January 24, 2006

Vibrating shoes aid stroke and diabetic patients

By Anne Harding

NEW YORK (Reuters Health) - Vibrating insoles can improve
balance in patients with stroke or diabetic neuropathy, a
common nerve problem that affects sensation in the feet and
elsewhere, Boston researchers report.

The vibration, adjusted to a sub-sensory level, appears to
"tickle" neurons, making them more sensitive to stimuli that
are present during standing, Dr. James J. Collins of Boston
University, the study's lead author, told Reuters Health.

Collins and his team had previously shown that sub-sensory
mechanical noise delivered to the feet via the insoles could
help people maintain better balance.

In the current study, published in the Annals of Neurology,
the researchers tested the effects of the vibrating insoles on
sway parameters in 15 patients with diabetic neuropathy and 15
patients with stroke. Patients stood on the insoles, which
contained two vibrating elements on each forefoot and one on
each heel.

Data from a previous study of the insoles in 12 healthy
elderly patients was included for comparison.

The researchers looked at five traditional sway parameters
and three derived from random-walk analysis. All were reduced
significantly with the noise application in all of the
patients, the researchers found. And the greater a patient's
baseline level of postural sway, the more balance control
improved with noise input.

Additional research is needed to investigate how the
technology may benefit patients with stroke affecting different
parts of the brain, for example the right versus the left side
of the brain, the researchers add.

"The main thing that we're focusing on now is testing
whether the insoles provide benefit in dynamic activity such as
walking," Collins said. He and his colleagues have completed
prototypes of insoles and shoes incorporating the vibrating
elements, and are planning studies to test them as patients
walk, climb stairs and negotiate other activities of daily

His team also plans to investigate whether the vibrating
insoles can help Parkinson's disease patients and patients with
multiple sclerosis.

SOURCE: Annals of Neurology, January 2006.