Metal AFO

Question 1

Solid Ankle

Answer 1

Functional Deficit: Significantly decreased strength in anterior and posterior musculature; Pain at ankle

Direct Effects: Swing Phase- Foot clearance
Stance Phase- Protect calf musculature from sudden stretch

Indirect: Stance Phase- Provide knee stability- prevent both buckling and hyperextension; Possibly decreased compensations at hip by
creating better foot clearance

Question 2

Limited Motion

Answer 2

Functional Deficit: Decreased strength
in anterior or posterior musculature- amount of motion allowed impacted by amount of strength; Pain at ankle

Direct: Swing Phase- Foot clearance
Stance Phase- Protect calf musculature from sudden stretch

Indirect: Stance Phase- Provide knee stability- less stability than a solid, amount of movement allowed decreases level of brace control at knee; Possibly decreased compensations at hip by
creating better foot clearance

Question 3

Plantarflexion Stop

Answer 3

Posterior channel ball, pin, screw

Functional Deficit: Decreased strength in the anterior musculature

Direct: Foot clearance in swing

Indirect: Stance Phase- Control for knee hyperextension; Possibly decreased compensations at hip by creating better foot clearance

Question 4

Dorsiflexion Stop

Answer 4

Anterior channel ball pin, screw

Functional Deficit: Decreased strength in posterior musculature

Direct: Stance- Prevents rapid tibia progression as
transition from heel strike to midstance (therefore)- prevents overstretching of calf musculature

Indirect: Control rapid knee flexion after heel strike moving to mid stance

Question 5

DF Assist

Answer 5

• Caution with Spasticity
  posterior channel ball, spring, screw

Functional: Decreased anterior musculature strength in the presence of good or stronger
gastric-soleus strength

Direct: Swing Phase- Improved foot clearance during swing
Stance Phase- Eliminates foot slap at heel strike

Indirect: Eliminates/decreases compensations at hip by clearing better foot clearance

Question 6

PF Assist

Answer 6

*Caution with spasticity
Anterior channel ball, spring, screw

Functional Deficit: Decreased posterior musculature strength in the presence of strong anterior musculature strength (rarely used)

Direct Effects: Stance Phase- Possible assistance for standing balance Possible assistance for foot control for push off

Question 7

Free Motion

Answer 7

Functional Deficit: Decreased eversion or inversion strength; Pain at ankle

Direct Effect: Coronal plane stability at ankle; no
impact on sagittal plane movement/control

Question 8

DF stop, PF stop, DF Assist

Answer 8

Anterior: Ball, Pin, Screw- length of pin or
how far screw is tightened is dependent on wanted range
Posterior: Ball, Narrow Pin, Spring Screw- screw all
the way down

Functional Deficit: Significantly decreased strength in anterior and posterior musculature

Direct: Swing Phase- Foot Clearance; may get more clearance with spring as compared to limited motion
Stance Phase- Protect calf musculature from sudden stretch

Indirect: Stance Phase- Provide knee stability- less stability than a solid, amount of movement allowed decreases level of brace control at knee; Possibly decreased compensations at hip by creating better foot clearance

Question 9

KAFO with solid ankle

Answer 9

Close anterior and posterior channel
Functional Deficit: Significantly decreased/absent
strength in anterior and posterior musculature at ankle and knee

Direct: Swing Phase- Foot Clearance
Stance Phase- Protect calf musculature from
sudden stretch Maintain knee extension in stance

Indirect: As long as angle correct-
Swing Phase- Use of spreader bar and ankle DF increase ease of swing through gait

Stance Phase- Ground Reaction force assists hip extension so patient can hang on anterior ligaments of hip (Y Ligament of Bigalow) to maintain hip extension in the absence of hip extensor strength