Placebo as an ally
Bialosky and Colleagues have conducted and published results from several studies focused on understanding the mechanisms of spinal manipulation and other manual therapies.(1-5) In a recent article, these authors discuss a pertinent issue: the “placebo mechanisms of manual therapy.”(6) The authors suggest that known placebo mechanisms should be considered an important part of the pain-reducing effects observed from manually-delivered treatments.
Once thought to be inert, imparting no possible therapeutic effect, placebo treatments are now known to generate real neurophysiological responses. These “placebo” responses occur from the complex interplay of characteristics within the treatment context. For example, pain reducing effects attributed to placebo mechanisms can be influenced by expectations. Placebo mechanism induced pain reduction improves when individuals believe they receive effective treatment and/or have prior success with a given therapy. Carefully clarifying that many manual therapies induce other physiological effects contributing to clinical improvement, this article addresses a component of care that providers and researchers should recognize as potentially therapeutic.
“…placebo mechanisms may prime the nervous system to augment the effectiveness of manual therapy (MT) or may serve as the primary mechanism of MT. Manual therapists should continue to pursue clinical excellence, while understanding that the hours spent perfecting individual approaches may result in better outcomes not strictly from precise application but rather from improved contextual factors related to reputation, confidence, and therapeutic alliance. To best serve our pa¬tients, we must stop considering placebo as the benchmark of an ineffective inter¬vention and accept placebo mechanisms as part of any treatment for pain.”
Reference List
(1) Bialosky JE, George SZ, Bishop MD. How spinal manipulative therapy works: why ask why? J Orthop Sports Phys Ther 2008 Jun;38(6):293-5.
(2) Bialosky JE, Bishop MD, Robinson ME, Barabas JA, George SZ. The influence of expectation on spinal manipulation induced hypoalgesia: an experimental study in normal subjects. BMC Musculoskelet Disord 2008;9:19.
(3) Bialosky JE, Simon CB, Bishop MD, George SZ. Basis for spinal manipulative therapy: a physical therapist perspective. J Electromyogr Kinesiol 2012 Oct;22(5):643-7.
(4) Bialosky JE, Bishop MD, Price DD, Robinson ME, George SZ. The mechanisms of manual therapy in the treatment of musculoskeletal pain: a comprehensive model. Man Ther 2009 Oct;14(5):531-8.
(5) Coronado RA, Gay CW, Bialosky JE, Carnaby GD, Bishop MD, George SZ. Changes in pain sensitivity following spinal manipulation: a systematic review and meta-analysis. J Electromyogr Kinesiol 2012 Oct;22(5):752-67.
(6) Bialosky JE, Bishop MD, Penza CW. Placebo Mechanisms of Manual Therapy: A Sheep in Wolf’s Clothing? J Orthop Sports Phys Ther 2017 May;47(5):301-4.