Knuckle cracking can be an unconscious but pleasurable habit. Or, it can be a grating and annoying noise. It all depends on who is doing the cracking and who is doing the listening. For years, there has been speculation on what causes the knuckles to make their characteristic cracking sound. Now, a new study has the answer.
Dr. Boutin oversaw researchers who recorded simultaneous audio and visual evidence of knuckles cracking. Forty healthy adults, including 17 women and 23 men (age range 18 to 63), participated in the study. The participants included 30 individuals with a history of habitual knuckle cracking and ten without. They were examined at UC Davis with ultrasound imaging, as they attempted to crack the knuckle at the base of each finger, known in medical language as the metacarpophalangeal joint (MPJ).
The authors of one 2015 study concluded that the cracking or popping sound results from the formation of cavities. They came to this conclusion after looking at what happens when joints crack on MRI scans.
A popping sound in a joint such as the elbow may result from instability or looseness, the American Association of Orthopedic Surgeons points out. A person might also find that the joint catches as they move.
If the sound of a joint cracking occurs with any pain, this may indicate damage to the joint and possibly a tear in the cartilage that cushions it. Anyone experiencing this should consider contacting a healthcare professional.
One physician researched his own knuckle cracking, in response to complaints from his family. He cracked the knuckles of his left hand at least twice a day for 50 years, but not those of his right hand.
Dr. Fackler explains that the pressure applied to knuckles \"causes vapor pockets\" within the fluid inside the joints. This then \"creates a vacuum that sucks the joint apart rapidly,\" causing a popping sound in the knuckles.
So why do so many people find relief in cracking their knuckles Cracking your knuckles \"feels as if it relieves tension in the joints,\" Dr. Fackler says. \"When that phenomenon happens, it causes a distraction of the joint and separates the joint for a brief second. If traction is applied to the joint, it feels as if it loosens up and is more mobile.\"
So, as it turns out, you can crack your knuckles, limitlessly, without the consequences of arthritis. Just don't be too caught off guard if your rings fit a little tighter after a knuckle-cracking session. Cracking knuckles can cause temporary swelling or a subtle increase in the size of your hands, but is ultimately harmless. \"There are no long-term studies that show knuckle-cracking causes any damage,\" Dr. Fackler says. Until then, \"When it comes to your fingers, don't even worry about it.\"
Whether you do it for a sense of relief or as a nervous habit, many of us are familiar with the popping sound and sensation that happens when we crack our knuckles. While this habit may be a satisfying experience, cracking your knuckles too often may lead to issues affecting your hand health.
Your metacarpophalangeal joints are the knuckles, where your fingers meet the rest of your hand. Although these joints are very stable, it is still possible to dislocate these joints when enough external pressure is applied. Typically, this affects the index and pinky fingers.
So is there long-term damage if we do it daily According to some physicians and countless studies, no. There is absolutely no evidence that cracking your knuckles is bad for you or causes arthritis over time.
Unfortunately, for you knuckle-crackers there seem to be no benefits, either. Well, other than the satisfaction of the bone-snapping sound and the fun sound effects. Oh, and maybe proving your mother wrong.
Scientists have used ultrasound machines to figure out exactly what's going on in our joints when we crack them, putting an end to a decades-old debate about where that distinctive cracking sound comes from.
Back in April 2015, researchers from the University of Alberta published a paper based on MRI imaging of finger joints being cracked saying that the popping sound is caused by the formation of air bubbles that form in the fluid that surrounds our joints - called synovial fluid.
Led by radiologist Robert D. Boutin from the University of California, Davis, the team recruited 40 healthy participants, 30 of whom were regular joint-crackers, and 10 who were not. Of those who were habitual crackers, the older ones admitted to cracking their knuckles up to 20 times a day for the past 40 years.
