Lower Extremity Prosthetic Componentry

Question 1

Partial foot/ray resection =
Toe disarticulation =
Partial toe =

Answer 1

resection of 3rd, 4th, or 5th metatarsals or digits
disarticulation at MTP joint
excision of any part of one or more toes

Question 2

Chopart =
Lisfrank =
Transmetatarsal =

Answer 2

transtarsal
disarticulation of midfoot
removal of forefoot through all 5 MTP bones

Question 3

what kind of gait deviation is common after the following minor LE amputations?
– toe:
– great toe:
– Ray:
– MTP or proximal:

Answer 3

– minor gait abnormalities
– loss of push-off
– decreased gait speed, limited LE ROM
– decreased stability, gait speed, and other gait deviations

Question 4

Syme’s amputation/ankle disarticulation:
– preserves:
– removal of:
– complicated prosthetic fit due to:
– (can/cannot) ambulate without prosthesis

Answer 4

– heel pad – attached to distal end of tibia
– malleoli
– limited space
– can

Question 5

what is the ideal length for a transtibial/below the knee amputation?

Answer 5

mid tibia –> allows for prosthetic use
fibula should be 0.5-1 cm shorter than tibia for prosthetic fit

Question 6

transtibial:
– if < 9 cm, consider:
– if < 5 cm, consider:

Answer 6

– removing fibula
– knee disarticulation or TFA

Question 7

where does the knee joint fall compared to intact limb on someone with a knee disarticulation?

Answer 7

tibia shaft - below tibial plateau and fibular head

Question 8

what is hemipelvectomy?
what is it commonly due to?

Answer 8

resection of part of pelvis
commonly due to cancer or trauma

Question 9

what is hip disarticulation?
what remains intact?

Answer 9

amputation through hip joint
pelvis remains intact

Question 10

what are K levels used for?

Answer 10

assess patient’s potential functional ability
determines reimbursement for componentry

Question 11

what is considered a K-level 0?

Answer 11

does not have the ability or potential to ambulate or transfer safely with or without assistance and a prosthesis does not enhance their QOL or mobility
– not eligible for prosthetic

Question 12

what are some mobility characteristics of a K0 patient?

Answer 12

– does not have sufficient cognitive ability to safely use prosthesis
– requires assistance for transfers and prosthesis does not improve mobility or independence
– wheelchair dependent
– bedridden - no need/capacity to ambulate or transfer

Question 13

what is considered a K-level 1?

Answer 13

• ability or potential to use a prosthesis for transfers or ambulation on level surfaces at fixed cadence
• household ambulator

Question 14

what are some mobility characteristics of K1 patient?

Answer 14

• sufficient cognitive ability to safely use prosthesis with or without AD and/or assistance of one person
• safe but limited ambulation at home or on similar flat surface - w/ or w/o AD, w/ or w/o assistance from one person
• requires wheelchair for activities outside the home

Question 15

what is considered a K-level 2?

Answer 15

• ambulation with ability to transverse low level environmental barriers (curbs, stairs, uneven surfaces)
• limited community ambulator

Question 16

a K2 level patient can: (w/ or w/o AD, w/ or w/o assistance of one person)

Answer 16

• perform level 1 tasks
• ambulate on flat, smooth surface
• negotiate a curb
• access public or private transportation
• negotiate 1-2 stairs
• negotiate a ramp built to ADA specifications

Question 17

when do K2 patients utilize a wheelchair?

Answer 17

distances beyond the perimeters of the yard/driveway, apartment building, etc.

Question 18

do K2 patients have the ability to increase cadence?

Answer 18

only able to for short distances or with great effort
– not necessarily changing speeds regularly

Question 19

what is considered a K-level 3?

Answer 19

• variable cadence, typical of community ambulator
• transverse most environmental barriers
• may have vocational, therapeutic, or exercise activity that demands prosthetic utilization beyond simple locomotion

Question 20

A K3 patient can complete Level 2 tasks PLUS: (w/ or w/o AD, NO assistance)

Answer 20

• walk on terrain that varies in texture and level
• negotiate 3-7 consecutive stairs
• walk up/down ramps built to ADA specifications
• open and close doors
• ambulate through crowded area
• cross controlled intersection within community within the time limit provided
• access public or private transportation
• dual ambulation tasks (walk and talk)

Question 21

what is considered a K-level 4?

