Clicking Joints

Does cracking your knuckles cause arthritis?

Surveys show a large percentage of arthritis sufferers attribute their condition, at least in part, to a lifetime of popping their joints. But here's what's really going on: the "pop" of a cracked knuckle is caused by synovial fluid, the thick lubricant that surrounds every joint. When you stretch or pull your fingers backward, the bones of the joint pull apart, creating a low-pressure environment that creates a bubble which implodes, or collapses in on itself, sending synovial fluid crashing inward.

That noise you hear when the bubble implodes is not as bad as it sounds, and there are studies that confirm this. One of the largest was published in the Annals of the Rheumatic Diseases and looked at 300 healthy people over 45-years-old, about a quarter of them habitual knuckle crackers.

The rates of arthritis of the hand were similar in both groups, though the knuckle crackers, on average, had reduced grip strength along with higher rates of swelling of the hand.