Home-Work Environment, Posture and Postural Stress (Part 1)

We are all experiencing unprecedented times due to ‘Covid-19’ and adjusting to the new normal way of life. Currently, some of us are setting up makeshift workstations at home for the next few weeks, because not all of us are prepared with a home office that is ergonomically designed!

Most workplaces generally spend a lot of money and resources to set up their work environment because of the impact it has on our physiological and mental well being. This narrative will discuss the following topics in two parts.

Part 1:

-What are the implications of an incorrect workstation setup

-What is posture?

-How do we measure posture?

Part 2:

-What is ‘poor posture’ and does ‘poor posture’ cause pain

-What is postural stress?

-How do we avoid postural stress?

What are the implications of an incorrect workstation setup?

 Normally, it wouldn’t matter much as we will never be stuck in one place for very a long duration. So even if we make do with a less efficient workstation, it would not have such an impact on our posture or musculoskeletal health. But now we are talking about the next few weeks if not more for extended hours each day.

 To me, one of the most significant physiological and psychological impact of this lock down is the physical stagnation and sensory deprivation we will experience from the constrained environment within the four walls of our home.

Consequently, we might find ourselves less body-aware and chances are that we might fall into a lazy pattern and develop habits that may encourage holding sub optimal postures for a prolonged period.

For example, we might find ourselves using work laptops from the couch or from the comfort of our bed. Now imagine working for several hours a day for the next few weeks by holding such resting postures in such constricted spaces. The cumulative effect of such workstations is most likely to result in neck strains, shoulder stiffness, lower back pains and even wrist strains. These musculoskeletal strains are grouped under the umbrella term called occupational overuse syndromes (OOS). Whenever we talk about occupational injuries, posture comes under scrutiny.

What is posture?

Posture is a dynamic process that is determined by an individual’s interaction with a specific task and the environment. For example, when adopting a strategy that is biomechanically effective in one circumstance but may not be appropriate in another, people will adjust their posture in accordance to the task or the environmental demands.

Hypothetically speaking, even if someone has ‘good’ or ideal posture, can he hold it for the next 8 hours without any musculoskeletal discomfort? The answer is probably a No!! This is because when we discuss posture, one of the fundamental concepts often being overlooked is ‘movement’ or more specifically the lack of it.

Lack of joint excursion or reduced joint range of motion for prolonged periods may cause muscular fatigue, overall systemic stress and local tissue damage which may manifest as perceived pain. Therefore, going back to the definition given at the beginning of this topic, there is no one ideal posture and your best posture is your next posture! So, if there is no gold standard for correct posture, why do we keep chasing good posture and, more importantly, what are we looking for in postural assessments?

 

How do we measure posture?

Before we discuss the measuring tools, we need to understand what we are measuring. Let’s briefly look at our spinal anatomy, the structures of our spine is “S” shaped and has four alternating curvatures in each spinal segment, convex/outward and concave/inward. This structural orientation of the spine helps it to distribute the load of the axial skeleton and gives the spine its flexibility. The pelvis also has the ability to tilt anteriorly or posteriorly in reference to the spine.

When we measure static or standing postures, we look at the spinal curvature and pelvic alignment by using an imaginary “plumb line” that is drawn from the middle of the ears and goes through the middle of the shoulders, pelvis, knees and finally end at the “lateral malleolus” outside of our ankle bone. This postural imaginary line is drawn in order to find our neutral spine. (Kendall et al 1952)1. Over the years, this imaginary postural alignment has drawn much attention and has been a source of postural fear mongering. For example, there is a common myth that lumbar lordosis (spinal curvature) and its relationship with anterior pelvic tilt (pelvic orientation) is responsible for back pain, this is a common diagnosis that arises from postural assessments.

Although static standing postural assessments is carried out in many clinics and gyms around the globe, yet its accuracy is highly debatable. A study investigated the accuracy of static postural assessments in measuring the difference of spinal curvature and pelvic orientation) in standing postures. This study by (Schimdt et al 2018)2 finds that each time we stand up, we do it slightly differently (changes in spinal curvature – postural variability), therefore static postural assessments may give us different results each time we stand.

This is a large scale study that compared both asymptomatic population (people without pain, non- athletes n-332 & athletes n-21) and symptomatic population (people with pain, n-83) and finds an interesting fact that this postural variability is consistent across all participants. Therefore, people in pain do not significantly stand differently from people without lower back pain.

Another study investigated lumbo-pelvic posture and spinal movement patterns by using a wireless wearable unit. This study finds no significant postural differences in pelvic alignment or spinal range of motion in people with and without chronic lower back pain. Three different test raters find that postural inconsistency to be a common occurrence within sessions in both set of participants. The author states that “this variability needs to be considered when interpreting posture and movement changes.” (Laird et al 2016)3

The above-mentioned studies have demonstrated that movement or postural variation is a common occurrence. People do not hold any one posture for a long period of time and, therefore, there is no one ‘ideal’ or ‘correct’ posture. Furthermore, current evidence indicates that there is no or little association between posture and perceived pain.

Hence, next time someone tells you that your posture is causing you back pain, please take it with a grain of salt.

 

Cont. in Part2….

References:

1.Kendall, H. O., & Kendall, F. P. (1952). Posture and pain. Krieger Pub Co.

2.Schmidt, H., Bashkuev, M., Weerts, J., Graichen, F., Altenscheidt, J., Maier, C., & Reitmaier, S. (2018). How do we stand? Variations during repeated standing phases of asymptomatic subjects and low back pain patients. Journal of biomechanics70, 67-76.

3.Laird, R. A., Kent, P., & Keating, J. L. (2016). How consistent are lordosis, range of movement and lumbo-pelvic rhythm in people with and without back pain?. BMC musculoskeletal disorders17(1), 403.

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