Answer 21

• prosthetic ambulation that exceeds basic ambulation skills
• exhibits high impact, stress or energy levels (running, jumping, skipping)

Question 22

what kind of person is commonly a K4?

Answer 22

child
active adult
athlete

Question 23

what are K4 activities? (w/ or w/o AD, NO assistance)

Answer 23

running
repetitive stair climbing
climbing of steep hills
being a caregiver for another individual
home maintenance

Question 24

Match the following foot/ankle component with the appropriate K level:
– flexible-keel feet, multi-axial feet
– any, includes microprocessor
– external keel, SACH or single axis
– flex foot, energy storing foot, multi-axial, or dynamic response feet

Answer 24

– K2
– K4
– K1
– K3

Question 25

Match the following knee component with the appropriate K level:
– any
– mechanical knee with variable friction (hydraulic or pneumatic) OR microprocessor
– mechanical knee with constant friction
– mechanical knee with constant OR variable friction (hydraulic or pneumatic) OR microprocessor

Answer 25

– K4
– K3
– K1
– K2

Question 26

how often does insurance reimburse for a prosthetic device?

Answer 26

every 3-5 years depending on insurance

Question 27

the following components are for a _______
socket, pylon, foot

Answer 27

transtibial
ankle disarticulation

Question 28

the following components are for a ______
socket, rotator, knee joint, pylon, foot

Answer 28

knee disarticulation
transfemoral amputation

Question 29

the following components are for a ______
socket, hip joint, pylon, rotator, knee joint, pylon, foot

Answer 29

hemipelvectomy
hip disarticulation

Question 30

what are two methods for socket fabrication?

Answer 30

casting
scan

Question 31

TTA socket considerations:
pressure tolerant areas?
pressure sensitive?

Answer 31

calf, patellar tendon/knee cap
fibular head, end of fibula, end of tibia, shin bone, hamstring tendons

Question 32

TFA/KD socket considerations:
pressure tolerant areas?
pressure sensitive?

Answer 32

lateral and medial soft tissue, ischial tuberosity, posterior and anterior soft tissue

ASIS, greater trochanter, distal femur, pubic ramus, adductor tendon, pubic tubercle

Question 33

what are the two socket designs for TTA?

Answer 33

patellar-tendon-bearing (PTB) - indentation over patellar tendon, specific pressure points
total surface bearing socket (TSB) - distributed weight-bearing

Question 34

Quadrilateral socket TFA/KD:
– ________ for ischial tuberosity and gluts
– ______ same level as posterior shelf
– __________ 2.5-3 inches higher

Answer 34

– horizontal posterior shelf
– medial brim
– anterior and lateral brims

Question 35

Ischial containment socket TFA/KD:
– ______ more narrow
– _______ lower
– often see:

Answer 35

– medial-lateral walls
– anterior wall
– excessive anterior pelvic tilt

Question 36

Subischial containmen socket TFA/KD:
– “___”
– _____ must be able to tolerate weight bearing

Answer 36

– brimless (trimlines are lower)
– soft tissue

Question 37

a hip disarticulation/hemipelvectomy socket design encompasses what 3 structures?

Answer 37

pelvis
gluteal tissues
ischial tuberosity

Question 38

a hip disarticulation/hemipelvectomy socket design must provide:
– adequate ______ support
– _____ capture of pelvic movements
– ____,_____ suspension
– appropriate: (2)

Answer 38

– coronal
– sagittal
– secure, comfortable
– weight bearing surfaces, contours

Question 39

hip disarticulation/hemipelvectomy socket design accomplishes medial-lateral stability by:

Answer 39

compression on the contralateral pelvis

Question 40

what are the only two socket suspension designs that work for hip disarticulation/hemipelvectomy?

Answer 40

suction
vacuum

Question 41

a hip disarticulation/hemipelvectomy socket suspension:
– use of:
– trim lines above ____

Answer 41

– pelvic band
– iliac crest

Question 42

what are cons of using a thigh corset for suspension?

