Transtibial Prosthetic Components Flashcards
The majority of amputations are due to…
PVD/diabetes
what 3 pops have a higher incidence of diabetes
african americans
native americans
hispanic/latino americans
UE/LE amputations more common
LE
what is the most common amputation
transtibial
what is scar massage so imperative for amputees
more mobile scar tissue = less skin breakdown
what can you get for a pt with an amputated great toe or lateral digits
an insole with toe filler and carbon plate
what is another name for a midtarsal amputation
chopart
can you weight bear with a midtarsal amputation
yes, but base of support is very small
the more foot removed during amputation the greater the tendency for _______ contracture
equinovarus
for lateral toe(s) amputation, what kind of prosthetic do you need
simply a filler material such as lambs wool, sponge, or foam
for great toe amputation, what kind of prosthetic fo you need
a filler and a long steel shank in shoe to assist with push off
if all of your toes are amputated what kind of prosthetic do you need
shoe insole with metatarsal pad to relieve weight from met-heads, filler shaped from plastazote
what is the most common contracture with partial foot amputations
PF
syme’s amputation
ankle disarticulation
with symes amputations, the distal end of the limb is usually
bulbous
disadvantages of syme’s amputation
- poor healing
- heel can be too mobile or misaligned
- bone spurs
- prosthesis is not very attractive
- leg length discrepancy
advantages of syme’s amputation
- end weight bearing
- long lever arm
T or F: feet are made specifically for syme’s amputation
T: to minimize leg length discrepancy
entrance in a syme prosthesis
- removable window posterior or on sides
- expendable material for entrance from top
lengths of transtibial amputations
long = 50% of tibia or longer
mid-calf = 20-50% of tibia
short = less than 20%
what is the standard length of transtibial amputation
mid-tibial
two options for skin closure with TTAs
- posterior skin flap/ant closure
- fish mouth
the shorter the residual limb, the ______ ROM
less
ertl procedure
bone bridge between tibia and fibula
schon’s bridge
ertl adaptation with bone and screws
T or F: you can change some’s k-level
T: so when in doubt go more conservative and if they improve then you can up it
K1 feet (2)
- solid ankle cushion heel
- single axis
K2 feet (3)
- solid ankle flexible endoskeletal
- flexible keel
- multi-axial
K3 feet (4)
- flex foot, flex walk
- energy storing
- dynamic response
- multi-axial
T or F: K4 can have any foot ankle system
T
general cost of transfemoral prosthesis
6-90k
general cost of transtibial prosthesis
4-60k
is exoskeletal or endoskeletal prosthesis more durable
exo
both exoskeletal and endoskeletal prosthesis have these 3 components
- foot/ankle assembly
- shank
- socket
why are exoskeletal prosthetics not appropriate for growing children
they cannot be adjusted much
_______ has the socket and shank as one piece while with ____ components are added to one another
exoskeletal
endoskeletal
are endoskeletal or exoskeletal prosthetics heavier
exoskeletal
does endoskeletal or exoskeletal have a hard outer shell
exoskeletal
all prosthetic feet do what? (4)
1- provide a balance weight bearing surface
2 - help absorb force and stability during stance
3 - look like feet
4 - stimulate some motions of the foot during gait
this is the traditional foot for K1
solid ankle cushioned heel
*good for smooth and level surfaces
benefits of SACH foot (4)
1 - low cost
2 - many varieties
3 - light weight
4 - no moving parts
drawbacks of SACH foot (2)
1 - decreased forefoot stability in late stance
2 - not responsive to variations in terrain
what are benefits of stationary attachment flexible endoskeleton (SAFE) feet? (3)
1 - accommodates varied surfaces/terrains
2 - decreased torsional force on limb
3 - good roll over during stance
K3 feet keels are made of materials that combine _______ and ________. what does this allow for?
