Occasionally cracking your knuckles or other joints is very common and usually not harmful. If it is accompanied by pain or swelling or follows an injury, it may be caused by an underlying condition.

Contrary to the old wives’ tale, cracking your knuckles doesn’t cause arthritis. In fact, it can provide a feeling of relief and give you greater motion in a joint.

A 2018 study showed that theories of why and how joints crack are still debated scientifically, but advanced imaging technology has helped clarify the process. Joint cracking may become more noticeable as you age, as some of your cartilage wears away.

  • Technically, the cracking, popping, or grating sounds around a joint are known as crepitus, from the Latin word for “rattle.”
  • According to a small 2017 study, knuckle cracking has a reported occurrence of 25 percent to 45 percent in the United States.
  • The same small 2017 study above found that people with habit of knuckle cracking were “much more likely to crack other joints in their body.”
  • A different small 2017 study shared that the noise from joint cracking has not been linked to disease.

Joint cracking can have different causes. It’s common and is usually not an indication of a bone health condition. Exactly what causes the cracking or popping noise is the subject of many studies, but it’s still not completely understood.

Some natural causes of joint cracking are:

  • Sounds from muscle activity. As the muscle stretches, it can cause joint noises. For example, a tendon may snap in and out of place while you are stretching, exercising, dancing, or moving repetitively in your job.
  • Cartilage loss. This can occur from aging, which can roughen joint surfaces, resulting in joint noise with movement.
  • Arthritis. This can also cause cartilage degeneration and can result in joint noise.

What’s creating that cracking or popping noise isn’t fully known.

A traditional explanation is that pressure on a joint creates tiny bubbles in the synovial fluid, which pop when they form quickly. Your synovial fluid contains oxygen, nitrogen, and carbon dioxide and cushions your bones from rubbing against each other.

A 2015 study used real-time magnetic resonance imaging of joint cracking that showed the noise was related to cavity formation in the joint fluid, not collapse of a preexisting bubble. The technical term for this is “tribonucleation,” where two surfaces separate rapidly, leaving a gas cavity.

A 2018 study, however, developed a mathematical model of bubble dynamics and sound that proved consistent with the bubble collapse explanation.

Cracking your knuckles or other joints isn’t “bad,” but it may be annoying to the people around you if you do it frequently. In rare cases, if you’re cracking a joint too hard, such as in your back, you could injure yourself by pinching a nerve or straining a muscle.

According to a small 2011 study, the cracking process can give you a physical feeling of relief from pressure, whether you’re doing it yourself or having a chiropractor manipulate a bone.

The common myth that you’ll get arthritis in your hands if you crack your knuckles has proven to be just that — a myth — by another 2011 study. Studies have shown that knuckle cracking doesn’t thin your cartilage and isn’t likely to lead to osteoarthritis.

  • Mindfulness. If you have a habit of cracking your knuckles (or another joint) and want to stop, a first step is mindfulness. Keep track of when and possibly why you crack your knuckles, neck, or back.
  • Move more. A simple solution may be to move more. If you sit or stand a lot in one position, you can get stiff and crack your joints to help the stiffness. Take frequent breaks to move around. Aim to get up at least every half-hour if you sit at a desk all day.
  • Gentle stretching. Another solution is gentle stretching, which can move the synovial fluid around and lubricate your joints. There are dynamic and static stretches for all your joints. Here are some stretches for your hands.
  • Stress relief. If stress relief is involved in your joint cracking, try other calming measures, such as deep breathing, meditation, or a stress ball or fidget toy.
  • Exercise. Try to increase your exercise time to 150 minutes per week. Choose activities that suit your age and lifestyle. Any physical activity, such as housework, gardening, or short walks can be part of your exercise routine.

When joint cracking is accompanied by pain, swelling, or loss of mobility, it’s time to consult a medical professional. It could be a sign that you’ve damaged your cartilage, torn a ligament or tendon, or pinched a nerve in your back. In some cases, it could be a symptom of osteoarthritis or rheumatoid arthritis.

It’s best to find out and treat the underlying condition sooner for the best possible outcome.

Cracking or popping a joint is very common and usually not a symptom of disease. It shouldn’t be a source of worry, unless you have pain or swelling. Then it’s best to contact a health professional to determine the cause.

Theories about the physical mechanisms involved in bone cracking are in dispute.

If your bone cracking is excessive and you want to stop, there are remedies to try. The chief advice of orthopedists is to move more and get your synovial fluid moving.