Terminal devices and wrist units Flashcards Preview

Prosthetics And Orthotics > Terminal devices and wrist units > Flashcards

Flashcards in Terminal devices and wrist units Deck (16)
Loading flashcards...

Main difference between myoelectric and microswitch-controlled externally powered terminal device

Myoelectric uses surface electrodes on muscles of residual limb to activate terminal device.
Microswitch uses a button or switch to activate terminal device.


What determines prehensile force of the voluntary opening terminal device?

Number and type of rubber bands/springs


Which body-powered terminal device is more physiologic

Voluntary closing terminal device


What additional feature to a wrist unit should be considered for a bilateral UE amputee?

A wrist flexion unit to help with ADLs


What is the advantage of a locking wrist unit?

Prevents accidental rotation of the wrist when carrying something


What is a combination wrist flexion unit

Combines locking and friction types of wrist units to allow locking in wrist flexion


Three types of terminal devices

1. Passive
2. Body-powered
3. Externally powered


What determines prehensile force of the voluntary closing terminal device?

Strength of the individual


2 main types of wrist units

1. Friction wrist unit
2. Locking wrist unit


Most common type of body-powered terminal device

Voluntary opening terminal device


What is the main disadvantage of a voluntary closing terminal device?

User has to maintain constant pull on harness for prolonged prehension


Is the rotation function of a wrist unit passive or active?

Passive - so it is rotated by the user's other hand or by pushing it against something


2 types of body powered terminal devices

Voluntary opening or voluntary closing


What is the purpose of a passive terminal device

Cosmetic purpose. No function


What is the purpose of a wrist unit?

Provides pronation and supination of the hand


What is the main difference between a voluntary opening and a voluntary closing terminal device

Voluntary opening = device maintained in closed position and user has to open it.
Voluntary closing = device maintained in open position and user has to close it.