Corticosteroids Use & Avascular Necrosis of the Femoral Head
Avascular necrosis (AVN) of the femoral head is a condition that involves the death of bone tissue due to a disruption in the blood supply. This condition is commonly caused by long-term corticosteroid use, which can lead to femoral head collapse, joint degeneration, and eventually arthritis. AVN often leads to the need for total hip replacement (THR) surgery, particularly in younger patients, as the femoral head becomes fragile and deformed over time. Understanding the pathophysiology, diagnosis, and management of AVN caused by corticosteroid use is crucial in preventing further joint damage and determining appropriate treatments.
MRI of the hip joints in the coronal section.
Functional Anatomy
The hip joint is a ball-and-socket joint, consisting of the femoral head (ball) and the acetabulum (socket) in the pelvis. The femoral head is supported by a vascular network that provides essential nutrients and oxygen to the bone. The articular cartilage on the femoral head and acetabulum allows for smooth, frictionless movement. In AVN, the blood supply to the femoral head is compromised, leading to bone death and collapse, which disrupts the joint’s function and causes pain. The labrum and ligaments surrounding the joint contribute to stability but are also impacted by the loss of bone integrity in AVN.
Biomechanics or Physiology
The femoral head relies on an intricate vascular supply to maintain its strength and structure. Disruption of this blood supply leads to bone necrosis, as the bone cells become deprived of necessary nutrients. Corticosteroids can cause an increase in lipid content in the blood, leading to blockages in small blood vessels (arterioles) around the femoral head. This lack of blood flow increases intramedullary pressure, resulting in bone cell death and collapse of the femoral head. Over time, this collapse causes joint instability, leading to pain and restricted movement.
Common Variants and Anomalies
AVN of the femoral head is commonly caused by long-term corticosteroid use, often in patients with conditions such as rheumatoid arthritis, systemic lupus erythematosus, or nephrotic syndrome. AVN is often bilateral in these patients, meaning both hips are usually affected. In contrast, AVN may occur unilaterally in patients with trauma or alcohol use. The disease progresses over time and can lead to femoral head collapse, causing severe arthritis and joint deformity. The condition is more prevalent in young and middle-aged adults (20-50 years old), especially those on high doses of corticosteroids.
Clinical Relevance
AVN of the hip is a progressive condition that can cause significant pain and loss of function. In young patients, AVN may be due to long-term corticosteroid use for the treatment of autoimmune diseases or organ transplantation. As the femoral head collapses, the hip joint becomes more unstable, and pain may worsen with activity. The loss of joint integrity leads to arthritis, muscle weakness, and a reduced range of motion. This often results in the need for hip replacement surgery when conservative treatments fail to relieve symptoms. Early diagnosis and intervention are crucial to prevent further joint deterioration and manage symptoms effectively.
Imaging Overview
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X-rays: Initial X-rays may show normal joint alignment, but as AVN progresses, subchondral sclerosis (hardening of the bone) and bone collapse may be visible.
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MRI: MRI is the preferred imaging modality to detect early signs of AVN, such as bone marrow edema (swelling) and loss of fat in the femoral head. In advanced stages, MRI will show subchondral fractures, femoral head collapse, and joint deformities.
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CT scans: CT scans provide detailed bone structure visualization, helping to assess the extent of femoral head collapse and joint damage.
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Bone scans: Bone scans can detect areas of increased metabolic activity, indicating early stages of AVN before bone collapse occurs on X-rays.
Associated Conditions
AVN of the femoral head is most commonly associated with:
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Corticosteroid use: High-dose or long-term steroid therapy is a major risk factor for AVN.
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Alcohol abuse: Excessive alcohol consumption can disrupt blood flow to the femoral head.
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Trauma: Hip fractures or dislocations can damage blood vessels, leading to AVN.
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Systemic diseases: Rheumatoid arthritis, lupus, and sickle cell disease are associated with AVN.
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Decompression sickness: Divers or individuals exposed to high-pressure environments may develop AVN due to nitrogen bubbles blocking blood vessels in the femoral head.
Surgical or Diagnostic Applications
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Diagnosis: The diagnosis of AVN is made through clinical evaluation and imaging studies (X-ray, MRI, CT). Blood tests and joint fluid aspiration may be used to rule out infection and confirm the presence of AVN.
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Surgical Treatment: Total hip replacement (THR) is the most common treatment for advanced AVN, especially in patients with femoral head collapse. For earlier stages of AVN, core decompression may be performed to relieve pressure and encourage revascularization of the femoral head. Stem cell therapy is being explored to promote bone regeneration in AVN patients.
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Non-surgical Treatment: Early-stage AVN may be managed with protected weight-bearing, pain medications, and physical therapy to improve hip function and delay surgery.
Prevention and Maintenance
While AVN is often unavoidable in patients requiring corticosteroid therapy, prevention strategies include:
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Minimizing corticosteroid use when possible and using the lowest effective dose.
