if goal is immobilization to protect joint must do what?
substitute for the lack of intrisic joint stability normally achieved by bones, muscles, ligaments
what are the 2 things an orthotic prescription must take into account?
control and assist movement
orthotics and application of forces
orthotics have increased pressure at points of force application
greater concern for patients with sensory or cognitive deficits
to abvoid pain and skin breakdown forces should be sustained over as _______large/small a body surface area as possible because it ______incr/decr the force
Large
decreases
what is the 3 point loading system in orthotics?
sum of forces and sum of bending moments = zero
T/F effectiveness of 3 point loading system is strongly influenced by the location of forces relative to the joint axis
T
the _____farther/shorter the end forces are from the joint the ______greater/lesser their moment arms
the ______smaller/larger the magnitudes required to produce a given torque at the joint
farther
greater
smaller
what 4 things make up an ideal orthotic
1. performs desired function
2. improves QOL
3. comfortable during use
4. meets patients needs and goals
T/F orthoses should control only those movements that are considered abnormal while permitting free motion of unimpaired segments
True
foot orthoses enhance function by relieving pain by the following 4 ways:
1. transfer WB to pressure tolerant areas
2. minimize contact with pressure sensitive areas in shoe
3. correct alignment of flexible segment
4. accomodate for a fixed deformity
What is a SMO used for?
seen in peds patients
address sagittal plane problems and facilitate foot clearance in swing
solid AFO is used for?
in patients who need total immobilization of ankle-foot complex to be stable
helps with PF, inversion, eversion, DF control--faciliated knee extension in stance
solid AFO's control for...
foot drop in swing
hyperextension of knee if in slight DF
hyperflexion of knee if in slight PF
PLS dorsi assist AFO used for?
during loading response PLS substitutes for eccentric contraction of pretibials providing controlled lowering of foot
once limb is unweighted for swing PLS holds ankle at 90d for clearance and position
double upright dorsi assist afo used for?
assists DF in swing and smooth initial contact to loading response
bad things: heavier, less cosmetic, inability to change shoes