Posted on Jan 12, 2021 112
Who of us at least once in our lives has not crunched the joints, for example, on the fingers? For some, it has already become a habit, while others are afraid to repeat it - because there are rumors that after such actions you can get arthritis. Is this true?
Actually, no. If only because the joints do not take part in the “joint crunch”! The characteristic crackle is created by air bubbles bursting in the fluid.
We are talking about synovial fluid - this thick substance fills the cavities of the joints, acting as a lubricant. Synovial fluid has been found to contain large amounts of dissolved carbon dioxide. During sharp movement, gas bubbles form in the cavities between the joints - recall the physical process of cavitation - and it is the moment of formation of hundreds of such bubbles that is characterized by a specific crunching sound. Already 0.01 second after occurrence, most of the bubbles silently collapse. The rest continue to dissolve in the liquid for about 15 minutes: this explains why we cannot “crunch the joints” twice in a row in a short time.
Since no load on the joints is found in such actions, these actions can in no way lead to arthritis. This is proven not only by many medical studies conducted specifically to debunk this myth but also by the experience of Professor Donald Unger, who for 50 years every day crunched the joints in one hand, but never crunched the joints in the other. After 50 years, a study showed that crunching his joints every day had no effect on his health, and Donald Unger himself was awarded the Shnobel Prize for his research.
This is interesting: The Shnobel Prize was organized as a parody of the Nobel Prize and is awarded annually to the authors of the wittiest and most unusual research. For example, in 2017, the Shnobel Prize in Physics was awarded to Marc Antoine Fardin for proving that cats can be considered both solids and liquids because they take the shape of the vessel in which they lie. In doing so, the scientist said, adult cats spread faster than kittens. And in 2016, this prestigious prize went to scientists who proved that dragonflies land precisely on black tombstones.