Prosthetic Components & Technology Flashcards
7 cards from real CPT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Prosthetic Components & Technology flashcards as text
Microprocessor-controlled prosthetic knees (MPKs) use onboard sensors primarily to assess which variables in real time?
Answer: Angular velocity, acceleration, and load data to modulate hydraulic resistance
MPKs use gyroscopes, accelerometers, and load cells to continuously assess limb kinematics, then adjust hydraulic or pneumatic resistance to optimize gait.
What type of wrist unit allows a transradial prosthesis user to pre-position the terminal device in multiple planes of rotation?
Answer: Flexion-rotation wrist unit (flexion/extension and rotation)
A flexion-rotation wrist unit provides both wrist flexion/extension and forearm rotation positioning, enabling the user to pre-set the terminal device for varied tasks.
Which suspension method for a transtibial prosthesis relies on a urethane or silicone liner rolled onto the residual limb, with a locking pin that engages a clutch mechanism in the socket?
Answer: Pin/lock (lanyard) suspension
Pin/lock suspension uses a distal locking pin on the liner that clicks into a clutch or shuttle lock built into the distal socket, providing reliable mechanical suspension.
Elevated vacuum suspension (EVS) systems improve prosthetic suspension and residual limb health primarily by:
Answer: Maintaining negative pressure within the socket to reduce volume fluctuation and pistoning
EVS actively evacuates air from the socket interface, creating consistent negative pressure that stabilizes residual limb volume, reduces pistoning, and improves proprioception.
A myoelectric prosthetic hand uses surface electromyography (sEMG) signals from residual limb muscles to control the hand. Which muscle pair is most commonly used for transradial myoelectric control?
Answer: Wrist flexors and wrist extensors
The wrist flexors and wrist extensors of the residual forearm are the primary electrode sites for transradial myoelectric control, as they retain voluntary muscle function distal to the amputation.
In lower-limb prosthetics, a dynamic response (energy-return) prosthetic foot's carbon fiber keel primarily stores energy during which phase of gait?
Answer: Initial contact and loading response (heel strike)
The carbon fiber keel deflects during loading response (heel strike to mid-stance), storing elastic energy that is subsequently released at toe-off to assist propulsion.
Which feature distinguishes a multi-axial prosthetic foot from a single-axis foot?
Answer: It provides motion in the frontal plane (inversion/eversion) in addition to sagittal plane movement
Multi-axial feet allow inversion/eversion and transverse rotation in addition to plantarflexion/dorsiflexion, better accommodating uneven terrain and reducing socket stress.