Knuckle cracking and relationship with hand impairments

Can Your Knuckle Cracking Habit Cause Hand Impairments?

An interesting study 1 published in the journal of Orthopedics and Related Research, back in 2016, decided to see if knuckle cracking was related to hand impairments. The results showed a small increase in a range of motion among ‘cracked’ joints.

The Context Behind the Study

According to numerous records, the voluntary cracking of knuckles happens to be a common habit among humans. It has been reported to have a prevalence range of 25%-45%. Apparently, many people have a habit of cracking their knuckles when they’re typing on keyboards because their joints feel tight.

Numerous physicians have continued to be intrigued by such a habit. A previous large study did suggest their being an association between cracking knuckles and functional hand impairment. However, there’s also a counter-stance sharing that cracking knuckles doesn’t have any impact on a person’s hand-centric range of motion (ROM).

The current study decided to use imaging to find certain answers. The research team compared subjects with no history of knuckle cracking with subjects that did. They went over whether or not cracking joints improved range of motion and if Sonographic Evaluation was a reliable option for such observations.

The Methods Used

This study had 40 subjects with no history of joint problems in their hands. These subjects were aged 18 or older. A total of 30 subjects had a history of knuckle cracking, while 10 had no history of such a habit. Each subject had 10 digits, and that made for 400 MPJ (metatarsophalangeal) joints for evaluation.

Take note; there weren’t any differences in age, hand dominance, and gender distribution between the two groups. The subjects were asked to complete the standardized QuickDASH outcome measure questionnaire.

The research team did the clinical assessment for grip strength, swelling, grip, and ROM before as well as after performing the distraction maneuvers on the MPJs. A dedicated ultrasound unit was used for Sonography.

What Were the Results?

The results showed that on comparing subjects that had a history of habitual knuckle cracking with those who didn’t, the QuickDASH scores showed no differences.

The ROM comparisons between the two groups showed increased ROM in the knuckle-cracking subjects after ultrasound recorded manipulation. And swelling wasn’t observed at all in any of the subjects.

What Was Concluded?

The results of this study shared that yes, conflicting opinions do exist when it comes to knuckle cracking and the possible relationship with impairments. However, this study was unable to find any adverse effects of knuckle cracking habits in human hands.

The results did share that a person with such a habit does tend to have a higher likelihood of cracking other joints in their body. Maybe to help relax their posture?

Also, small increase in ROM was seen in joints that were cracked compared to ones that weren’t. But more research should be done to examine any possible long-term effects (both beneficial or adversarial) of the knuckle-cracking habit.