Answer 42

heavier
may facilitate pistoning
difficult to don

Question 43

what is a commonly used suspension system?
– what is one pro?

Answer 43

pin system –> shuttle lock system
– helps with pistoning

Question 44

what is a commonly used suspension system that uses a one-way valve and liner? One drawback of this system is pistoning can occur.

Answer 44

suction suspension

Question 45

what is a suspension system that uses a one-way valve and is worn without a liner? This is not for a first time user as the socket fit must be very snug

Answer 45

true suction suspension

Question 46

what are benefits of using a vacuum-assisted socket suspension system?

Answer 46

promote fluid exchange
reduce moisture build up
regulate volume fluctuations
increase proprioceptive awareness of limb
helps to control pistoning, may help with wound healing

Question 47

what are cons of using a vacuum-assisted socket suspension system?

Answer 47

expensive
heavier
noisy

Question 48

what is an option for patients who do not tolerate traditional prosthetic sockets?

Answer 48

osseointegration

Question 49

what are common complications of osseointegration?

Answer 49

infection
soft tissue irritation at stoma

Question 50

what is the timeline for osseointegration?
– 1st surgery:
– bone healing _____ months
– 2nd surgery:
– partial WBing _____ months
– finally _____

Answer 50

– fixture implanted
– 6 months
– abutment placed
– 6 months
– rehab

Question 51

what are options for suspension aids?

Answer 51

supracondylar trim lines
outer sleeve
thigh corset or other strapping mechanisms

Question 52

SACH feet (solid ankle cushioned heel) is a _______ foot

Answer 52

non-articulating

Question 53

single axis, multi-axial, dynamic response/energy storing, multi-axial dynamic response, hydraulic, and microprocessor are all examples of _______ feet

Answer 53

articulating

Question 54

SACH foot:
– k level:
– pros:
– ____ or _____ keel that extends to the MTP joints
– _______: allows for shock absorption and PF at loading response

Answer 54

– K1
– lightweight, inexpensive, low maintenance
– wooden or metal
– rubber heel

Question 55

single axis feet:
– k level:
– some _____ motion allowed
– controlled by interchangeable ____ and ____ bumpers
– no ____ or _____ plane movement
– no _______
– cons:

Answer 55

– K1
– sagittal
– anterior and posterior
– transverse or frontal
– energy return
– heavier, more maintenance

Question 56

multi-axial feet:
– K level:
– allows for some _____ and _______ to cope with uneven terrain along sagittal DF/PF
– cons:

Answer 56

– K2
– pronation and supination
– expensive, heavier

Question 57

who are multi-axial feet for?

Answer 57

people who function in areas with uneven terrain, active amputees, golfers, dancers

Question 58

energy storage/dynamic response feet:
– k level:
– leaf spring keel stores energy during _____ rocker and releases it during _____ rocker
– as cadence or activity level increases, ____ comes into play, resulting in _____

Answer 58

– K3
– 2nd ; 3rd
– more spring ; greater return

Question 59

multi-axial dynamic response feet:
– k level:
– combination of:
– closest to the ________

Answer 59

– K3
– articulated foot and dynamic response
– functional foot replacement

Question 60

Hydraulic feet:
– K level:
– multiaxial with:
– ______ return
– cons:
– smooth _____

Answer 60

– K3
– vertical shock absorption
– energy
– expensive, not as durable
– rollover

Question 61

Microprocessor/power feet:
– k level:
– identifies ____ and _____ after first step
– automatically provides DF during _____ phase that allow sufficient ground clearance
– _________ allows users to tuck both feet behind their knees when getting up from chair or sitting down
– automatically _____ foot for more natural appearance when seated

Answer 61

– K4
– slopes and stairs
– swing
– active ankle motion
– PF

Question 62

advantages of microprocessor feet:

Answer 62

provide push off
increased self-selected gait velocity
9.9% less energy expenditure

Question 63

disadvantages of microprocessor feet:

Answer 63

poor battery life
heavy (4.5 lbs)
expensive