I frequently crack my fingers and my wrist cracks just moving them, they don't stop! I was once told this is a build up of carbon dioxide, not sure. But, I need to crack, I am a "crack" addict - Both hands from the elbow down are effected w/RSD and moving up my right arm now. Hey, my saying is if it helps, do it!
According to the encyclopedia:
"When a manipulation is performed, the force applied separates the articular surfaces of a fully encapsulated synovial joint, which in turn creates a reduction in pressure within the joint cavity. In this low pressure environment, some of the gases that are dissolved in the synovial fluid (which are naturally found in all bodily fluids) leave solution creating a bubble or cavity, which rapidly collapses upon itself, resulting in a 'clicking' sound. The contents of this gas bubble are thought to be mainly carbon dioxide.[1] The effects of this process will remain for a period of time known as the 'refractory period', which can range from a few minutes to some hours while it is slowly reabsorbed back into the synovial fluid. There is some evidence that ligament laxity may be associated with an increased tendency to cavitate.[2]"
Hang in there!