Fitting and Device Selection Flashcards
OIOIOIOI
OIOIOIOI
What are some pressure sensitive areas of the TT stump?
- Patella
- Lateral tibial condyle
- Tibial tuberosity
- Anterior-distal end of tibia
- Fibular head
- Distal end of fibula
- Distal end of stump with surgical suture
- Medial femoral condyle
- Lateral femoral condyle
What are some pressure tolerant areas of the TT stump?
- Supracondular areas
- Suprapatellar area
- Patellar tendon
- Medial flare of tibia
- Lateral flare of tibia
- Lateral flare of fibula
- Posterior area of the stump
- Popliteal area
- Distal end of stump for total contact socket
A prosthetic set up in too much dorsiflexion can create what?
Encourages knee flexion at heel strike, causing patient residual limb hits the anterior aspect of the socket, causing skin breakdown.
What is one of the biggest concerns when first fitting a patient for a prosthetic?
In-bearing = Most patients have neuropathy, leading to the patients not being able to feel the residual limb as well, leading to skin breakdown.
SOCKS
SOCKS
What happens when the prosthetic is ill fitting due to volume loss or atrophy of the residual limb?
Patella sinks into socket causing fib-head pressure, condyle pressure, and tibia pressure.
First 0-__m after below knee amputation, patients are more likely to have volumetric, cylindrical, circumferential changes as well as atrophy. What fixes this?
- 18 months
- Adequate amount of socks to lift residual limb out of prosthesis.
________ liner provides high stability and good adhesion if your limb has a lot of soft-tissue. It performs best with shuttle-lock suspension, what is this?
- Silicone
- “Shuttle lock suspension” means there is a pin attached to the end of the liner which inserts into a locking mechanism in the bottom of the socket. The lock connects your socket to your prosthesis.)
____________ has a unique ability to flow away from high pressure. That means the pressure in your socket is well distributed.
Polyurethane
__________ is soft, cushiony and highly elastic, offering good protection for low activity for many types of residual limbs. Usually a thermoplastic elastomer, which contains skin-friendly white oil, it is especially good for residual limbs with dry skin.
Copolymer
- Silicone liners are for individuals with a _______ to _______ activity level.
- Polyurethane is for individuals from ______ to especially _______ activity levels.
- Copolymer liners are for individuals with a ______ activity level.
- low to moderate
- low to especially high
- low
SUSPENSION METHODS
SUSPENSION METHODS
What are the 4 main suspension methods?
- Pin locking
- Lanyard
- Suction
- Elevated vacuum
What is pin-locking suspension?
A silicon or gel liner with a pin at the bottom of the liner is used on the residual limb. When the limb is placed into the socket the pin has to go into a locking mechanism at the bottom of the socket. This mechanism will lock the pin in place, creating a secure suspension in the socket.
What are the advantages of pin-locking suspension?
- Auditory feedback for the user when pin engages
- Easy donning and doffing
- Can be done in sitting position
- Forgiving with volume fluctuations
What are the disadvantages of pin-locking suspension?
- Elongation effect can occur at bottom of the residuum and cause skin breakdown
- Wear and tear on liners
- When the pin is misaligned or the liner is donned incorrectly the locking mechanism will not be engaged
What are some indications for pin-locking suspension?
- Volume fluctuation
- Secure mechanical suspension
- Mid-length to short amputations
- Absorb sheer forces
What are the indications for lanyard suspension?
- Geriatric patients can donn while sitting
- Obese patients
- Poor dexterity/eye sight
- Liner alignment is not critical
- Bulbous limbs
What is suction suspension?
A liner that is donned on the residuum is used to create suction instead of the skin suction described above. These liners are usually made of silicone or gel, to create a seal with the inside of the socket the liner can have silicone rings/ribs or a membrane.
What are the indications for suction suspension?
- Stable limb volume
- Long residual limb allows for more room for components
- Difficulty engaging pin-locking liner
What are the advantages of suction suspension?
- Even pressure throughout socket
- Secure fit
- Donning in a sitting position is possible
- Stabilize excess residual tissue
- Good suspension even with small volume fluctuations
What are the disadvantages of suction suspension?
- Relatively expensive
- Wear and tear on liners
- Poor suspension with significant volume fluctuations
- Hand strength and dexterity needed
- Lubricant needed
What is elevated vacuum suspension?
Suction suspension is created with direct contact between the liner (or with the membranes on the liner) and the socket wall. With this system a mechanism/pump sucks the air out between the liner and the socket creating a negative pressure that is the same across the entire surface. To seal off the system an external sleeve or seal is used at the top of the socket.
What are the indications for elevated vacuum suspension?
- Offers rotation and shock absorption
- Reduces shear forces/pistoning within socket
- Improved proprioception
What are the advantages of elevated vacuum suspension?
- Creates a constant negative pressure and allows for better suspension when there is volume fluctuation
- Less pistoning and rotation occur within the socket
What are the disadvantages of elevated vacuum suspension?
- More expensive
- Mechanical components that can break
- Adds weight to the prosthesis
Many patients have to wear an ________ sleeve over the vacuum suspension to help.
external
FOOT SELECTION
FOOT SELECTION
What are 7 foot selections in regards to prosthetics?
- SACH
- Single Axis
- Multi-Axial
- Dynamic Response
- Multi-axial w/ Dynamic Response
- Hydraulics
- Microprocessor
What are multi-axial feet for?
- Someone who isn’t super high activity, but does want to be a community ambulator.
- Helps to acclimate to uneven terrain.
What are sports feet used for?
- People involved in athletics
- Also commonly used in pediatrics
What is dynamic response feet?
-Straight ahead energy, not getting multi-axial component.
What are heel height adjustable shoes used for?
-Allows for needs of different shoes.
What is the main use of shock technology in prosthetics?
Decreases abuse on residual limb
What is the use of a hydraulic ankle?
Allows the ability to control plantar and dorsiflexion at heel strike and midstance.
