16 - LE Prosthetic Gait Deviations

describe this translation

posterior socket translation

describe this translation

anterior socket translation

describe this translation

medial socket translation

describe this translation

lateral socket translation

when the socket is placed too far anterior on the foot, does the person feel like they’re walking up or downhill?

downhill

when the socket is placed too far posterior on the foot, does the person feel like they’re walking up or downhill?

uphill

what are the prosthetic causes if there is excessive knee extension at heel strike to mid stance?

Heel cushion is too soft (rapid PF leads to knee extension)

Toe lever arm is too long (forces knee into hyperextension)

Socket placed too far posterior on the foot

what are the amputee causes if there is excessive knee extension at heel strike to mid stance?

Weakness of quadriceps (compensation)

Habit pattern

what happens if the heel cushion is too soft (heel strike to midstance)

rapid PF leads to knee extension

what happens if the toe lever arm is too long (heel strike to midstance)

forces knee into hyperextension

what are the prosthetic causes if there is excessive knee instability at heel strike to mid stance?

Heel cushion is too hard (limited PF leads to knee flexion)

Toe lever arm is too short) (forces knee into flexion)

Socket placed too far anterior on the foot

what are the amputee causes if there is excessive knee instability at heel strike to mid stance?

Quad weakness

Habit pattern

what happens if the heel cushion is too hard (heel strike to midstance)

limited PF leads to knee flexion

what happens if the toe lever arm is too short (heel strike to midstance)

forces knee into flexion

how would you accommodate a knee flexion contracture in a TTA?

move socket posteriorly to force knee into extension

what are the prosthetic causes if there is lateral bending in midstance (generally towards prosthetic side)

Prosthesis too short

Lateral wall fail to adequately support femur

High medial wall causes discomfort

Prosthesis aligned in abduction leading to wide base gait

what are the amputee causes if there is lateral bending in midstance (generally towards prosthetic side)

Inadequate abduction strength

Abduction contracture

Very short limb may fail to provide sufficient lever arm

Habit pattern

what are the prosthetic causes if the prosthesis held away from midline at all times (abducted gait) in midstance?

Prosthesis too long

Too much abduction built in prosthesis

High medial wall causes discomfort

Lateral wall fail to adequately support femur

what are the amputee causes if the prosthesis held away from midline at all times (abducted gait) in midstance?

Inadequate abduction strength

Abduction contracture

Habit pattern

what is vaulting gait?

rises on toe of sound side to permit swing through with limited knee flexion

prosthetic causes of vaulting gait

Prosthesis too long

Inadequate socket suspension

amputee causes of vaulting gait

Fear of stubbing prosthetic toe

Limb discomfort

Habit pattern (common)

cause of drop off gait

premature knee flexion before toe off

what phase of gait does drop off gait and valuting gait happen?

terminal stance

prosthetic causes of drop off gait

toe lever too short

socket placed anterior on the foot

amputee causes of drop off gait

none

what is circumduction gait

prosthesis swung laterally in wide arc

prosthetic causes of circumduction gait

prosthesis too long

knee is too stiff to bend knee for swing through

amputee causes of circumduction gait

Inadequate abduction / hip flexion strength

Abduction contracture

Lack confidence for flexing prosthetic knee

Habit pattern

what is uneven heel raise gait

rapid rise of prosthetic heel during early swing phase

what phase of gait does uneven heel raise happen, medial/lateral whips, and circumduction gait?

swing

prosthetic causes of uneven heel rise

(think this is normally controlled by rectus femoris eccentric activity)

Insufficient knee joint friction

Inadequate extension aid

amputee causes of uneven heel rise

Excessive hip flexion forcing knee into flexion

cause of medial or lateral whips

when the heel moves medially or laterally at the beginning of swing phase

prosthetic causes of medial/lateral whips

Excessive IR / ER of prosthetic knee

Socket may be too tight

Excessive valgus of prosthetic knee

amputee causes of medial/lateral whips

faulty walking habits

what happens to the knee in terminal swing impact gait deviation?

