“Crunching sound in the knee is referred to by physicians as crepitus,” says Devin B. Peck, MD, owner of Austin Interventional Pain in Austin, TX.

What causes a crunching sound in the knees?

Dr. Peck explains, “It is typically caused by the rubbing of cartilage on the joint surface or other soft tissues around the knee during joint movement.

“When crepitus is painful, it may represent the sliding of an irregular, damaged or degenerated ligament.

“It can also indicate damage or irregularity in one of the menisci (plural of meniscus), the pads of cartilage which cushion the inner and outer aspects of the knee joint.”

If the crunching sound in your knee or both of them is not accompanied by any discomfort, there is no reason to be concerned. Dr. Peck says, “Benign, painless crepitus is common and requires no treatment.

“However, painful crepitus can indicate degenerative arthritis, inflammatory arthritis (like rheumatoid arthritis) or an injury to one of the ligaments or menisci.”


“Treatment will depend on the cause, but may include physical therapy, anti-inflammatory medications, injections or surgery.”

Which means, if you’re seeking solutions to a crunching noise in one or both knees that is also accompanied by pain or even a feeling of instability, it’s time to see a doctor to find out exactly what is wrong.

Dr. Peck’s areas of interest include chronic and acute musculoskeletal pain, sports injuries, arthritis and cancer pain, among many others. Austin Interventional Pain was established in 2019.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.  


Top image: Shutterstock/thebigland