Can Poorly Designed Office Furniture Worsen Back Pain?
Office furniture is designed to be attractive and durable, but not necessarily comfortable. Despite their promises, novel designs such as the knee chair have been proven in studies to be harder on the body than their conventional counterparts. This doesn’t mean ergonomics doesn’t matter, but we haven’t done a very good job of figuring out what ergonomic office furniture looks like.
Standards for office furniture have been in place for decades. European standards EN-527-1 specify dimensions for of office worktables and desks, based on body dimensions for adult men and women between the fifth and ninety-fifth percentiles. With this information in hand, designing office furniture for the average office worker shouldn’t be that complicated. But it is.
Sitting in poorly designed office chairs can have myriad adverse consequences, ranging from headache, neck and shoulder pain to low back pain, knee, and lower leg pain. Low back pain is a leading cause of physician visits and disability among adults with up to 90% of Americans experiencing low back pain at some point within their lifetimes. While physicians, employers and insurance companies have made it a priority to reduce the incidence and prevalence of workplace-related back pain, office furniture designers continue to struggle with the fundamental problem described above.
A complicating factor is the amount of time people sit at their desks without moving, something called “static sitting.” In addition, research has shown that persons with low back pain use large infrequent shifts in posture rather than small spinal movements (O’Keeffe et al., 2013). Studies on the benefits of “active sitting,” with small shifts in position to reduce strain on spinal, shoulder, head, and neck muscles have produced mixed results. However most physical therapists would agree that periodic breaks standing and moving around can make a difference.
Although they can’t agree on what the perfect office chair might look like, ergonomics engineers suggest the following features are important:
* Seat height adjustability
* Adjustable seat tilt up to 4 degrees
* Seat depth adjustability
* Adjustable backrest
* Backrest opening angle
* Chair recline or tilt
* Seat pan angle adjustability
* Adjustable lumbar support
* Height and width adjustable armrests
* Neck support with adjustable height and tilt
(Ivelic et al., 2002)
A group of researchers (O’Keeffe et al, 2013) studied the effects of a forward-inclined office chair with a saddle-type seat on back strain as compared to a traditional office chair. The forward-inclined chair had no backrest, but the forward tilt of the saddle seat was designed to maintain the spine in a neutral position. Results indicated that the novel design reduced back strain over the period of one hour compared to the conventional chair. Unfortunately, few people who sit in office chairs do so for just one hour at a time.
Given all this, what are the best recommendations for persons who spend most of the workday sitting in front of a computer?
* Try to stand up and move around every 30 minutes or so. If this is not possible, try to avoid sitting intervals longer than an hour.
* Stretch out your head and neck muscles. Stretches for head and neck muscles are available on this web site in the Exercises section.
* Take at least 3 walking breaks during the day. Put aside 5-10 minutes during your mid-morning, mid-afternoon, and lunch breaks to do this.
* Make sure that your worktable or desk is the proper height for typing. Your upper arms should be relaxed, and your elbows bent at a 90 degree angle. Often the desk is too high, causing excessive upper and lower back strain.
Finally, the importance of strengthening your core muscles, including the abdomen, glutes, obliques, paraspinals and scapular stabilizers. Look to the Exercises section of this website for additional information.