The researchers suspect that the cracking and visual flash in the ultrasound images is related to changes in pressure that occur in the synovial fluid, as Boudin explained to Richard Hartley-Parkinson at the Metro:
\"There have been several theories over the years and a fair amount of controversy about what's happening in the joint when it cracks. We're confident that the cracking sound and bright flash on ultrasound are related to the dynamic changes in pressure associated with a gas bubble in the joint.\"
In April 2015, the University of Alberta team backed up the original bubble-forming hypothesis with their MRI recordings, but they still hadn't come up with any conclusive proof. So which is it, does the sound result from a bubble popping in the joint or from a bubble being created in the joint
Perhaps you have heard that cracking your fingers (or knuckles) can lead to arthritis, or that your fingers will become permanently disfigured. Maybe you were told as a child that cracking your fingers would stunt their growth.
So when you hear someone cracking their fingers or knuckles, you may admonish the person for doing irreparable damage to their joints. But is cracking your fingers and other joints really all that bad The answer may surprise you.
When you crack your fingers, you are stretching (or flexing) the joint past its degree of usual rotation, but not past its anatomic barrier. In other words, you need something else to push it to that point, such as using your other hand to pull back the fingers or to squeeze the knuckles.
Researchers have reported that the cracking sound is due to a sudden release of gaseous bubbles from fluid in the joint. This mixture of gas and liquid is thought to be what causes the feeling of pressure in the first place.
When cracking your fingers, toes, shoulders, elbows, back, or neck, the sense of relief is achieved when that tension is released. The joint feels relaxed again, which helps to alleviate stress in the body.
There is actually no evidence that cracking your fingers is harmful or can cause damage. On the contrary, some researchers have discovered a lower incidence of arthritis in people who do crack their fingers.
Cracking your fingers may bring relief, but if you are suffering from chronic pain in your fingers, wrists, elbow, or shoulder, you should consider seeing a specialist. A hand surgeon is the best person to see when it comes to diagnosing and treating conditions affecting those areas.
According to Harvard Health Publishing, the sound of cracking joints is probably caused due to gas bubbles in your joints bursting. Some research suggests that it is caused due to popping bubbles in the synovial fluid - a fluid that keeps your joints lubricated.
Inflammation around tendons (fibres that connect your muscles to your bones) can also result in cracking or popping sounds. Conditions like tendonitis or tennis elbow can be accompanied by popping sounds.
Usually, painless joint cracking or popping poses no concern or threat. It arises from muscles or tendons moving over each other, popping the nitrogen bubbles that are normally formed between the spaces in our joints.
Sometimes, the noise may also be associated with worn cartilage in the bones and joints rubbing against each other. If your cracking joints are causing pain, swelling, or difficulty moving, consult your doctor today.
It might be the crack of your knuckles when you press on your fingers. Maybe your shoulder joint snaps when you lift your arm or your knee pops when you bend down. Most people have joints that make noise.
Another source of noise in a joint is from the tendons that connect muscles to the bones. Everyone's anatomy is a bit different, so some people may have bones that stick out a little more than others. When the tendons move over these bumpy areas, they can create a snapping sound.
As the cartilage wears down, the bones rub against each other. This causes pain, swelling and a grinding noise that you may be able to hear. This noise is a little different than your average knuckle popping. It may be more of a crunchy sound when you move.
The articular release of the metacarpophalangeal joint produces a typical cracking sound, resulting in what is commonly referred to as the cracking of knuckles. Despite over sixty years of research, the source of the knuckle cracking sound continues to be debated due to inconclusive experimental evidence as a result of limitations in the temporal resolution of non-invasive physiological imaging techniques. To support the available experimental data and shed light onto the source of the cracking sound, we have developed a mathematical model of the events leading to the generation of the sound. The model resolves the dynamics of a collapsing cavitation bubble in the synovial fluid inside a metacarpophalangeal joint during an articular release. The acoustic signature from the resulting bubble dynamics is shown to be consistent in both magnitude and dominant frequency with experimental measurements in the literature and with our own experiments, thus lending support for cavitation bubble collapse as the source of the cracking sound. Finally, the model also shows that only a partial collapse of the bubble is needed to replicate the experimentally observed acoustic spectra, thus allowing for bubbles to persist following the generation of sound as has been reported in recent experiments.