Lower Limb

Question 1

How much socket adduction is needed in Transtibial Bench alignment?

Answer 1

5 degrees socket adduction (lateral tilt)

Question 2

How much socket flexion is needed in TT bench alignment?

Answer 2

5 degrees socket flexion (anterior tilt)

Question 3

How do you find the lateral reference line on a TT socket?

Answer 3

Drop a plumb bob at the mid patellar tendon level..this should pass 1 1/4”ahead of the center line of the pylon attachment C-clamp (substantially taller and heavier than average 1 1/2” ahead.

Question 4

How do you find the posterior reference line on a TT socket?

Answer 4

drop a plumb bob at the socket brim that passes 1/2” lateral to the centerline of the pylon attachment clamp. 1/4” for shorter patients

Question 5

How to determine the appropriate height of the a trans tibial Prosthesis?

Answer 5

Establish the distance from MTP to the heel of the prosthesis and pick the appropriate pylon.

Question 6

Attach the foot and shoe so that the medial border of the shoe is ________________________

Answer 6

Parallel to the line of progression.

Question 7

The foot is inset to a ____

Answer 7

1/2”

Question 8

The lateral reference line should fall ____ anterior to the ankle bolt

Answer 8

1 1/4”

Question 9

Where does the TKA line fall in reference to the hip, knee and ankle/foot?

Answer 9

• Posterior to hip
• Anterior to knee
• Anterior to foot

Question 10

A patient has lateral and distal redness what might be the cause?

Answer 10

Socket is too large

Question 11

A patient has proximal lateral and distal medial redness what might be the cause?

Answer 11

-Adducted socket

Socket M/L too large

Question 12

Patient is bottoming out secondary to: decreased residual limb volume what’s the reason?

Answer 12

Patient not donning appropriate amount of socks or the socket was made initially too big.

Question 13

Patient is bottoming out secondary to: Lack of distal end contact causing what?

Answer 13

Verrucous hyperplasia (caused by greater proximal pressure than distal pressure)

Question 14

Patient presents with fibular head redness what is the cause?

Answer 14

• Patient is bottoming out in the socket
• socket is too large
• Adequate relief not made for the fib head

Question 15

patient presents with anterior proximal and posterior distal redness?

Answer 15

Insufficient initial socket flexion
Shoe change with decrease heel height?
Heel lever too short, or heel bumper/cushion too soft

Question 16

What causes anterior distal pressure?

Answer 16

• A/P too big
• Posterior brim too low
• Insufficient relief
• Excessive use of knee extension
• Heel lever too long
• Excessive initial socket flexion

Question 17

what must you do regarding the skin during the casting section of the exam?

Answer 17

Inspect the residual limb for any irritation and point these areas to the examiner. make sure the examiner realizes that you were not the reason of these irritations ,wounds

Question 18

What must you do to protect the residuum or liner during casting?

Answer 18

Roll on two layers of cotton stockinette over the residual limb or apply a thin layer of plastic wrap around the residuum to prevent indelible from showing on the skin and to facilitate ease of removal of cast.

Question 19

How to avoid unwanted motion of the stockinette during casting?

Answer 19

Apply elastic webbing around the patient’s waist. then crossing anteriorly (in an “X” pattern) and attach to medial and lateral border of stockinette using two yates clamps.

Question 20

what position should you put the TT patient in to cast?

Answer 20

instruct the patient to maintain approximately 20 degrees of knee flexion. This is done so that bony prominences, patella tendon, and hamstrings are easily identified. ensure patient is relaxed

Question 21

What measurements should you take for TT socket casting?

Answer 21

Knee ML, PML, AP, limb length, circumferences, shoe/foot size, and knee center to floor length of the contralateral leg

Question 22

what landmarks should be delineate and mark with an indelible?

Answer 22

Patella, Patella tendon, Tibial crest, Tibial tubercle, Anterior distal end of tibia, medial/lateral border of tibia , medial tibial flare, medial epicondyle, head and neck of the fibula

Question 23

How should the residual limb be wrapped while casting?

Answer 23

Either using a figure-of-8 or circumferential wrapping method. be sure to use even pressure throughout the entire casting process to prevent roping.

Question 24

Where should you fingers be placed during casting?

Answer 24

Place thumb tips on both sides of the patellar tendon, while simultaneously using your third through fifth fingers to exert pressure onto the popliteal area. index fingers being used to prevent plaster cast swelling medially and laterally.

Question 25

How to establish alignment for the cast?

Answer 25

Draw coronal and sagital vertical alignment lines on the outside of the cast as it is finishing hardening.

Question 26

Whats the first step to take before applying plaster for a PTB-SC socket type casting?

Answer 26

Measure the distance from the distal third of the medial femoral condyle to the distal third of the lateral. measurement should be the length of the plaster panel

Question 27

How Long should the PTB-SC panel be?

Answer 27

The panel should be approximately 4-6 layers thick.

Question 28

Where is the placement of the thigh and corset joints:

Answer 28

average starting location for joint centers is 2 1/4” superior to the patellar tendon protuberance and slightly posterior to the sagittal midline

Question 29

True or false

Joints must be square to each other and the same height from the floor?

Answer 29

True

Question 30

Why are the thigh and corset joints tilted anteriorly?

Answer 30

So that they will not reach maximum extension until the patients knee is fully extended.

Question 31

The extension stop in the joint and corset suspension is provided by a __________

Answer 31

Check strap

Question 32

What does the check strap do?

Answer 32

The check strap can be adjusted to limit extension of the patient’s knee, and will prevent the joints from reaching their “stops” so they not wear out as quickly?

Question 33

What is the resulting pressure of a knee center placed to distally?

Answer 33

Pressure will be felt on the anterior distal thigh and posterior proximal thigh.

Question 34

What is the resulting pressure of knee center placed to proximally?

Answer 34

Pressure will be felt at the posterior distal thigh.

Question 35

What are possible causes of a trans tibial prosthesis appearing higher than the sound limb when sitting.

Answer 35

• Posterior brim of the socket is too high
• Insufficient hamstring relief
• Incorrect length

Question 36

What are causes of rapid knee flexion?

Answer 36

• Prosthetic socket is placed (slid) to far anterior
• Heel lever excessively long
• Patient is wearing new shoes with an increase in heel height
• Excessive stiff heel action

Question 37

What are possible causes of distal limb edema or discoloration:

Answer 37

Lack of total contact

short prosthetic socket

Question 38

What deviations should be expected when converting previous joint and corset users to a PTB Type socket?

Answer 38

• Excessive knee extension
• Medial lateral instability
• Patient insecurities