ActiGait implanted muscle stimulator improves walking for stroke
1 June 2010
Otto Bock Healthcare has launched the ActiGait implant that
aids stroke patients suffering from drop foot by electronically
stimulating leg-muscles to compensate for the lack of control of the
The ActiGait system restores a steadier and more natural walking
pattern to the wearer, meaning users can focus on their outer
environment and return to more normal daily activities.
Drop foot is the inability to raise the foot due to a weakness in
or paralysis of the dorsiflexor muscles. This condition is a
frequent result of damage to the central nervous system following a
stroke. ActiGait is implanted beneath the skin of the thigh, with
the control unit worn comfortably on a belt and is easy to use, even
for patients with impaired arm functionality.
The system is not encumbering as it is wireless with implanted
electrodes. This is in contrast to other wired devices that use
external electrodes requiring careful positioning on the surface of
the leg, a time-consuming and challenging process, often quoted as
reasons to cease using these devices.
The ActiGait implant components
ActiGait operates through different components (see image above).
Stimulation signals and energy impulses from the control unit are
sent through the skin via a lightweight antenna, worn on the thigh
to the implanted four channel cuff electrode positioned around the
common peroneal nerve, which activates the muscles of the front and
lower leg and provides a balanced dorsiflexion. A wireless heel
switch, which can be worn either with or without a shoe, registers
the lifting and placement of the foot and triggers the stimulation.
Patient studies carried out in Denmark (Journal of
Rehabilitation Medicine 40:89-91) illustrated an increase in
distance patients could walk in a four-minute period and in walking
speed over 20 metres, without the help of another person.
Furthermore, qualitative responses highlighted improvement in
confidence with less fear of falling, promoting the long-term
potential to provide a positive effect on personal well-being,
safety and performance.
Dr Salim Ghoussayni, Business Development Manager for
Neurostimulation at Otto Bock Healthcare states, “Each year
approximately 110,000 people in England alone suffer from a stroke,
making it the single most common cause of severe disability. Around
300,000 people are living with moderate to severe disabilities as a
result of stroke. Feedback from patient studies in Europe has
revealed that ActiGait enables stroke patients to walk longer
distances at an increased speed and with improved confidence. As it
is implantable, it also offers a more cosmetic and practical
user-friendly alternative for individuals who cannot use a surface
device due to skin reactions, for example.”