Can Cracking Knuckles Lead To Arthritis?
Knuckle cracking: it’s a habit that is satisfying to some and annoying to others. But can it lead to the development of arthritis?
We all recognize the sudden loud popping sound of knuckles being cracked. It is estimated that between 25 and 54 percent of us habitually crack our joints, and we know that most knuckle crackers are men. If this habit is yours, family members or friends may have tried to discourage the practice with warnings that cracking knuckles now can lead to joint problems like arthritis later. But is there any truth in these predictions of medical harm?
According to researchers, at least when it comes to arthritis, the answer is no. A number of studies compared rates of hand arthritis between people with knuckle-cracking habits and people who don’t crack their knuckles, and found no correlation between knuckle cracking and arthritis.
Joints are formed where the ends of two bones meet. The bone surfaces at this point of connection are covered with cartilage and surrounded by a capsule that is filled with synovial fluid. This fluid lubricates the joint, cushions the cartilage and tissue, and provides nutrients to the cells that maintain joint cartilage. Synovial fluid contains dissolved gases including oxygen, nitrogen, and carbon dioxide.
When you pull apart the bones of a joint by stretching your fingers or bending them backwards, you create negative pressure in the joint. As the pressure of the synovial fluid drops, gases dissolved in the fluid become less soluble and unstable bubbles form and burst with a popping sound. It takes about 30 minutes for the gas to redissolve and be absorbed back into the synovial joint fluid. Once the gas is redissolved, knuckles can be popped again. Cracking sounds can also be triggered by tendons snapping over a joint.
Although there is no connection between knuckle cracking and the development of arthritis, studies do suggest that habitual knuckle cracking may be related to hand swelling, damage to the soft tissues around the joint, and some loss of grip strength. On the positive side, there is also evidence of increased joint mobility right after joints are cracked.
Generally, whether you crack your joints out of habit or hear an occasional spontaneous popping in a joint, these sounds are normal and there’s no reason for concern. However, if you feel pain with the popping, or if the joint becomes stuck, swollen, or uncomfortable to move, it’s time to seek medical advice. Pain, swelling, and loss of joint mobility may signal joint damage.
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