Toronto Rehab scientists develop SoleSensor to help older people stay on their feet

In an aging society, falling is a growing problem. Just one bad fall can mark the start of a downward spiral in an older person's health and quality of life. The cost of treating falls also puts a heavy burden on the health care system. Toronto Rehab scientists have developed a simple footwear insole called SoleSensor(TM), which has proven to improve balance and prevent falls.

"Pressure sensation from the soles of the feet plays an important role in controlling several key aspects of balancing reactions," says Stephen Perry, a Toronto Rehab adjunct scientist and associate professor of kinesiology and physical education at Wilfrid Laurier University.

Over time sensation in the soles of our feet is dulled as skin hardens, calluses develop, and tiny sensors in the skin decrease in number and sensitivity. In addition, nerve impulses to the central nervous system slow down with age.

SoleSensor has a raised ridge that surrounds the perimeter of the foot, stopping just short of the large toe. This ridge is designed to enhance the sole's sensory perception by stimulating tiny sensors located in the outer edges of the sole. SoleSensor enhances balance by heightening foot-sole sensation.

"SoleSensor increases the sensory information your foot sends to your brain with every step you take," explains Perry. "If you're swaying back and forth, the raised edge will apply pressure to the side of your foot, telling you subconsciously that you're falling. You can then adjust your body movements and hopefully prevent a fall."

"Roughly one in three people aged 65 or older falls at least once a year. Falls result in almost 95 per cent of hip fractures in older people and 20 per cent die within a year of the fracture," says Geoff Fernie, Toronto Rehab's vice president of research and co-inventor of the insole. "Fall-related injuries in Canada have been estimated to cost the economy $2.8 billion a year."

"SoleSensor is a simple, cost-efficient way to help older people stay on their feet. The savings to the health care system are considerable if the device can reduce visits to emergency rooms, surgical procedures, and hospital stays," says Fernie.

Many older people who survive a fall never fully recover. Even one bad fall can have long-term consequences, including chronic pain from the injury, a disability that reduces independence, or constant fear of another fall. All of these consequences discourage a healthy active lifestyle.

"Older people fear falling, so they stay indoors," says Perry. "They don't exercise, so they lose functionality. It's a cycle of decline. Giving them more confidence - so they can go out more often for fresh air or to run errands - might be just enough to increase their quality of life."

Perry and colleagues tested SoleSensor over a 12-week period in winter. Twenty healthy older adults who wore the sole had half the number of falls compared to 20 who wore only conventional or flat insoles. Their findings were reported in the June 2008 issue of the Journal of Gerontology: Medical Sciences.

Currently, SoleSensor is being tested on people with Parkinson's disease. Parkinson's is a progressive disease of the central nervous system that affects 100,000 Canadians and 6.3 million people worldwide. The disease generally affects people 60 and over. In Perry's study, 40 people with Parkinson's disease and 40 who do not have the disease, were tested walking 20 feet at a time while wearing, alternately, a ribbed insole (SoleSensor) and flat insole. As reported in the May 2009 issue of Parkinsonism and Related Disorders, Parkinson's participants showed significant improvements in their walking stability and a normalizing of their walking patterns. Perry hopes that SoleSensor will ultimately reduce the likelihood of falling in people with Parkinson's disease.