Low back load in two car driver seats

• Published in: International journal of industrial ergonomics Vol. 20; no. 3; pp. 215 - 222
• Main Authors: Udo, Hiroshi, Tajima, Takaoki, Uda, Shinichi, Yoshinaga, Fumitaka, Ishihara, Eiji, Yamamoto, Yoshihisa, Hiura, Nobuhiro, Kataoka, Akihiko, Nakai, Kuniharu, Umino, Hideki
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.1997
• Subjects: Design; Driver seat; Low back load; Lumbar support; Seat cushion; Side support; Design; Low back load; Side support; Lumbar support; Seat cushion; Driver seat
• ISSN: 0169-8141; 1872-8219
• DOI: 10.1016/S0169-8141(96)00055-8

Low back pain is a significant health problem for professional drivers. Therefore it is important to design a car driver seat with less load to reduce low back pain. The purpose of this study is to compare the low back load in a long-term driving experiment between two different types of driver seats (the new seat and the standard seat). The new seat has the following characteristics vs. the standard seat: (1) a lumbar support, (2) side supports, (3) seat is firmer at the ischial tuberosity region, but it is softer at the femoral region, (4) a head rest which is adjustable sagittally, and (5) a rubber mat under the seat. Sixty male subjects, who commuted 5 times/week for about 50 min/trip with the standard seat and complained of low back pain in driving, were selected from a group of 1600 subjects. The existing seat in their personal vehicles was replaced with the new seat for 30 subjects. For 6 months, 30 used the new seat, and the other 30 used the standard seat. Before, and 3 and 6 months after the start of the study, the low back load was estimated by lumbar examination and subjective evaluation of low back pain. At the second examination, the subjective evaluation significantly improved for the new seat (vs. the standard seat). At the third examination, the kinetic pain score in bending backward and the Lasegue test significantly improved for the new seat (vs. the standard seat). It is suggested that the low back load of the new seat was less than the standard seat. The factors of the lumbar support, the side supports, the firmer seat at the ischial tuberosity region, the adjustable head rest and the rubber mat all contributed to a reduction in low back load.