orthotic Flashcards
Orthotic
- Externally applied device used to modify the structural or functional characteristics of the neuro-musculo-skeletal system
- Modifies external forces or moments acting across one or more joints
- Compensates for inadequacy of the individual
- AFO - ankle foot orthosis
Purpose of orthosis
- Modify joint motion
- Prevent:
– “Giving way”
–Resist spasticity
Bracing
Brace is designed to use a torque to push into knee valgus position. Don’t want load on medial condyles. Osteoarthritis tends to be put in knee varus and adduction loads the medial condyles and reduces spacing. Painful.
Lateral Wedging the foot
Varus moment is less with lateral wedge. Less painful for people with OA.
Medial Flare on Foot
Building this up helps in preventing eversion/pronation through the foot. Increases the external varus moment
When do wounds occur?
Greater than 30 mm Hg; Greater than capillary closing pressure.
Diabetes Mellitus: Higher pressure over shorter periods (Feet)
____ may put someone more at risk of developing a pressure ulcer
Lower BMI
When walking and pushing off why are there higher pressures later?
The pressure is located over smaller bony structures located in the foot. Puts DM patients highly at risk for skin damage.
Extrinsic factors affecting tissues
Shear (ALMOST IMPOSSIBLE TO MEASURE)
* Movement parallel to support surface
* Poor fit of device, altering the angle of the support surface
* Pressure with increased shear may disrupt blood flow further
* Uneven surface increases shear.
Interface microenvironment
* High moisture environment
* Incontinence or sweat? Leads to change in skin properties.
* Risk of fungus; Need breathable materials, need temperature - cooler
Intrinsic factors affecting tissue
Tissue viability: Can be influenced by circulation, sensation and nutrition.
Diabetic Foot Ulceration
Common areas of high pressure
* lateral border of 5th metarsal
* bottom of 1st metatarsal head
Debride calluses as it increases temperature
Explain how this helps prevent pressure ulcers
Want axis in front of the area that is where the pressure is highest. By having axis reducing pressure in area and rolling off the foot so time is reduced as well.
