Avascular necrosis, also known as osteonecrosis or bone infarction, is a condition where the blood supply to the bone tissue is disrupted, causing the bone to die. It commonly affects the hip joint but can also occur in other joints such as the knee, shoulder, and ankle. The progression of avascular necrosis is classified into several stages, and understanding these stages is crucial in determining the appropriate treatment options.

The stages of avascular necrosis can be divided into four main categories: pre-collapse, early collapse, late collapse, and arthritis.

● Pre-collapse Stage: This stage is characterized by minimal to no symptoms, and the bone damage can only be detected through imaging tests such as an MRI or X-ray. During this stage, the bone tissue is still alive, but the blood supply to the bone has been disrupted, causing bone cells to die off. In the early stages, treatment may focus on preserving the bone tissue and preventing further damage. This can include rest, limiting weight-bearing activities, and medications to reduce pain and inflammation.

● Early Collapse Stage: As the condition progresses to the early collapse stage, the symptoms become more pronounced, and the bone tissue begins to break down. This stage is characterized by the onset of pain in the affected joint, which can range from mild to severe. As the bone tissue continues to break down, the bone may begin to collapse, causing further damage to the joint. In more advanced stages, surgical intervention may be necessary. This can include procedures such as core decompression, where a hole is drilled into the bone to relieve pressure and allow for new blood vessels to form. Another option is bone grafting, where healthy bone tissue is transplanted to the affected area to promote new bone growth.

● Late Collapse Stage: The late collapse stage is the most advanced stage of avascular necrosis, where the bone has completely collapsed, and the joint is severely damaged. Symptoms during this stage may include severe pain, limited range of motion, and difficulty walking or standing. At this point, the damage to the joint is irreversible, and the only treatment options are pain management and joint replacement surgery.

● Arthritis Stage: The final stage of avascular necrosis is arthritis, where the joint is no longer able to function correctly, and the bones begin to rub against each other, causing further damage. At this point, joint replacement surgery is the only option to relieve pain and restore mobility.

The following are the most common symptoms of avascular necrosis. However, each person’s experience may differ.

● One of the most common symptoms of avascular necrosis is pain in the affected joint, which may be severe and worsen over time. This pain may be felt during physical activity or even at rest and can significantly impact a person's quality of life.

● Another common symptom of avascular necrosis is stiffness and limited range of motion in the affected joint. This may make it difficult to perform regular tasks and activities, contributing to muscle weakness and atrophy.

● As the condition progresses, additional symptoms may develop, including bone collapse, joint deformity, and arthritis. In severe cases, avascular necrosis can lead to the need for joint replacement surgery or other invasive treatments.

The symptoms of avascular necrosis may look like other medical conditions or bone problems. Consult an Orthopaedic for a thorough diagnosis.

Current surgical interventions

❖ Core Depression: The procedure may use vascularised bone grafts or biological agents that promote bone repair. Core decompression is safe and effective in the early stages of osteonecrosis. Its use, combined with using autologous bone or bone marrow, can increase its success rate.

❖ Rotational osteotomy: It can be indicated when the lesion can be diverted away from the weight-bearing surface. Medical diseases can be rotated through intertrochanteric varus osteotomy, while anterolateral disease can be rotated via intertrochanteric valgus and flexion-producing osteotomy. Rotational osteotomy has a success rate of up to 90%; however, it can make future total hip arthroplasty more challenging.

In conclusion, Avascular necrosis is a condition that can significantly impact a person's quality of life, and understanding the stages of the condition is crucial in determining the appropriate treatment options. Early detection and treatment can prevent further damage and improve outcomes. It is essential to seek immediate medical attention if experiencing any of the common symptoms, including pain, stiffness, and limited range of motion in the affected joint.

Regrow® Biosciences is exploring the potential of mesenchymal stem cells (MSCs) as a potential therapy for avascular necrosis. MSCs are a type of adult stem cell that can differentiate into various types of cells, including bone, cartilage, and fat cells. MSCs also have anti-inflammatory properties that may help reduce the inflammation associated with avascular necrosis.

FAQ’s:-

Q: What are the common symptoms of avascular necrosis?

A: Common symptoms of avascular necrosis include pain, stiffness, and limited range of motion in the affected joint.

Q: What causes avascular necrosis?

A: Avascular necrosis is caused by a disruption of the blood supply to the bone tissue, which causes the bone to die.

Q: Is avascular necrosis a progressive condition?

A: Yes, avascular necrosis is a progressive condition that can lead to joint collapse if left untreated.

Q: How is avascular necrosis diagnosed?

A: Avascular necrosis is typically diagnosed through imaging tests such as an MRI or X-ray.

Q: What are the treatment options for avascular necrosis?

A: Treatment options for avascular necrosis vary depending on the stage of the condition and can include rest, medications, surgical intervention, and joint replacement surgery.

Q: Can avascular necrosis be cured?

A: While there is no cure for avascular necrosis, early detection and treatment can prevent further damage and improve outcomes.

Q: What happens if avascular necrosis is left untreated?

A: If left untreated, avascular necrosis can cause permanent damage to the bone and joint, leading to joint collapse and significant impact on a person's quality of life.

Q: Is avascular necrosis common?

A: Avascular necrosis is relatively uncommon, affecting approximately 10,000 to 20,000 people in the United States each year.

Q: Can avascular necrosis affect any bone in the body?

A: Yes, avascular necrosis can affect any bone in the body, but it most commonly occurs in the hip joint.

Q: Who is at risk for avascular necrosis?

A: Anyone can develop avascular necrosis, but certain factors can increase the risk, including steroid use, excessive alcohol consumption, and trauma to the bone or joint. Additionally, certain medical conditions such as sickle cell anaemia and lupus can also increase the risk.