What is the management of avascular necrosis of the femoral head?

From the Guidelines

The management of avascular necrosis of the femoral head should prioritize early diagnosis and intervention to prevent articular collapse, with core decompression and pharmacological interventions like bisphosphonates being considered for early-stage disease, and total hip arthroplasty for advanced cases with significant joint destruction. The approach to managing avascular necrosis (AVN) of the femoral head is multifaceted, depending on the stage of the disease and patient-specific factors 1. For early-stage AVN, before the collapse of the femoral head, the focus is on preventing further bone death and collapse. This can involve protected weight-bearing, pain management with NSAIDs, and possibly the use of bisphosphonates to slow bone resorption or statins to potentially enhance osteoblast function, as suggested by recent guidelines 1.

Key Considerations

• Early diagnosis is crucial to initiate appropriate management and prevent progression to more severe stages of the disease.
• The necrotic volume of the femoral head is a significant predictor of future articular collapse, with volumes greater than 30% associated with a higher risk of collapse 1.
• Patient factors such as age, body mass index, and the presence of joint effusion or bone marrow edema also influence the risk of collapse and should be considered in management decisions.

Management Options

• Core decompression is a surgical procedure that may be considered for early-stage AVN to reduce intraosseous pressure and potentially improve blood flow to the affected area 1.
• Bone grafting procedures can provide structural support and may be used in conjunction with core decompression.
• For later stages of the disease, especially with femoral head collapse, joint-preserving procedures like osteotomy or free vascularized fibular grafting may be options in selected patients, particularly younger individuals 1.
• Total hip arthroplasty remains the definitive treatment for advanced AVN with significant joint destruction, offering reliable pain relief and functional improvement 1. Given the complexity and variability in disease presentation, management should be individualized, taking into account the latest evidence and guidelines, such as those outlined in the ACR Appropriateness Criteria for osteonecrosis 1.

From the Research

Management of Avascular Necrosis of the Femoral Head

The management of avascular necrosis of the femoral head involves various treatment options, including:

• Core decompression with bone grafting, considered the gold standard for early stages 2
• Extracorporeal shockwave therapy (ESWT), which has shown beneficial effects in improving pain and function of the hip and regression of the ONFH lesion 2
• Bisphosphonate therapy, such as alendronate, which has been shown to prevent disease progression, bone collapse, and the requirement for surgery in avascular necrosis of the femoral head 3, 4, 5
• Combination therapy, including oral alendronate and intravenous zolendronic acid, which provides a pragmatic solution for non-femoral avascular necrosis 3

Treatment Goals

The aims of treatment are to:

• Maintain the range of movement of the hip
• Prevent collapse of the femoral head
• Postpone the need for arthroplasty in young and active patients 6, 5

Treatment Outcomes

Studies have reported the following outcomes:

• Improvement in clinical function and reduction in the rate of collapse with alendronate treatment 4
• Delay in the need for total hip replacement with alendronate treatment, even in Ficat stage-III hips 4
• Marked reduction in rates of clinical failure, radiologic progression, and collapse of femoral head with 3-year-long oral alendronate therapy, with benefits lasting up to 10 years 5