Recently I was asked to comment on popping your own joints (self mobilization). Is it good? Not so good? Harmful, even? First let’s look at what is believed to occur in a joint when you pop your joints.
The cavitation you hear when you pop your joints is believed to be a physical change in the the gases in the synovial fluid–from a liquid state rapidly to a gaseous state –based on the alteration of pressures in the confined space of your joint.
Science jargon aside, it is, more or less, the popping of an air bubble in your joint. This is believed to cause an neurogenic (originating from a nerve) response that causes muscle relaxation around the joint–like resetting a nerve in the joint, which can decrease muscle tone (tension).
So is it good or bad? Well, let’s look at what you are doing when you pop your joint. You are taking the smooth parts of the bone closed in a sealed capsule and moving them to an end range to the point that you change the pressures in the capsule. (Changes in volume create changes in pressure.)
Basically, the popping sound is not bad, but stretching the capsule to the end range can cause excessive wear and tear on a joint. Popping now and then: not bad. Popping the same joints frequently, however, can cause hypermobility in a joint, decreasing stability. Destabilizing a joint can lead to increased need for muscle tone to maintain structural support. This increased tone leads to a feeling of stiffness around the joint and a tendency to mobilize or pop the joint even further.
Ultimately, popping a joint might lead to an increased want to pop the joint to feel relief. This may cause increased capsule mobility, decreased stability, and eventually joint pain, as the joint feels unstable.
Physical therapists and chiropractors will perform joint mobilizations with purposes of achieving the same thing, namely muscle relaxation post mobilization. We understand that this is a quick fix for short-term relief. The true fix should be to help a patient not to feel the need to constantly mobilize.
Normally, for example, if I want to pop my neck, I would twist my neck to the end of its limits and then quickly move further past those limits to elicit a pop. I do the same thing when I twist my back as far as I can in a chair and then try twisting back the opposite direction without moving.
Next time you feel like popping a joint, perform an isometric muscle contraction instead–a contraction without movement. Instead of moving to the end range, try to contract the muscle surrounding the joint in a neutral position. Contract the muscle against resistance in an attempt to fatigue it and decrease the sense of stiffness and muscle tone (tension). There will be no cavitation, and therefore, no sound. The point is to avoid end range popping and simply experience muscle relaxation.