If It Ain’t Broke…It Probably Will Be Soon
Following the significant interest displayed after last week’s post about proper head and neck posture, I figured it only apropos to follow it up with a piece about workstation ergonomics, aka how to set up your desk so that you don’t need a back brace in the next five years. For starters, let’s all agree on the fact that your desk and chair should be able to be adjusted to fit you, NOT the other way around. I realize that companies can be cheap, so making your 5×5 workspace truly fit you may take some creativity and cash on your part, but considering it’s where you spend the majority of your day, it’s a worthwhile investment. Disclaimer: I am not a professional desk and/or chair selector, nor do I spend my free time searching through the National Chair and Desk Database (no, that does not actually exist) for the most up-to-date models. I’m just sharing with you my knowledge as a PT regarding fundamental ergonomics for slaving away at that desk all day. This piece is to serve as a resource for how to modify what you already have. This is not a reference for which chair to buy or which desk is all the rave or some data resource to use in your quest to get your boss to buy you that $10,000 treadmill desk.
The Occupational Safety & Health Administration (OSHA) roughly defines ergonomics as “fitting a job to a person,” which ultimately “helps lessen muscle fatigue, increases productivity and reduces the number and severity of work-related musculoskeletal disorders.” Translation: your job shouldn’t be killing you. An ergonomic workstation does not just offer a position of comfort, it places joints and muscles in neutral positions to minimize stress and injury. For more information about your rights as a worker, click here.
Ok, let’s get down to the good stuff.
Seat: So, for those of you with a traditional sitting desk it’s difficult to discuss the specifics of a chair without referencing your desk, but I’m going to attempt to break it down for you one part at a time. When it comes to chairs, the more adjustable features it has, the better. Proper chair height should allow your feet to rest comfortably on the floor with your knees and hips bent to 90 degrees. If you are vertically challenged and don’t have workstation options that will let you sit in your chair with your feet on the floor while also being able to reach your desk, bring the floor to your feet by using a footrest. For those of you looking to not spend any money, books or boxes can also be used. For those of you who insist upon crossing your legs or sitting with your leg tucked under your butt, STOP IT.
Regarding workstation posture I often tell my patients to think of ‘L’s, as this is the shape your hips, knees, and ankles should form. It should be noted that your chair won’t be actually set to a 90 degree angle between the seat and backrest, as most people prefer a slightly reclined position, generally about 15 degrees from a fully upright position. With your back against the backrest you should have about a 2-3 inches of clearance between the front edge of the seat and the back of your knees. This is recommended so as to prevent pinching or compression of any nerves and important structures in the back of your knee. A good chair should have an adjustability feature that allows you to move the backrest either forward or backwards to ensure your legs are fully supported while allowing you to maintain contact with the backrest. If your chair doesn’t have this feature and you’re on the shorter side, consider using a pillow behind your back.
People often inquire about using a therapy/swiss ball as chair. While everyone is entitled to their opinion, my response is always the same: “Would you stand on a BOSU all day?” The core endurance required to sit on a therapy all day is tremendous and quite frankly beyond the capabilities of nearly all human beings. Sit on a proper chair, get your work done faster because your back and neck aren’t hurting from sitting on that dumb ball, then use your saved time to go to the gym and properly work on your core.
Backrest: Despite what many people would have you think, your back is actually supposed to rest against the backrest…that’s why it’s called a backrest. Now that you’re actually using it, you want to make sure that it fits the curve of your back. In previous posts I’ve discussed the natural curvatures of the spine, with the lumbar spine having what we refer to as a lordosis. We maintain this curve even when sitting, and thus it’s important that the backrest of the chair have some sort of lumbar support feature. Generally this just comes in the form of a convex curvature at the lower part of the chair. Keep in mind that everyone’s lumbar curvature is different, and to that end it’s generally not a bad idea to pretend that you’re Goldilocks and purchase a lumbar support cushion that’s “just right.” Again, I’m not a professional shopper. Do your homework and figure out which support would be best for you.
Regarding backrest height, support of the lumbar spine is the most important factor. Chairs with tall backrests that support the shoulder are better for reclining, while chairs with backrests that support the lower back and a portion of the upper back are generally appropriate for the average desk jockey. Again, I’m not here to tell you which chair to buy, just how to adjust what you already have.
Armrest: Here is where things start to get tricky. In general you want your armrests to be positioned at a height that allows your forearms to rest comfortably on them, forming roughly a 90-degree angle at your elbow. In this position your shoulders should be relaxed, and not jammed up near your ears. The armrests should also be positioned so as to allow your upper arms to remain close to your body while being wide enough to allow you to actually get and out of your chair. If your chair has shorter, table-length arm rests you’ll be able to get your chair closer to your desk and have an easier time getting that workstation to fit your body. As a general rule, only your elbows and/or a portion of your forearm area needs to be supported for desk work. If your armrests aren’t adjustable and interfere more than help, feel free to just take them off.
