Background: Age-related loss of foot-sole cutaneous sensation is very common and is associated with impaired balance control. This study investigated the effect of a balance-enhancing insole (designed to facilitate foot-sole sensation) on lateral gait stability and evaluated its effectiveness in daily life.
Methods: Forty community-dwelling older adults (age 65-75) with moderate loss of foot-sole sensation (unrelated to neuropathy) were fitted with the same model of walking shoes. Half of the participants were assigned, at random, to wear the shoes with a facilitatory insole for 12 weeks; the other participants wore a conventional insole. A gait perturbation protocol, simulating uneven terrain, was performed at baseline and after wearing the assigned insoles for 12 weeks. Participants were tested with both types of insoles during each gait-testing session and sent in weekly postcards with information pertaining to insole comfort, hours of wear, and falls.
Results: The facilitatory insole improved lateral stability during gait, and this benefit did not habituate after 12 weeks of wearing the insole in daily life. Nine participants who wore conventional insoles experienced one or more falls, whereas only five of the facilitatory group fell. Although there were initial reports of mild discomfort in 10 cases, all but one participant tolerated the facilitatory insole, and most indicated that they would like to continue wearing the insole on a long-term basis.
Conclusions: A relatively simple change in insole design can help to counter effects of age-related (non-neuropathic) decline in foot-sole sensitivity, and is a viable intervention to enhance balance control.