Why does an individual with advanced osteoarthritis in their knee experience increased pain during activities requiring repetitive knee flexion, such as stair climbing or squatting?

💡 Explanation

Osteoarthritis involves cartilage degradation, therefore repetitive knee flexion increases bone-on-bone contact because the reduced joint space from cartilage loss leads to heightened stress concentration and pain. This occurs via biomechanics altering normal loading, rather than enhanced cushioning or reduced friction.

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