An objective evaluation of patient seating solutions for the elderly population
Significant improvements in healthcare, nutrition, and technology, have resulted in a larger elderly population and an increased demand for healthcare services appropriate for older patients. The elderly are far more prone to get sick and are more susceptible to injuries. One of the most serious and widely discussed injuries, that threatens older people, is falling. In hospital rooms, the patient chair is one of the locations where falls occur. It is also a critical point in patients’ transition to independence and functional status. Therefore, despite the fall risks, patients are encouraged to leave their bed, move around their room, and sit in their chair to accelerate the healing process. The ultimate purpose of this study was to decrease the risk of fall among the elderly patients by making it easier for them to sit in and stand from their chair. The study examined the impact of manipulating the horizontal and vertical position of armrests in a test chair on physical effort during Stand-to-Sit-to-Stand (St-Si-St) transitions among fifteen elderly women whose heights and weights were within the 15th and 85th percentile of elderly American women. Three main research questions were posed: 1) Do armrest height and distance have a significant effect on physical effort when being used by the elderly for sitting and standing? 2) How does the pattern of physical effort change as armrest height and distance change? 3) What are the optimum levels of armrest height and distance to decrease the required effort for sitting and standing? Electrical activity of skeletal muscles in the dominant arm and leg, exerted force on the armrest by the dominant arm, and time to complete the transition were measured as indicators of physical effort in a series of trials. ANOVA and Polynomial Regression were used as the main statistical procedures for data analysis. Study findings showed that changing armrest height and distance causes a change in physical effort that follows opposite patterns in arms and legs. These identified patterns are almost always nonlinear and can be described by cubic and quadratic relationships. It was also found that the optimum levels of armrest height and distance might be higher and wider than those already in the market. Armrests with height of 11" and internal distance of 26.5" are shown to be easier for the elderly to sit in and stand from the chair. The results confirmed the validity of the applied techniques for use in future studies in design-related fields. Further examination of patient chairs with higher and farther apart armrests, comparing with available chairs in the market, are recommended based on the results to identify the benefits for real patients, and also to balance the sitting needs of bariatric and non-bariatric patients.