Joint Cracking...Fact & Fiction
"Cracking joints" are an interesting and poorly understood
phenomenon. There are many theories as to why joints crack
or pop, but the exact cause is simply not known.
Painless cracking of joints is as a rule not harmful.
However, common sense generally would suggest that the
intentional and repetitive cracking of one's joints not
only is potentially socially bothersome but also could be
physically troublesome when it produces pain.
Knuckle "cracking" has not been shown to be harmful or
beneficial. More specifically, knuckle cracking does not
cause arthritis.
Joint "cracking" can result from a negative pressure
pulling nitrogen gas temporarily into the joint, such as
when knuckles are "cracked." This is not
harmful. "Cracking" sounds can also be heard if tendons
snap over tissues because of minor adjustments in their
gliding paths. This can occur with aging as muscle mass and
action change.
If cracking is accompanied by pain, there could be
underlying abnormalities of the structures of the joint,
such as loose cartilage or injured ligaments. Some patients
with arthritis (inflammation of joints, usually painful),
bursitis, or tendinitis notice "cracking" sounds with joint
movements due to the snapping of irregular, swollen
tissues.
For more information from MedicineNet.com, please see our
Arthritis
Center.
Last Editorial Review: 7/6/2004