FF - Prosthetic Gait and Orthosis

During a left-side amputation, where does the patient's COM need to move?

Toward the R side

If patient has there UE amputated, will COM move lower or higher?

Lower

If patient has a bilateral amputation, where would COM be?

Middle but will go higher

n an above-knee prosthesis, what do low walls generally indicate?

Weak muscles

What does a low anterior thigh wall indicate?

Weak quadriceps

What does a low lateral wall indicate?

Weak hip abductors

In an above-knee prosthesis, what do high walls generally indicate?

Tight muscles

What does a high anterior thigh wall indicate?

Tight hip flexors

What pelvic position can result from tight hip flexors?

Anterior pelvic tilt

Why does a high anterior thigh wall relate to anterior pelvic tilt?

Tight hip flexors pull the pelvis into anterior pelvic tilt.

What prosthetic problems can cause lateral bending during stance?

Short prosthesis or inadequate lateral wall

What prosthetic problems can cause abduction during stance?

Long prosthesis or hip joint fixed in abduction

What prosthetic problem can cause lordosis during stance?

Anterior socket wall discomfort

What prosthetic problems can cause forward flexion during stance?

Unstable knee joint or short walker

What prosthetic problem causes early swing/high heel rise?

Slack extension aid

What prosthetic problem causes late swing/terminal impact?

Taut extension aid

(taut = termination)

What prosthetic problems can cause a heel whip?

Knee bolt rotated or prosthesis donned in malrotation

What prosthetic problems can cause foot rotation during heel contact?

Stiff heel cushion or malrotated foot

What happens when plantarflexion is restricted by a stiff heel cushion or hard plantarflexion bumper?

The knee may need to flex more than normal to allow the sole of the foot to reach the floor

What happens when a hard plantarflexion bumper does not absorb heel-strike impact?

It produces abrupt and excessive knee flexion

A prosthetic heel cushion is too stiff. What is the expected knee response?

Excessive knee flexion during early stance

What happens with a too-soft heel cushion or soft plantarflexion bumper?

The heel cushion has excessive compressibility

With a heel cushion that is too soft, where does the ground reaction force (GRF) pass relative to the knee?

Anterior to the knee between heel strike and mid-stance

What does an anterior ground reaction force relative to the knee cause?

Knee hyperextension

In orthotic gait, inadequate assist is similar to what?

Weak muscles

In orthotic gait, inadequate stop is similar to what?

Spastic muscles

Weak dorsiflexors are analogous to what orthotic problem?

Inadequate dorsiflexion assist

Plantarflexor spasticity is analogous to what orthotic problem?

Inadequate plantarflexion stop

What gait deviations can result from inadequate dorsiflexion assist?

Toe drag, circumduction, hip hiking, and vaulting

What gait deviations can result from inadequate plantarflexion stop?

Toe drag, circumduction, hip hiking, and vaulting

Function of a posterior leaf spring AFO

Assists with dorsiflexion during swing

What happens to the posterior leaf spring during early stance?

Bends backwards

What happens to the posterior leaf spring during swing?

Recoils to help lift the foot into dorsiflexion

Function of Klenzak AFO

Dorsiflexion spring assist AFO

When should a Klenzak AFO be avoided?

With spasticity

What does a posterior stop AFO limit?

PF

What does a posterior stop AFO help prevent during swing?

Toe drag

What does a posterior stop AFO help prevent during early stance?

Knee hyperextension

What does an anterior stop AFO limit?

DF

Who may benefit from an anterior stop AFO?

Someone with triceps surae paralysis

What does an anterior stop AFO help achieve?

Propulsion during late stance

What does a solid AFO limit?

All foot and ankle motions

What does a hinged AFO allow?

Slight sagittal-plane motion

What does the hinged AFO facilitate during early stance?

Progression to foot-flat

What does the anterior pin of a Bichannel Adjustable Ankle Locks (BICAALs) do?

Limit Dorsiflexion

What does a posterior pin limit?

PF

What does an anterior spring cause in BICAALs do?

Plantarflexion

What does a posterior spring cause?

DF

What does a spiral AFO limit?

All movements

When is a spiral AFO contraindicated?

With moderate-to-severe spasticity or edema