Exam 4: Orthotics Part 3, AFOs, KAFOs, HKAFOs Flashcards Preview

Bringman class fall 2015 > Exam 4: Orthotics Part 3, AFOs, KAFOs, HKAFOs > Flashcards

Flashcards in Exam 4: Orthotics Part 3, AFOs, KAFOs, HKAFOs Deck (64):

6 types of AFOs that are not what was in the last deck (don't know how to ask this question, maybe just mark it blue and get rid of it)


  1. Anterior Floor Reaction AFO
  2. Patellar Tendon-Bearing/Total Contact/Claim Shell AFO (book called it Weight Relieving AFO)
  3. Posterior Leaf-Spring AFO
  4. Spiral AFO
  5. Klenzak
  6. AFO's with Joints


What dos an Articulating/Dynamic AFO do (very general)?

It allows or assists motion


Anterior Floor Reaction AFO

  • What is it/what does it look like?
  • What does it do?
  • What it is used for? (2)

Anterior Floor Reaction AFO (Pg 229)

  • big chunk of plastic in front
    • limits tibial translation (and dorsiflexion), which promotes knee extension (keeps knee more extended)
  • Often used for people with people with crouch gait (gait seen in Parkinson's) 
  • Could use with knee buckling


Patellar Tendon-Bearing AFO?

  • What is it/what does it look like?
  • What does it doe?
  • What might it be used for?

Patellar Tendon-Bearing AFO

  1. Total Contact along front
  2. Reduces the axial load of the distal limb and puts it on the tissue of leg and patellar tendon
    • takes weight bearing from distal end of extremity and distributes it higher up
  3. Used for
    • Ulcer
    • non-union of fracture

**Not used very often now

**Alternate Names: Total Contact- or Clam Shell- AFO (three different names he gave for the same thing) (called Weight-Relieving AFO in book, pg 230)


What are the 2-3 alternative names for a Patellar Tendon-Bearing AFO?

  1. Total Contact AFO
  2. Clam Shell AFO
  3. Weight-Relieving AFO (book's term, Dr. Bringman did not mention it)


Posterior Leaf-Spring AFO

  • What is it/what does it look like?
  • How does it work?
  • What is it good for and 2 advantages?

Posterior Leaf-Spring (pg 232)

  • Considered articulating/dynamic even though it has no joints (but it moves and stores and releases energy)
  • Like rigid AFO, but doesn’t provide mediolateral stability since side trimlines are removed (so it is just relatively thin in the back)
  • Allows more ankle rocker motion, and assists with spring into dorsiflexion at toe off (I think it returns from DF toward PF and then stops at neutral)
  • Stores energy and provides small assist with recoil
    • Will slow PF, allow DF a bit in stance, and then assist launch (but not allow DF)
  • Good for foot drop
  • Low visibility, and fits in shoes pretty well

**Not used as much now because of the Spiral AFO


What are the two types of Klenzak AFO?



Double Klenzak



What is another name for the Double Klenzak AFO?



True/False: Klenzak or Double Klenzak (BICAAL) don't have to be on an all-metal AFO. They can also be found on a plastic AFO.


Klenzak or Double Klenzak referrs to the joint mechanism, so it can be incorporated in a plastic or metal AFO


What is the difference between a Klenzak and a Double Klenzak (BICAAL or Bichannel)?


Klenzak has one channel (picture on pg 237, figure 9-18)

  • Channel runs diagonal anterior/superior and posterior/inferior to joint

Double Klenzak has two channels (picture on pg 236, figure 9-17)

  • 2 parallel channels running vertical

    • one anterior to joint

    • one is posterior to joint

**Picture is of a Klenzak


Describe a (plain) Klenzak

  • What does it look like?
  • How does it work?


  • 1 channel runs diagonal from superior/anterior to inferior/posterior to the joint
  • in these channels you can put one of two things in it
    • rod
      • makes it a solid AFO
    • spring
      • it will assist with dorsiflexion, just like a spiral AFO
  • When a person comes into initial contact to loading, the foot goes flat and the spring gets tension on it (gets squished).
  • Spring stays squished during loading response.
    • The spring is in the channel running superior/anterior to inferior/posterior, so it is coiled tightly when foot is in PF.
  • The coil is the tightest at toe off (Dr. bringman said this).
  • When foot lifts off after toe off, the spring releases and pushes heel down, causing toe to come up.  

**The way it works is weird and people get really confused. Probably look it up again in the book until you understand.


Double Klenzak/BICAAL/Bichannel Klenzak:

  • What is it/what does it look like?
  • How does it work?

