As a physical therapist that treats musculoskeletal conditions, it is not uncommon to have patients on a weekly basis concerned about popping or cracking they hear in their joints. For some, this popping and cracking may have been present for many years, for others it may have started occurring after an injury. If not accompanied by pain, it is typically perfectly normal as most of us have this sensation when we move different joints in our body.
But what are these sounds caused by? Studies have been done in the hands, where they have identified the formation of gas bubbles accompanying these sounds. When a joint is quickly moved, a phase change occurs where the synovial fluid changes to a nitrogen gas bubble leading to a popping or cracking sound. The ongoing theory is that this is occurring in other joints of the body such as the neck and back, not repositioning joints that are out of position. In fact studies have shown that cracking and popping the spine does not change the position of the vertebrae as shown with before and after X-rays.
Many healthcare practitioners, such as chiropractors, osteopathic physicians and physical therapists, purposefully position joints and provide a quick stretch with the goal of inducing the popping sound. This is commonly called manipulation. These specific manipulations are used to reduce pain, decreased muscle tightness and improve range of movement. Multiple studies performed by physical therapists and chiropractors show the positive benefits of manipulating the spine to reduce back pain when combined with lifestyle modification and exercise. Some healthcare providers make claims that manipulation of the spine repositions joints which can have an effect on many body systems and have positive effects on everything from allergies to colic in young children. Many studies have disproven those theories and show that only pain, range of motion and muscle relaxation are positively affected by manipulation of the spine.
It is always important to seek out a healthcare provider to perform a full examination and evaluation to determine if manipulation of the spine would be appropriate for you and determine if those sounds are perfectly normal. If you would like to learn more on this topic, keep your eyes peeled for an upcoming seminar this summer at Specialized PT in Candler.