By Anne Guignon, RDH, MPH, CSP
One key principle in assessing a workspace from an ergonomic perspective is the ability of a worker to perform tasks using a neutral body posture. A neutral body posture creates the strongest, most stable position for the body's spine, bones, discs, muscles, ligaments, and tendons.
Imagine looking at a side view of a person standing upright. Now draw a straight line from the top of their head through the tragus of the ear down through the middle of the shoulder, hip, and the ankle. This is the image of a neutral body posture.
In neutral posture, the head is balanced on the spine, which fully supports the weight. The average female head weighs around nine pounds, which is the only a few ounces more than a gallon of water. Men's heads typically weigh around 12 pounds. Visualize a bowling ball perched on the end of a stick. The spine and torso muscles are designed to support the weight of the head effortlessly. But this only works as long as we keep our head upright, which is an impossible task for all clinicians. Hygienists, dentists, and assistants are all challenged every time we deliver treatment.The business staff is challenged as well when seated at a desk.
Around 50 years ago, sit down dentistry became popular. Dental professionals all over the planet were soon sitting down for most of the day. Initially, it was thought that sitting would prove less stressful to workers, but the exact opposite happened. Clinicians who used to move around the patient now leaned forward to reach the workspace, often with hunched shoulders, twisted torsos, and heads bent forward and rotated, just to work in the patient's mouth.
Since the very nature of most clinical procedures involve moving forward to reach the patient's oral cavity, our positioning creates horrible stress on the clinician's body. Along with awkward, non-neutral body postures, we tend to sit in static postures for long periods of time doing forceful, repetitive procedures. In addition, it was found that seated clinicians took fewer breaks.1
Ergonomists suggest that postures that are within zero to 20 degrees from neutral positioning create the least stress on the upper body musculature and skeletal system. In today's world, it is entirely possible to create a workspace that allows us to work within this range. But we need the assistance of properly fitted magnification loupes with the correct working distance and declination angle as well as a seating system, such as a saddle, that allows us to sit both higher and closer.2
Modern lifestyles now include postural risk factors that were unheard of 25 years ago. Cell phones,3-6 computers,7-10 tablets,11-13 backpacks,14 and large, heavy purses are now considered a normal part of everyday life. The stress that these devices and items creates on our bodies is not only dangerous, but measurable. The number of scientific studies about effects of these products on the human body grows larger every day. 3-14 It is quite disconcerting to read studies that describe the impact to the human body using terms like "forward head posture syndrome," "texting neck," and "Blackberry thumb."7,8,12 Most of the research has been conducted on adolescents and young adults and the results are discouraging.
The muscles in the neck, shoulders and upper back are subjected to the force of 49 pounds when the head is positioned forward using a 45-degree head tilt. The actual impact is a physics calculation that takes into account the weight of the head, the length of the head from the top to the bend, and the forward flexion angle. This formula does not include the actual time spent in a compromised posture. People constantly check their mobile devices throughout the day. Take a look at the crazy head postures or have a friend take a photo of where you position your head when you're checking emails, texts, or chatting on your device.3-6,15
Over time, these postures can contribute to neck and shoulder pain,3-5,7,8,10,13 as well as headaches. In addition, device use:
- Plays a role in distracted driving, walking, and patient care18-20
- Plays havoc on our gait changes the center of gravity21-23
- Can lead to addiction,24,25 depression,26 and sleep disturbances.27
The cervical portion of the spine can also be remodeled, resulting in loss of a healthy cervical spinal curvature. Slouching leads to rounded shoulders that compromises blood flow to internal organs and reduces breathing efficiently as much as 30%.28,29
Learn to use a pair of properly fitted loupes. Add a saddle that fits your torso, will keep your spine in line, positions you closer to the patient, and facilitates deep, healthy breaths.
Put your devices on a counter or table at eye level. Use an easel to decrease the screen angle. Have a real conversation with a friend or colleague rather than sending another email or text. Find a Bluetooth headset that works with your cell phone. Use a stylus to type on a cell phone, and slow down the rate and compression on the thumb when typing on those super small screens.
Add the physical impact of practicing dental hygiene to the time spent on the combined number of devices we all use every day. When you factor in the total hours spent working in a dental office and using devices, it is clear that dental professionals are at substantially increased risk for developing potentially life-altering conditions that can have a profound impact on your daily life and your ability to earn a living.
Just like most of you, I, too, have a full array of modern devices. But I strive to work with them, using the least damaging posture possible. It's unrealistic to expect people to quit using devices or to quit working. However, more than ever before, we need to take responsibility for the impact on our bodies and make appropriate adjustments to how we work and how we communicate with each other. RDH
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ANNE NUGENT GUIGNON, RDH, MPH, CSP, provides popular programs, including topics on biofilms, power driven scaling, ergonomics, hypersensitivity, and remineralization. Recipient of the 2004 Mentor of the Year Award and the 2009 ADHA Irene Newman Award, Anne has practiced clinical dental hygiene in Houston since 1971, and can be contacted at [email protected].