Lower Extremity Prosthetic Gait Deviations

Decreased Step Length Prosthetic Side: Non-Prosthetic Cause

transtibial - knee flexion contracture

both - habit, lack of awareness of prosthetic placement

transfemoral - weak residual limb musculature

Decreased Step Length Prosthetic Side: Prosthetic Cause

excessive socket flexion

Decreased Step Length Sound Limb/Decreased Stance Time on Prosthetic Limb: Non-Prosthetic Causes

pain in prosthesis

transtibial - decreased awareness, habit, knee or hip flexion contracture on prosthetic side, use of a walker

Decreased Step Length Sound Limb/Decreased Stance Time on Prosthetic Limb: Prosthetic Causes

ill-fitting socket

long prosthesis

Excessive Valgus or Varus Moment at the Knee: Non-Prosthetic Cause

ligamentous laxity

anatomical genu valgum or varum

Excessive Valgus or Varus Moment at the Knee: Prosthetic Cause

genu varum - lack of lateral tilt of socket or excessively inset (medial) foot

genu valgum - excessive lateral tilt of socket, or excessively outset (lateral) foot

both - ill fitting socket w/ wide ML dimensions

Where do Residual Limb Skin Issues w/ Excessive Varus occur?

proximal medial

distal lateral

Where do Residual Limb Skin Issues w/ Excessive Valgus occur?

proximal lateral

distal medial

Hyperextension Moment or Delayed Knee Flexion: Non-Prosthetic Cause

weak knee extensors

ligamentous injury

shoe selection w/ inadequate heel height

Hyperextension Moment or Delayed Knee Flexion: Prosthetic Cause

excessive PF of foot

lack of sufficient socket flexion

excessively soft heel (SACH foot)

prosthetic foot too far anterior

short prosthetic limb

Residual Limb Skin Irritation If Hyperextension or Delayed Knee Flexion Deviation Present

on the patella - pt may report excessive pressure on patella or posterior knee pain

How is excessive knee flexion characterized?

>10 degrees of knee flexion at heelstrike

When is excessive knee flexion described as drop off?

when it occurs from mid to late stance

Excessive Knee Flexion: Prosthetic Causes General

foot too far posterior relative to socket

excessive socket flexion

excessive foot DF

Excessive Knee Flexion: Prosthetic Causes Early Stance

heel too stiff

hydraulic ankle - foot PF control too tight

Excessive Knee Flexion: Prosthetic Causes Late Stance

soft DF bumper

hydraulic DF control too loose

keel too soft

Excessive Knee Flexion: Non-Prosthetic Causes

excessive heel height on shoes

weak knee ext

weak hip ext

knee flex contracture

Residual Limb Skin Issues w/ Excessive Knee Flexion

redness at ant distal and post prox

What does abducted gait look like?

can be observed in either TT or TF

widened BOS t/o gait cycle

Abducted Gait: Non-Prosthetic Causes

lack of confidence in prosthesis

dec balance

poor habit

too few socks --> loose socket fit

pain

unique to TF: compensation for weak hip abd, abd contracture, painful adductor roll

Abducted Gait: Prosthetic Causes

TT - short prosthesis, foot too outset

TF - too long, medial wall too high or pain, foot too outset, incorrect add angle

How is circumduction described?

excessive hip abd combined w/ wide arc of pelvis laterally during swing phase

Circumduction: Prosthetic Cause

long prosthesis

excessive PF

excessive swing resistance (hydraulic or microprocessor knee)

knee too posterior

socket too small

suspension poor

Circumduction: Non-Prosthetic Causes

too many socks

weak hip flex

poor timing

poor step thru on contralateral side

How is delayed pelvic rotation characterized?

lack or delayed ant rotation/translation of pelvis on prosthetic side

Delayed Pelvic Rotation: Non-Prosthetic Causes

poor coordination

weak pelvic stabilizers

hip flex contracture

What does delayed pelvic rotation result in?

poor swing phase including:

dec knee flex in swing

dec foot clearance

shortened step length on non-prosthetic side

How is excessive lordosis characterized?

inc ant pelvic tilt

hyperext of lumbar spine

Excessive Lordosis: Non-Prosthetic Causes

weak hip ext and abdominal mm

hip flex contracture

compensatory to inc stability of prosthetic knee

Excessive Lordosis: Prosthetic Causes

lack of socket flex

painful post wall of prosthesis

inadequate knee stability

How to define excessive rotation?

excessive ER of foot > 10 degrees

Excessive Rotation: Prosthetic Causes

ineffective socket contouring

socket too large

inappropriate foot choice

stiff heel

excessive toe out of prosthetic foot

inadequate suspension

Excessive Rotation: Non-Prosthetic Causes

weak hip IR/ext

inefficient WB on prosthesis 2/2 excessive UE support

improper donning

improper sock ply selection

Foot Drag: Prosthetic Causes

foot too PF

poor suspension --> pistoning

too long

knee too posterior

Foot Drag: Non-Prosthetic Causes

weakness of abd or PF on contralateral limb

too many socks

dec timing and coordination of hip and pelvis

poor stance phase w/ certain knees --> delayed or dec pelvic rotation, lack of WB thru prosthesis, short step length w/ contralateral limb

How is knee instability defined?

excessive knee flexion at IC to LR >10 degrees

Knee Instability: Prosthetic Causes

excessive DF

stiff heel response

socket doesn't accommodate for contracture

knee too anterior to TKA line

Knee Instability: Non-Prosthetic Causes

weak hip ext

hip flex contracture on prosthetic side

dec WB through prosthetic knee

short residual limb

Lateral Trunk Lean Toward The Prosthetic Side: Non-Prosthetic Causes

weak hip abd

hip abd contracture

pain on prosthetic limb

short TF residual limb

Lateral Trunk Lean Toward The Prosthetic Side: Prosthetic Causes

too short

foot too outset

medial wall of TF socket too high

socket places femur in too much abd

lateral TF socket wall doesn't provide adequate stabilization

Residual Limb Skin Irritation Noted w/ Lateral Trunk Lean Toward The Prosthetic Side

TT - prox lateral and distal medial lower leg

TF - ischial ramus, groin, distal end of femur

How is lateral whip defined?

prosthetic heel traveling laterally from midline during swing phase

Lateral Whip: Prosthetic Causes

knee too IR

socket too loose

foot too IR

foot too outset

foot too PF

toe lever too stiff

Lateral Whip: Non-Prosthetic Causes

improper donning

improper sock ply

weakness of hip ER

How is medial whip defined?

prosthetic heel traveling medial to midline in swing

Medial Whip: Prosthetic Causes

knee to ER on socket

foot too inset or ER

foot too PF

foot too stiff

loose socket

Medial Whip: Non-Prosthetic Causes

improper donning

improper sock ply

weak hip IR