Bichannel is on pg 236

  • 2 parallel channels running vertical (one anterior to joint; one is posterior to joint)

  • It is adaptible

    • you can put rods or springs in each channel

    • If you put rods in both channels, the AFO will be locked in neutral
    • If you put a spring in the anterior channel, it could assist PF (but that is rarely used I think)
    • If you put a spring in posterior channel, it will help with DF
    • Take out all the rods or springs and it will provide only mediolateral stability
      • or leave both springs in there to assist with both PF and DF while providing mediolateral stability

**this can be confusing, recommend looking in book or looking for more info until you understand it


Why is it good to have AFOs with joints?

we don’t want to cause atrophy by restricting movement when a pt has some strength for a movement that would be allowed by an AFO joint


Four types of AFO joints

  1. Overlapping plastic to create a joint
  2. Oklahoma AFO (it is the type of joint in the AFO that makes it an Oklahoma)
  3. Gillette
  4. USMC


Three things about a plastic overlaping joint

Overlapping plastic to create a joint

  • Two pieces of plastic overlap
  • needs padding
  • provides lots of stability

Couldn't find a good picture (Dr. brinman showed us one though)


Spiral AFO

  • What is it/what does it look like?
  • How does it work?
  • What is it for?


Spiral AFO (figure 9-14 on pg 234), Discussion is under Commercially Available DF Assist Designs

  • A carbon fiber orthosis that provides dorsiflexion assistance at the appropriate times in the gait cycle.
  • Straps to front of tibia and  spirals around to attach to full foot plate
  • Allows and supports similar movement to the leaf spring AFO, but fits in a shoe better
    • Often fits in normal shoe size by putting it under the insole
  • Very lightweight
  • Deforms and springs back to neutral at various points in the gait cycle
  • Common for foot drop now (has mostly replaced the Posterior Spring Leaf)


Oklahoma AFO?

  • what is it/what does it look like?
  • what is it for?

  • often used when we start with solid AFO, but we think a pt may need joints when they improve in the future
  • The solid AFO is made with a place for the Oklahoma joint to be installed later
  • If the joint wears out, we can replace it
    • The joint is a removeable


Gillette Joint

  • What is it/what does it look like?
  • What is it for?

Gillette (pg 235)

  • Made out of a flexible material that bends (not a true articulating joint)
  • wears out very quickly! (Dr. Bringman doesn’t have any that are not broken)
  • Used only in pediatrics


USMC joint

  • What is it/what does it look like?
  • how does it work?

  • Has a disk in the joint which allows different available degrees of motion (like a knee orthosis)
  • different disk shapes change available degrees of motion

**not in the book

**Dr. Bringman has one for us to look at (I couldn't find a picture that I was sure was the right one)

**Dr. Bringman said he thought the name stood for United States Marine Corps (but I can't figure out if he was joking)


Four things to know about stops used in articulated AFOs:



  • usually a plantar flexion stop is used
  • limits one motion but allows another
  • Some change the amount of motion we limit (a peg that skrews in and out)
  • Sometimes just an itty bitty bit of foam we stick there


Three Reasons to make a KAFO

Reasons for KAFO

  • If knee buckling cannot be controlled by AFO
  • Genu varus
  • Genu valgus

KAFOs (start on pg 239)

If for some reason we cannot control the knee at the ankle, then we move up a joint, understanding that we are now going to add a lot of weight to the orthosis and pt. Requires a lot more energy expenditure and clothings options become more difficult, cosmesis goes out window, and it costs more.


What are the vast majority of KAFOs for?


Vast majority of KAFOs is going to be to stop knee buckling

(most of the time we can control recurvatum at the ankle)


How does the KAFO control Genu valgum and Genu varum?

Genu varum Genu valgum pretty simple to think about

  • rods going up sides (uprights that pretty much take the place of our ligaments)
  • Need enough contact above and below to hold in place and provide stability
  • The KAFO knee joint must be in pretty much in exact alignment with the knee axis. (mimic and follow the exact movement of the knee) It MUST stay in the right place.
    • shoot for the middle of the traveling knee axis
      • For most of gait, the axis doesn’t move that much.


If the KAFO joint axis is exactly aligned with the knee joint axis, what is the most likely condition the KAFO is supporting?

Genu Varum or Genu valgum

(for buckling there would be a posterior offset)


Explain how to position the KAFO to prevent knee buckling and how it works

What might be a draw back?

