S2 L7: Ankle Foot Orthosis (AFO) Flashcards
What are the components of AFO?
- Foundation: the shoes/base
- Ankle Control
- Foot Control: used in cases when the pt has valgus or varus
- Superstructure: entire skeleton of the orthosis
What are the main advantages of the Insert Foot Plate?
- Provides good control of the foot
- There are AFOs used as the shoe itself; there are also inserts/footplate
- Permits interchanging shoes
- Lightweight
- Limit footdrop
What are the disadvantages of Insert Foot Plates?
- Reduces interior shoe volume = tighter fitting shoe
- More expensive
U-shaped fixture, the center is riveted to the shoe through the shank; holds the shoe underneath
Stirrup
Arms of the stirrup join the brace uprights at the level of _____, providing _____ between orthotic and anatomical joints
- The anatomical neck
- Congruency
Ankle control that holds foot to 90° (neutral), assists during heel strike; indicated for patients with DF weakness / foot drop d/t common peroneal n. impingement
Posterior Leaf Spring
How to checkout the Posterior Leaf Spring?
- Posterior shell is behind the malleoli (malleoli are free)
- Proximal shell is at midpart of the leg
- Distal part should not extend toes
- Only extend up to metatarsal shafts (there’s a primary basis for this)
This ankle control is a DF spring assist; Coil spring compresses in stance and rebounds during swing
Klenzak Joint
The ankle control that tends to impose a flexion force at the knee during early stance and prevents the lax knee from hyperextending or moving posteriorly
PF Resistance (Posterior Stop)
For the PF Resistance: If the stop is set to allow slight PF of ~ 5°…
Knee extension results which can be used to control an unstable knee that buckles.
Active Knee Flexion = ???
Passive DF
Active Knee Extension = ???
Passive PF
5° of PF using PF resistance = ???
Genu Rectuvarum
Too much PF causes…
Severe knee recurvatum or foot drop
Anterior stop that aids individual with paralysis of the tricep surae to achieve late stance
DF Resistance
If the DF Resistance is is set to allow slight DF of ~ 5°, knee flexion results, can be used to:
Control Hyperextension
Too much DF results to:
Knee buckling (flexion when WB or instance) results
Orthoses that limits all foot and ankle motion
Solid AFO
Where is the trimline of the Solid AFO and what is its purpose?
Trimline: Anterior to Mammeoli
Purpose: Immobilize entire ankle and restrict foot drop
To which pts is the Solid AFO indicated?
Hemiplegia and Spastic Diplegia
This orthoses can be adjusted whether you want DF or PF which allows for controlled mobility
Bi CAAL
Identify the Function and Clinical Indication for the corresponding Channel and Pin: POSTERIOR PIN
Function: Limits plantarflexion
Clinical Indications: Plantar spasticity, toe drag, pain with ankle motion
Identify the Function and Clinical Indication for the corresponding Channel and Pin: POSTERIOR SPRING
Function: Assists dorsiflexion
Clinical Indication: Flaccid footdrop, knee hyperflexion
Identify the Function and Clinical Indication for the corresponding Channel and Pin: ANTERIOR PIN
Function: Limits dorsiflexion
Clinical Indication: Weak plantarflexors, weak knee extensors, pain with ankle motion
Identify the Function and Clinical Indication for the corresponding Channel and Pin: ANTERIOR SPRING
Function: Assists plantarflexion
Clinical Indication: None
T/F: In a Bi CAAL, you cannot combine a pin and spring posteriorly or anteriorly.
False. You can!
This foot control (AKA Medial T Strap) arises from the shoe quarter covering the medial malleolus and buckles to the lateral upright, pushing laterally.
Valgus Correction Strap
In a Valgus Correction Strap, it exerts a _____ force to restrain _____.
- Laterally directed
- Pronation (Valgus)
This foot control (AKA Lateral T Strap) arises from the shoe quarter, covers the lateral malleolus, and buckles to the medial upright, pushing medially.
Varus Correction Strap
The Lateral T Strap buckles around the medial upright, corrects _____ (_____ _____)
- Varus
- Hindfoot Supination
A low-profile supramalleolar design for a subtalar joint control to limit varus or valgus.
Supramalleolar Orthosis (SMO)
It is the proximal part of the orthosis or weight relieving orthosis.
Superstructure
Parts of the Superstructure
Uprights & Shell/Band/Brim
Superstructure that winds around the calf and controls but does not eliminate motion in all places.
Spiral AFO
To whom are Spiral AFOs indicated?
Pts who are active
Superstructure that reduces the amount of weight transmitted to the foot (d/t foot pain, ankle conditions) to the patella during amb
Patellar-tendon-bearing Brim
Superstructure that ends beyond the toes to counteract severe PF spasticity
Tone Reducing Orthosis
Plastic AFOs (Tone Reducing Orthosis) is designed for children with _____ and adults with _____.
- Spastic CP
- Spastic Hemipelgia
Tone Reducing Orthosis Footplate: Design, Purpose, Application
Design: Broad and upright
Purpose: Modify reflex hypertonicity
Application: Constant pressure to the PFs and invertors to control the tendency of the foot to assume equinovarus posture
To whom are the Tone Reducing Orthosis indicated for?
Pts who have mod spasticity with varus instability, but do not have fixed deformity
