Knee osteoarthritis is a degenerative joint condition caused by progressive loss of articular cartilage.
It commonly affects middle-aged and elderly individuals, but may appear earlier after injury or obesity.
Pain worsens with activity such as walking, climbing stairs, or squatting, and improves with rest.
Morning stiffness is brief, usually lasting less than 30 minutes.
Crepitus (grating sensation) may be felt during knee movement due to irregular joint surfaces.
