L6 Orthotics Flashcards
purpose of orthotics
control abnx movement compensations by bringing foot to the floor
biomechanical balanced kinetic chain
maintain subtalar neutral position
Why does the alignment of the foot matter?
foot position affects GRF, mechanical chain changes when the foot is in a different position and GRF are different
function of the subtalar joint in initial contact
shock absorber
pronation, rotation of the tibia to absorb?
function of the subtalar joint in midstance`
loading response moves joint to pronation
over pronation can rotate tibia and affect the knee
function of the subtalar joint in terminal stance
joint supinates to become rigid for toe off
What issues can be created by over pronation in closed chain
anterior pelvic tilt
IR of femur
valgus knee
med rotation tibia/fibula
medial rotation talus
adduction/PF talus
what issues can be created by over supination in closed chain?
posterior pelvic tilt
femur ER
knee varus
lat rotation tibia/fibula
abduction/DF talus
how to measure varus and valgus
varus: ankles together, measure distance between knees
valgus: knees together, measure distance between ankles
knee adduction moment (KAM)
during walking, GRF goes up and medial towards midline
places knee into varus
compresses medial knee
contributes to knee OA
this force is increased if the knee is in valgus
types of shoe orthotics
heel cup
heel lift
wedge
stability//control, soft tissue protection
principles required for orthotics
easy for patient
soft tissue
at risk patient
tolerate compression and shear
consider functional level of patient
shoe inserts function
modifies heel/midfoot/forefoot
padding for pain
heel lift for leg length
wedge for supination/pronation
correct pronation to reduce medial OA with what orthotic?
valgus wedge orthotic insole
navicular drop test
over pronation test
measure midfoot collapse
measure navicular in seated on paper, stand and measure distance it drops
positive > 10mm
considerations to assess the need of ankle orthotic
- gait deviation: swing/stance
- protect from injury like pressure/joint instability
AFO prescription for what conditions?
weakness
stroke
CP
head injury
peripheral neuropathy
alignment
spinal cord injury
progressive diseases
ankle foot orthotic
leaf spring AFO
gives energy to patient’s foot to bring it back into dorsiflexion
used for foot drop
support weight of foot in swing phase to clear floor
causes of foot drop
peripheral neuropathy
Fx knee or fibular head
knee dislocation
cross ing legs
losing weight - they can cross legs now and stress nerve
bed rest
MS
stroke/cva
myositis
solid afo
used in neuro pts with lots of spasticity for more control of tibia, support calcaneus
reduce PF
static/rigid AFO
holds foot in biomechanical neutral
disadvantages of solid AFO
interferes with transitions of all ankle rockers due to fixed ankle position
prevents controlled lowering of foot
