Week 3 - Orthotics Lecture Flashcards
Name 7 possible causes of harm of orthotic devices.
- injury to skin or nerve due to pressure points.
- burn as molding over heated material
- failure to protect healing structures.
- undue stress to tendons, joints, etc. due to poor design or positioning.
- inflammation or injury to shortened soft tissue by excessive force (when trying to reduce contracture).
- disuse atrophy
- edema
field of practice
orthotics
device applied to the body
orthosis
- low temperature thermoplastics
- made for specific patient.
custom fabricated orthotic devices
Name 3 goals/objectives of orthotic intervention.
- protective
- corrective
- assistive
Name 4 aspects/goals of protective orthotic intervention.
- Immobile to protect healing structure - prevent any motion, optimal joint alignment
- weak muscles
- prevent joint contractures
- prevent soft tissue contractures
Name 2 aspects/goals of corrective orthotic intervention.
- to encourage proper alignment (correct subluxation of joint)
- to correct deformity
Name 1 aspect/goal of assistive orthotic intervention.
- assists muscles that are weak (ex: tenodesis orthosis)
- no moveable parts
- hold joint(s) in one position
- may be worn intermittently
- can be part of exercise program
static splints
- has moveable parts such as rubber bands, hinges, outriggers
- encourages early motion
- prevents
- corrects deformity
dynamic splints
- combination of static and dynamic splints
- correct deformity
- increase ROM
static progressive splints
low load over time to change soft tissue structures. changes frequently
serial casting
- provides a prolong sustained stretch
- a fast, relatively inexpensive method of correcting burn scar contractures
- flexion contractures of over 30 degrees respond well to casting
- provides circumferential evenly distributed pressure
- offers a successful alternative to dynamic splinting when pt. compliance is an issue ex: pediatrics
serial casting
Most UE splints affect joint ___.
ROM
Articular 3 point pressure splints influence joint ROM by what 4 things?
- immobilization
- mobilization
- restriction
- torque
- circumferential - multiple opposing 2 point pressures, non-articular- do not influence joint ROM
- provide specialized materials to healing structures
coaptation splints
Rigid, hard splint material may cause damage to skin or underlying soft tissue as result of ____ ____.
excessive pressure
Name 3 clinical applications to prevent damage to skin or underlying soft tissue.
- longer, wider splints
- rolled edges on distal and proximal edges.
- continuous, uniform pressure over bony areas not cut outs.
___ ____ on hand splints may provide close fitting support surface for hand.
elastomer linings
heavy felt or foam rubber may help reduce pressure in areas where forces are great or splint is ____.
narrow
The lining/padding should line what?
the patient not the splint
Describe how to increase area of force application on an orthosis.
- pt. can tolerate force/pressure more when it is spread out on a larger surface.
- make splint longer and wider.
How long and wide should splints be for limbs?
1/2 width and 2/3 length of limb.
Splints are lever systems that work in ____.
equilibrium
What is the axis of a wrist splint?
wrist joint
what is the weight/resistance of a wrist splint?
hand
what is the counter force of a wrist splint?
forearm
rotational element of force
production of joint rotation
translational element of force
production of joint distraction or compression
How is force/pull applied to an orthosis?
applied by OT via rubber band, elastic, spring, etc.
When we apply a force, it must be what kind of force?
Rotational force (for joint movement)
Where should force be applied?
must be applied perpendicular to bone we want to move. has to be applied at 90 degrees. as pt. gets better, must change pull angle to get to 90 degrees.
product of force times the length of the arm on which it moves (T = F x d)
torque
what does the amount of torque (effectiveness of force) depend on?
distance btwn joint axis and point of application of the force
As the ____ btwn the joint axis and point of attachment of the mobilization assist increases, the amount of torque on the joint ____.
distance, increases
What is the formula for torque?
T = F x d
How should a secondary joint be addressed with regards to the control reaction effect?
reaction effect controlled by careful support of secondary joint splint fabrication or strap placement.
Describe “3 point fixation” (the 3 parallel force systems in equilibrium as in first class lever system).
the combined downward weights (forearm and hand) must be opposed by equal upward force at the axis (wrist).
Why would you need to widen straps regarding 3 point fixation?
to increase area of force application
straps ___ forces
oppose
foundation from which force is applied or guided
outriggers
How should an outrigger be placed?
must be placed to allow for 90 degree angle of pull
- when mobilizing stiff joints; allows for easier adjustment
- provides greater joint stability
high-profile outrigger
-when joints are flexible/supple and purpose is to substitute for absent motion
low-profile outrigger
articulated splint components = ___ ___
mechanical joints
Articulated splint components must be lined up with what?
anatomical joints
What can happen if splint components are not aligned properly with anatomical joints?
splint may tend to “piston” and create shear or friction forces.
What is a way to increase material strength?
providing contour
Describe 2 clinical applications of contouring splint material to increase material strength.
- round edges
- contour to body part
slightly bent edges
bevel edges
disperse forces
round edges
Friction may lead to what 3 things?
- skin irritation
- blistering
- eventual breakdown
Friction usually indicates what 3 things?
- poor fit
- improper joint alignment
- ineffective fastenings
The radial side of the hand is usually used for which general type of function?
fine motor
The ulnar side of the hand is usually used for which general type of function?
power grasp
Name the 9 creases of the hand.
- thumb - thenar, proximal, distal
- fingers - proximal, middle, distal
- palm - DPC, PPC
- wrist
- follows distal carpal row
- allows wrist motion
proximal transverse arch
- follows line of middle finger
- allows flex/ext of fingers
longitudinal arch
dual obliquity
consider the arches of hand when making splints to preserve function.
Why should sensory considerations be kept in mind by OT when making splints?
must be able to check skin to see if it’s ok
Describe the safe position of the hand.
wrist: 20-30 degrees of extension
MCPs: 40-60 degrees of flexion
fingers - full extension
thumb: abduction/extension
Name 5 aspects of orthoses to educate the pt. about.
- purpose of orthosis, consequences of non-use
- correct application and removal
- wearing schedule
- care: cleaning, heat
- indication of poor fit (pressure points)
no moving parts, to immobilize body part
static orthotic
push or pull force, to mobilize
dynamic orthotic
action of influence that either arrests, produces, or changes the direction of motion.
force
push or pull (kind of force)
nature of force
amount/quantity of influence present
magnitude of force
path or direction along which force acts
line/angle of application
location on structure at which line of force act
point of application of force
increase ___ of ___ application, applies to any type of splint.
area, force
apply passive pulling force in one direction while permitting active resistive motion in the other direction.
dynamic orthoses
force should be applied so that the angle of application is how many degrees to the lever?
90 degrees
which happens if the angle of application is not at 90 degrees?
beneficial effect is lessened and could be potentially dangerous
applies force to a joint to improve PROM, no joint motion permitted while wearing orthotic device.
static progressive orthoses
use ___ ___ ___ for dynamic and static progressive orthoses.
optimum rotational force
production of joint rotation
rotational element
production of joint distraction or compression
translational element
product of force times the length of the arm on which it moves (T = F x d)
torque
the amount of torque depends on what?
distance between joint axis and point of application of the force
if there is a hard end feel of tissue, which types of splints will be indicated?
serial static or static progressive splints
designed to correct contractures by applying a gentle prolonged stretch
static progressive splints
non-elastic component attached to a themoplastic base is adjusted by small increments as the contracture is reduced
static progressive splints
