Reasons Why My Knee Crackles When I Bend

Reasons Why My Knee Crackles When I Bend

You may hear an occasional pop or crackle when you bend or straighten your knees. The name of this noisy sensation is crepitus, and while it can feel alarming, it is usually harmless. However, if you start to notice crepitus after an injury or experience pain and swelling, you may need treatment from an orthopedist. Our team at New York Sports Medicine Institute would like to share some information about crepitus and how we can help! Continue reading to learn more! 

What is Crepitus?

A lot of your joints crack, and the knees are one of the most common joints that crack with certain movements. Usually, these noises and sensations are not a cause for concern unless they are associated with swelling or pain. The knee is the largest joint in your body. As you bend or straighten your knee, your kneecap (patella) glides back and forth inside a groove in your thighbone (trochlea). The soft tissues in your knee provide protection and padding. The cartilage in your knee enables the bones to glide smoothly against each other and keep it stable. The bones can grind and cause crepitus with abnormal wear in the cartilage. Some of the causes of crepitus include:

  • Air Bubbles – The noise associated with crepitus is usually a result of air seeping into the soft tissue and causing tiny bubbles in the synovial fluid. These air bubbles can burst with an audible cracking or popping sound as you bend or stretch your knees. While the noise can be alarming, it is usually harmless. 
  • Patellofemoral Pain Syndrome – When there is significant pressure between the femur and kneecap, the cartilage in this area can wear away. As the cartilage wears down, it can lead to patellofemoral pain syndrome (PFS). PFS can result from overuse or trauma or occur if a person’s knee is not aligned. Running, climbing stairs, and squatting can strain the area between the kneecap and femur. Crepitus may occur when climbing stairs or after sitting for a long time, and is usually combined with pain, puffiness, swelling, and stiffness. 
  • Age-Related Changes – As you age, your joints may become less lubricated. This can also cause the bones to rub together, resulting in crepitus. If the crepitus occurs with pain, it can signify osteoarthritis in your knee. 
  • Cartilage Tear – Crepitus can indicate torn cartilage, like a torn meniscus. The meniscus can tear during athletic activities when a person twists their knee but also occurs with age. 

Treatment for Crepitus 

Crepitus is often harmless and doesn’t require treatment. However, if you’re experiencing pain, swelling, or warmth in your joints, you should consult with our team at New York Sports Medicine Institute. There are several preventive measures you can take if your crepitus occurs when exercising. Some of these include avoiding inclines, keeping tension on pedals low when cycling, and using lighter weights when weightlifting. It’s essential to protect your knees to prevent long-term complications and pain. Targeted exercises can help to improve the range of motion in your joints and strengthen the muscles around them. This can help to reduce crepitus, reduce the risk of cartilage degeneration, and prevent pain. 

Contact Us

While most instances of crepitus are not a major cause for concern, it’s essential to protect your knee joints from damage. If you are experiencing swelling, pain, or redness in your knee, you should not ignore your symptoms. At New York Sports Medicine Institute, our team is here to help you manage your knee pain. We help patients dealing with a variety of conditions and will personalize your treatment program to suit your individual needs. To learn more about how we can help, be sure to contact us today! 



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