knee snaps into extension before heel strike

prosthetic causes of terminal swing impact

Insufficient knee friction

Knee extension aid is too strong

amputee causes of terminal swing impact

amputee assuring the the knee is in full extension by deliberately and forcibly extending residual limb before heel strike

what

what causes the foot rotation deviation in heel strike?

rotation of the prosthetic foot on heel strike

prosthetic causes of foot rotation in heel strike

Too much resistance to PF (heel bumper too hard)

Too much toe-out built into prothesis

Too loose socket

amputee causes of foot rotation in heel strike

Vigorous extension at heel strike

Poor hip rotation control

what causes foot slap in heel strike

too rapid descent of foot in heel strike

prosthetic causes of foot slap

PF resistance is too soft

amputee causes of foot slap

Amputee driving the prosthesis into the walking surface too hard to assure knee extension

prosthetic causes of knee instability in heel strike

Knee joint too far ahead of TKA line (trochanter to ankle axis)

Insufficient flexion built into socket

PF resistance may be too great causing knee to buckle at heel strike

Failure to limit DF lead to poor knee control at toe off

amputee causes of knee instability in heel strike

Hip extensor weakness

Hip flexion contracture

prosthetic causes of reduced arm swing

poorly fitted socket causing limb discomfort

amputee causes of reduced arm swing

Poor balance (hip control)

Uneven step length

Vaulting, Circumducted, Abducted gait

prosthetic causes of uneven step length

Poorly fitted socket causing limb discomfort

Weak extension aid or insufficient friction in the prosthetic knee leading to excessive heel rise

Knee buckles too easily

amputee causes of uneven step length

Poor balance (hip control)

Extension weakness (hip and / or knee)

Fear and insecurity

what causes excessive trunk extension in gait?

active lumber lordosis in stance of prosthetic side

prosthetic causes of excessive trunk extension

Improperly shaped posterior wall may cause forward rotation of the pelvis to avoid full weight-bearing on the ischium

Insufficient initial flexion (?) built into the socket

amputee causes of excessive trunk extension

Hip flexor tightness

Substitution of lumbar erector spinae for weak hip extensors

Weak abdominals

Moving shoulders backwards in an effort to obtain better balance

what are the pressure intolerant areas in TTA?

fibular head, tibial crest, distal end of the tibia, and the hamstring insertions/tendons

what are the pressure intolerant areas in TFA?

distal femur, the pubic ramus, adductor rolls

wear schedule for prosthetics

2, 2, 20

2 hours on, 2 hours off, < 40 min weight bearing in 2 hours

what are the expected pressure patterns in TTA?

femoral condyles, patellar tendon, med tibial flare, tibial shaft, ant and post compartments

what are the expected pressure patterns in TFA?

soft tissues, ischial tuberosity

how should you progress the wearing schedule?

1 hour every 2-3 days

if the patient is over ____ socks, they need a new socket

10-15

how are prosthetic socks applied?

over a thin sheath with THICKEST layer against skin

no wrinkles

for socks, increase by ___ ply at a time

one

if a sock is used with a gel liner, where does the sock go?

sock goes over the liner and NOT against the skin

when are soft liners mostly used?

TTA where bone is prominent or there’s increased skin sensitivity

what are the soft liners made out of?

pelite, nickelplast, PPT, silicone gel, plastazote & leather

what is the expected fit of soft liners?

exact/tight fit into the prosthesis

how do you put on a soft liner?

Don sheath/apply appropriate ply of sock and gently pull the liner on from the top as its pushed up from the bottom

how are gel liners worn? why are they beneficial?

directly against the skin

decreases shearing on the skin and can be used with more fragile skin

how do you put on a gel liner?

Donn the liner by turning it inside out, create a cup, and roll it on. Pulling on the top of the liners often rip them

If the patient perspires heavily, use an Al containing spray to control perspiration

how do you clean a gel liner?

several times a day take the liners off and spray them with alcohol and wipe them off with a linen towel.

