Seating modification, back posture and change in lower back pain amongst occupational car drivers with chronic lower back pain

Low back pain has been described as the major cause of disability worldwide (1). In Australia, approximately 10% of the population experience substantial disability from low back pain in any six-month period (2). Low back pain also contributes to considerable economic strain. In the most recent Australian economic burden study, the estimated cost of low back pain in a one year period was AU$9.17 billion (2). AU$8.15 billion of this burden of disease was driven by loss of earnings and productivity costs, where people were not able to engage in their usual occupations (2).

The notion that poor sitting posture is a risk factor for low back pain is reported widely in the literature (3-5). There is a substantial evidence base that has examined postures adopted in static sitting and relationships with low back pain (6-9). Comparatively less work however, has been undertaken on more dynamic sitting behaviour that may be required as part of occupational activities, such as driving an automobile.

This project measured pelvic, trunk and lumbar flexion/extension and pelvic, trunk and lumbar lateral flexion through real time lumbar motion monitoring. Eleven occupational drivers with reported low back pain were recruited for the study and were monitored whilst driving their standard vehicle with the standard car seat and then a modified car seat (either replacement of the standard car seat with a modified car seat or the placement of a lumbar support roll in the standard car seat).
Main findings:
1. Our systematic review identified that a relationship between low back pain and postures assumed while driving may exist, but further research using more robust and reproducible measurement approaches needs to be undertaken to confirm this.
2. Our reliability study found that driving posture data is best represented by mean lumbar flexion, collected at any time within a work shift, but not within the first five minutes of any drive.
3. Our intervention study found that car seat modifications can lead to significant changes to pelvic flexion during driving. The effect that this change in posture then has on resultant pain requires further investigation.
Implications:
With a large number of Australian’s driving as a part of their occupation the mechanisms by which back pain may be reduced through car seat modification needs to be identified. Establishing interventions that may allow low back posture to be modified may reduce the risk of developing back pain for non-sufferers and may allow those with back pain to work more comfortably. This research has established that modifications to a standard car seat can significantly change pelvic flexion angles, with further research required to see the follow on effect to resultant pain. These modifications may be as simple as inserting an “off the shelf” lumbar support role for some sufferers. The beneficiaries of this work may include drivers of all workplace vehicles including taxi drivers, couriers and health clinicians visiting patients in their own home.