What are the two types of stability we talked about?
- alignment stability
- dynamic stability
What must stability be balanced with? Why?
- mobility
- need knee to bend for swing phase (clearance)
What is alignment stability driven by?
where components are positioned relative to TKA line
What is dynamic stability?
- How the amputee is able to control the residual limb
- Depends on muscle/strength
Categories of prosthetic feet
- static
- dynamic response
What are the static feet we talked about?
- SACH foot
- single axis
- multi-axis
- split keel foot
- flexible heel
SACH foot =
Solid
Ankle
Cushioned
Heel
Who uses a SACH foot?
lower level individuals
Single axis foot
- adds some basic articulation
- Doesn’t allow much DF before tibial advancement
Single axis foot: DF/PF bumpers
- Has DF stop and a PF bumper
- doesn’t need much anterior give
Who would use a single axis foot?
Someone who only needs it for walking
What is a multi-axis foot good for?
- allows M/L motion
- adapts to uneven terrain
Split keel foot
allows each side of the foot to move independently
Flexible keel
- runs almost entire length of foot
- flexible enough to allow toe break and simulate DF
Flexible keel: energy storage
does NOT store energy
STATIC
What is a dynamic response foot?
- foot that stores and releases energy for a more active toe-off
- decreases energy consumption
How does a dynamic response foot decrease energy consumption?
gives back some energy in terminal stance
What is the driving force for component choice?
anticipated functional level
Fancy feet and reimbursement concerns
Most won’t pay top dollar for low functioning individuals
