One of the first assessments I learned in Physical Therapy school was “the plumb line assessment”. This test helps us determine abnormalities from a “normal” static posture. These abnormalities supposedly lead to pain. There is even a website devoted to reviewing abnormalities from this and what it means. But what does static posture really tell us and how does it relate to our patients symptoms?
From my understanding of pain and modern neurophysiology, I argue that we can drop the plum line (and static posture assessments) professionally and can continue to have clinical success. I suspect we can stop assessing iliac crest height, head position and lumbar lordotic curves and be just ok. Why? Because it appears that these abnormalities are truly not abnormalities, but differences, which have little relationship with pain. In addition, our reliability for visual examination and assessment just stinks.
But you don’t have to take my word for it… what does the literature tell us?
A 2003 article assessed our ability to detect cervical and lumbar lordosis. It was appropriately titled, “Reliability of the visual assessment of cervical and lumbar lordosis: how good are we?”. The study was a blinded test-retest design to determine intra and interrater reliability values. The results? Our intrarater reliability is fair and our interrater reliability in determining “lordosis” from a pure visual assessment is POOR.
In 2010, a systematic review was published which assessed the relationship between awkward occupational postures and low back pain. This included a wide-range of “high risk” professions including scaffolders, nurses, podiatrists, firefighters, etc. The authors concluded there is strong evidence to support there is no relationship between prolonged static posturing and the development of low back pain. It would be expected that individuals with these professions would have higher incidences of low back pain but statistically , they did not.
Another article published in 2007 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.
The last article which I want to 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.”
In conclusion, it appears that static postures tell us little. If you have high success with its assessment and treatment, I guess you can keep using it…but for me, I have moved forward…
Fedorak C, Ashworth N, et al. Reliability of the visual assessment of cervical and lumbar lordosis: how good are we? Spine 2003; 28: 1857-1859.
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.