Does cracking your knuckles cause any damage? My daughter is driving me crazy!
Knuckles (and other joints) are surrounded by a lining called the synovial membrane. Inside it is synovial fluid, which acts as a lubricant and shock absorber so your bones don’t grind together. When you “crack” your knuckles, you expand the space between your bones, creating negative pressure that draws synovial fluid into the gap. The influx of fluid into the space causes the sound. If you crack your knuckles often, the synovial membrane loosens, making it increasingly easier for your joints to crack. There’s no bone damage done and no negative long-term effects. It’s just an icky sound.
Dina Kulik is a paediatrician and emergency room doctor in Toronto and mom to three boys, who are five, three and 17 months. Send her your kids’ health questions at firstname.lastname@example.org