Working as an osteopath, I’ve found that one of the most common issues my patients ask about is clicking joints. Many people worry that the noise might be a sign of damage, or that it means they’re getting arthritis. Let’s have a look at whether this is a reasonable thing to worry about or an unnecessary concern.

Why do joints click?

Joints can click, crack, creak, or crunch for a variety of different reasons. In medical terminology, these noises are collectively known as “crepitus” (sometimes “crepitations”), and they can range from barely audible to startlingly loud. They can come from a wide variety of places. Hips, shoulders, and knees are often the source of unwanted noises, but smaller joints such as the temporomandibular joint, rib joints, and spinal joints may also make themselves heard. 

Perhaps most common is the kind of click you get when you crack your knuckles, for example. (Spinal manipulations performed by a chiropractor, osteopath, or physical therapist work via a similar mechanism.) This thought to be caused by changes in pressure in the joint fluid that lead to the formation of tiny bubbles of gas within the joint. I tell my patients that it’s a little like pulling a suction cup off a window. There’s still some debate over what actually causes the noise—whether it occurs as the bubbles are formed, or when they collapse—but either way, it doesn’t appear to be associated with any detectable damage. If you enjoy deliberately cracking your knuckles, you’ll also be relieved to hear that the evidence suggests people with this habit are no more likely to get osteoarthritis in the long term, and probably suffer no ill effects (except perhaps as a result of annoying the people around them). One study did find frequent knuckle cracking to be associated with swollen hands and reduced grip strength, but here we run into the causation vs. correlation dilemma again. It’s impossible to tell whether this study indicates a causal effect; whether people prone to painful joints in their hands are more likely to turn to joint cracking as a way to relieve them, or perhaps even that people with stronger hands find their knuckles harder to crack and are less likely to do it as a result, or maybe some other possibility we haven’t considered.

So that means it’s okay, then?

Not so fast. There are other causes of cracking joints, and not all of them so benign. Damage to or around a joint can often cause crepitus, so if there are other symptoms such as pain, weakness, instability, or loss of movement alongside the clicking, then there may indeed be a problem that needs attention. Broadly speaking, the source of the crepitus may come from either inside the joint capsule (intra-articular causes) or outside it (extra-articular).

Examples of intra-articular cracking might be from a meniscus tear in the knee or a labrum tear at the hip or shoulder. In some cases, it may be a sign of damage to the cartilage covering the joint surfaces (in other words, arthritis). If a fragment of damaged tissue gets folded awkwardly or trapped in the joint, it can cause clicking that is often painful, and sometimes locking of the joint. This sort of clicking will often need treatment to resolve.

Extra-articular causes would include things like tendons flicking over a bony prominence or a bursa (a bit like twanging a rubber band). This often happens with tendons around the hip, for example, and is thought to be associated with tight muscles around the joint. It is usually benign and happens only occasionally, but sometimes becomes persistent and occasionally painful. If it occurs often enough, the irritation may cause or contribute to tendonitis or bursitis.

How do I know which type of clicking it is, and what I should do about it?

A good physical therapist or orthopedist can often make an educated guess as to the source of the clicking, but it can be hard to know for sure exactly what’s causing it. Most of the time that doesn’t matter, though, because clicking that isn’t painful can almost always be safely ignored.

If there is pain, then that should be assessed and treated in the usual way. This might involve X-rays, MRI, CT or ultrasound scans, depending on the nature of the problem. Sometimes this investigation will reveal a structural defect which can be identified as the source of the clicking and can be treated. On other occasions, there may be nothing evident to explain the crepitus. A physical therapist can assess and treat factors such as muscle tension, weakness, imbalance or instability that may be associated with the problem, and sometimes this may help to reduce or eliminate the clicking alongside any pain, but it should be stressed that this is not always the case. The bad news is that your annoyingly clicky joint may remain annoyingly clicky, even after any pain or dysfunction has been resolved.

The verdict: usually FALSE. Joints can commonly click or crack for a number of different reasons, and in most cases, they’re completely normal and healthy. If there’s no pain, then it’s not an indication that there’s anything wrong. If you are getting pain along with the clicking, though, then that should be assessed.