AFOs

How does a posterior leaf spring AFO behave during early stance?

It bends backward.

What is the primary function of a posterior leaf spring AFO during the swing phase of gait?

It recoils to lift the foot, assisting with dorsiflexion.

What is the rule regarding modifying the material rigidity of a posterior leaf spring AFO?

Material can be removed to weaken the spring, but material cannot be added to increase rigidity.

What effect does a posterior leaf spring AFO have at heel contact regarding knee control?

It offers slight plantarflexion to prevent knee flexion.

What degree of medial-lateral stability is provided by a posterior leaf spring AFO?

None; it offers no medial-lateral stability.

How is the tension or tightness adjusted on a dorsiflexion spring assist (Klenzak) AFO?

Via a screw located on the steel spring in the ankle stirrup.

How does the spring in a Klenzak AFO function during stance and swing phases?

It compresses during stance and rebounds during the swing phase.

Which is considered to be more bulkier: Klenzak or Posterior leaf spring

Klenzak

At what point does of the gait cycle does the Klenzak provide plantarflexion

Heel contact

Why should a dorsiflexion spring assist (Klenzak) AFO be avoided in patients with spasticity?

The quick spring stretch/rebound can trigger or exacerbate hyperactive stretch reflexes and spasticity.

Which ankle movement is restricted by a posterior stop AFO?

Plantarflexion

How does a posterior stop AFO assist gait during the swing phase?

It prevents toe drag.

How does a posterior stop AFO influence knee mechanics during early stance?

It imposes a flexion force at the knee, preventing knee hyperextension.

Which ankle movement is restricted by an anterior stop AFO?

Dorsiflexion

Which patient impairment benefits from an anterior stop AFO to aid propulsion during late stance?

Paralysis of the triceps surae.

Where are the trimlines located on a standard solid AFO relative to the malleoli?

Anterior to the malleoli.

What degree of foot and ankle motion is restricted by a solid AFO?

It limits all foot and ankle motion.

How is a hinged AFO constructed from a solid plastic AFO design?

The solid AFO is divided transversely at the ankle, connecting the two sections with a hinge.

What gait advantage does a hinged AFO offer over a solid AFO during early stance?

It permits slight sagittal motion, facilitating progression to the foot-flat position.

In a bichannel adjustable ankle lock (BICAAL), what general roles do pins and springs serve?

Pins limit movement, whereas springs assist movement.

What is the function of a pin/peg placed in the anterior channel of a BICAAL AFO?

It limits dorsiflexion.

What is the function of a pin/peg placed in the posterior channel of a BICAAL AFO?

It limits plantarflexion.

What motion is assisted by placing a spring in the anterior channel of a BICAAL AFO?

Plantarflexion

What motion is assisted by placing a spring in the posterior channel of a BICAAL AFO?

Dorsiflexion

What motion limitation is imposed by a spiral AFO?

It limits all foot and ankle movements.

What are two key contraindications for using a spiral AFO?

Moderate to severe spasticity or edema.