LOWER EXTREMITY PROSTHETIC WRITTEN
SIMULATION STUDY GUIDE QUESTIONS WITH
CORRECT ANSWERS 2026/2027
SAFE Foot
Stationary Attachment Flexible Endoskeleton
Components of Prescription Recommendation (14)
General Prosthesis (R, L, Bilateral)
Stage of care (IPOP, EPOP, temporary, definitive)
Prosthesis structure (Endo, Exo)
Socket Design (PTB, PTB-SC, PTB-SCSP, TSB, quad, IC)
Total Contact (Yes, why?)
Socket structure (laminated, thermoplastic, rigid frame w/ flexible inner)
Suspension (cuff, sleeve, pin, Silesian, liner, lanyard, magnetic, joint + corset,
lanyard, suction, vacuum)
Distal end pad (Yes, no, why?)
Interface (no, socks, liner, Pelite, sheaths, why?)
Knee including features (single axis, polycentric, MPK, etc)
Foot (SACH, single axis, multi axial, flexible keel, dynamic response, articulated,
hydrualic, MPK)
Alignment (manufacturer's recommendations, knee flexion contracture)
Cosmesis (cover, waterproofing, no cover, why?)
Additional Components (socks, shrinkers, foot add on codes, acrylic, ultralight,
axial rotator, alignable system)
K0 definition
No transfers, no ambulation, no prosthesis
K1 definition
What feet do you provide?
,Transfers only
SACH Foot
K2 definition
What feet do you provide?
Ambulation in home and outdoors at fixed cadence, can traverse low level barriers
like curbs, stairs, uneven surfaces
K2 foot: single axis, flexible keel, multi-axial, hydraulic
What is definintion of flexible keel foot?
spongy, energy absorbing
short, compliant keel that conforms to uneven terrain
What is definition of a multi-axial foot?
Allows DF/PF and INV/EV
Accommodates uneven terrain
K2 or K3 but usually K2
What is definition of hydraulic foot?
Foot that has hydraulics to adjust DF/PF resistance
K3 definition
What feet do you provide?
Ambulation in home and outdoors with variable cadence
K3 foot: dynamic response, ESAR, hydraulic, microprocessor
What is definition of dynamic response foot?
foot has deformable keel with lively, springy response
What is definition of ESAR foot?
Indications for microprocessor knee
(codes for C-Leg 4)
,K3 patients who have tried other knees and are at risk of falling
If they don't have insurance for MPK, do weight-activated stance control
L5828 - fluid swing and stance
L5845 - stance flexion
L5848 - fluid stance extension, adjustable
L5856 - MPK
What is swing and stance?
"Safety knee"
allows for flexion up to 20 degrees and then resists, prevents patient from falling
prevents knee hyperextension
K4 definition
Exceeds basic/moderate ambulation
Athletes, olympians, kids
Pressure tolerant areas for PTB
patellar tendon
medial tibial flare
pretibial area
medial shaft of tibia
lateral shaft of fibula
gastrocnemius
supracondylar area (if PTB-SC or PTB-SCSP)
Areas that need relief for PTB
patella
lateral tibial flare
tibial tubercle
crest of tibia
distal end
fibular head
, fibular neck (peroneal nerve)
cut end of fibula
peroneal nerve
hamstring tendons
Define PTB socket
Patellar Tendon Bearing Socket
Suspends limb by pressing into pressure-tolerant areas and relieving bony non-
tolerant areas
Indications for PTB socket
Mature limb, well-healed, no volume fluctuation
Tolerant to PTB pressures
Non-bony limb
Contraindications of PTB socket
New amputees
Volume fluctuation
Very bony
Thin skin
DM/PVD
Advantages of PTB Socket
Sweat doesn't corrode socket
Less bulky at knee vs socket w/ liner
Easy to clean
Socket is very durable
Disadvantages of PTB
Difficult to fit with sensitive or bony limbs
Not easily modified vs socket w/ flexible inner liner
Indications of PTB w/ Pelite liner
SIMULATION STUDY GUIDE QUESTIONS WITH
CORRECT ANSWERS 2026/2027
SAFE Foot
Stationary Attachment Flexible Endoskeleton
Components of Prescription Recommendation (14)
General Prosthesis (R, L, Bilateral)
Stage of care (IPOP, EPOP, temporary, definitive)
Prosthesis structure (Endo, Exo)
Socket Design (PTB, PTB-SC, PTB-SCSP, TSB, quad, IC)
Total Contact (Yes, why?)
