We all have heard our joints crack. Sometimes we’ve been even frightened that we might have moved something out of place when it happened. Other times we do it on purpose as it gives us great relief. There has been a long-term fallacy that cracking joints will lead to arthritis in the future. That theory, on a number of occasions, has been disproved. Cracking joints, also known as joint cavitations, is a normal process by where you rapidly lengthen and suddenly shorten the joint tissue producing the loud audible “crack” sound. This does not mean that the joints are out of place or alignment. As the joint lengthens, the space between the two bony structures increases, which reduces the pressure inside of the joint. As the pressure rapidly drops, carbon dioxide comes out of solution (think of bubbles in the coke bottle when you open it) forming bubbles and ultimately causing the cracking sound. It takes 20-30min for the carbon dioxide to be absorbed by the joints after such process. This is the main reason why you can’t crack the same joint twice.
Joint manipulation (cracking of joints) is one of the techniques that chiropractors, osteopaths and physiotherapists use to reduce pain and improve joint range of movement. While it works well in short term, it has no benefit for long-term recovery and healing processes, especially in the spine.
R. Bordeur. 1995. The audible release associated with joint manipulation. Journal of Manipulative and Physiological Therapeutics, 18(3), 155-164.
Rubinstein, S.M, et al. 2012. Spinal manipulative therapy for acute low-back pain. Cochrane Library Reviews, http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD008880.pub2/full
Rubinstein, S.M., et al. 2011. Spinal manipulative therapy for chronic low-back pain. Cochrane Library Reviews, http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD008112.pub2/full