post-treatment, engage in low-impact activities like swimming or cycling to maintain joint health, and avoid heavy lifting or running to protect the hip.

Read more about Avascular Necrosis of the Hip Joint here.

Do you have more questions?