254 Edm: Prosthetics

Front 1

what is an ankle disarticulation?

Back 1

Syme's amputation

-attachment of heel pad to distal end of tibia for WBing

Front 2

Levels/lengths of transfemoral amputations?

Back 2

1. Long above-knee amputation (AKA), >60% of femur spared
2. Ideally an AKA: 35%--60% of the femoral length spared
3. Short AKA < 35% of the femoral length spared

Front 3

levels/lengths of transtibial?

Back 3

1. long below-knee amputation (BKA): > 50% of tibial length is spared
2. standard BKA, 20%-50% of the tibial length is spared
3. short BKA, less than 20% of the tibia is spared

Front 4

Knee disarticulation amputation:

Back 4

Amputation through the knee joint with the femur intact

Front 5

Hip disarticulation amputation:

Back 5

Amputation through the hip joint
Pelvis intact

Front 6

Hemipelvectomy amputation:

Back 6

Resection of the lower half of the pelvis

Front 7

Hemicorporectomy amputation:

Back 7

amputation of both lower limbs and the pelvis below the L4-L5 level

Front 8

Transradial amputation:

Back 8

below-elbow amputation

Front 9

Transhumeral amputation:

Back 9

above-elbow amputation

Front 10

what is the maximum ply of socks?

Back 10

should not exceed 15-ply thickness for proper fit and weightbearing of the socket

Front 11

Terminal device does what?

Back 11

Lower-limb prosthesis: TD is a foot
Upper-limb prosthesis: TD is a hook or hand

Front 12

Solid ankle cushion heel (SACH) foot is what?

Back 12

1. The most commonly prescribed foot
2. Non­ articulated
3. Contains an energy-absorbing cushion heel & internal wooden keel

4. limits sagittal plane motion while permitting PF in early stance

5. allows rollover at terminal stance
6. Permits a very small amount of mediolateral (frontal plane) and transverse plane motion

Front 13

SACH foot assists in what?

Back 13

Hyperextension of knee (knee stability) during stance

Front 14

Disadvantages of non-articulating feet (SACH foot)?

Back 14

1. Not used over uneven terrain for long-distance ambulation

2. if energy conservation is needed

Front 15

SAFE foot allows for what? and is prescribed for who>

Back 15

1. A version of the solid ankle cushion heel (SACH) foot

2. Walking on moderately uneven terrain because of the greater range of mediolateral motion permitted in the rear-foot

3. prescribed for More active individuals

Front 16

Disadvantages of SAFE foot:

Back 16

1. Heavier
2. More expensive
3. Less durable than SACH foot

Front 17

Seattle foot is what?

Back 17

1. Slightly flexible plastic keel bends at heel contact
2. Keel stores energy and recoils in late stance releasing energy for springy termination to stance

Front 18

Disadvantages of Seattle foot:

Back 18

Heavier than SACH foot

Front 19

Flex-Foot (Springlite foot) is what?

Back 19

1. Includes a long band of carbon fiber material, which extends from the toe to the proximal shank & to posterior heel section
2. the long band acts as a Leaf spring, enabling foot to store energy in early & mid-stance & then release it in late stance

Front 20

The flex-foot is used with who?

Back 20

More active individuals
In certain athletic circumstances

Front 21

Disadvantages of Flex-Foot (Springlite foot):

Back 21

More expensive than SACH foot

Front 22

Single axis foot is what?

Back 22

1. most common articulating foot
2. More stable (permits only sagittal plane motion/DF and PF

3. does not permit medioloateral or transverse motion

4. prescribed for bilat TFA

Front 23

Disadvantages of Single-axis foot:

Back 23

Permits PF & DF only
Limited on uneven terrain

Front 24

what are multi-axis foot and disadvantages?

Back 24

1. Has components that move slightly in all planes to aid the patient in walking on uneven terrain and slopes

2. Disadvantages of multi-axis foot:
-Heavier and less durable than single-axis or non-articulated foot

Front 25

Reliefs over pressure sensitive areas in the Patellar-tendon-bearing (PTB) socket are where?

Back 25

1. Anterior tibia
2. Anterior tibial crest
3. Fibular head & neck
4. Peroneal (fibular) nerve

Front 26

Pressure-tolerant areas in Patellar-tendon-bearing (PTB) socket are:

Back 26

Patellar tendon
Medial tibial plateau
Tibial & fibular shafts
Distal end of tibia

Front 27

Supracondylar cuff is what?

Back 27

A leather strap that buckles over the femoral condyles & permits the user to adjust the snugness of the suspension easily

Front 28

Supracondylar suspension (SC) is what?

Back 28

1. Medial and lateral walls of the socket extend up and cover the femoral condyles
2. A wedge is placed between the socket and the medial epicondyle

3. Increases mediolateral stability

Front 29

Supracondylar/suprapatellar suspension (SC/SP) is what?

Back 29

Similar to the SC with the addition of an anterior wall, which terminates above the patella
May interfere with kneeling & is very visible when the wearer sits

Front 30

Supracondylar/suprapatellar suspension (SC/SP) is used for what?

Back 30

Short residual limbs

Front 31

Thigh corset suspension is what?

Back 31

Has metal hinges attached distally to the medialand lateral aspects of the socket & proximally to a leather corset that may be as high as the ischial tuberosity

Front 32

Thigh corset suspension provides what?

Back 32

Larger area for weight bearing

Front 33

Thigh corset suspension is prescribed for who?

Back 33

Individuals with sensitive skin and unstable knee joint

Front 34

Disadvantages of Thigh corset suspension:

Back 34

Bulky, heavy, and may allow for pistoning

Front 35

what does a single axis knee unit provide?

