PROSTHETIC ASSISTANT UPDATED EXAM STUDY GUIDE
QUESTIONS AND ANSWERS MARKED A+
✔✔TT PT comes in, upon examining gait you notice a mild extension moment at the
knee in stance phase. What could be the cause? - ✔✔Prosthetic heel is too soft
✔✔Dorsiflexing the prosthetic foot is synonymous with - ✔✔Flexing the prosthetic
socket
✔✔In reference to TT prosthetic excessive adduction of the prosthetic pylon would
cause what at midstance in gait? - ✔✔Genu varum
✔✔TT pt comes in, at heel strike the SACH prosthesis rotates externally. What would
be 1 cause of the gait deviation? - ✔✔The prosthetic heel durometer is too firm
✔✔When the prosthetic foot inset is increased, socket pressure will become more
apparent - ✔✔Lateral/distal and medial/proximal
✔✔When aligning the prosthetic socket in relations to the prosthetic foot, forces present
in the socket increase - ✔✔Anterior/proximal and posterior/distal
✔✔Upon heel strike for a BK, where are the anterior/posterior forces? -
✔✔Anterior/distal and Posterior proximal
✔✔Bench alignment of a BK begins with the - ✔✔center of the posterior brim 1/2"
lateral to the center of the heel
✔✔In correcting an abducted socket on the adjustable leg, we should - ✔✔release the
medial tilt screw and tighten the lateral
✔✔What is the effect of excessively shimming the dorsiflexion stop to place the shank
in vertical position? - ✔✔Excessive shortening in range of plantarflexion, resulting in
stiffened plantar bumper action and knee instability
✔✔What is the result of locating the toe-break too far forward in the prosthetic foot? -
✔✔Gives the amputee a feeling of "climbing a hill" causing excessive energy
consumption and awkward gait
✔✔If the amputee complains of difficulty rolling over the ball of the foot, the most likely
cause is - ✔✔Excessive plantarflexion
✔✔If the pt complains of prolonged anterior/distal tibia discomfort, the probable cause is
- ✔✔Foot too dorsiflexed
,✔✔When bench aligning a BK, the medial/lateral placement is - ✔✔inset 1/2"
✔✔When the prosthetic foot is placed in excessive dorsiflexion - ✔✔The knee is made
unstable
✔✔With a PTB prosthesis, excessive knee flexion occurs after heel strike. Which of the
following foot and socket adjustments best correct the problem? - ✔✔Move the foot
anterior and decrease socket flexion
✔✔When a BK pt controls the tendency of the knee to flex after heel strike, pressures
are increased on which areas of the limb? - ✔✔Anterior/distal and Posterior/proximal
✔✔If the foot of a PTB prosthesis is moved too far laterally on the adjustable leg, it will
cause excessive pressure on which area of the limb? - ✔✔Medial/distal and lateral
proximal
✔✔A BK comes in and feels anterior/distal discomfort in his prosthetic. How should you
address the problem? - ✔✔Extend the prosthetic socket
Add pretibial pads to the prosthetic socket
✔✔A BK comes in wearing a PTB style endoskeletal prosthesis with general knee pain
and distal end pressure. PT takes off the prosthesis and liner and there is redness on
the distal tibia and inferior aspect of the patella bone. What is the most logical clinical
action to address the problem? - ✔✔Add a gastroc pad to the prosthetic socket
Add a 1 ply prosthetic sock over the liner
✔✔A TT pt comes in, they have been using a TT prosthesis sucessfully for 10 yrs but
the patient has a grade 1 OCD to his medial femoral condyle that is painful in weight
bearing. What alignment could assist the discomfort - ✔✔Outset the foot 3mm
✔✔What is the effect on gait of lengthening the posterior lever arm of the foot? -
✔✔Tends to flex the knee at heel strike
✔✔A BK comes in, and has posterior knee or hamstring discomfort. How should you
address the problem? - ✔✔Lower the posterior medial brim on the prosthetic socket
Flex the prosthetic socket
Align prosthetic food more posterior in relation to the prosthetic socket
✔✔TT prosthetic sockets that are excessively extended cause excessive pressure in
what area? - ✔✔Anterior/proximal and posterior/distal
, ✔✔When external rotation of the prosthetic foot is needed the toe lever or keel of the
foos is relatively - ✔✔Shortened
✔✔Coronal bench alignment for a TF prosthesis - ✔✔Socket is adducted 6-7°
Foot is 37-50mm outset of the ischium
✔✔Sagittal bench alignment for a TF prosthesis - ✔✔5° socket flexion + contracture
Socket is 5-15mm anterior to the knee
✔✔Transverse bench alignment for a TF prosthesis - ✔✔Knee externally rotated by 3-
5°
Foot externally rotated by 5-7°
✔✔Why is the socket flexed to 5° for a TF? - ✔✔Stretch hamstrings
For biomechanical advantage
To reduce lordosis
✔✔Why should an additional hip flexion be included in the alignment of TF prosthesis? -
✔✔Accommodate contracture
Reduce lordosis
✔✔Why should a TF socket be anterior to the knee? - ✔✔Generate a knee extension
moment
✔✔Why should the socket be adducted for a TF? - ✔✔Normal femoral angle
Stretches the glutes and abductors
✔✔How many degrees is the normal femoral angle? - ✔✔6-8°
✔✔Why is the foot externally rotated in bench alignment for a TF? - ✔✔Lateral stability
Position foot for loading response
Normal weight line progression through foot
✔✔What does plantargrade mean? - ✔✔Foot flat in shoe
✔✔Why is the foot location relative to the ischial line important? - ✔✔Generates varus
moment at the hip
✔✔What is the purpose of the ischial containment? - ✔✔Med/lat stability by creating
bony lock
Opposes the lateral wall
