Written by Dr. Jeffrey Peng, MD — Board-Certified Sports Medicine Physician Published: March 3, 2026 | Last Updated: March 3, 2026 Knee cracking, popping, and grinding are among the most common concerns I hear from patients in my sports medicine clinic. These sounds — collectively known as knee crepitus — can be alarming, especially when they seem to appear out of nowhere. The good news is that in most cases, noisy knees are completely harmless. However, understanding when c