Prevent buckling (use posterior offset with locking)

  • Offset the orthosis joint at knee ever so slightly posterior to keep someone from buckling
    • it becomes their new knee joint
    • We want to keep them in extension
    • If we put the brace joint slightly posterior it allows GRF to exert extension force on the brace joint more quickly, (which in turn might put some extensor force on knee, but what we really care about is the brace joint because pt is now weight bearing through the KAFO)
  • it might interfere with other parts of the gait cycle, but it prevents them from falling down.


True/False: The ankle part of all KAFOs must be locked, to prevent articulation at the ankle.


The ankle can have a locked or articulating joint depending on the pt needs.


What condition wil most KAFOs that lock at the knee be for?

Knee buckling

(but there must be a way to unlock them to be able to sit)


What would you do in a KAFO to correct recurvatum caused by spacticity (ankle is fine)?

  • Use Non-locking knee joint set in neutral on a KAFO or KO (non-locking Knee joint)
    • Set knee brace at neutral (put a block, so it won’t extend past neutral)

**What we do with the ankle really depends on the pt, but if we lock at the knee we may allow more ankle movement.


What are locking KAFOs usually for?

usually for pts with knee buckling


What are 4 types of locks that can be used in a KAFO?

  1. Simple Drop Locks
  2. Ball Bearing Drop Locks
  3. Bail Lock KAFO
  4. Spring Loaded Drop Lock


What is a 5th type of KAFO where the knee is locked?

Scott-Craig KAFO


KAFO: Simple Drop Locks

simple drop locks

  • not that advantageous for someone using their KAFO all the time by themselves.
  • Might be used just in PT (PT unlocks and make sure they lock)
    • Pt with SCI that insurance doesn’t think is going to really walk again, but it is therapeutic to stand.


Scott-Craig KAFO

  • A type of KAFO often used with pts with SCI where the knee is always locked and the pt is encouraged to use the Y ligament of the hip to "hang" in to stay standing
  • If you have them on bilaterally, then you will have a spreader bar to keep feet from going on top of each others after swing through.
  • Pt will use assistiive device


Ball Bearing Drop Lock

Ball Bearing Drop Lock

  • like simple drop lock, but you must push the lock down (the ball bearing keeps it from falling down)
  • Still need fine motor skills, but easier to do one side at a time
  • Pt that is buckling, want to put them in a slightly posterior orthosis joint
    • We put them in ball bearing drop lock, so in therapy PT can leave the locks up to help with gait training while the PT is there. Or if they are having a bad day you can lock it
    • But when in other situations, they can lock it.
  • Could be good for someone that has varying function as part of their disease process
    • Stroke
    • MS


Bail Lock KAFO

Bail Lock KAFO

  • Lever loop on the back of the thigh that will lock and be unlocked.
  • Not the best thing for if you are around a lot of people that could bump into the lever


Spring Loaded Drop Lock

Drop lock that cannot be disengaged unless someone pulls the cord (like on a parachute)


How does KAFO Compromise the gait cycle (especially when it is locked) (5 things)

KAFO Compromises of the Gait Cycle (locked knee in swing)

  • Gives us great control in stance phase with the compromise of swing phase.
  • Slow gait
  • Uses tons of energy
  • Stairs Compensation
    • Step-to with the contralateral leg leading up (up with the unaffected, down with the affected)
  • Slopes and hills
    • hard, but doable if they do switchback
    • Keep affected leg down


What are some compensations for gait with locked KAFO?

  • Regular gait (3)
  • Stairs
  • Slopes/hills

Compensations (regular gait)

  • hip hike
  • circumduction
  • Vault

Stairs Compensation

  • Step-to with the contralateral leg leading up (up with the unaffected, down with the affected)

Slopes and hills

  • hard, but doable if they do switchback
    • Keep affected leg down


Explain why proximal trim line could be a concern in a KAFO

(include compensations you might see)

proximal trim line height

  • could dig into inguinal space
    • will make gait cycle painful during stance phase
    • will discourage weight bearing
      • decreased stance time
      • short contralateral step length
      • Cause trunk lean to or from pain in inguinal space
      • (think about all the ways someone might compensate)


What is a condition that could cause recurvatam that requires and AFO with more dorsiflexion (Fixed AFO with 0-5* DF)?

Extension Spacticity (but not so bad that skin breakdown is a major concern)

Quads and Gastroc pushing knee into recurvatum (Gastroc crosses two joints, and in close chain will pull knee back)


DF helps reduce strength of spasticity, and the AFO also resists the person from going into extension.


What are the materials that KAFOs could be made from?

