From: Work. 2010 Jan 1;35(1):3-14.
Little is known about how lumbar spine movement influences mechanical changes and the potential injurious effects of prolonged flexion associated with seated postures. The purpose of this study was to examine the postural responses and pain scores of low back pain sufferers compared with asymptomatic individuals during prolonged sitting in order to understand the biomechanical factors that may be associated with sitting induced low back pain.
Sixteen participants with sitting aggravated low back pain were age and gender matched with 16 asymptomatic participants. Tri-axial accelerometers were used to monitor lumbar spine angles during 90 minutes of seated computer work. Lumbar spine postures were examined using a movement pattern analysis of two types of postural adjustments, termed shifts (step-like adjustments larger than 5 degrees and fidgets (small change and return to approximately the same position).
The low back pain group reported large significant increases in low back pain while asymptomatic individuals reported little to no pain. On average, every participant fidgeted every 40 to 50 seconds. However, only the low back pain sufferers demonstrated a significant increase in the number of shifts over 90 minutes of seated work; the low back pain group shifted every 4 minutes in the last 30 minutes of sitting compared to every 10 minutes for the asymptomatic group. Low back pain sufferers also demonstrated larger amplitudes of shifts and fidgets when compared to the asymptomatic group.
Greater and more frequent movement was not beneficial and did not reduce pain in individuals with pre-existing low back pain. Future work to understand the biomechanical effects of proactively inducing movement may help to explain the paradox of the relationship between movement and pain.
Were the shift and fidget increases used to prevent further lower back pain. The article seems to relate sitting causes increased shifting and fidgeting in low back pain sufferers, however, the relationship is not clear. We note decreased pain associated with low back pain when using devices meant to increase movement like the backtivator and the active seat.