How To Pop Your Knee Without Injuring Yourself?


It is common to have popping or cracking noises coming from the knee, especially once you cross the age of 40. These popping or cracking noises are known as crepitus, or sometimes crepitation. (1,2,3) Crepitus is a term used to describe any type of creaking, grinding, grating, popping, crunching, or cracking noise that comes when you move any joint. While anyone can experience this phenomenon at any age, it tends to become more common as one gets older. (4,5) Crepitus in the knee is usually harmless, but sometimes it may indicate that there is another underlying health condition or it might be developing. If you feel a strange sensation in the knee joint, for example it may feel like it is inflated with air or has gotten locked into place, then you may have an overwhelming urge to pop the knee back into place. Popping your knee back into place has to be done safely, and you need to move carefully, slowly, and with intention. (6,7)

How Can You Pop Your Knee Joint?

The knee joint is designed in a complicated manner. There are many layers of cartilage that cushion the part between the fibula (shin) bones to the femur or thigh bone and the tibia. The knee joint is further covered with another bone known as the patella or the kneecap. It is essential to understand that if you feel any kind of pain while trying to crack or pop your knee, you need to stop immediately. (8,9)

Here are the steps to stretch to pop your knee:

  1. The first step is to sit down and take the pressure off the knee as soon as possible.
  2. Now extend the leg straight in front of you and then point your toe upwards.
  3. Now, raise your leg as high as you can and bend your knee in and out. This should be towards the rest of the body. Keep doing this until you hear a pop.

However, there are some precautions that need to be considered.

There are two main types of knee pops. These include:

  • Physiological knee pops that are loud enough for everyone to hear.
  • Pathological knee pops that are only heard and felt by the person themselves.

Knee cracking that is physiological in nature and is also frequent could be a sign that you need to undergo physical therapy or further diagnostic testing to find out what is the underlying issue with the knee joint that it is causing crepitus.

Why Do You Feel Like Popping Your Knee?

All the joints in the body are coated with a lubricant known as the synovial fluid. (10) The synovial fluid contains nitrogen and oxygen, along with other elements as well. Sometimes, the gases present in the synovial fluid can start to build up, and they need to be released. This is what causes a crack in the knees. However, the exact causes of crepitus can vary and are not necessarily straightforward. In fact, researchers are working towards learning more about what are the causes of these cracking and popping sounds in the joints.

It is also believed that bones that break and fail to heal properly and tendons that get caught on the ridges of the bones and muscles as you move are also some of the other causes of knee popping or cracking.

As you age, the cartilage in the knees starts getting worn. This eventual deterioration of the knee joint can make it feel ‘creaky’ since the bone begins to rub on bone whenever you move your knees. (11)

Sometimes, though, pain in the knee joint can also be a red flag that may be an indication of an underlying knee injury or other developing health conditions. These include:

  • Osteoarthritis of the knee (12)
  • Torn or strained meniscus (13)
  • ACL injury (14)
  • Plica syndrome (15)
  • Iliotibial band syndrome (16)
  • Bursitis, which is the inflammation of the bursa located inside the knee joint (17)

Do You Need To See A Doctor For The Popping Of The Knee?

If you have injured your knee and feel a popping sound from your knee during the injury, there is a chance that a bone has fractured or a tendon has cracked. You should consider going to a doctor to find out if you require further testing.

You should definitely consult a doctor for your injured knee if you notice any of the following:

  • Fever after injury or exercising
  • Swelling or redness around the kneecap that seems to appear occasionally
  • Consistent pain while jogging or walking
  • Pain or tenderness when you touch the knee

Here are some of the more serious symptoms that warrant a visit to the emergency room:

  • Intense pain
  • Knee cracking or popping at the time of the injury
  • Inability to bend the knee
  • Swelling that appears without any apparent cause or warning


Popping your knee is a relatively safe thing to do if there is no injury or pain accompanying the sound. It is a good idea to practice joint-loosening exercises like yoga and Pilates that help make your joints become more flexible. You can also ask your doctor or a physical therapist for more recommendations.

It is never recommended that you try to crack a joint that is already giving you pain. You need to be also aware of the fact that regular popping or cracking from the knee joint could very well be a sign of an injury, or it can also indicate that there is another developing health condition that needs your attention, like osteoarthritis.


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