A single step process to design a custom mattress that relieves trunk shear forces

Back pain is a common complaint that may result from the use of an inappropriate mattress. It can be minimized by using a well suited mattress. This paper presents a method for designing a custom foam mattress in an attempt to reduce back pain for the lateral lying position. Body three-dimensional profile and its mass distribution are both estimated by a simple photographic method. Finite element models are established and precalculated to characterize and predict the interaction between the body and the mattress surface. The process is based on two design performance criteria: a spine curvature in the frontal plane similar to a standing one and a given load distribution along the mattress. The process is validated with three mattresses customized to three individuals. Results show a good fit with numerical predictions according to the two performance design criteria.