Joint Cracking: Why Do Joints Crack, and When Should You See a Doctor?

Joint cracking is a common phenomenon that occurs in all the joints of the body—fingers, ankles, knees, hips, back... But not all joint noises are the same, nor do they all have the same meaning: we distinguish between cracking, creaking, and traumatic cracking, each with its own causes and level of concern.

Joint cracking: a harmless phenomenon

Joint cracking is the most common type of joint noise. It results from the formation and rapid expansion of a gas bubble (a process known as cavitation) within the fluid that lubricates the joint, caused by changes in pressure. This phenomenon is completely harmless: it does not cause osteoarthritis, even when it occurs daily, such as when you crack your knuckles. It is also this same mechanism that explains the sound heard during a manipulation performed by a therapist.

However, special caution is warranted if these cracking sounds occur after an injury, if they are painful, or if they are accompanied by swelling: in such cases, it is best to see a doctor.

Grinding, a symptom to watch for

Grinding (or creaking) is a second type of joint noise. It occurs mainly in the knee and corresponds to a sensation of catching or rubbing, which is audible and/or felt during joint movement. It can be a clinical sign of osteoarthritis.

Traumatic cracking: a warning sign

A sharp, sudden cracking sound occurring during an injury may, on the other hand, be a sign of a bone, ligament, or myofascial injury—that is, a detachment of muscle fibers from the fascial tissue that supports the muscle. In this case, it is imperative to see a doctor.

We remind you that the specialists at the Sports Medicine Center at Hôpital de La Tour are available to assist you.