Application of Zen sitting principles to microscopic surgery seating

Abstract

This paper describes the application of an alternative seating concept for surgeons that reflects the research of Zen sitting postures, which require Zazen meditators to maintain fixed postures for long durations. The aim of this alternative approach is to provide sitters with a seat pan with sacral support 1 1 The term ‘sacral support’ seems to be commonly used in the U.S., while Japanese people customarily use ‘pelvic support’. The first known use of the term ‘pelvic support’ appeared in Yu and Keyserling (1989). Wu et al. (1998) performed an in-depth analysis of the effectiveness of pelvic support for inducing pelvic tilt. In recent years, advances in technology have enabled the direct measurement of pressures on the sacral area that are distinct from those on the pelvic area. In this article, the term ‘sacral’ is used only when the sacral area is identified by palpation. The distinction between pelvic and sacral supports is defined in Section 6.2.1 of this article in relation to Fig. 10. that provides a more even distribution of seat pressures, induces forward pelvic rotation and improves lumbar, buttock and thigh support. This approach was applied to the development of a chair for microscopic surgery. The experimental chair is a seat pan that closely matches the three-dimensional contours of the user’s buttocks. Seat comfort was evaluated by comparing both changes in pelvic tilt and seat pressure distributions using Regionally-Differentiated Pressure Maps (RDPM) with subjective ratings of surgeons while operating in prototype and conventional chairs. Findings include that the sacral support of the prototype chair prevents backward pelvic rotation, as seen in zazen (Zen sitting postures). Preliminary data suggests that the prototype provided greater sitting comfort and support for constrained operating postures than did the conventional chair. These findings support the selective application of concave-shaped seat pans that conform to users’ buttocks and reflect Zen sitting principles.