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Regular monitoring of patients on long-term corticosteroid therapy for early signs of AVN.
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Maintaining bone health through calcium, vitamin D, and weight-bearing exercises to strengthen bones and improve circulation.
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Reducing alcohol consumption and avoiding excessive alcohol use to protect the vascular health of the femoral head.
Femoral Component in Primary Hip Replacement
Research Spotlight
A recent study on core decompression combined with stem cell therapy for early-stage AVN showed promising results, with a significant reduction in pain and improved hip function in patients. The study emphasized that while core decompression can delay the need for total hip replacement, combining it with stem cell injections enhances bone regeneration and improves long-term outcomes.
Summary and Key Takeaways
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Avascular necrosis (AVN) of the femoral head is a condition caused by disrupted blood flow, leading to bone death and collapse.
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Corticosteroid use is a major risk factor, especially in younger patients with autoimmune diseases or those undergoing organ transplantation.
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Early diagnosis with MRI is essential for detecting AVN before significant bone collapse occurs.
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Core decompression and stem cell therapy may delay the need for total hip replacement in early stages, while THR remains the gold standard for advanced AVN.
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Prevention includes reducing steroid use, maintaining bone health, and limiting alcohol consumption.
References / Citations (Optional)
“Study on stem cell therapy for avascular necrosis – see PubMed.”
Orthobullets, “Avascular Necrosis of the Hip: Causes and Management.”
Do you have more questions?
Are there any alternative treatment options for managing the underlying medical condition for which I require cortisone therapy, which may carry a lower risk of avascular necrosis?
Depending on the specific medical condition, there may be alternative treatment options available that carry a lower risk of avascular necrosis. These may include nonsteroidal anti-inflammatory drugs (NSAIDs), disease-modifying antirheumatic drugs (DMARDs), physical therapy, lifestyle modifications, or surgical interventions. It’s essential to discuss these options with your healthcare provider to determine the most appropriate course of treatment for your individual circumstances.
What should I do if I experience new or worsening joint symptoms while on cortisone therapy, and how quickly should I seek medical attention?
If you experience new or worsening joint symptoms such as pain, stiffness, or decreased range of motion while on cortisone therapy, it’s important to promptly inform your healthcare provider. Depending on the severity of symptoms, they may recommend further evaluation, adjustments to cortisone dosage, or additional treatments.
Are there any lifestyle modifications or precautions I should take if I’m on cortisone therapy to minimize my risk of developing avascular necrosis?
Yes, maintaining a healthy lifestyle is crucial. This includes regular weight-bearing exercise to promote bone health, a balanced diet rich in calcium and vitamin D, avoiding excessive alcohol consumption, and cessation of smoking. Additionally, patients should follow their healthcare provider’s recommendations for cortisone use closely.
Can avascular necrosis occur in patients who have been prescribed cortisone for short-term use, such as for acute conditions or injuries?
Avascular necrosis can occur even with short-term cortisone use, although it’s less common compared to long-term use. However, patients should be monitored for symptoms, especially if they have other risk factors such as pre-existing joint disease or previous cortisone use.
Is there a specific threshold or cumulative dose of cortisone beyond which the risk of developing avascular necrosis significantly increases?
While there is no precise threshold or cumulative dose established, higher doses and prolonged use of cortisone increase the risk of avascular necrosis. Individual susceptibility factors also play a significant role. Therefore, it’s essential to use cortisone judiciously, balancing its benefits with the potential risks.
How important is it for patients on cortisone therapy to undergo regular monitoring and screening for avascular necrosis, and at what intervals should these assessments be performed?
Regular monitoring and screening for avascular necrosis are essential for patients on cortisone therapy, particularly those at higher risk due to factors such as prolonged or high-dose cortisone use. Your healthcare provider can recommend an appropriate schedule for monitoring based on your individual risk factors and medical history.
Are there any alternative treatments or medications that can be used to manage avascular necrosis in patients who need to continue cortisone therapy?
While total hip replacement remains the gold standard treatment for advanced avascular necrosis, other conservative measures such as pain management, physical therapy, and lifestyle modifications may help alleviate symptoms and slow disease progression. Your healthcare provider can help develop a comprehensive treatment plan tailored to your individual needs and circumstances.
If avascular necrosis is diagnosed while on cortisone therapy, can discontinuing the cortisone treatment help slow or halt the progression of the condition?
Discontinuing or tapering cortisone therapy may be considered as part of the treatment plan for avascular necrosis, especially if the cortisone use is identified as a contributing factor. However, this decision should be made in consultation with your healthcare provider, taking into account the underlying medical condition and potential risks of stopping cortisone therapy abruptly.
Are there any additional precautions or monitoring measures I should take if I’m on long-term cortisone therapy to reduce my risk of avascular necrosis?
