Introduction to Passive Prostheses
by Amber Henson, on Dec 7, 2020
The definition of a passive prosthesis is a prosthetic device that does not move on its own. It is neither body-powered nor is it myoelectrically powered. Some passive prostheses can still be moved, but they must be moved by the user's other hand. Others do not move and are used both for looks and to protect the user's residual limb.
Diana’s right arm is a passive prosthetic device - she is an above-elbow amputee
Passive prostheses are often designed to look like a natural arm, hand and fingers. These prostheses are lightweight and while they do not have active movement, they may improve a person’s function by providing a surface for stabilizing or carrying objects.
Passive prostheses may be covered with high-definition silicone that is custom painted to closely resemble the person’s sound arm, hand and fingers, or a more basic production glove.
Multi-positional joints are sometimes combined with a passive prosthesis to provide the option of being able to position the shoulder, elbow, wrist or finger joints to improve a person’s function. For example, using the sound hand, a multi-positional shoulder, elbow or wrist joint can be positioned at a specific angle, making it easier to hold or carry something. Multi-positional finger joints can be moved into position to allow a high-definition restoration to grasp small objects.
However, you don’t need to have a silicone cover if you choose a passive prosthetic. Mark Betters, seen in the GIF below, uses passive Point Design digits. They look robotic, but because Mark has to use his sound hand to manipulate them, that means they are passive as opposed to body-powered (able to move based on the movement of the residual limb) or myoelectric (where the movement is controlled using muscle impulses from the residual limb). Mark likes these ratcheting digits because they are rugged and able to handle a lot of weight – very important features for his work in the construction industry.
If you are interested in how a passive prosthetic might help you regain function or help you feel more balanced, please contact us. If you are the owner of a passive prosthetic device and would like to share with others how you like it, please comment below!
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