Offloads the lateral/distal femur
QUESTIONS AND ANSWERS MARKED A+
✔✔TT PT comes in, upon examining gait you notice a mild extension moment at the
knee in stance phase. What could be the cause? - ✔✔Prosthetic heel is too soft
✔✔Dorsiflexing the prosthetic foot is synonymous with - ✔✔Flexing the prosthetic
socket
✔✔In reference to TT prosthetic excessive adduction of the prosthetic pylon would
cause what at midstance in gait? - ✔✔Genu varum
✔✔TT pt comes in, at heel strike the SACH prosthesis rotates externally. What would
be 1 cause of the gait deviation? - ✔✔The prosthetic heel durometer is too firm
✔✔When the prosthetic foot inset is increased, socket pressure will become more
apparent - ✔✔Lateral/distal and medial/proximal
✔✔When aligning the prosthetic socket in relations to the prosthetic foot, forces present
in the socket increase - ✔✔Anterior/proximal and posterior/distal
✔✔Upon heel strike for a BK, where are the anterior/posterior forces? -
✔✔Anterior/distal and Posterior proximal
✔✔Bench alignment of a BK begins with the - ✔✔center of the posterior brim 1/2"
lateral to the center of the heel
✔✔In correcting an abducted socket on the adjustable leg, we should - ✔✔release the
medial tilt screw and tighten the lateral
✔✔What is the effect of excessively shimming the dorsiflexion stop to place the shank
in vertical position? - ✔✔Excessive shortening in range of plantarflexion, resulting in
stiffened plantar bumper action and knee instability
✔✔What is the result of locating the toe-break too far forward in the prosthetic foot? -
✔✔Gives the amputee a feeling of "climbing a hill" causing excessive energy
consumption and awkward gait
✔✔If the amputee complains of difficulty rolling over the ball of the foot, the most likely
cause is - ✔✔Excessive plantarflexion
✔✔If the pt complains of prolonged anterior/distal tibia discomfort, the probable cause is
- ✔✔Foot too dorsiflexed
,✔✔When bench aligning a BK, the medial/lateral placement is - ✔✔inset 1/2"
✔✔When the prosthetic foot is placed in excessive dorsiflexion - ✔✔The knee is made
unstable
✔✔With a PTB prosthesis, excessive knee flexion occurs after heel strike. Which of the
following foot and socket adjustments best correct the problem? - ✔✔Move the foot
anterior and decrease socket flexion
✔✔When a BK pt controls the tendency of the knee to flex after heel strike, pressures
are increased on which areas of the limb? - ✔✔Anterior/distal and Posterior/proximal
✔✔If the foot of a PTB prosthesis is moved too far laterally on the adjustable leg, it will
cause excessive pressure on which area of the limb? - ✔✔Medial/distal and lateral
proximal
✔✔A BK comes in and feels anterior/distal discomfort in his prosthetic. How should you
address the problem? - ✔✔Extend the prosthetic socket
Add pretibial pads to the prosthetic socket
✔✔A BK comes in wearing a PTB style endoskeletal prosthesis with general knee pain
and distal end pressure. PT takes off the prosthesis and liner and there is redness on
the distal tibia and inferior aspect of the patella bone. What is the most logical clinical
action to address the problem? - ✔✔Add a gastroc pad to the prosthetic socket
Add a 1 ply prosthetic sock over the liner
✔✔A TT pt comes in, they have been using a TT prosthesis sucessfully for 10 yrs but
the patient has a grade 1 OCD to his medial femoral condyle that is painful in weight
bearing. What alignment could assist the discomfort - ✔✔Outset the foot 3mm
✔✔What is the effect on gait of lengthening the posterior lever arm of the foot? -
✔✔Tends to flex the knee at heel strike
✔✔A BK comes in, and has posterior knee or hamstring discomfort. How should you
address the problem? - ✔✔Lower the posterior medial brim on the prosthetic socket
Flex the prosthetic socket
Align prosthetic food more posterior in relation to the prosthetic socket
✔✔TT prosthetic sockets that are excessively extended cause excessive pressure in
what area? - ✔✔Anterior/proximal and posterior/distal
, ✔✔When external rotation of the prosthetic foot is needed the toe lever or keel of the
foos is relatively - ✔✔Shortened
✔✔Coronal bench alignment for a TF prosthesis - ✔✔Socket is adducted 6-7°
Foot is 37-50mm outset of the ischium
✔✔Sagittal bench alignment for a TF prosthesis - ✔✔5° socket flexion + contracture
Socket is 5-15mm anterior to the knee
✔✔Transverse bench alignment for a TF prosthesis - ✔✔Knee externally rotated by 3-
5°
Foot externally rotated by 5-7°
✔✔Why is the socket flexed to 5° for a TF? - ✔✔Stretch hamstrings
For biomechanical advantage
To reduce lordosis
✔✔Why should an additional hip flexion be included in the alignment of TF prosthesis? -
✔✔Accommodate contracture
Reduce lordosis
✔✔Why should a TF socket be anterior to the knee? - ✔✔Generate a knee extension
moment
✔✔Why should the socket be adducted for a TF? - ✔✔Normal femoral angle
Stretches the glutes and abductors
✔✔How many degrees is the normal femoral angle? - ✔✔6-8°
✔✔Why is the foot externally rotated in bench alignment for a TF? - ✔✔Lateral stability
Position foot for loading response
Normal weight line progression through foot
✔✔What does plantargrade mean? - ✔✔Foot flat in shoe
✔✔Why is the foot location relative to the ischial line important? - ✔✔Generates varus
moment at the hip
✔✔What is the purpose of the ischial containment? - ✔✔Med/lat stability by creating
bony lock
Opposes the lateral wall
Offloads the lateral/distal femur
