TTA and foot components

Question 1

what does osteomyoplastic TTA allow?

Answer 1

WB on distal end

Question 2

Name the 5 places that are pressure tolerant

Answer 2

Patella Tendon
Gastroc/soleus muscle belly
Pretibial muscles/DF muscle belly
Popliteal Fossa
Shaft of the Fibula

Question 3

Name the 7 places that are pressure sensitive

Answer 3

Tibial Crest and Tubercle
Fibular head and distal end
Patella 
Hamstring tendons
Peroneal n.

Question 4

What would a total surface bearing socket look like

Answer 4

un-rectified socket w/o contours.

You always need to wear these with a liner cause obviously our legs aren’t shaped like this.

Question 5

Pros of total surface bearing sockets

Answer 5

Decrease pistoning

Lower peak pressure in socket

Decrease need for other suspension

Increase ROM at the knee joint due to low walls

Question 6

Cons of total surface bearing sockets

Answer 6

Complicated to don

Perspiration in the system

Anticipate volume changes at initial prosthetic limb and this does not accomidate for that, therefore not appropriate for initial prosthetic limb.

Question 7

Bent knee prosthetic is designed for who

Answer 7

TTA with flexion contracture >50 degrees

Question 8

Symes socket will have what unique feature

Answer 8

window so the malleoli can get in the socket and then the window can be closed for ease of donning

Question 9

Explain where the anterior wall of the socket should be

Answer 9

bisect the patella, 1.5 inches from the PTB, should be bearing weight onto their patella.

Question 10

Explain where the posterior wall of the socket should be?

Answer 10

In line or slightly higher than the PTB when viewed from the back

Question 11

What happens when the posterior wall is too low?

Answer 11

not enough pressure on the patella bar, you’ll slip off or weight bear too much on the distal end

Question 12

Medial aspect of the posterior wall is wider and lower due to what?

Answer 12

two hamstring tendons

You also have a popliteal push (this is a safe wt. bearing area) to direct body wt. onto PTB

Question 13

Where do the medial lateral trim lines generally go for these sockets?

Answer 13

femoral condyles: resist rotations and give stability in this plane. They’re slightly higher than the anterior wall to do this.

Question 14

Bench alignment starting point should be where?

is this before or after walking?

Answer 14

90 degrees with respect to the ground

BEFORE walking

Question 15

What should the alignment of the prosthetic always be looked at with?

Answer 15

shoe on the prosthetic foot!

Question 16

Ankle should be in what position in the sagittal plane on a prosthetic

Answer 16

neutral postition (make sure a shoe is on)

Question 17

What degree of motion should the socket be in the sagittal plane

Answer 17

5-10 degrees of flexion (which would be putting the quad in a mechanically advantageous position on stretch; flexing the knee a little bit)

This also allows a larger surface area for wt. bearing

Question 18

Wt. line should be ____ to the ankle attachment and GRF

Answer 18

anterior. This is how our body naturally works. makes it easier to push off but not too far forward.

Question 19

Alignment of the socket in the frontal plane.

Foot should be ____ to the _____ from the ______. This creates a ______ force

Answer 19

foot should be MEDIAL to the MIDPOINT of the SOCKET.

This creates a varus force at the knee during gait.

Question 20

Knee flexion contractures must be what in the socket?

Answer 20

accommodated!

Question 21

According to Chris (so who knows) what is the most critical part of the prosthesis?

Answer 21

the suspension. Because poor suspension leads to pistoning.

Question 22

Three evils of prosthetics

Answer 22

bacteria
peak pressure
shear forces

All are equally problematic

Question 23

What is the goal of suspension?

Answer 23

to control shear forces within the socket

Question 24

What are the three kinds of anatomical suspension?

Answer 24

shape of the socket, belt straps, thigh corset

Question 25

thigh corset _____ and _____

Answer 25

unloads 30-40% and SUSPENDS This is good for someone with a really short residual limb, unstable knee or fragile skin

Question 26

What are the three major categories of suspensions?

Answer 26

anatomic, suction, vacuume suspension

Question 27

4 major steps to don 3S?

Answer 27

fully deflect the liner Distal end cups the distal limb (make sure there are no air pockets) Roll the liner up the leg Make sure the pin is straight to properly engage the shuttle mechanism

Question 28

4 major steps to don suction liner

Answer 28

fully deflect liner Distal end on distal end Roll up the liner instead of pin (like 3S pt will step down into the socket to force the air up and then roll u the outer sleeve to complete the seal

Question 29

how do you discuss sock management

Answer 29

ply NOT the number of socks

Question 30

If the top wall of the socket is on the distal end of the patella do you have too little or too few ply on?

