The effect of cushion properties on skin temperature and humidity at the body-support interface

Abstract

The purpose of this study is to explore the effects of various cushions on skin temperature and moisture at the body-seat interface during a 2-hour period of continuous sitting. Seventy-eight participants were randomly assigned to sit on one of the three types of wheelchair cushions for unrelieved sitting for over 2 hours. Skin temperature and relative humidity (RH) were measured under the subjects' ischial tuberosities and thighs bilaterally with digital temperature and humidity sensors. Data were collected before sitting and at 15-minute intervals thereafter. Participants sitting on foam-fluid hybrid cushions showed significantly lower skin temperatures than those sitting on air-filled and foam cushions (p < 0.05), but RH did not differ significantly among the cushions (p = 0.97). The three cushions produced a similar increasing trend in RH over time and RH reached a plateau during the 2-hour sitting period. To select the appropriate wheelchair cushion, the microclimate (heat and moisture control) between the body-seat interface should be considered as well as pressure distribution. In comparison with foam-fluid hybrid cushions, the air-filled rubber and foam cushions tended to increase skin temperature by several degrees after prolonged sitting. However, cushion materials did not have significant differences in moisture accumulations.

Review of Measuring Microenvironmental Changes at the Body–Seat Interface and the Relationship between Object Measurement and Subjective Evaluation

“…As result, a more complete thermal mapping of the contact surface could be constructed by employing imaging algorithms [28]. In order to explore the microclimatic characteristics at the same locations, use of integrated temperature-humidity-sensors has also been reported in several publications [11,31,[35][36][37].…”

“…This indicates that it is critical to take thermal properties of different materials into consideration when manufacturing cushions. Furthermore, thermal outcomes at the contact surface can be influenced by several components including configuration (e.g., foam-fluid hybrid) [31], ventilation (e.g., strap-based) [10] and structure (e.g., honeycomb-structured) [30]. Consequently, it is crucial to study thermal management capacities of different cushions, especially for prolonged sitting usages (e.g., wheelchair cushion).…”

“…In other words, there is a transient impulse response induced during the initial process of sitting down. Unlike the temperature showing significant difference among different materials, relative humidity had no consistent performance which indicates one should be cautious when using relative humidity as a physical factor to study at enclosed interfaces, especially where temperature changes are occurring [13,31]. The combination of relative humidity sensor and temperature sensor on the same structure might help to reduce this artifact in the future and make the relative humidity changes more consistent and reliable.…”

Evaluation of postural systems of the pelvis in a person with Limb-Girdle Muscular Dystrophy: results of the analysis of three cushions in the promotion of dynamic balance

“…Na sua construção podemos encontrar diversos materiais mas os mais comuns são gel, espuma, ar e fluído (individualmente ou combinados) (Hsu et al, 2018). As almofadas que contêm gel são constituídas por uma bolsa individual, que se encontra fixa a uma base de espuma, ajustando-se à pressão exercida pelo corpo.…”

Study of castor oil‐based auxetic polyurethane foams for cushioning applications

“…If pressure ulcers are left untreated, they can be life‐threatening. Soft tissue protection over the skin area is necessary particularly for individuals who are bedridden and/or chair‐bound 1 …”