(By Steven T. Tanaka, DC – from the February 2010 “The Scope”)
Sweetman BJ. Clicks and Clunks With Low Back Pain: What Do They Mean? A LIterature Review. International Musculoskeletal Medicine April 2009; 31(2):25-28.
ABSTRACT: Aim: To review knowledge about noises arising from the joints of the back, which can be felt or heard by back pain patients or those undergoing treatment for back pain. Materials and methods: A literature search relating to the clicks and clunks that can be heard or felt by patients with back pain either with normal movement, or during manipulation. The databases searched were Pubmed, Embase, TRIP, CINAHL, and Amed. The text terms click, clunk, and pop were used. In addition, experimental work was reviewed which aimed to elucidate the mechanism by which noises can be produced in synovial joints.
Results: Most of the literature deals with the mechanisms of clicks in joints in general and in finger joints in particular. In the spine, there are many references to the ‘popping’ of facet joints in the spine as a result of manipulative therapy. Research has centred around examination of cavitation and the formation of a gas bubble in the joint cavity when the joint surfaces are distracted. There was scant information about clicks and clunks in relationship to the presentation of back and neck pain. Studies have found no correlation between clicks and the typical electromyographic changes produced at manipulation, nor with therapeutic benefit. Conclusion: The significance of clicks and clunks in joints, whether occurring naturally or during treatment, remains uncertain.
COMMENTS: Unless something more finite comes along, most people accept idea that a gas cavity or bubble of carbon dioxide forms. When it collapses or cavitates, a sound is produced. Some have brought up the concept of capsular ligament “snap-back.”
Many studies have been done on the metacarpophalangeal joints. Some studies have been done on the cervical spine, lumbar spine, and sacro-iliac joints. Most agree that the sound comes from the zygapophyseal joints. In sacro-iliac joint and lumbar manipulation studies, the sound has been found to come from the lumbar spine, and sometimes from multiple levels ( due to the use of “lumbar roll”?).
I wonder what actually accounts for the difference between a well-done Gonstead adjustment and the higherpitched sound of many manipulative treatments and less than effective Gonstead adjustment attempts? We say what we think it is—sound of adjusting through the disc, rather than the apophyseal joints.