Hand wash them each evening in mild soap and rinse well.

Hang on the stands inside out.

how do you clean soft liners?

wipe them with a damp cloth

how do you clean prosthetic socks?

washed in mild soap and rinsed well: no washer or dryer

rolled in a towel for drying

how do you clean sockets?

wash out with a damp cloth and make sure all detergent is removed

how do you clean endoskeletal components?

return to the prosthetist to replace stockings/foam with tears and runs

hand wash stockings with mild soap if removable

Most TT amputees don the prostheses in ____

sitting

TF amputees need to have socket aligned in _____ ______ if donning in sitting to match the position of the residual limb

external rotation

when can TFA stand to don a prosthesis?

stand if a unilateral amputee, or do a combination of sitting to don one prosthesis and stand for the second if a bilateral amputee.

what is the most common problem when donning the prosthesis?

excessive prosthetic rotation

process of donning a TT prosthesis

secure suspension sleeves by rolling them up, buckle corsets and cuffs

make sure there are no wrinkles to irritate the skin

weight bear to fully seat the residual limb in the prosthesis and check to ensure that you have proper alignment

begin ambulation

process of donning a TF prosthesis

Once in the socket

Loosely buckle the pelvic band, or Silesian belt

Stand and apply appropriate WB pressure and tighten the belts enough for adequate suspension but not too much causing hip IR

Roll the top of any gel liner down over the brim of the prosthesis

process of donning a TF prosthesis if patient is using full suction suspension without a lubricant

stand without weight bearing and place the end of the silk sock/ace wrap through the distal valve hole and begin working the residual limb deeper into the socket as the material is pulled out

gradually increase WB as this is done to fully seat the residual limb in the socket

process of donning a TF total suction suspension

Once the prosthesis is on, replace the valve and if not an automatic valve, bleed the excess air out of the socket to ensure adequate suspension

If the patient uses lubricant, liberally rub the lubricant onto the skin, don the prosthesis in either sitting or standing, and increase weight bearing until fully seated.

for TF prosthesis, once in the socket fully, check to ensure….

proper alignment

once you have the TF prosthesis on, take the first step with which leg to ensure knee lock?

sound leg

Good understanding of the location of the _____ is essential for gait with TF to ensure knee locking at heelstrike → toe off

COG

what happens to the prosthetic when the line of gravity is in front of the knee?

knee extends and locks

what happens to the prosthetic when the line of gravity is behind the knee?

flexes

progression of sit to stand

• parallel bars

• outside parallel bars

• assistive device

• independent

how to progress weight shifting and balancing

stand in parallel bars → no hands

what direction should u weight shift first?

side to side → forwards and backwards

to practice repetitive single stepping, what leg do you step with first? why?

sound leg to foster prosthetic weight acceptance and enforce knee lock with TF patients

progression of gait training in the parallel bars

forward progression

backwards

side stepping

gait with Assistive Devices Progression:

• walker,

• 2 forearm crutches

• 1 forearm crutch

• WBQC

• NBQC

• straight cane

• freedom under good weather conditions

progression of falling with protective methods

expected

unexpected

unexpected (multidirectional)

prosthetic gait training interventions examples (for reference)

• Single stance on the prosthesis (shake a leg)

• Unsupported standing with controlled swaying and then dynamic recovery

• Kick ball, catching and throwing

• Ascending and descending inclines and ambulating on uneven surfaces

• Controlled lowering to the floor

• Floor to stand

for microprocessor legs, what is the best way to descend stairs?

“ride knee down” after placing mid foot on the tread edge

Most bilateral amputees do well if they are…

medically stable, heal well, are not too debilitated, and have proprioception and kinesthesia

what are the combinations of potential bilateral amputations?

Partial bilateral foot

Partial foot/TT

Bilateral TT

TT and TF