Prosthetic Gait Deviations

Question 1

Knee should be at ___ degrees of ____ to promote WB through patella

Answer 1

5-10 deg of flex

Question 2

Normal gait:
____ moment throughout stance
Slight ___ moment (~1/2 in)
Slight toe-____

Answer 2

FLEXIO moment throughout stance
Slight VARUS moment (~1/2 in)
Slight toe-OUT

Question 3

BKA Prosthetic causes for excessive knee extension

Answer 3

• foot too anterior to socket
• heel cushion too soft
• excessive PF of foot

Question 4

BKA Prosthetic causes for excessive knee flexion

Answer 4

• heel too firm
• foot too far posterior
• foot too DF

Question 5

BKA Patient causes for excessive knee extension

Answer 5

Shoe heel too low
Excessive use of extensors

Question 6

BKA Patient causes for excessive knee flexion

Answer 6

• Shoe heel too high
• knee flexion contracture
• weak quads

Question 7

BKA Prosthetic causes for excessive varus thrust

Answer 7

Pylon leans laterally
Foot too inset
Socket too wide

Question 8

BKA Prosthetic causes for excessive valgus thrust

Answer 8

Pylon lean medially
Foot too outset
Socket too wide

Question 9

BKA Prosthetic causes for excessive lateral bend to prosthetic side

Answer 9

Prosthetic too short
Abducted socket

Question 10

BKA Patient causes for excessive lateral bend to prosthetic side

Answer 10

Lateral distal limb pain
Weak hip abductor
Limb volume

Question 11

BKA Prosthetic causes for abrupt heel off (drop-off)

Answer 11

• toe lever arm too short
• toe too soft due to excess posterior position of foot
• foot excessively DF
• socket in too much flexion

Question 12

BKA Patient causes for abrupt heel off (drop-off)

Answer 12

Heel height too high

Question 13

BKA Prosthetic causes for pistoning

Answer 13

Socket too large
Suspension inadequate

Question 14

BKA Patient causes for pistoning

Answer 14

Limb shrinking

Question 15

BKA Prosthetic causes for foot medial whip

Answer 15

Knee internally rotated

Question 16

BKA Prosthetic causes for foot lateral whip

Answer 16

Knee externally rotated

Question 17

BKA Prosthetic causes for medial or lateral foot whip

Answer 17

Inadequate suspension

Question 18

BKA Patient causes for medial or lateral foot whip

Answer 18

-Irregular loading at terminal stance
- improperly donned prosthesis

Question 19

AKA prosthetic causes for knee instability

Answer 19

• knee axis too far anterior —> flexion moment
• heel cushion too hard (hard to create flexion moment at heel strike)

Question 20

AKA patient causes for knee instability

Answer 20

• hip flexion contracture
• hip extensor weakness
• change in heel height

Question 21

AKA patient causes for foot slap

Answer 21

Forces heel into ground to ensure complete knee extension/stability

Question 22

AKA prosthetic causes for foot slap

Answer 22

• Insufficient PF resistance in the prosthetic foot
• Heel cushion too soft for users weight and activity level

Question 23

AKA Prosthetic cause of ER of prosthetic foot

Answer 23

• excessively firm heel cushion
• toe out
• socket too wide

Question 24

AKA Patient cause of ER of prosthetic foot

Answer 24

• poor muscle control
• limb shrinkage

Question 25

AKA Prosthetic causes for abducted gait

Answer 25

• Medial brim of socket too high • Prosthesis too long • Insufficient femur support by lateral wall • Socket too abducted

Question 26

AKA patient causes for abducted gait

Answer 26

• Increased volume of the limb • Excess pressure on the pubic ramus • Pain at distal lateral femur • Contracted hip abductors • Patient insecurity, habit

Question 27

AKA prosthetic causes for excessive lateral trunk bend

Answer 27

• Prosthesis is too short • Excessively outset foot • Medial wall of the socket too high • Adduction of socket inadequate (too much abduction)

Question 28

AKA patient causes for excessive lateral trunk bend

Answer 28

- weak abductors - pain - limb shrinkage: too deep in socket

Question 29

AKA prosthetic causes for pelvic rise

Answer 29

• Toe lever too long • Foot placed too anteriorly with respect to knee/socket • Excessively plantarflexed foot

Question 30

AKA prosthetic causes for drop-off

Answer 30

• Toe lever too short • Foot too dorsiflexed

Question 31

AKA prosthetic causes for inadequate or delayed knee flexion

Answer 31

• Excessive mechanical resistance to knee flexion • Prosthesis aligned with too much stability

Question 32

AKA prosthetic causes for circumduction

Answer 32

• Prosthetic knee with excessive mechanical resistance to knee flexion • Prosthetic knee locked in extension (extension bias too strong) • Prosthesis too long

Question 33

AKA prosthetic causes for vaulting

Answer 33

• Inadequate socket suspension • Prosthesis too long • Too much resistance to knee flexion • Prosthetic knee locked in extension (extension bias too strong)

Question 34

AKA prosthetic causes for excessive terminal impact

Answer 34

Shin of prosthesis moves forward so quickly that the fully extended position is reached early

Question 35

AKA patient causes for excessive terminal impact

Answer 35

• Forceful hip flexion in initial swing to build momentum for knee extension • Forcefully extends hip in terminal swing to snap knee into full extension in preparation for initial contact

Question 36

AKA prosthetic causes for unequal step length

Answer 36

Insufficient initial socket flexion to accommodate hip flexion contracture —> long step on prosthetic side

Question 37

AKA patient causes for unequal step length

Answer 37

- excessive L lordosis - hip flexion contracture - fear of falling - pain