Medical Aids and Devices
Prostheses (plural)
Prosthesis
• An artificial extension that replaces a
missing body part
• Typically used to replace a missing body
part or enhance a defective body part
– Lost by injury (trauma)
– Missing from birth (congenital)
• Common uses: artificial heart valves
Artificial organs
• Man-made device that is implanted into a
human to replace a natural organ to
restore a specific function
– Not external (ex. dialysis machine) but
internal
An extremely expensive process,
used for:
• Life support to prevent imminent death
while awaiting a transplant (e.g. artificial
heart)
• Dramatic improvement of the patient's
ability for self care (e.g. artificial limb)
• Improvement of the patient's ability to
interact socially (e.g. cochlear implant)
• Cosmetic restoration after cancer surgery
or accident
Examples of prostheses
• Artificial heart valves
Artificial heart
• dentures
• Artificial eyes
• Artificial valves
– Especially at ends of stomach, to help with
function of sphincters
– Used for esophageal cancer, reflux disease
• Artificial ear
– Cochlear implants to help with hearing or
cosmetic repair
Prosthetic enhancement
• 2008, Oscar Pistorius
was disqualified as an
olympic runner due to
the “unfair mechanical
advantage” of his
prosthesis
• Mechanical parts could soon surpass
human equivalents in their efficiency…
• Part of biomechatronics: the science of
using mechanical devices with human
muscle, skeleton, and nervous systems to
assist or enhance motor control lost by
trauma, disease, or defect
• Biosensors detect what the user wants
and relay that information through the
user’s nervous/skeletal system to a
controller
• The controller located inside the device
will than control the device, sensing the
limb’s position and force
Amanda Kitts is learning
to use her new limb…
• Claudia Mitchell, former Marine and amputee, has tested
a prosthetic arm developed by Dr. Todd Kuiken at the
Rehabilitation Institute of Chicago. A plastic surgeon, Dr.
Gregory Dumainian at Northwestern Memorial Hospital in
Chicago re-directed the nerves that control her missing arm to
her chest. The nerves re-grew close to the skin of her chest.
Tiny electrodes on her skin pick up the electrical activity of
these nerves and send signals to the motors in the arm. She is
able to control the arm's movements by thinking about it. As of
now, the prosthetic arm is not truly biomechatronic in that
signals only go one way, from Claudia to the arm. Dr. Kuiken is
working on the next step of having the arm provide feedback to
her, including sensations such as pain and pressure.
Greg Gadson lost both his legs in a
roadside bomb in Iraq and is now
“meshing my 43-year-old body with a
machine”
Pacemakers
• Brain pacemaker
– Sends electrical impulses to brain to relieve
depression, epilepsy, tremors
• Artificial pacemaker
– Electronic device that helps to keep the heart
contractions regular
The Future
Natural-feeling neuroprostheses
Re-training the brain to control a
prosthesis
Artificial eyes
Using circuits to translate messages
Using solar panels….