Behind the Pop

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Behind the Pop

Question: What causes clicking and popping sensations in and around my joints, and is it a cause for concern?

The popping, clicking, and/or snapping noises (also known as crepitus) can come from air bubbles that are quickly released in the joint space. Composed of oxygen, nitrogen, and carbon dioxide, these gas cavities are typically found in synovial joints where there is a layer of fluid separating the two bones. Although the sounds may seem alarming, there is no need to worry. It can happen by accident with natural everyday movements or be performed deliberately (ex: popping knuckles).

Those who are hypermobile (those who can extend their joints outside of normal movement) may tend to experience more popping because their joints can be stretched further apart, thus allowing for more air cavities to form. You might notice that noisy joints run in the family, too! Similarly, those experiencing newfound mobility can also experience increased crepitus. This is not uncommon after starting physical therapy, so don’t feel worried if your once stiff neck is now making noises. Physical activity helps stimulate production of synovial fluid, which lubricates the joints. More movement = more air bubbles.

Side note: If you feel the need to crack your back or neck due to pain, it is best to consult with a physical therapist or chiropractor. If you try to perform your own self manipulations, you run the risk of pulling muscles, exacerbating hypermobility, stressing your ligaments, or misaligning your spine if you apply too much pressure.

Another potential reason for the sound may be due to rapid stretching of ligaments or tight tendons moving over bone. This may be particularly noticeable when transitioning from a seated to standing position, or when climbing stairs. It is painless and causes no damage to the body.

Production of scar tissue (which is a collection of cells and collagen that your body creates to repair damaged tissue) occurs with injury and/or surgery and is a normal part of the healing process. As you start introducing new movements or increase range of motion, scar tissue can produce a popping sensation when it separates or breaks apart. It may seem alarming at the time, but can result in decreased pain and improved mobility.

Crepitus may also occur with osteoarthritis (but not always). Osteoarthritis is known as the “wear and tear” type of arthritis. The smooth cartilage that provides cushioning between joints starts to deteriorate and may result in grinding or cracking noises. In severe cases, the bony surfaces may start rubbing on each other. These noises can occur with or without pain and can be accompanied with sensations of instability, weakness, and/or stiffness.

Popping sensations that result in pain, swelling, and decreased function are concerning. Potential examples of this type of popping include muscle, ligament, or tendon tears. These usually occur in the event of impact or trauma, in which they are stretched beyond their limit. This type of injury can be categorized as grade 1 (mild), grade 2 (moderate), and grade 3 tears (complete rupture). Even little microtears to muscles and tendons create an inflammatory response that can snowball into bigger issues (weakness, compensation, instability, loss of mobility, pain, re-injury) if not properly addressed. Inflammation around tendons/bursa, as well as torn cartilage/meniscus can also be culprits to noise.

Most forms of crepitus are completely normal and nothing to worry about, but if something doesn’t feel right or is impairing your level of function, the clinicians at Complete Physical Therapy are here to help and assess!