What is cracking joints?
Intra-articular creaking, or otherwise known as cracking, is the sound that can be heard inside a joint.
This sound is produced in joint movements and the neck is an area with quite frequent such sounds.
The vast majority of people have experienced this sensation involuntarily, while many seek it with specific movements or empirical manipulations.
For example, turning the head abruptly to park our car can give us the infamous crack as an articular response.
Also, many therapists seek to hear this sound as an indication of the success of a manual therapy procedure (something which is logically incorrect but belongs to another discussion that we will have in a future article).
Therefore, we can define a joint creak as any sensation or impact sound that may be produced within a joint during its active or passive movement.
What causes ‘crack’?
The anatomy of the joint is what provides the explanation for the production of cracks. Taking into account that the articular surfaces are covered by cartilage, that there is synovial fluid inside the joint for lubrication, and that contractile elements such as muscles, tendons and ligaments are attached around the joint, the following possible reasons for the appearance of creaking arise:
1)Intra-articular changes pressure.
Small air bubbles may form and then burst, causing the characteristic cracking sound. These bubbles are created by changes in hydrostatic pressure within the synovial fluid. We often hear such a sound even in the small joints of the fingers. The more superficial the joints, the more intense the creaking sound will be.
This process takes place either involuntarily during normal movement or voluntarily after, for example, manipulation by a manual therapy therapist.
The medical community has been debating for several years whether air bubbles may be the ones that cause the production of intra-articular sound when they rupture.
2) Movement and friction of a ligament or tendon around a bone.
Ligaments and tendons are known to attach to bones. In some cases, a joint movement can cause the connective tissue of the contractile structure to rub against the bone to which it attaches.
This occurs when the muscle or ligament system in the area is quite inelastic, due to injury or age. The result is again the creaking sound.
3)Friction between bones
As joints degenerate due to age or pathologies (e.g. osteoarthritis), the protective tissue of the joint surfaces wears away. This means that in some cases, the absence of sufficient articular cartilage can translate into friction of the joint surfaces against each other.
Of course, in this case, the joint creaking is accompanied by pain and discomfort. In fact, in advanced cases, there is also a reduction in the mobility of the area, as a protective countermeasure of the body.
Joint crepitus can be due to one of the above causes or it can be the result of a combination of them. Of course, it can be observed in any movable joint, however, the joints of the shoulder, neck, knee and fingers are the ones with the highest frequency of occurrence.
What is the usual feeling?
Joint fusion is a procedure that is usually painless. This automatically means that it is not harmful or dangerous to the health of the joint. In fact, for many people it is a procedure that provides temporary relief and a small increase in range of motion.
Sometimes, however, pain may coexist, either in the form of discomfort or as an intense stabbing pain. Here, the person should be careful about the etiology of the production of joint sounds.
People who experience pain naturally also experience negative thoughts and stress regarding the production of intra-articular sounds.
Many times such sounds can result in an unnecessary reduction in mobility or a change in the biomechanics of an area.
This occurs due to the person’s fear and concern that an injury is being caused or there is some pathology.
A thorough evaluation by a specialist will resolve any doubts and reveal the true extent of the significance of the joint creaking.
What is the frequency of occurrence?
Joint creaking can occur at any age, however, at older ages the likelihood of it occurring in one or more joints increases significantly.
The intensity and frequency also vary. Most people experience intense crying for a specific period of their lives, e.g. for 2-3 months after an injury, and then this phenomenon is observed occasionally, as it is for all of us.
Of course, there are many who experience intra-articular sounds on a daily basis and as frequently as the movements of an important joint such as the neck.
Therefore, we cannot say how often it is “normal” nor can we blame creaking for the appearance of joint pathologies such as arthritis. However, creaking may sometimes be a sign that a musculoskeletal pathology is hidden and we must act preventively with a simple evaluation by a specialist.
Morochliadis Stefanos
Physiotherapist Bcs, MT, RT, Formthotics specialist