In addition to regular monitoring by your healthcare provider, it’s essential to maintain a healthy lifestyle, including regular exercise and a balanced diet, to support overall bone health. Your healthcare provider may also recommend bone density testing or other screening measures to assess your risk of developing avascular necrosis.
Can avascular necrosis progress rapidly once it starts, especially in patients on cortisone therapy?
Avascular necrosis can progress at varying rates depending on individual factors such as the underlying cause, severity of cortisone use, and overall health. In some cases, avascular necrosis may progress rapidly, particularly if not identified and managed early.
Are there any signs or symptoms that indicate I may be developing avascular necrosis while on cortisone therapy?
Symptoms such as persistent joint pain, stiffness, or difficulty bearing weight on the affected joint may indicate the development of avascular necrosis. It’s important to promptly report any new or worsening symptoms to your healthcare provider for evaluation.
Can avascular necrosis occur after receiving cortisone injections directly into the affected joint?
While less common than with systemic corticosteroid use, avascular necrosis can still occur as a complication of cortisone injections, especially when administered repeatedly or in high doses. It’s essential to discuss the potential risks and benefits of cortisone injections with your healthcare provider.
What are the potential complications or risks associated with total hip replacement surgery?
Potential complications of total hip replacement surgery include infection, blood clots, dislocation of the implant, implant wear or loosening over time, nerve injury, and leg length discrepancy. Your surgeon will discuss these risks with you in detail before the procedure.
Are there any support groups or resources available for people dealing with avascular necrosis?
Yes, there are support groups and resources available for individuals dealing with avascular necrosis. These may include online forums, local support groups, and educational materials provided by organizations such as the Arthritis Foundation and the National Osteonecrosis Foundation. Your healthcare provider can help you access these resources.
How successful is total hip replacement in relieving pain and restoring mobility for patients with avascular necrosis?
Total hip replacement is highly successful in relieving pain and restoring mobility for patients with avascular necrosis. The procedure involves replacing the damaged hip joint with an artificial implant, which can significantly improve quality of life for individuals with this condition.
If I develop avascular necrosis, what are the chances that I’ll need a total hip replacement?
The likelihood of needing a total hip replacement for avascular necrosis depends on factors such as the severity of the condition, the extent of joint damage, and your overall health. Your healthcare provider will evaluate these factors and discuss the most appropriate treatment options for you.
Are there any dietary changes or supplements that may help prevent avascular necrosis?
While there are no specific dietary changes or supplements proven to prevent avascular necrosis, maintaining a balanced diet rich in calcium and vitamin D can support overall bone health. However, it’s essential to consult with your healthcare provider before starting any new dietary supplements.
How often should I have imaging tests like X-rays or MRIs to monitor for avascular necrosis if I’m on long-term corticosteroid therapy?
The frequency of imaging tests such as X-rays or MRIs for monitoring avascular necrosis depends on various factors, including the duration of corticosteroid therapy and the presence of symptoms. Your healthcare provider will recommend the appropriate imaging schedule based on your individual circumstances.
Are there any warning signs or symptoms of avascular necrosis that I should watch out for?
Common warning signs and symptoms of avascular necrosis include joint pain, stiffness, limited range of motion, and difficulty walking. If you experience any of these symptoms, it’s important to consult with your healthcare provider for further evaluation.
What lifestyle changes can I make to reduce my risk of avascular necrosis if I need to continue taking corticosteroids?
Lifestyle changes that can help reduce the risk of avascular necrosis include maintaining a healthy weight, avoiding excessive alcohol consumption, avoiding smoking, and engaging in regular physical activity. It’s also important to follow your healthcare provider’s recommendations regarding corticosteroid use.
Can avascular necrosis occur in other joints besides the hip?
Yes, avascular necrosis can occur in other joints besides the hip, such as the knee, shoulder, and ankle. However, the hip is the most commonly affected joint, especially in cases related to corticosteroid use.
Are there any alternative medications or treatments that can be used to manage my condition without increasing the risk of avascular necrosis?
There are alternative medications and treatments available for managing various conditions without the risk of avascular necrosis. These options depend on the specific medical condition being treated and should be discussed with your healthcare provider.
How long does it typically take for avascular necrosis to develop after starting corticosteroid treatment?
Avascular necrosis (AVN) can develop within a few months to several years after starting corticosteroid treatment. The duration varies depending on factors such as the dosage and duration of corticosteroid use, as well as individual predisposing factors.
Dr. Suhirad Khokhar
My name is Dr. Suhirad Khokhar, and am an orthopaedic surgeon. I completed my MBBS (Bachelor of Medicine & Bachelor of Surgery) at Govt. Medical College, Patiala, India.
I specialize in musculoskeletal disorders and their management, and have personally approved of and written this content.
My profile page has all of my educational information, work experience, and all the pages on this site that I've contributed to.
