Prosthetic Feet Flashcards
What is happening to the foot in the early stance of gait
Human foot is flexible and it accommodates to uneven terrain and maintains balance
What is happening to the foot in the end of stance of gait
Human foot converts to a rigid lever arm for push off at preswing
What are 2 functional tasks that occur in early stance from initial contact to loading response
- Shock absorption-knee flexion moment
2. Transition to foot flat position: GRF is posterior to ankle creating a PF moment driving the foot to the floor
How does the prosthetic foot simulate the muscle activity that is occuring during midstance of gait
Through rigid/semi-rigid or flexible keel foot
What is a keel
The center line of the foot
True or False:
We want to decrease the amount of force placed on the sound side foot in patients with compromised vascular and neurologic systems
True
What are the 4 categories of prosthetic feet
- Non-articulating
- Articulating
- Elastic keel
- Dynamic response
What is an example of a non-articulation prosthetic foot
SACH (solid ankle cushioned heel)
What is an example of an articulating prosthetic foot
- Single axis
2. Multiaxial
What is an example of an elastic keel prosthetic foot
- SAFE (solid ankle flexible exoskeleton
2. STEN (stored energy)
What is an example of a dynamic response prosthetic foot
- Seattle
- Flex foot
- Springlite
4 Pathfinder
What motions occur with a SACH foot
PF and DF only
When is the keel active in a SACH foot
Push-off
When is the heal active in a SACH foot
Heel strike
What is the keel made of
Wood or plastic
Why does the keel only running half to 3/4 of the way down the foot cause a problem
There isn’t a stable surface to push off of causing more knee flexion
What does a short keel result in
Rolling onto rubber causing knee flexion resulting in falling down to the ground
True or False:
New keels run the entire length of the SACH foot
True
What determines when PF occurs in a SACH prosthetic foot
The squishiness of the heel
What happens if the heel of a SACH foot is too squishy
PF at the ankle and hyperextension at the knee
What happens if the heel of a SACH foot is too firm
DF at the ankle and flexion at the knee
What motions does a single axis/exoskeletal prosthetic foot allow
PF and DF
What do the bumpers in a single axis/exoskeletal prosthetic foot do
Resist compression
What motions does a multiaxial/exoskeletal prosthetic foot allow
PF, DF, IV, and EV
What is an elastic keel
Rubberized material that runs all the way to the toes
Where does the keel extend in a dynamic response prosthetic foot
Top of the prosthesis
What does the keel extending to the top of the prosthesis in a dynamic response prosthetic foot allow for
Motion and loading of the shin area
What allows for IV and EV in a dynamic response prosthetic foot
The split down midline
True or False:
A dynamic response prosthetic foot is better for a tall person because of the longer keel allowing more loading and motion
True
In a dynamic response foot with a pneumatic/hydraulic pump what does adding more air do
Leads to less compression so less PF and hyperextension at the knee occur
In a dynamic response foot with a pneumatic/hydraulic pump what does removing air do
Leads to more compression so more PF and hyperextension at knee
True or False:
The foot should be relatively horizontal to the sole
True
How big is the standard prosthetic foot heel
3/4”
How big is an athletic prosthetic foot heel
3/8”
How is a western boot prosthetic foot heel
2”
What is looked at when choosing an appropriate foot (8)
- Heel height
- Ability to resist moisture
- Cosmetic appearance of toes
- Prosthetic user’s activity level
- Ability or potential to reach a higher level
- Vocational/recreational
- Maintenance/distance to prosthetist
- Team effort/clinic team
What is used to label the prosthetic user’s ability or potential
Medicare K levels
How many medicare K levels are there
5, K0-K4
What is K0
To ambulate or transfer safely with or without assistance and a prosthesis does not enhance QOL or mobility
What is K1
To use a prosthesis for transfers, or ambulation on level surfaces at a fixed cadence
What is K2
Transverse low level barriers, curbs, stairs or uneven surfaces, limited community ambulator
What is K3
Variable cadence beyond simple walking
What is K4
Ambulatory skills, high impact, children, active adults, and athletes
What type of foot is available for K1 and K2
Simplest feet (SACH)
What type of foot is available for K3 and K4
Dynamic response feet and more complex
Who determines the K level
The physician