- stiffness and flexibility
- allows foot to be responsive and return energy
this foot is responsive to varied terrain, accommodates for walking incline, and allows for heel height adjustment
dynamic energy storing foot
T or F: running feet are used for general walking
F: they don’t have a heel so it is difficult to walk
what happens during gait if the feel height is too high
the toe does not hit soon enough so you have poor stability and pressure on anterior tibia
what happens during gait if the heel height is too low?
the toe hits too soon so the knee is forced into hyperextension and you have pressure on the patellar tendon
most common sockets are variation of the _____ socket
hard
*worn with socks or soft liners
more recently, hard sockets have been designed with window cutouts. what does this do?
makes them more flexible and responsive to muscle contractions
are flexible or hard sockets good for pts on dialysis. why
flexible because the insert can be removed to allow room for swelling
what is the standard socket for transtibial amputations?
patellar tendon bearing
where is a counter force applied in a patellar tendon bearing socket
popliteal fossa
the total weight bearing socket is a modification to the PTB socket that occured with the use of…
flexible inserts and gel liners
what are some pressure intolerant areas (4)
1 - tibial crest
2 - distal end tibia
3 - prox and distal head of fibula
4 - hamstring tendons
what are some pressure tolerant areas?
1 - femoral condyles
2 - patellar tendon
3 - medial tibial flare
4 - tibial shaft
5 - fibular shaft
6 - posterior compartment
what does the shape of a PTB socket accommodate for
adductors and hamstrings
*medial side is lower
T or F: hard sockets have an insert inside
F: you only use a sock
pelite liners are used primary in a ______ socket
PTB
*before silicone gels and urethane liners
T or FL pelite liners have identical pressure tolerate and relief areas that the socket will have
T: they are formed on the positive cast of the residual limb
can pelite liners be removed for cleaning
yes
T or F: pelite liners have to be positioned in the socket to precisely match the contours
T
gel and urethane liners form a ________ between the limb and socket
suction… so they can also be used as a means of suspension
T or F: gels and urethanes come in varied thickness
T
what is the problem with a gel liner
they can “hide” skin problems so you are not aware of it until it is really bad
what are some advantages of gel/urethane liners
- disperse forces
- more comfortable fit
- soft skin
- suspension
- helpful for pts with fragile skin
- true total contact with prosthesis
2 ways to take an impression for a prosthesis
casting
scanning
what is the good thing about scanning over casting
scanning takes the human element out of it and you can also create the same exact prosthesis years later
what are prosthetic socks used for
to adjust to fluctuations in residual limb volume
T or F: the residual limb often shrinks during therapy
T
T or F: residual limb volume usually does not change throughout the day
F: it is not uncommon for it to reduce which means you may need to add a sock
T or F: it is not uncommon for pts to regularly wear 3-5 ply socks
T
a new socket is normally required when pts need _______ ply socks
10-12
how are socks applied
the thickest is put next to the skin and then you follow with thinner socks
many amputees wear a nylon sheath between their limb and socks. why?
to help with perspiration and reduce shear forces on skin
with pelite liners, socks are work where? what about w/ gel and urethane liners?
pelite = between the limb and pelite
gels/urethane = outside of the liner
how should you wash socks
hand wash, mild detergent, blotted dry, and dried flat
or gentle cycle machine wash and dry on low (updated ppt)
flexible inserts accommodate for…
expansion (ex: muscle contraction)
are flexible inserts more common in above or below knee sockets
above knee
what are some suspension methods for below knee amputations (5)
1 - waist belt fork strap
2 - PTB cuff
3 - PTB supracondylar
4 - PTB supracondylar suprapatellar
5 - suction or vaccum
a pin locking system may not be a good option if the pt has a lot of…
scar tissue
if a pt needs more _____ pinlocking may be a good option
ROM
is osteoarthritis more prevalent in the intact or residual joints?
intact
T or F: long term prosthetic use (TTA) with a proper prosthetic fit does not predispose wearer to premature degenerative arthritis
T
amputees are at an ____ risk for back pain
increased
