Joint cracking or popping occurs when air escapes from the joint space. Synovial fluid is the lining that lubricates the joints; it contains gases such as oxygen, nitrogen, and carbon dioxide. The gas is released from the joint with specific movements, and an audible "pop" is heard.
Joint space cracking or popping is caused by releasing gases from the synovial fluid, which lubricates and lines the joints.
With aging, the cartilage in the joint thins, leading to more popping and cracking.
There is no evidence that cracking the joints of your hands (knuckles) is dangerous; however, it is inadvisable to purposely crack or pop your spinal areas (neck and back).
If there is continuous joint cracking or popping, and it is associated with pain, swelling, or limited range of motion, see your physician or medical provider.
Is the audible "pop" or "crack" from the same mechanism I hear at the chiropractor?
When a chiropractor "manipulates" the joints in the neck and back, gasses are released, causing the noise you hear.
Why do my joints crack more as I age?
Cartilage is the strong, connective tissue present inside the joint that lines the joint space and prevents the bones from grinding, in addition to other purposes throughout the body. With age, the joint cartilage wears down, resulting in more cracking.
Is it bad to crack your finger joints on purpose?
Numerous studies have been done to see if there are any short-term or long-term side effects to purposefully cracking your fingers, and none have been found.
The concern that arthritis or thinning cartilage will result from cracking or popping your finger joints is unfounded.
Is it serious if I hear cracking in my fingers or my larger joints like the shoulder, knee, or elbow?
Much research has been done, and the consensus is that if the cracking does not produce pain, swelling, limited range of motion, or occurs after some type of trauma, it is probably not a concern.
What about cracking my neck or back on my own? Is that bad?
Yes, it is bad since cracking your back or neck on purpose is different from popping your fingers; the audible pop you hear could be from a properly positioned joint, and you have now misaligned it on your own.
Thus, do not try to crack or pop your neck or back on your own; it should only be performed by a qualified individual, such as a chiropractor.
What about that cracking or popping noise I hear when I exercise?
The noises from exercising arise from the musculoskeletal system, which consists of several structures:
- Ligaments connect bone to other bones
- Tendons are the thin ends of muscles that attach to bone
- Cartilage (already mentioned above)
When we exercise, rubbing or friction of the above structures produces a popping sound. It can be the tendons on the bones, the ligaments against the tendons, or any combination of structures.
What is the physician (provider) workup for popping or cracking sounds?
- A physical exam should focus on where the popping or cracking noise originates, checking for areas of tenderness, swelling, or limited range of motion.
- Full laboratory tests can assist with diagnosing many serious conditions that could be present.
- Plain X-rays are needed to evaluate the underlying bones for serious conditions such as arthritis, a fracture (break), cancer, bone spurs (prominent bony areas at the ends of the bones), and osteoporosis (thinning of the bones that can cause them to break easier than expected).
- Cancer from a different organ that has spread to the bone, called metastatic, can appear as "punched out" lesions on x-rays. The punched-out lesions look like raindrops hitting a surface and splashing.
- However, plain X-rays only show bones, not the musculoskeletal system's other components (stated above). Therefore, to view these structures (muscles, ligaments, tendons, or cartilage), a computed tomography (CT or CAT) scan or magnetic resonance imaging (MRI) scan needs to be done. These are discussed below.
- CT scans produce computerized images from different angles, allowing comprehensive three-dimensional viewing. However, a CT scan does not provide as much detail as an MRI.
- Magnetic Resonance Imaging (MRI) combines magnetic and radio waves to produce computerized three-dimensional images. It is considered the "gold standard" for evaluations of soft tissues and bone.
- Ultrasound can show inflammation inside the joint space. Unlike CT or MRI scans, ultrasound recordings are made in “real-time” and can show the movement of muscles, tendons, or structures inside the joints.
Once a serious condition is ruled out, what can I do to avoid joint cracking or popping?
Mindfulness is essential. You need to be aware if you are popping a joint on purpose.
Movement is also key to preventing cracking and popping by keeping the joints lubricated. For example, you may have noticed that your knees will crack more after prolonged sitting or any other joint in a static position, so keep them moving to help prevent the noises.
Exercising regularly is a terrific way to keep the muscles, joints, and other structures moving and lubricated. In addition, excess weight can lead to joint stresses and muscle tightening, so eating a healthy diet to maintain weight is highly recommended.
Often, the popping noise is due to tight muscles, so some easy stretches are advisable when there is continued popping.