Scelta Cookie
Newsletter
Register for the newsletter. We'll send you news, information, updates and insights. Rimani aggiornato e iscriviti alla newsletter
Sign up here
ItalianoEnglish

Myoelectric Prostheses

Myoelectric Prostheses
A myoelectrically controlled prosthesis uses muscle contractions as a signal to activate the prosthesis. It functions by detecting electrical activity from select residual limb muscles, with surface electrodes used to control electric motors. They have only been recently introduced, as the first prosthesis in Italy can be traced back to 1965. They represent the state of the art in technology and in this sector a lot of progress is taking place thanks to electronic and mechanics development.

Currently elbow flexion/extension, wrist supination/pronation (rotation) or hand opening/closing of the fingers can be controlled thanks to 3 direct-current motors

A myoelectric prosthesis uses electromyography signals or potentials from voluntarily contracted muscles within a person's residual limb on the surface of the skin to control the movements of the . It functions by detecting electrical activity from select residual limb muscles, with surface electrodes used to control electric motors
This signal detected on the skin has an excursion which ranges from tens of microvolts to tens of microvolts, and is first amplified and then elaborated by a control unit which defines which movement to make based on an algorithm.
It’s necessary to point out the difficulty in elaborating the signal received, both in terms of low value and in terms of band of frequency the information contents is concentrated in; this band of frequency, which is concentrated below 1KHz, is characterized by the presence of interferences, frequently higher than the electromyography signal; this leads to having to use both analogical and digital filtering.

For example, a patient contracts muscles on which an electrode is placed in order to open their hand. The electrode detects an activity and informs the central unit what sort of movement the patient wants to make. 2 electrodes which determine the opening and the closing of the electric powered prosthetic hand are used to make it move. A necessary condition is that the signal is broad enough to be detected by the sensors, and that the patient can create them independently.

It all works out correctly if the muscles are activated one at a time, otherwise the control system will have to execute 2 contrasting orders thus not allowing the prosthesis to work properly.
If the forearm extension muscles are being used to open a prosthetic hand, and the flexion muscles are used to close it, such movements are quite simple to learn as they are quite similar to a natural limb movement.

The higher the level of amputation, the more complicated the motor scheme applied onto the muscle will be to activate the prosthesis. 
A more complicated prosthesis example with a 6 –function activity: elbow flexion/extension, wrist supination/pronation (rotation) or hand opening/closing of the fingers; in this case 6 muscles need to be separately controlled by the patient. Experience has taught Centro Protesi how transhumeral amputees, on whom a hand-elbow and wrist prosthesis has to be applied, can be able to distinguish only up to 4 separate signals.

Myoelectrical prostheses may be applied starting from wrist amputation.

Today also children from their very first years of life can apply myoelectrical prostheses due to its drastic  weight reduction.
p>

Slogan

After the verb "to love" the verb "to help" is the most beautiful in the world

Our Numbers

Experience (year)
20
We helped (people)
12312
.. of which children
8618

Opening time


We are in MARNATE (VA), in via LUIGI POMINI 92
Opening time
From monday to friday (saturday we re closed)
from 9:00 to 12:30
and from 14:00 to 18:30

For special request, we receive only by appointement.

Centro Ortopedico Essedi
VIA POMINI 92, 21050 MARNATE (VA) - VAT: 02521320123
Telephone: 0331 502909
Fax: 0331 483949
info@centroessedi.it

Brochure Essedi