Sitting biomechanics, part II: Optimal car driver's seat and optimal driver's spinal model

Background: Driving has been associated with signs and symptoms caused by v ibrations. Sitting causes the pelvis to rotate backwards and the lumbar lor dosis to reduce. Lumbar support and armrests reduce disc pressure and elect romyographically recorded values. However, the ideal driver's seat and an o ptimal seated spinal model have not been described. Objective: To determine an optimal automobile seat and an ideal spinal mode l of a driver. Data Sources: Information was obtained from peer-reviewed scientific journa ls and texts, automotive engineering reports, and the National Library of M edicine. Conclusion: Driving predisposes vehicle operators to low-back pain and dege neration. The optimal seat would have an adjustable seat back incline of 10 0 degrees from horizontal, a changeable depth of seat back to front edge of seat bottom, adjustable height, an adjustable seat bottom incline, firm (d ense) foam in the seat bottom cushion, horizontally and vertically adjustab le lumbar support. adjustable bilateral arm rests, adjustable head restrain t with lordosis pad, seat shock absorbers to dampen frequencies in the 1 to 20 Hz range, and linear front-back travel of the seat enabling drivers of all sizes to reach the pedals. The lumbar support should be pulsating in de pth to reduce static load. The seat back should be damped to reduce rebound ing of the torso in rear-end impacts. The optimal driver's spinal model wou ld be the average Harrison model in a 10 degrees posterior inclining seat b ack angle.