Knuckle Cracking

Knuckle cracking is an asocial habit usually seen in students while studying or while watching television. It can cause a risk of functional hand impairment due to the swelling of the fingers, dislocation of the tendons or damage of soft tissues. There may be lowering of the fingers griping strength and excessive cracking may damage the surrounding ligaments. Though these effects are labeled minor damages and can be reversible after omitting the habit, but it would worsen any joints disease like arthritis in elderly people.

There are different theories, still unanswered by the medical science, about the sounds produced due to cracking of the knuckles. According to one theory, sounds are due to the snapping of the ligaments or tendons over the bony prominences or due to the synovial fluid in the knuckle joints.

But the second theory suggests that when the joint becomes deformed while cracking, there is a decrease in the pressure of gases between the joint spaces. It is the rushes of gases from the surrounding area towards the lower pressure area in the joint space, which produce crackling sounds. This theory strongly supports the concept of the gap between two crackling sounds, as the gases takes almost about 15 – 20 minutes to readjust in the joint spaces.

With the justification of the first theory, we can answer the concept of micro trauma in the tissues of the fingers. There are little or few evidences to proof any association of arthritis with the habit of knuckle cracking but it will lead towards tendonitis. Bursitis also worsens due to excessive knuckle cracking. Dysfunction of the hands due to this habit can be treatable, but if arthritis is also present in association, palliative care is the only choice. Usually the knuckle crackers do crack their fingers as long as they feel any pain or damage in the fingers.