TF Flashcards
even pressure is applied over the entire RL surface by a socket that is:
shaped to relieve hard areas and compress soft areas
how do you calculate the gross AP for an AK Quad socket from patient measurements?
Net AP + 1/2”
to accommodate or prevent an adductor roll in a TF fitting, the prosthetist must
bevel the medial wall outward at a 45* angle, & round the bevel over the medial brim while extending the bevel 1” into the socket
the AP measurement is the distance between the
adductor longus & the ischial tuberosity
an important biomechanics reason for placing the lateral wallow the TF px in adduction is
to place the hip abductors on stretch
which muscle on the medial quadrant of the RL is most commonly transected in a TF amputation?
adductor magnus
when taking px info for a TF amp who will be fit with a quad socket design, why is the musculature at the gluteal fold recorded?
to establish the posterior to medial wall angle
what muscle, that is a primarily a flexor of the knee, becomes a major knee extender in TF amp?
biceps femoris
if the ML dimension of the TF quad socket is too large:
the ischial tuberosity will move laterally the ischial seat
the prosthetic single axis foot DF bumper substitutes in part for the
Gastrocnemius
the lateral wall of the TF socket
is adducted to stabilize the femur
the knee type with the MOST inherent stability is the
manual locking knee
a SACH foot with a soft heel cushion will
enhance knee stability for the TF px
during TF gait in stance phase the hip abductors cause the distal aspect of the femur to
translate or move laterally to stabilize on the lateral wall
name a disadvantage of a weight activated, single axis, constant friction prosthetic knee
must unweight to get knee to bend
what 2 joint, superficial muscle is responsible for hip flexion & knee extension?
rectus femoris
what will cause the ball of the foot to be more than 1.5” off the ground at heel contact?
excessive socket flexion
if a TF amputee with a very short RL attempts to use it for lateral stabilization what will happen?
they cannot tolerate the increased & unusually localized pressure
when the socket is aligned with initial flexion it lengthens the amputees hip extensors which gives the amputee
greater control of knee stability during the entire stance phase of the walking cycle
what does a stiff heel cause at heel contact?
external rotation
Ping the foot would have what effect on the TF px?
stabilizing the knee at heel strike, preventing excessive heel compression
knee flexion in the hip disarticulation px is initiated with the
posterior hip bumper
a pt is c/o crotch pressure & you have already lowered the medial tramline 1/4”. what should you do?
A could be too large. Ischium is slipping off the seat. pad anterior wall
if a px has insufficient relief for the gluteus, when would it be most evident?
Midstance
a pt comes in c/o lateral distal pressure, what would fix this?
outset the foot w/ relationship to the ischium
a pt has firm gluteal musculature. how best to accommodate this?
larger medial-posterior wall angle
in a hip disarticulation, what is standard alignment?
line through hip knee axis falls 1.5 “ posterior of the foot
if a patient is amputated just above the femoral condyles, which muscle would retain its full strength?
adductor magnus
during heel strike & foot flat is the reaction line located with relationship to the hip & what muscles are firing?
anterior & hip flexors
during standing w/ weight equally distributed the reaction line passes where in relation to the hips?
posterior, medial
from mid stance & heel off the hip is _____ & knee _____ to reaction line.
hip posterior, knee moves from anterior to posterior
what is the best way to correct an adductor roll?
pull the adductor roll into interface & build up w/ pads until eliminated
scraps triangle
sartorius, adductor longus, inguinal ligament
at what point does the anterior wall in a TF px undergo the most loading?
heel strike
lateral trunk bending may be caused by all of the following except:
knee friction too great
what chronic problem arises from an interface that does not provide total contact?
verrucose hyperplasia
what gait deviation would arise from inadequate interface flexion?
unequal step length
the hip joint lies where with relationship to the trochanter?
anterior & superior
the acetabulum is formed by what bones?
ilium, ischium, pubis
the gluteus medium is most active during
midstance
the toe of an AK px rotate externally at heel strike. which is a major case of this problem?
plantar flexion resistance too firm
to minimize lateral trunk bending subsequent to unilateral hip abductor weakness, it is best to use:
a cane on the uninvolved side
the body’s center of gravity reached it’s highest point at
midstance
during normal human locomotion between heel contact & foot flat, the floor reaction force tends to cause which moments at the hip & knee?
hip & knee extension
if the sciatic nerve was severed at the level of the lesser trochanter, muscle function will not be impaired at the
hip joint
which muscle inserts on the lesser trochanter?
iliospsoas
in a hip disarticulation, the major function of the iliac crest is
suspension
during ambulation, instability of the knee at heel strike with a hip disarticulation may be caused by
heel wedge that is too hard
during dynamic alignment the patients trunk bends laterally toward the amputated side indicates what issue?
knee too medial
which adductor is always transacted in KD?
gracilis
a burning or stretching sensation near the ischial area while sitting is most likely caused by
too narrow AP diameter
its with short ak, generally exhibit lateral trunk bending due to
loss of abductors
which muscles decelerate the leg before heel strike
biceps femris
primary function of the gluteus medium is to
maintain lateral stability of the pelvis
when the shoe counter fits too tightly on a sach foot, what happens
posterior lean of pylon
