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"Why are my knuckles cracking so much?"

ZocdocAnswersWhy are my knuckles cracking so much?


Recently my knuckles started cracking a lot. It is when I move them or bend my hands and things like that. I don't crack them myself and this has never been an issue before. Why are my knuckles cracking so much?


Cracking of your knuckles is caused by a phenomenon called cavitation. This is where the movement of a joint within its articulation causes small cavities of a vacuum in the joint fluid (called the synovial fluid) then rapidly collapse producing a sharp sound. It is the same source of sound that a whip produces when it snaps, or when a fighter plane flies by at super sonic speeds. No one really know why some people's joints crack and others don't. To be honest, studies on joint cracking are not that prevalent because it is not a significant clinical issues. We used to think cracking knuckles was associated with arthritis. This theory has been disproven. If you are having pain, swelling, or any other abnormality that is affecting your function, you should consider presenting the issue to your doctor. You could start with scheduling an appointment to see your primary care physician. A simple joint examination can reveal whether you have any evidence of joint problems such as arthritis. If you do, then you may need a workup for why you are having this problem such as blood work to look for evidence of rheumatoid disease, or even referral to a rheumatologist. Good luck.

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