.png)
Avascular necrosis (AVN)—also known as osteonecrosis—is a serious condition where the blood supply to the femoral head (the ball of the hip joint) is disrupted. Without proper blood flow, the bone tissue begins to die, leading to joint collapse, pain, and loss of hip function.
Early detection and intervention are critical to preserving joint health and avoiding long-term disability. In this post, we’ll cover what causes AVN of the hip, how it’s diagnosed, and the most effective treatment options.
What Is Avascular Necrosis (AVN)?
AVN occurs when blood flow to the femoral head is reduced or completely blocked. Without oxygen and nutrients, the bone weakens and eventually collapses. The surrounding cartilage may also deteriorate, causing the hip joint to lose its smooth motion.
➡️ Related: Understanding Hip Anatomy
Common Causes of AVN
Several conditions and risk factors can impair blood supply to the hip:
Trauma or injury – Fractures or dislocations can damage blood vessels.
Steroid use – High-dose corticosteroids are a leading non-traumatic cause.
Alcohol abuse – Chronic alcohol use interferes with blood flow and bone health.
Medical conditions – Lupus, sickle cell disease, and blood clotting disorders.
Idiopathic (unknown cause) – In many cases, no clear cause is identified.
Signs and Symptoms of AVN in the Hip
AVN may progress silently in its early stages. As it worsens, patients often report:
✅ Deep, throbbing pain in the groin, thigh, or buttock
✅ Increased pain with weight-bearing or activity
✅ Stiffness and decreased range of motion
✅ Limping or difficulty walking
✅ Pain at rest in advanced cases
If you're experiencing persistent hip pain, it’s important to explore all possible causes.
➡️ Learn more: Causes of Hip Pain
How Is AVN Diagnosed?
Diagnosis typically involves:
Physical examination – Checking for pain, range of motion, and gait changes
X-rays – Useful in later stages to detect bone collapse
MRI – The most sensitive tool for early detection of AVN
CT scans or bone scans – Occasionally used for detailed bone imaging
➡️ Learn more about how to read your hip x-rays
Treatment Options for Avascular Necrosis of the Hip
Treatment depends on the stage of AVN and how much the joint is damaged.
1. Non-Surgical Treatment (Early Stages)
Activity modification – Reducing weight-bearing activities
Assistive devices – Crutches or canes to relieve pressure
Medications – NSAIDs for pain; bisphosphonates for bone health
PRP or stem cell therapy – Investigational approaches to promote healing
➡️ Learn more about PRP injections for hip pain
2. Surgical Options (Advanced or Progressive AVN)
🦴 Core Decompression
Drilling into the bone to relieve pressure and stimulate blood flow
Often combined with bone grafting or stem cell therapy
🦿 Osteotomy
Reshapes the bone to shift weight away from the damaged area
🤖 Total Hip Replacement
Recommended for late-stage AVN with joint collapse and cartilage loss
Removes the damaged femoral head and replaces it with a prosthetic joint
➡️ See our guide to hip preservation vs. replacement
What Is the Prognosis for AVN?
Without treatment, AVN often progresses to joint destruction within 1–3 years. However, with early diagnosis and appropriate intervention, many patients can preserve their hip joint and avoid total hip replacement for years.
Can AVN Be Prevented?
While some causes of AVN can't be controlled, you can lower your risk by:
Limiting alcohol consumption
Using steroids only when necessary
Managing chronic medical conditions (e.g., lupus, clotting disorders)
Seeking prompt treatment for hip trauma
Key Takeaways
Avascular necrosis (AVN) is a condition caused by loss of blood flow to the femoral head.
Symptoms include groin pain, stiffness, and difficulty walking.
Early stages may be treated conservatively; advanced stages often require surgery.
Imaging—especially MRI—is key to early detection.
With early care, it’s possible to delay or avoid hip replacement.
