Can Avascular Necrosis (AVN) of the hip improve?

From the Guidelines

Avascular necrosis (AVN) of the hip typically does not improve on its own and tends to be progressive without treatment. The condition is characterized by bone death due to inadequate vascular supply, and its progression can lead to subchondral fracture and secondary osteoarthritis 1. According to the American College of Radiology, early diagnosis is crucial to exclude other causes of pain and to allow for possible early surgical prevention to prevent articular collapse and the need for joint replacements 1.

Key Considerations

• The necrotic volume of epiphyseal osteonecrosis has been shown to be predictive of future articular collapse, with femoral heads with necrotic volume >30% progressing to collapse in 46% to 83% of cases 1.
• Early-stage AVN may be managed with medications like bisphosphonates or anticoagulants, along with protected weight-bearing using crutches or a walker for 6-12 weeks to reduce pressure on the affected hip.
• Core decompression surgery may be beneficial in early stages (Ficat stages I-II) to reduce pressure and increase blood flow to the affected bone 1.
• For more advanced AVN, joint-preserving procedures like bone grafting or osteotomy might help, but many patients eventually require total hip replacement.

Treatment Outcomes

• Treatment outcomes depend heavily on the stage at diagnosis, with early intervention offering the best chance of preventing progression 1.
• Without treatment, most cases of hip AVN will continue to deteriorate, leading to collapse of the femoral head and severe arthritis.
• The underlying cause of AVN must also be addressed, such as stopping corticosteroids if possible or managing alcohol consumption 1.

Management Strategies

• Noninvasive therapy for osteonecrosis has so far gained limited supporting data, including statins, bisphosphonates, anticoagulants, extracorporeal shock wave therapy, and hyperbaric oxygen 1.
• Invasive therapies for early osteonecrosis aim at preventing articular collapse and delaying/preventing the need for joint replacement, such as core decompression supplemented with injection of autologous bone marrow cells, vascular fibular grafting, or electric stimulation 1.

From the Research

Improvement of Avascular Necrosis (AVN) of the Hip

• AVN of the hip is a condition that can cause significant musculoskeletal disability, but there are treatment options available that can improve symptoms and quality of life 2, 3, 4, 5, 6.
• Core decompression and bone grafting are surgical procedures that have been shown to be effective in relieving pain and improving hip function in patients with AVN of the femoral head 2, 6.
• Stem cell therapy is a newer treatment option that has been proposed for the treatment of early stage AVN of the femoral head, and has shown promising results in pre-clinical and clinical studies 4.
• Imaging procedures such as MRI and CT scans play a crucial role in diagnosing and staging AVN of the femoral head, and can help guide treatment decisions 5.
• The results of treatment for AVN of the hip can vary depending on the stage of the disease and the individual patient, but studies have shown that core decompression and other treatments can improve pain and function in patients with AVN of the femoral head 2, 3, 6.

Treatment Options

• Core decompression with tensor fascia lata muscle pedicle bone graft has been shown to be a effective treatment for AVN of the femoral head, with satisfactory outcomes reported in 83.07% of patients 2.
• Stem cell therapy has been shown to improve patient reported outcomes and reduce disease progression in clinical studies, but further research is needed to confirm its effectiveness 4.
• Hip preserving surgery and hip arthroplasty are also treatment options for AVN of the hip, but the choice of treatment depends on the stage of the disease and the individual patient's needs 3.

Outcomes

• Studies have reported significant improvements in pain and function in patients with AVN of the femoral head who undergo core decompression and other treatments 2, 6.
• The Harris hip score (HHS) is a commonly used outcome measure for evaluating the effectiveness of treatment for AVN of the hip, and has been used in several studies to report satisfactory outcomes in patients who undergo core decompression and other treatments 2.