Orthopedics
Knee Osteoarthritis
Reviewed by the JordanMedHub Medical Editorial Team · 9/13/2026
Quick Answer
Knee osteoarthritis is the gradual wearing down of the cartilage that cushions the knee joint — the most common cause of chronic knee pain as people age.
In this article
Knee osteoarthritis is the most common form of arthritis affecting the knee, caused by the gradual breakdown of the cartilage that normally cushions the joint and allows smooth movement.
Symptoms
Pain that worsens with activity and improves with rest, stiffness (especially in the morning or after sitting for a while), swelling, a grating or crackling sensation with movement, and reduced range of motion are typical. Symptoms usually develop gradually over months to years, unlike the sudden onset of an injury. Sudden redness, warmth, fever, or an unusually severe or sudden flare are not typical of routine osteoarthritis and are worth a prompt medical evaluation, since they can instead point to a joint infection or an acute gout attack.
Risk Factors
Age is the biggest risk factor, but excess weight (which adds mechanical stress to the joint), previous knee injury, repetitive stress from certain occupations or sports, and genetics also play a significant role.
How It's Diagnosed
Diagnosis is typically based on symptoms, a physical exam, and an X-ray showing characteristic joint changes — there's no blood test that diagnoses osteoarthritis specifically.
Managing It
Our knee osteoarthritis treatment guide covers management options in depth, from weight management and physical therapy to medication and, for advanced cases, surgery.
Disclaimer
This guide is for general education only and does not diagnose any individual case.
Frequently Asked Questions
What causes knee osteoarthritis?
The gradual breakdown of cartilage cushioning the knee joint, most strongly linked to age, excess weight, previous injury, and genetics.
Written by JordanMedHub Medical Editorial Team
Updated 9/14/2026
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