A Pilot Study to Evaluate Differences in Spinal Angles During a Seated Computer Task Compared With a Self-Selected Optimal Sitting Posture

Conflicts of interest: No conflicts of interest Sources of funding: No funding obtained Background Low back pain is the leading cause of years lived with disability worldwide and consequently it is the most common condition treated by physiotherapists in an out-patient setting. Physiotherapists also have a role to play in preventing spinal pain by providing ergonomic education. Purpose of Study To compare spinal angles whilst conducting a seated typing task with a self-selected optimal posture. Methods Cross-sectional pilot study. Twenty asymptomatic participants (9 male, 11 female, aged 19 to 23 years) adopted their normal sitting working posture using a laptop to conduct a typing task; they were then asked to adopt what they considered to be their best sitting posture. Retroreflective markers were attached to: L4, ASIS, PSIS, T12, C7, tragus and canthus. Spinal (neck, thoracic, lumbar and pelvic) angles were established via digital photographs using a bespoke MATLAB programme (MathWorks). Statistical analysis (Wilcoxon signed ranks tests) was conducted to determine between condition differences. Results No statistically significant results were observed between conditions for pelvic angles (p>0.05), however statistically significant differences (p<0.05) were observed for lumbar, thoracic and neck angles. In all cases participants adopted more ‘upright’ optimal postures. Conclusion The results suggest that a self-selected optimal posture varies significantly with a computer working posture for lumbar, thoracic and neck angles. Whilst pelvic angles were not significantly different between conditions, descriptive analysis demonstrated a more flexed position for all angles during the working posture. Whilst an optimal posture remains debatable, these differences highlight the need to identify interventions to address differences between working and optimal postures.