Answer 30

too few. its slipping too high Could also see pain in distal tibia when WB, abnormal thrusting or pistoning during swing

Question 31

if the top wall of the socket is on the shin bone do you have too little or too much ply

Answer 31

too much ply Could also see no distal end contact

Question 32

What are other ways (other than where the anterior wall of the socket is) to tell if the ply is correct

Answer 32

iliac crests patient report of where the most pressure is, the most should be at the patella tendon

Question 33

What is the largest risk factor related to skin care

Answer 33

change in residual volume: shear or compressive forces

Question 34

What is the biggest thing to not tell someone about sock managment

Answer 34

it has nothing to do with feet being cold

Question 35

Gel liners 2 pros 1 con

Answer 35

decrease peak pressures, and friction reduction Increased infections

Question 36

Generally do you want the limb moist or dry

Answer 36

dryyyyyyy

Question 37

daily care for liners weekly?

Answer 37

mild soap and water, rinse and dry well weekly alcohol

Question 38

Warranty on liners?

Answer 38

25 month/pair

Question 39

If you have two liners how to do wear them?

Answer 39

alternate every other day to increase the life of the liner

Question 40

pylon connects what to what

Answer 40

socket to foot

Question 41

what is the keel

Answer 41

central portion/main structure of prosthetic foot

Question 42

Limited ambulators would use what kind of prosthetic foot?

Answer 42

SACH: solid ankle cushioned heel These have no jt. movement, just the pin going into it. increase in energy to use posterior bumper designed to take body weight and provide shock absorption but does this minimally

Question 43

Single axis allows what motion? How much

Answer 43

PF 15 degrees (generally we need 20) DF 5-7 (generally we need 10)

Question 44

Posterior bumper in single axis controls what motion?

Answer 44

PF

Question 45

Anterior bumper in single axis controls what motion/

Answer 45

DF

Question 46

Why is single axis more commonly seen in TFA.

Answer 46

TTA have quads to be able to control knee during loading and create a bit of shock absorption.

Question 47

Multiaxial allows what motion?

Answer 47

DF and PF Inversion and Eversion

Question 48

What is multiaxial good for that the ones prior to it are not?

Answer 48

uneven terrain: good for higher ambulator someone who wants to walk outside etc.

Question 49

What is the function of the elastic Keel? Who is it good for?

Answer 49

smooth rollover therefore it is easier to ambulate. Good for elderly, light, non aggressive ambulators There is limited push off. bc they can never get into DF

Question 50

Function of dynamic response. dynamic response are energy _____

Answer 50

active push off: as you load the foot it provides some push back Dynamic response is ENERGY STORING

Question 51

Who is the dynamic response good for?

Answer 51

a very active individual

Question 52

Microprocessor feet do what to the terrain you're walking on

Answer 52

actively adjust to it But they're heavy, need maintenance

Question 53

What are hybrid limbs good for?

Answer 53

excellent performance on multip surfaces But they're heavy so not great for runners

Question 54

Energy return of SACH?

Answer 54

39% the best are the dynamic responses and those only go up to 89%. Our human foot gives an energy return of 246%

Question 55

How does the bionic foot function?

Answer 55

two motors and springs Allows for smooth inclines and declines, user is able to change speeds quickly

Question 56

Define "K"

Answer 56

medicare classification of patients POTENTIAL function

Question 57

Define K0

Answer 57

no potential for transfers or ambulation

Question 58

Define K1

Answer 58

potential household ambulator, including transfers

Question 59

Define K2

Answer 59

potential limited community ambulator. Think of a grandparent

Question 60

Define K3

Answer 60

Community ambulator that can VARY THEIR CADENCE.This is like every single one of us jogging or being active etc

Question 61

Define K4

Answer 61

EXCEEDS normal ambulation skills, this is sport specific (flipper, olymp[ic runner etc, insurance s not covering this)

Question 62

who pays for components?

Answer 62

CMS: centers for medicare and medicaid services

Question 63

What did CMS fail to do?

Answer 63

implement standardized and objective process to determine potential functional level (K) but the defined the K levels

Question 64

Name what kind of prosthetic would be used for which K ``` K0 K1 K2 K3 K4 ```

Answer 64

``` K0 = none K1 = SACH K2: flexible keel (easy to anterior shift for low energy cost) and multi axis K3: energy storing feet K4: all feet/specialized level ```

Question 65

what is the 3 point scoring for the Amp Pro and Amp NoPro? Strong correlation with what?

Answer 65

0: inability to perform 1: minimal level of achievement or assistance 2: task completed independently Strong correlation with 6MWT

Question 66

AMPPRO scores are higher or lower than AMP noPRO scores for the same K levl?

Answer 66

Higher, they have an advantage bc they're using prosthetic.

Question 67

inverted pendulum model is important for what?

Answer 67

preservation of the intact limb