Test 2: AFOs Flashcards
some purposes of orthotics in general
improve performance of functional activities
improve/enhance mobility (i.e. amputation)
prevent deformity
correct passively modifiable deformity
immobilization/control/prevention
regulate/reduce muscle tone
stabilize weak/flaccid muscles
improve quality of life
describe the three point (counter force) system
includes middle force and 2 end forces
prevents plantar flexion and inversion
characteristics of metal AFOs
strong
heavy
doesn’t work well if volume fluctuates
characteristics of thermoplastic AFOs
conforms to body when custom fitted
lightweight
easy to mold
characteristics of composite material AFOs
thin
strong
durable
store and release energy
ways to restrict movement to different degrees
how enclosed the AFO is
more material = more control
describe a free ankle joint
no control
can go through full ROM in designated plane
provides some medial lateral stability
describe ankle joint with assist
plantar flexion assist most common
assists motion using external force
how does a dorsiflexion assist AFO work
uses a spring or elastic to help with DF
how does a dorsiflexion plantar flexion assist (dual channel) or bi channel ankle locks (BiCAAL) work
joint with anterior and posterior spring that assiste with plantar and dorsiflexion to varying degrees according to settings of the spring
describe a plantar flexion stop
restricts PF but allows DF
describe a dorsiflexion stop
restricts DF but allows full PF
what is a limited stop motion AFO
limits or stops joint movement
can set specific ROM restrictions
describe the cinical decision making process for selecting an AFO
- identify impairments- location/type/joints
- functional goals- PLOF, prognostic, disease progression
- orthotic goals - type of impairment relates; stabilize, protect, correct, etc
- possible orthotic solutions to meet goal - biomechanical features
- develop orthotic prescription - most appropriate device for pt
factors to consider with orthotic Rx
effective but least controlling
limit interference woth normal movement of adj joints
energy efficiency
foces on adj joints
minimize negative side effects
pt satisfaction/ease of use
how does DF paresis compensate
steppage gait
increase hip and knee flexion in swing
how does DF paresis impact spactial temporal factors of gait
decreased step length
decrease time to foot flat
how does PF paresis compensate
increase stance knee flexion
increase stance phase DF
how does PF paresis affect temporal spatial parameters of gait
prolonged midstance
decrease stance time
prefabricated vs custom AFOs
prefabricated
- off the shelf
- generic fit
- size selection
- more accessible
- quicker/cheaper
custom
- specific to pt
- need orthotist
- more expensive/takes more time
functions of a solid or fixed AFO
stance stability (ROM impeded, especially with SLS)
ML support
assists with foot clearance
position foot for initial contact
blocks DF and PF
how to fit an AFO to avoid knee hyperextension
align the AFO into more DF = prevent hyperextension
opposite of patient is staying in too much knee flexion
negative impact of solid AFO
cant go into DF with:
- sit to stand
- stairs
- walking up/down hill
functions of hinged/articulating AFOs
allows for ankle ROM- depends on PF or DF stop
provide ML stability
can have DF assist
aids in foot clearance
describe metal upright articulating AFOs
utilize bichannel adjustable ankle locks (BiCHAALs)
highly adjustable to limit and/or assist ankle motion
can be for DF assist with PF stop or PF assist with DF stop
describe posterior leaf spring
flexible thermoplastics
trimline posterior to malleoli; doesnt provide much ML support
functions of posterior leaf spring
control PF from initial contact to loading response
allows for DF during stance
support foot during swing
what does a posterior leaf spring not work well for
individuals with moderate to severe hypertonicity
metal upright articulating AFOs dont work well for
those with limb volume fluctuations
abnormal foot position
anterior floor reaction AFOs are not appropriate for
individuals with knee ligamentous instability or genu recurvatum
functions of anterior floor reaction AFOs
maintain proper ankle alignment
compensates for weak or absent gastroc soleus muscles
facilitate plantar flexion knee extension couple
anterior shell controls forward tibial progression
what are the coupling movements for the knee and ankle
DF and knee flexion
PF and knee extension
describe energy return or dynamic response AFOs
typically made of carbon fiber
inappropriate for individuals with moderate to severe hypertonicity
functions of energy return or dynamic response AFOs
assist limb clearance in swing
position heel for initial contact
assist with forward propulsion
what is the rancho ROADMAP
recommendations for orthotic assessment, decision making, and prescription
what is a factor that can indicate a pt needs an orthoses more involved than an AFO
if the pt has <3+/5 quad strength or impaired proprioception on test limb
what types of AFOs does medicare cover that are not used during ambulation
PF contracture
reasonable expectation of ability to correct contractire
contracture interferes with functional abilities
uses a component of therapy program, including active stretch
plantar fasciitis
what are reasons AFOs are covered by medicare when used during ambulation
individuals with weakness or deformity of the foot and ankle who:
require stabilization for medical reasons
have potential to benefit function
advantages of functional electrical stimulation, FES and how it works
cosmesis
less bulky
less restrictive
rely on stimulating common peroneal n (anterior tibialis)
sensor used to detect lower leg position
describe the ossur foot up
light weight
easily adjusted
low maintenance
affordable
must be used with shoes
assists with foot clearance
benefits of AFOs for adults with hemiplegia
prevent or reduce PF or IV contractures
improve balance
enhance gait
reduce genu recurvatum if PF stop
facilitate weight shift to involve limb if DF stop
effects of AFO on people with DF paresis
improve energy efficiency
improve exercise tolerance
improve DF during swing
circular/elestic = more comfy than dorsal AFO
circular/elastic increase walking speed more than dorsal
benefits of FES for post stroke pt
improve DF
improve balance
improved functional mobility
increase gait speed when combined with PT
describe importance of prescribing proper AFO
providing an AFO too early or with too much support could impede neuroplasticity/recovery
if ankle is fully supported, normal muscleactivation may not occur = learned nonuse
insurance only reimburses for AFO every 2 years
