Why is crunchy knee sound?

A crunchy sound in the knee, often referred to as crepitus, can occur due to the movement of tendons and ligaments over bony structures. It may also result from the presence of air bubbles in the synovial fluid or the roughening of cartilage surfaces due to wear and tear. While it’s usually harmless, persistent or painful sounds could indicate underlying issues like Arthritis or cartilage damage and should be evaluated by a healthcare professional.