Cracking your knuckles does not hurtyour bones, sound you hear is just gas bubbles bursting.

If you’ve ever bind your fingers together and
bent your fingers back, you know what knuckle
popping sounds like. Joint produce that CRACK
when bubbles burst in the fluid surrounding the joint.
Joints are the meeting points of two separate bones,
held together and in place by connective tissues and
ligaments. All of the joints in our bodies are
surrounded by synovial fluid, a thick, clear liquid.
When you stretch your ligaments by pulling the bones apart to
crack your knuckles a gas in the synovial fluid
escapes and turns into a bubble. This process is
called cavitation. Cavitation ends when the
bubble eventually bursts, producing that popping
sound. After that, your joints won’t be able to crack
because
It takes about 25 to 30 minutes for the gas to
redissolve into the joint fluid.
Cracking your knuckles can have therapeutic benefits.
it stimulates your tendons, relaxes
your muscles, and loosens your joints.
but scientists have discovered that it
can cause tissue damage in the joints.
Knuckle-cracking pulls your finger bones apart
which stretches your ligaments. Too much
stretching of your ligaments will cause
damage to your fingers and also result in reduced grip strength.