For upper limb (hand/arm) amputations, there are both cosmetic and functional prosthetic options. Functional prostheses can be made with mechanical systems as well as electronic systems. Some electronic arm prostheses are based on the myoelectric control principle, as in myoelectric hand applications, which are operated by electrical signals picked up from the muscles. These fittings are planned in line with a specialist physician's prescription and medical report.
How myoelectric control works
- Electrodes placed on the skin surface detect small-scale electrical signals in muscle cells.
- The electrical activity generated when the muscle contracts is transmitted to a measuring device.
- The signal level shown on the measuring device's display helps determine the appropriate electrode position.
- Prostheses of this type usually run on an integrated battery; details of the system as a whole are covered under myoelectric arm prostheses.
Determining electrode position
The assessment process is carried out by the relevant healthcare professional:
- Muscle motor areas in the residual limb are identified by manual examination and small test movements.
- Electrodes are placed on the areas where the clearest signal is obtained.
- The measuring device is switched on, signal acquisition is monitored and the necessary adjustments are made.
- Suitable electrode positions are recorded and used as a reference before the definitive prosthesis is assembled.
Rehabilitation with EMG biofeedback
Myoelectric measuring devices can be used not only to determine electrode position but also in the neuromuscular rehabilitation process:
- Real-time EMG feedback (biofeedback) may help the person control their muscles more consciously.
- Distinguishing individual muscle activations may help develop functional movements, as with myoelectrically controlled arm prostheses at the above-elbow level.
These processes may be used during the prosthetic adaptation stage to increase awareness of muscle control and to support prosthetic comfort. Assessments and fittings are carried out in a center setting under the guidance of the relevant specialist physician.
This content is for informational purposes only; you should consult your physician for diagnosis and treatment.