Back 35

1. permits kneemotion around a fixed axis

2. knee flexion needed during late stance and swing

3. knee locks in ext for heelstrike and foot flat

Front 36

what is a polycentric (multiple axis) knee unit?

Back 36

allows adjustment to center of knee rotation

-more stable

-less often used bc of complexity

Front 37

Friction mechanism does what?

Back 37

modifies the speed of knee motion, providing resistance to pendulum motion at the knee

Front 38

who is the constant friction mechanism usually prescribed for?

Back 38

Older individuals who do not vary their gait speeds greatly

Front 39

what are variable friction knees?

Back 39

-allows changes in amount of friction during a given swing phase

-e.g. high friction to reduce heel rise in early swing

-decr friction to permit easy swing in midswing

-incr friction to dampen terminal swing impact

Front 40

Hydraulic knee units (fluid controlled)/pneumatic knee units (air controlled) do what?

Back 40

Adjust to the individual's walking speed and vary the resistance accordingly

Front 41

Hydraulic/pneumatic knee units are prescribed for who?

Back 41

Younger, more active individuals

Front 42

Disadvantages of Hydraulic/pneumatic knee units:

Back 42

1. They are heavier
2. More complicated
3. Require increased maintenance
4. Have higher costs than other knee units

Front 43

`Extension aid is what?

Back 43

1. Elastic webbing stretches during knee flexion (early swing) and recoils to extend the knee (late swing)
2. An internal extension aid is an elastic strap or coiled spring within the unit and acts the same

Front 44

Knee stabilization in extension achieved by:

Back 44

1. Prosthetic alignment (TKA line)
2. Manual lock
3. Friction brake
4. Extension aid

Front 45

how does prosthetic alignment allow knee stability?

Back 45

1. Knee center is aligned posterior to the TKA line
2. Knee aligned farther posterior will be very stable (will not flex easily)
May be prescribed for short residual limbs

Front 46

Manual lock is what?

Back 46

-pin that limits knee flexion and is released by an unlocking lever

-Prescribed for individuals who require a constantly locked knee; e.g., weakness of hip extensors
-Difficulty with clearance of the leg during swing can be controlled by shortening the total prosthetic limb length "'1 cm (-0.4 in)

Front 47

Friction brake is what?

Back 47

A device that increases friction at midstance to prevent knee flexion, but permits smooth knee motion through the rest of the gait cycle

Front 48

what ar pressure tolerant areas for the AKA socket?

Back 48

1. ischial tuberosity

2. gluteal muscles

3. lateral side of the thigh,

4. to a lesser extent the distal end of the amputation

Front 49

what are pressure intolerant areas for AKA socket?

Back 49

1. distolateral end of the femur

2. pubic symphysis

3. perineal area

Front 50

Quadrilateral socket is most commonly used for who? and what are the dimensions?

Back 50

AKAs
1. Medial wall is same height as posterior
2. Anterior and lateral walls are 2.5 to 3 inches higher

narrow AP

wide ML

Front 51

what is the design of the quadrilateral socket?

Back 51

horizontal posterior shelf to support
Ischial tuberosity
Gluteals

Front 52

With a Quadrilateral socket reliefs are provided for what?

Back 52

Adductor longus tendon
Hamstring tendons
Sciatic nerve
Gluteus maximus
Rectus femoris

Front 53

Silesian bandage is what?

Back 53

1. strap that anchors the prosthesis by reaching around the pelvis

2. controls for rotation

Front 54

Metal pelvic band adds control for what?

Back 54

type of AKA suspension

1. Rotation
2. Hip ABD/ADD
3. Reduces Trendelenburg gait deviation
4. Adds extra weight

Front 55

Possible causes for Excessive knee flexion during stance with Transtibial amputation:

Back 55

1. Socket may be aligned too far forward or tilted anteriorly
2. Cuff tabs too posterior
3. stiff heel cushion
4. High heel shoes

5. insufficient PF
6. Knee flexion contracture
7. Weak quadriceps

Front 56

Possible causes for Inadequate knee flexion during stance with Transtibial amputation:
Socket may be aligned too far back or tilted posteriorly

Back 56

1. Excessive PF
2. PF bumper or heel cushion too soft
3. Low heel shoes
4. socket too far posterior
5. Weak quadriceps

Front 57

Possible causes for Lateral thrust at midstance with Transtibial amputation:

Back 57

=varus moment at the knee

Foot is inset too much

Front 58

Possible causes for Medial thrust at midstance with Transtibial amputation:

Back 58

=valgus moment at knee

Foot is outset too much

Front 59

Possible causes for Drop off or premature knee flexion in late stance with Transtibial amputation:

Back 59

1. Socket is set too far forward or excessively flexed
2. excess DF of the foot
3. Prosthetic foot keel too short (Toe lever too short)

4. high shoe heel

5. insufficient PF
6. Knee flexion contracture

Front 60

what is heel and toe lever?

Back 60

Heel lever: perpendicular distance from heel cushion to center of socket (effects initial contact)

-too short = knee hyperext

-too long = excessive knee flexion

Toe lever: perpendicular distance from center of socket to end of keel (effects terminal stance)

-created by TKA line
-long toe lever = ext moment at terminal stance

-short toe lever = flexion moment at terminal stance

-

Front 61

Possible causes for Delayed knee flexion during late stance with Transtibial amputation:

Back 61

-Patient feels as though walking "uphill"

1. Socket is set too far back or lacks sufficient flexion
2. DF bumper is too stiff causing excess PF
3. Prosthetic foot keel too long (Toe lever too long)

4. low heel

5. excessive PF

Front 62

Possible causes of medial heel whip in stance phase for AKA?

Back 62

ER of knee bolt

Varus knee alignment

Front 63

Possible causes of lateral heel whip in stance phase for AKA?

Back 63

IR of knee bolt

valgus knee alignment