LE Orthotics --> part 2 (1) Flashcards
what must be addressed for those w/ knee weakness
stance phase and swing phase
stance phase –> knee weakness
quad weakness
quad weakness –> stance phase
knee instability at heel strike
weight acceptance during mid stance
knee instability at heel strike –> stance phase
GRF is posterior to the knee
eccentric contraction of the quads control movement
weight acceptance during midstance –> stance phase
there could be knee bucking at mid-stance
quads stabilize during mid-stance
soleus from below gives some control of knee extension
swing phase –> knee weakness
quad weakness and hamstring weakness
quad weakness –> swing phase
consistent knee flexion (60 degrees)
knee flexion (leg clearance) during swing
eccentric quads control motion
hamstring weakness –> swing phase
consistent knee extension in preparation for HS
why is control of the knee difficult
changes in walking speed
general description of KAFO
thigh shell
knee joint
calf/pre-tibial shell
closure (strap)
w/ or w/o articulated ankle
foot plate
foot and ankle components of KAFO
same as AFO
knee joint axes
single axis
polycentric/multi-axis
single axis –> knee joint
hinge
polycentric/multi-axis –> knee joint
changing axis
hard to align
what do all knee joints give
ML control
knee controls
free knee
offset knee joints
locks
adjustable locks
free knee
free flexion/extension to 0 degrees
used primarily for ML control
offset knee joints
axis is posterior to uprights
what does the position of the offset knee create
an extension moment
the offset knee joint allows
free flexion and extension
free during swing
how is the offset knee joint locked during stance
GRF
why would we use an offset knee joint
quad weakness
locks –> knee control
ring drop lock
swiss lock/ bail lock/ cam lock
adjustable locks
ring drop lock is
manual
to unlock the ring drop lock
lift it
the ring drop lock could be
spring loaded
the ring drop lock has an
retention button
when would we use a ring drop lock
problems w/ spasticity, contractures, and balance
swiss lock/bail lock/cam lock –> unlocking
bail to unlock
lift bar up
how does the swiss lock/cam lock/bail lock lock
automatically w/ extension
the swiss lock/cam lock/bail lock has no
binding
when is it better to use a swiss lock/cam lock/bail lock lock
better w/ spasticity
better w/ contractures
less balance issues
adjustable locks are
range limiting
what do adjustable locks limit
motion/post surgery
when are adjustable locks used
contractures
stance control KAFO
SCKO
locks during stance and unlocks during swing
how is the SCKO activated
weight or gait (position)
activates the locking and unlocking
when does the knee lock –> SCKO
HS weight accepted/knee extended
when will the knee unlocks –> SCKO
end of MS to PO when weight is removed/knee hyperextends
some SCKO use
sensors and computers
indications for a SCKO
weak quads
knee instability
polio or post-polio syndrome
MS
SCI
spinal trauma
unilateral paralysis
contraindications for a SCKO
no hip muscle
poor mental status
spasticity
knee contracture
weight limitation
poor mental status –> contraindications SCKO
difficult to learn to use orthosis
