Prosthetic Components Flashcards
define keel
supportive structure of the prosthetic foot that provides stability to the user
*essentially the new amputee’s foot length
how is the length of the keel impactful on upstream structures?
- larger toe lever or longer keel makes it difficult for user to initate gait
- heel rise/toe break
- the position of the keel relative to the socket can impact knee flexion and stability
define toe lever
the distance from the center of the socket to the end of the keel
how does the length of the keel influence gait?
- too short → leads to knee instability in late mid stance
- too long → like clown shoes
- difficult to progress over foot in midstance and flex knee during late stance
- pts may have trouble clearing foot or catching toe
List several different types of prosthetic knees
- single axis
- polycentric
- manual locking
- pneumatic
- hydraulic
- microprocessor
prosthetic knees can influence gait by offering _________ or _________. Some even offer both of these
stance phase control
swing phase control
how can a prosthetic knee offer stance phase control?
it keeps the knee from buckling as you progress onto the foot
how can a prosthetic knee offer swing phase control?
it will control the speed at which the pylon/everything below the knee swing through during swing phase of gait
In order to promote knee stability, the GRFV must be _______ to the knee
anterior
which prosthetic knees only provide stance control?
single axis and polycentric
via alignment they promote the GRFV to be anterior to the prosthetic knee to ensure stability during stance
most basic knee types (some can provide swing phase control)
what is the benefit of a manual locking knee?
most stable stance control knee
doesn’t allow for knee flexion during swing phase
lock must be open for pt to sit
how do hydrualic and pneuamtic knees provide swing phase control?
they dynamically adjust swing speed to the user’s gait speed by friction
List several benefits to swing phase control offered by hydraulic and pneumatic knees
- control on uneven surfaces
- variable cadence and gait speed
- mimics normal gait
- some can build in stance phase control as well by increasing the friction in the cylinder
what does a microprocessor knee provide and how does it accomplish those things?
provides both stance and swing phase control
sensors measure joint angles, cadence, etc. to provide the user with a stable knee that is responsive
what are the benefits of a microprocessor knee?
- stumble recovery
- stairs
- power