The Sit and Stand Chair. A Revolutionary Advance in Adaptive Seating Systems

Abstract

A major factor governing independence for the elderly and persons with disabilities is the ability to stand from a chair. Factors such as pain, reduced joint range of motion, stiffness, and muscle weakness frequently limit the ability to stand. Sit-to-stand position is even further reduced in patients whose hands and shoulders are afflicted with rheumatoid arthritis. When achieving a sit-to-stand position in the elderly and persons with disabilities, there is considerable risk of the individual falling and sustaining bone fracture. The purposes of this scientific report are to achieve the following goals: (1) to provide a narrative discussion of the senior author's contributions to furniture manufacturing as well as his successful patent application for the SIT & STAND chair, (2) to describe the steps involved in the development of the SIT & STAND prototype, and (3) to examine the performance of the SIT & STAND chair in assisting the elderly or persons with disabilities in achieving a sit-to-stand position. The invention of the SIT & STAND chair by the senior author, Michael Galumbeck, was a culmination of his lifelong interest in adaptive seating systems. His electrically operated chair has the unique ability to assist the occupant to achieve safely a sit-to-stand position. The rear portion of his chair remains in a fixed position to support the buttocks of the user during mechanical lift. The front portion of the seat folds down incrementally as the chair rises to allow the feet of the user to be positioned in a more posterior position firmly on the floor. Using its actuator, the height that the chair rises will vary with the length of the legs of the occupant. Using the drawing program Solid Works (Solid Works, Concord, Massachusetts), drawings of the chair were made. To visualize the operation and performance of the chair, separate drawings were made in the lateral position. The prototype of the SIT & STAND chair was manufactured with an electric actuator that allows elevation of the back portion of the seat. The design of this chair ensured that there were no pinch points that could endanger the user or assistant. Its framework ensured that it was stable and did not tip over. After the prototype chair is manufactured, it is being sent to Underwriters Laboratory Inc. (Los Angeles, California) for review and certification. The performance of the SIT & STAND chair was determined in a clinical study involving seven elderly or disabled individuals who complained of difficulty in rising from a chair from a seated position. During each performance evaluation, a mechanical chest and shoulder harness attached to an overhead sling encircled the individual to ensure that he/she would not fall. In the first part of the evaluation, these individuals were asked to achieve a standing position after being seated in the SIT & STAND chair without the use of the actuator. Three individuals were unable to achieve a standing position, while four achieved this standing position with considerable difficulty and potential instability. When these participants used the SIT & STAND chair with the use of the electrical actuator, all individuals achieved a standing position without difficulty or instability. All individuals expressed disappointment that the SIT & STAND chair was not commercially available for them to purchase and use in their homes. Because the SIT & STAND chair allows the individual to achieve a standing position without assistance, the SIT & STAND chair has other potential benefits not evaluated in this study. The beneficial effects of standing have been documented by comprehensive scientific studies. These benefits include reduction of seating pressure, decreased bone demineralization, increased bladder pressure, enhanced circulatory regulation, reduction in muscular tone, decrease in upper extremity muscle stress, and participation in activities of daily living. Another irrefutable benefit of the SIT & STAND chair is that the chair eliminates the need for physical assistance from family members or health care personnel, preventing the development of disabling back injuries in personal care assistants. In addition, the SIT & STAND chair entirely removes the risk of pain or harm to the individual, which sometimes occurs with manual assist to stand, such as dislocation or fracture of frail shoulders with the under-axilla lift. Realizing the medical benefits of the SIT & STAND chair, Aetna completed a clinical policy bulletin that states that the seat lift mechanism is a medically necessary durable medical product. On the basis of this extensive product and performance evaluation, we recommend the SIT & STAND chair for the elderly as well as persons with disability to safely achieve a sit-to-stand position.