Socket structure (laminated, thermoplastic, rigid frame w/ flexible inner)
Suspension (cuff, sleeve, pin, Silesian, liner, lanyard, magnetic, joint + corset,
lanyard, suction, vacuum)
Distal end pad (Yes, no, why?)
Interface (no, socks, liner, Pelite, sheaths, why?)
Knee including features (single axis, polycentric, MPK, etc)
Foot (SACH, single axis, multi axial, flexible keel, dynamic response, articulated,
hydrualic, MPK)
Alignment (manufacturer's recommendations, knee flexion contracture)
Cosmesis (cover, waterproofing, no cover, why?)
Additional Components (socks, shrinkers, foot add on codes, acrylic, ultralight,
axial rotator, alignable system)
K0 definition
No transfers, no ambulation, no prosthesis
K1 definition
What feet do you provide?
,Transfers only
SACH Foot
K2 definition
What feet do you provide?
Ambulation in home and outdoors at fixed cadence, can traverse low level barriers
like curbs, stairs, uneven surfaces
K2 foot: single axis, flexible keel, multi-axial, hydraulic
What is definintion of flexible keel foot?
spongy, energy absorbing
short, compliant keel that conforms to uneven terrain
What is definition of a multi-axial foot?
Allows DF/PF and INV/EV
Accommodates uneven terrain
K2 or K3 but usually K2
What is definition of hydraulic foot?
Foot that has hydraulics to adjust DF/PF resistance
K3 definition
What feet do you provide?
Ambulation in home and outdoors with variable cadence
K3 foot: dynamic response, ESAR, hydraulic, microprocessor
What is definition of dynamic response foot?
foot has deformable keel with lively, springy response
What is definition of ESAR foot?
Indications for microprocessor knee
(codes for C-Leg 4)
,K3 patients who have tried other knees and are at risk of falling
If they don't have insurance for MPK, do weight-activated stance control
L5828 - fluid swing and stance
L5845 - stance flexion
L5848 - fluid stance extension, adjustable
L5856 - MPK
What is swing and stance?
"Safety knee"
allows for flexion up to 20 degrees and then resists, prevents patient from falling
prevents knee hyperextension
K4 definition
Exceeds basic/moderate ambulation
Athletes, olympians, kids
Pressure tolerant areas for PTB
patellar tendon
medial tibial flare
pretibial area
medial shaft of tibia
lateral shaft of fibula
gastrocnemius
supracondylar area (if PTB-SC or PTB-SCSP)
Areas that need relief for PTB
patella
lateral tibial flare
tibial tubercle
crest of tibia
distal end
fibular head
, fibular neck (peroneal nerve)
cut end of fibula
peroneal nerve
hamstring tendons
Define PTB socket
Patellar Tendon Bearing Socket
Suspends limb by pressing into pressure-tolerant areas and relieving bony non-
tolerant areas
Indications for PTB socket
Mature limb, well-healed, no volume fluctuation
Tolerant to PTB pressures
Non-bony limb
Contraindications of PTB socket
New amputees
Volume fluctuation
Very bony
Thin skin
DM/PVD
Advantages of PTB Socket
Sweat doesn't corrode socket
Less bulky at knee vs socket w/ liner
Easy to clean
Socket is very durable
Disadvantages of PTB
Difficult to fit with sensitive or bony limbs
Not easily modified vs socket w/ flexible inner liner
Indications of PTB w/ Pelite liner
