A revolution in seating.

Nursing home seating for residents is on the edge of a breakthrough brought about by the innovative work of biomechanical and biomedical engineers. Using the results of the ongoing revolution in computers and computing power, they are, in the words of Clifford Gross, PhD, founder and CEO of Biomechanics Corporation of America (BCA), "turning the art of seating design into a science."

Until recently, state-of-the-art in geriatric-chair, recliner and wheelchair design has meant developing cushioning and posturing appliances to make the patient comfortable. Chairs were designed to fit the largest size potential users and modified on-site with pillows, cushions, foam pads, gel seats and, most recently, active pneumatic technology. This has its obvious limits.

"Most geriatric chairs were designed for someone in the 6'4" to 6'6", 280-pound range," says Stephen Sprigle, PhD, biomedical engineer at the Center for Assistive Technology, State University of New York at Buffalo, and an expert on therapeutic seating design. "I'm 6'2", and I can't sit comfortably in them."

Sprigle acknowledges many recent advances in seating and positioning, but, he says, they've encountered a roadblock in nursing homes: "Their funding mechanisms haven't advanced to keep up with developments in equipment. These new seating systems have been developed for use in more intensive rehabilitation environments and haven't reached long-term care yet, largely because of high cost and reimbursement difficulties."

Sprigle says he sees this changing. "A higher level of seating care is going to become available because there is a change in how therapy services are being provided to nursing homes. As nursing homes contract for physical and occupational therapy, they are being exposed to newer technology. And subacute care is educating staff and creating advocates for more comprehensive seating solutions." He also sees the use of electro-mechanical pressure-management beds in nursing homes as a "door opener" for similar active seating technology.

BCA is a major developer of user-responsive active technology as it applies to seating, with one laboratory devoted entirely to seat pressure and comfort. BCA licenses its "intelligent surface" technology to companies for use in their products.

Intelligent surface technology, according to BCA, allows surfaces which come in contact with the body to automatically change shape to facilitate comfort, fit, and safety. It first measures load distribution on the body, then calculates the most comfortable surface shape, and changes the shape of the surface to optimize comfort. BCA sees its technology being incorporated into such products as automobile, office and truck seats, regular and hospital beds, athletic shoes, wheelchairs, recliners, and geriatic chairs. With 23 patents applied for and eight awarded, BCA lays claim to being a leading research center in ergonomics.

"Ergonomics," says Gross, "is the science of adapting products to fit people, not the other way around. We have been able, for the first time, to measure what a person subjectively feels as comfort when he sits. We built the first sensor mats -- paper-thin force sensing surfaces that allow us to measure the pressure at the interface of seat and person -- and then we quantified that data as a formula for load distribution, using over 3,000 seating measurements of various body types in differing sitting situations."

In early October, BCA announced licensing of its surface-sensing technology to Lumex, Inc. for use in medical recliners and rockers and operating room tables. Lumex, a manufacturer of medical and fitness equipment, is planning to introduce "first intelligent medical recliner" by the second quarter of 1995.

The recliner employs seven separate, active air bladders supporting the neck, lower back, buttocks and thighs. Using BCA's sensor technology for force measurement and micro-processors to control pressure in each of the bladders, the chair adjusts automatically to an occupant and to the occupant's changes in position. It takes about 30 seconds to inflate the bladders to the exact conformations of an occupant. After a change of position, a touch of a switch reconforms the bladders.

BCA's intelligent surface technology promises to offer major increases both in comfort and quality of life for patients who sit for long periods of time -- if, as its developers believe, it is able to bring two major aspects of seating into balance:

"There is a dichotomy in seating," explains Sprigle," involving two concepts that are always in opposition -- support and mobility. If you are completely supported when seated, you are not very mobile. You can't over-support patients in a seated posture and expect them to be very active." By optimizing support and then allowing that support to change as a patient moves in a chair, intelligent surface technology is bringing new comfort and safety to long-duration seating.