Osteonecrosis of the Knee

Osteonecrosis (avascular necrosis) is loss of blood supply to bone, leading to bone collapse and joint pain.

This page covers causes, symptoms, diagnosis, treatment options, medications, surgical approaches, and recovery guidance related to osteonecrosis of the knee.

Quick Facts

Focus	Details
Condition Type	Degenerative
Common Symptoms	Pain that worsens with activity, Stiffness after rest or in the morning, Swelling or tenderness, Crepitus (grinding or clicking)
Typical Diagnosis	Medical history and physical exam, X-ray to assess joint space and bone changes, MRI to evaluate cartilage and soft tissues
Common Treatments	Activity modification and low-impact exercise, Physical therapy for strength and mobility, Weight management to reduce joint load, NSAIDs for pain and inflammation, Acetaminophen for pain relief

Causes and Risk Factors

Causes

Reduced blood flow to bone
Corticosteroid use or injury

Risk Factors

Increasing age
Excess body weight
Repetitive loading or high-impact activity
Family history of joint disease

Symptoms and Signs

Pain that worsens with activity
Stiffness after rest or in the morning
Swelling or tenderness
Crepitus (grinding or clicking)
Reduced range of motion

Diagnosis

Medical history and physical exam
X-ray to assess joint space and bone changes
MRI to evaluate cartilage and soft tissues

Treatment Overview

Focus	Details
Non-Surgical Care	Activity modification and low-impact exercise, Physical therapy for strength and mobility, Weight management to reduce joint load, Bracing or assistive devices
Medications	NSAIDs for pain and inflammation, Acetaminophen for pain relief, Topical anti-inflammatory medications
Injections	Corticosteroid injections for flares, Hyaluronic acid injections in selected cases
Surgical Options	Core decompression, Joint replacement in advanced cases

Self-Care and Recovery

Regular low-impact activity (walking, cycling, swimming)
Ice/heat for symptom relief
Supportive footwear

Possible Complications

Progressive pain and stiffness
Reduced mobility and function
Joint deformity over time

FAQs

What is Osteonecrosis of the Knee?

Osteonecrosis (avascular necrosis) is loss of blood supply to bone, leading to bone collapse and joint pain.

What symptoms are common?

Pain that worsens with activity, Stiffness after rest or in the morning, Swelling or tenderness, Crepitus (grinding or clicking), Reduced range of motion.

How is it diagnosed?

Medical history and physical exam, X-ray to assess joint space and bone changes, MRI to evaluate cartilage and soft tissues.

Activity modification and low-impact exercise, Physical therapy for strength and mobility, Weight management to reduce joint load, Bracing or assistive devices, NSAIDs for pain and inflammation, Acetaminophen for pain relief.

When should I seek care?

Seek care for severe pain, swelling, fever, or inability to bear weight, or if symptoms persist despite self-care.