A 2018 study found that using standing posture assessments to find whether someone has low back pain to be “irreproducible.” The researchers of this study, led by Dr. Hendrik Schmidt from Charité–Universitätsmedizinin Berlin wrote that such lack of reproducible results can lead to misinterpretation of imaging measurements, wrong diagnoses and possibly unnecessary treatment for pain.
“Back pain patients and athletes did not show a different behavior to asymptomatic non-athletes,” Hendrik and his colleagues wrote. In other words, if you were to examine hundreds of people in a day by looking at their standing posture, you would not be able to accurately identify who has low back pain and who does not. This is because of the variations that humans have, from standing posture to anatomical structures like the pelvis.
The researchers made four hypotheses:
1. “The variability in lumbar lordosis and sacrum orientation in repetitive upright standing postures decreases with the number of standing phases.” This means test subjects will become familiar with the test setup and should know how to pose for the tests, which would decrease variability.
2. “Age and gender significantly affect the variation in lumbar lordosis and sacrum orientation.” This is based on a 2014 and 2015 studies that found a correlation between gender and age with lumbar lordosis and sacrum orientation.
3. “[Low back pain] patients show a significantly greater variability in lumbar lordosis and sacrum orientation than asymptomatic subjects due to pain-related functional adaptation and/or pain and movement avoidance behaviour.”
4. “Athletes with a higher and more uniform fitness level stand more reproducible than non-athletes.” The researchers assumed that athletes have better neuromuscular and motor control that allow them to have more stability and reproducible posture than non-athletes, especially those with low back pain.
The researchers recruited 332 subjects (187 women; 145 men) who are non-athletes with no back pain for at least six months and had no spinal or hip surgery. These people were also part of a cohort study that involved measurement of the lumbar spine posture and its movement. They also recruited 21 soccer players without back pain and 83 patients with chronic low back pain for more than a year. Sensors were placed along the thoracic and lumbar spines and the sacrum. These sensors were sensitive to the changing curvature of the spine.
Then each subject performed four exercises in a standing position: Forward flexion, back extension, left and right lateral bend, and left and right horizontal rotation. Each exercise was repeated three times before moving on to the next.
Before starting each exercise, they had to stand upright and relaxed with straight knees for two seconds. During those two seconds, their lower back curve and the position of their sacrum were measured and an average value was calculated.
The results do not find significant differences between the back-pain free group and those with low back pain. The joint angles were similar between the asymptomatic and back pain groups and between the non-athlete and athletic group. Eeach time the subject performed an exercise and return to being a statue for two seconds, no two standing postures were alike.
“In six repeated standing phases, 51% of all asymptomatic women and men showed on average variations in lumbar lordosis between 10% and 20%; 20% between 20% and 30%; and 6% between 30% and 40%,” the researchers wrote. “In the sacrum orientation, 42% of all asymptomatic women and 29% of all asymptomatic men revealed variations of 10% to 20%. Interestingly, 18% of all asymptomatic men showed variations in sacrum orientation [of less than] 40%. For variations of 10–20%, sacrum orientation and lumbar lordosis did not show significant differences between repeated measurements.”
The study contradicts the researchers’ hypotheses.
1. There was hardly any differences between those with back pain and those who do not;
2. Age and gender did not affect the variations in the standing posture;
3. Low back pain patients did not have greater variability than those with no pain
4. Trained athletes had just as much variation as non-athletes.
“Therefore, it is important to understand that the variability in standing is not predictable but random, and thus does not reflect an individual specific behavioral pattern which can be reduced, for example, by repeated standing phases,” the researchers wrote.
Related: Sacroiliac Joint Pain, an Updated Narrative
Related: Why Massage Therapists Should Understand How Pain Works
Nick Ng, BA
Nick Ng is the editor of Massage & Fitness Jounal and the managing editor for My Neighborhood News Network.
An alumni from San Diego State University with a bachelor’s degree in graphic communications, Nick had completed his massage therapy training at International Professional School of Bodywork in San Diego in 2014. In 2021, he earned an associate’s degree in journalism at Palomar College.
When he gets a chance, he enjoys weightlifting at the gym, salsa dancing, and exploring new areas in the Puget Sound area in Washington state.
