Prosthetic Components & Design - feet Flashcards
what foot goes with K1
SACH foot
what foot goes with K2
single axis or multi-axial
what foot goes with K3
multi-axial
what foot goes with K4
hydraulic ankle, multiaxial, crossover
SACH foot
- single axis, cushioned heel
- stiff, rigid = stable
- limited energy return
- wood block, rubber heel on top
single axis
- has an articulating joint that provides PF and DF
- can PF quickly, providing foot flat at initial contact
- increases user confidence
- good for TFA
multiaxial
- allows for PF, DF, inversion and eversion
- split toe designs can allows for uneven terrain
- very functional, good energy return
- spring = PF, DF
- split = inv., ev
keel
- supportive structure of the prosthetic foot that provides stability to the user
- rigid, flexible or dynamic
- length is important to gait
length of keel is important to gait, and has upstrem effects:
- toe lever
- heel rise/toe break
- knee flexion/stability
types of prosthetic knees
single axis & polycentric
manual locking
pneumatic & hydraulic
microprocessor
what is the goal of prosthetic knees
stance and swing phase control
single axis and polycentric
- most basic knee type
- provide for stance control through alignment, encouraging the GRFV to be anterior to the prosthetic knee to ensure stability
what does single axis and polycentric require
does not requre any additional components to maintain extension during stance, but does require active hip extension
what phase of gait does single axis and polycentric not provide for
swing phase control
manual locking
- most stable stance control knee
- does not allow for knee flexion during swing phase
- lock must be open for patient to sit
- K0-K1
what strength does manual locking knees require
- hip ext strength to get knee ext
hydraulic & pneumatic knees
- provide for swing phase control by dynamically adjusting swing speed to users gait speed
- can have stance phase control built in
- uses friction to control swing speed
- K3
benefits of hydraulic & pneumatic knees
- control on uneven surfaces
- variable cadence and gait speed
- mimics normal gait
microprocessor knees
- provides stance and swing phase control
- sensors measure joint angles, cadence, etc. to provide the user with a stable knee that is responsive
- K3
benefits of microprocessor knees
- stumble recovery
- stairs
- power
