Upon a patient’s initial visit to a Physical Therapist, a static postural assessment is routinely performed.   Many therapists assess for “abnormalities” such as a forward head, rounded shoulders, decreased or increased spinal kyphotic/lordotic curves, abnormal pelvic positioning, etc.  They often associate any abnormal findings to their patient’s condition and attempt to treat by altering the found positional faults.  But in doing this, is there existing evidence that associates abnormalities found in static postures with pain?  In this article, I want to challenge this widely-accepted association by presenting a review of the current understanding of pain in addition to research which has assessed the relationship between posture and pain.

Quick Review of our Knowledge of Pain

In a post that I wrote for SportEX last year, I discussed the topic of pain.  I stated that one of the most essential things we must understand about pain is that nociception (which is input from nociceptors—unmylenated, danger receptors) is not necessary or sufficient for the experience of pain.  Pain is always an output from the brain based upon many different variables, and simply the brain’s suspicion that a tissue has the potential for damage, will cause it to react. The brain’s reaction can be based off a conglomerate of information including but not limited to: sensory input from the body, previous experiences of injury, social and/or environmental influences, expectations of consequences of the threat, beliefs/logic, etc.  Mechanical tissue deformation, which may occur with prolonged static posturing, may result in nociception, but according to the current models of pain, it will not always result in pain.  Other variables are likely necessary.

The first association made between posture and pain was likely based upon an older, Cartesian model of pain.  Pain was originally thought to be a bottom-up response, in which excessive stress on a tissue causes this negative sensation. This concept first originated in 1664 by Rene Descartes.  In the Treatise of Man Descartes theorised that pain was carried from nerve fibers to the brain and was the result of physical and mechanical deformation.   This theory (with slight modifications) was followed for centuries until the current models of pain, the Gate Control Theory and the Neuromatrix, were developed by Dr. Ronald Melzack.   Melzack proposed that pain was an output of the brain and is caused by much more than simply tissue damage.  His model challenged the belief that posture and pain are simply associated.  Its much more complex.

What does the research show?

A 2010 systematic review assessing the relationship between awkward occupational postures and low back pain found that there is strong evidence to support there is no relationship between the two.  This article included the review of eight high-quality studies that assessed individuals who worked in professions that forced  them to assume prolonged, static postures.  These professions included scaffolding, nursing, retail sales, podiatry, firefighting, etc.  It would be expected that individuals with these professions would have higher incidences of low back pain but statistically , they did not.

A 2007 article published in Manual Therapy assessed the relationship between sustained static posturing and postural neck pain.  Similar to the systematic review, the authors found that neck pain was not associated with the individuals habitual postures or kinesthetic sensibility.   The study came to this conclusion after assessing the habitual sitting posture, perception of good posture and postural repositioning error in symptomatic and asymptomatic individuals.

Another article published in 2000, challenged the concept of lumbopelvic imbalances and pain.  Many Physical Therapists believe that excessive lumbar lordosis is due to weak abdominal muscles in combination with shortened lumbar extensor and hip flexors muscles, which in turn leads to pain. This positional fault leads to an anterior pelvic tilt which should be addressed through abdominal stabilization (often utilizing  the infamous posterior pelvic tilt).   The article assessed 30 men and women who had chronic low back pain (CLBP).  It assessed the location of pelvic inclination and magnitude of lordosis and found that in individuals with CLBP, there was no more standing lumbar lordosis or pelvic inclination than their counterparts with healthy backs.  In patients with CLBP, the magnitude of the lumbar lordosis and pelvic inclination in standing was not associated with the force production of the abdominal muscles. The authors go as far as concluding,

“Abdominal muscle strengthening exercises are routinely recommended by physical therapists to correct faulty standing posture in patients with CLBP. These recommendations are often based on assessment of standing posture. We urge physical therapists to avoid prescribing therapeutic exercise programs of muscle strengthening of abdominal muscles in patients with CLBP based solely on assessment of relaxed standing posture.”

So what does this mean?

I would argue that we spend too much time focusing on holding static postures and less time on movement.  It appears that there is little evidence to support the notion that poor posture leads to pain.  I recommend to my patients to find positions of comfort.  When those positions get uncomfortable, move and find another position of comfort.  We were built to move.

The author: Joe Brence, physical therapist

Joseph Brence is a doctor of physical therapy from Pennsylvania, USA. He is currently a director of two facilities in Pittsburgh and takes a manual approach to patient care. He is also a contributor to www.physiotherapyinfo.com and http://www. theptproject.com and is currently working on multiple research projects which he will present to the sportEX community as they are published. To read Joseph’s monthly contributions, click the following link http://eepurl.com/bRGmj.

References

• Merskey H, Bogduk N. Classification of Chronic Pain. 2nd ed. Seattle: IASP; 1994.
• Melzack R, Katz J. The Gate Control Theory: Reaching for the Brain. In: Craig KD, Hadjistavropoulos T. Pain: psychological perspectives. Mahwah, N.J: Lawrence Erlbaum Associates, Publishers; 2004.
• Iannetti GD, Mouraux A. From the neuromatrix to the pain matrix (and back). Exp Brain Res 2010; 205; 1-12.
• Moseley GL. A pain neuromatrix approach to patients with chronic pain. Manual Therapy 2003;8:130-140.
• Roffey DM, Wai EK, Bishop P. Causal assessment of awkward occupational postures and low back pain: results of a systematic review. The Spine Journal 2010: 10; 89-99.
• Edmondston SJ, Chan HY, Ngai GC, et al. Postural neck pain: An investigation of habitual sitting posture, perception of ‘good’ posture, and cervicothoracic kinaesthesia. Manual Therapy 2007: 12; 363-371.
•  Youdas JW,  Garrett TR,  Egan KS, et al. Lumbar Lordosis and Pelvic Inclination in Adults With Chronic Low Back Pain. Physical Therapy2000: 80; 261-275.

Source: http://www.sportex.net/blog/2013/03/is-static-posture-related-to-pain-probably-not/.

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