Once seated in your perfectly ergonomically adjusted chair, your computer or main work area should be directly ahead of you. If your computer is off to the side, and you spend 8+ hours a day typing with your head turned to the right, please don’t come to my office asking why you have neck pain. Everything that you use with regularity should be directly in front of you. Additionally, you should think of setting your paperwork and accessories up like stadium seating, with the most important and most used items closer to you and in the center. Those things you use with less frequency can be farther away from you, but ideally should still be within an arms-length away so that you don’t have to reach or twist very much to get them.
The Standing Desk
Standing desks are being used more and more these days, and it’s a movement I fully support. Realistically the set up of the actual desktop can and should remain the same, with the only thing changing being the height of the desk. The desk height should be adjusted so that the user is able to maintain that same 90-degree angle at their elbow with their shoulders in a relaxed position while using the keyboard or mouse. There are a variety of different standing desk options on the market right now, ranging from less than $100 to a couple thousand dollars. In reality, you want to avoid the standing desk options that only lift the computer and keyboard, as this will force you to have your phone/paperwork/books/etc at a different level than computer and create all types of ergonomic errors. A simple desk that allows the entire work surface to move up and down is sufficient and will generally run you a couple hundred bucks. Regarding proper standing posture while at that desk, refer to these (1, 2, 3) previous MOTW articles. Continue reading below for proper desktop accessory placement, as the guidelines are the same whether you are sitting or standing.
The Monitor: Most people don’t have the luxury being able to adjust the height of their desk, however, you can adjust the height of your computer monitor. The top edge of your monitor should be at eye level, allowing for a slight downward tilt of your head while you’re typing and working. Having the computer at this height not only allows you to maintain that gentle chin tuck I discussed in last week’s MOTW, but it’s also easier for your eyes to track downward than upward, requiring your neck and upper back to do less work. For those of you working on a laptop, I recommend putting the laptop on a stand so that the top of the screen is at eye level and then using a wired or wireless keyboard. According to OSHA, the recommended viewing distance (the distance from your eyes to the screen) is 20-40 inches. A good rule of thumb is that you should be able to touch your screen with your arm extended straight ahead of you. As for viewing angle, a screen tilt of 10-20 degrees is recommended.
The Keyboard: The keyboard height and distance from your body should be such that you can maintain, you guessed it, a 90 degree angle at your elbows with your wrists in a neutral position. Often times this is best accomplished with a keyboard tray, but everyone seems to hate them, so if you fall into this category, I’d recommend raising your chair and screen height and then and putting something under your feet while your keyboard rests on the desk surface.
The Mouse: This is one area where I see a lot of people doing their best to injure their shoulders and elbows and score a trip to physical therapy. A mouse that is far away forces the user to stress their elbow and shoulder unnecessarily as their arm is not supported by either the table or armrests. The mouse should be in the same plane as the keyboard, allowing you to maintain a 90-degree angle at your elbow, your wrist in a neutral position, and your upper arm close to your body. Small keyboard trays that don’t have room for a mouse actually do more harm than good, so either get a smaller keyboard, a larger keyboard tray, an attachable mouse tray, or ditch the whole thing all together. Regarding track pads versus trackballs versus a traditional mouse, they all come with their pitfalls and spending too much time using any of them can lead to a repetitive stress injury. My advice is to use whatever allows you personally to maintain that neutral wrist position and requires you to lift your fingers the least.
It’s 2014, get a headset. Bluetooth, wired, those easily broken iPhone headphones, I don’t care, just please stop craning your neck to the side in a feeble attempt to pinch your phone between your ear and your neck à la Zack Morris.
Regardless of whether you’re sitting or standing at your desk, the human body does not like to maintain a static position for extended amounts of time. Get up, stretch out, move around at least every 20-30 minutes.
Check yo’self: Have a colleague take a picture of you from the side, back, and front (if possible) while you’re at your desk. Candid shots work best for this to prevent you from lying to the camera and making your posture better than it actually is. Compare those photos with the information I’ve just given you, and make all the necessary adjustments. This is one time when the “if it ain’t broke don’t fix it” mantra isn’t so applicable. Those bad ergonomics are just a carpal tunnel wrist splint waiting to happen. Modify your workstation to fit your body, and make sure you’re taking breaks throughout the day. Your body will thank you.