Same as AFOs

  • Metal
  • Plastic
  • Leather (straps)
  • Velcro (straps)
  • Foam/padding


True/False: you should instruct your patients who wear a KAFO to wear legging underneath in order to protect the skin like socks do for AFOs


  • Metal KAFOs with straps are often worn outside the clothes
  • Plastic are often worn under the clothes
    • don’t usually have to put sock up to groin (or use leggings), can allow contact with skin


What type of material may you add to a KAFO for someone with really bad knee buckling?

may add a patellar pad for someone who has really bad knee buckling


You should consider strapping vs plastic and comfort when deciding which materials to use in a KAFO.

you're welcome

(didn't think of a good way to ask that, but wanted to share info)


True/Fales: There is great literature that HKAFOs lead to functional community ambulation in adults?


It is just the opposite


How does the pediactric version of an HKAFO and an adult HKAFO compare?

  • Pedes version is tiny and light
  • Adult version is very cumbersome
    • to don and doff especially


Where is the joint axis at the hip for a HKAFO?

Its hard to remember where our joint axis is

  • We use the greater trochanter as a landmark
    • actual axis is slightly superior and anterior to greater trochanter


How does an HKAFO affect motion in gait?

Once you lock out a hip, motion is going to be limited to swing through (see picture)

  • there is a lot more in the book, he is not going to kill us with


What should you look for under the part of the HKAFO that comes up around the waist?

skin break down!


True/False: HKAFOs could help a child progress to walking?


but they are mostly worn during PT sessions, not all the time

(I think)


When might we use a HO?

for someone who had a hip replacement that has dislocated

**Atrocious to work with


What are four types of HKAFOs?

  • Standing frame
  • RGO (reciprocal gait orthosis) and
  • HGO (hip guidance Orthosis)
  • Parapodiums

**I think he reccomended we remember the RGO and HGO as two names for basically the same thing


How do HGO/RGO work?

Hip guided Orthosis and Reciprocal Gait Orthosis (pg 257)

  • work differently, but have same result
  • RGO is By weight shifting and loading one leg the spring loaded cables advance other limb slightly forward (RGO Is in picture).
  • He showed videos of these being used by pts with paraplegia and quadreplegia.


Standing Frame HKAFO

Standing frame looking thing used for pediactrics in PT sessions

  • progress to parapodium (ORLAU) when child keeps rocking and starting to move




Called Orthotic Research and Locomotor Assessment Unit (ORLAU in the book, but Dr. B said to just call it a parapodium

A progression for pediactric from a standing frame:

Child shifts wieght back and forth and the moving the little blocks allows them to do shuffle steps


What should we remeber when studying types of orthotics for this test

When studying remember how much time he spent on each of these types of orthotics. Number of questions will be proportional to how much time he spent on each thing.

(I think he mentioned like 1 question for HKAFOs? Not sure if he will actually do that)


Pt with AFO shows hip hike, on orthotic side during swing phase. What could be the problem with the AFO?

  1. Too much PF
  2. Proximal trim line too high (limits knee flexion)


Pt with AFO shows hip hike, on orthotic side during swing phase. What could be wrong with wearer?

  1. leg length difference
  2. could just be used to hip hike
  3. could be weak hip flexors/knee flexors


Client in AFO, knee instability and buckling in stance phase. What is the problem with the orthotic?

Too much dorsiflexion


Client in AFO, knee instability and buckling in stance phase. What could be a wearer problem?

  1. weak quads (99% of the time)
  2. Knee flexion contracture
  3. hamstring/tib ant spasticity (knee flexor spasticity) - very uncommon
  4. weak gastrocs (allows tibial translation)


Client in AFO shows excessive DF in midstance on AFO side. What could be the AFO problem?

  1. Set in excessive DF?
  2. AFO is too short (proximal trim line is too short)
  3. Proximal strap is too loose


Client in AFO shows excessive DF in midstance on AFO side. What could be the wearer problem?

  • weak quads (99% of the time)
  • Knee flexion contracture
  • hamstring/tib ant spasticity (knee flexor spasticity) - very uncommon
  • weak gastrocs (allows tibial translation)
  • crouched gait


Pt wearing KAFO. Shows knee instability on Midstance. What could be the orthotic problem?

  • KAFO joint set too anterior (should be posterior)
    • GRF anterior to joint line sooner
  • Need a locking KAFO


Pt wearing KAFO. Shows knee instability on Midstance. What could be the wearer problem?

  • weak quads (99% of the time)
  • Knee flexion contracture
  • hamstring/tib ant spasticity (knee flexor spasticity) - very uncommon
  • weak gastrocs (allows tibial translation)
  • crouched gait