UE Flashcards
Difference between figure 8 & 9 harness. When is a figure 9 used instead of a figure 8?
fig 8 has anterior suspensor & is attached to a cuff strap
fig 9 is a cable control system only, no suspension mechanism
use of cross back strap
better excursion available
keeps control strap inferior on scapula
less migration
more TD opening is possible
inverted y strap
function = transmit vertical forces from cuff to axilla loop
suspension
helps control rotation
anterior suspensor strap
function = main suspensor of px stability against downward pull
location = originating at ring, through deltopectoral groove to junction of inverted y
control attachment strap
function = transmit excursion or tension from harness to move cable operate TD
location = origin at ring, passes inferior to spine of scapula & proximal to inferior angle of scapula on amputated side, terminating at hanger cable
cross point
function = continue axilla loop to anterior suspensor & control strap
location = to provide the best mechanical advantage the crosspoint should be located just inferior to the spinous process of C7 toward sound side
which muscles primary responsibility is for scapular abduction
serrates anterior
the retainer is located in the proximal 1/3 of the TR px because
to allow maximum excursion with humeral flexion
in the conventional WD px, suspension is provided by the
fig 9 harness
in the TR px, the cross bar is located mid-humerus (or up to 1 in distal) in order
to allow full elbow flexion
in the long TR px, the typical trim lines are
below the epicondyles to preserve pronation/supination
when fabricating the TR px, what measurement should match the lateral epicondyle to thumb tip on the sound side?
supination
the polycentric hinge is used for what type of patient?
short TR
when fitting the TR px, what measurement should match the lateral epicondyle to thumb tip on the sound side?
the lateral epicondyle to the tip of the TD on the px
to fit the triceps cuff, the prosthetist must take circumferential measurements where?
1 in pros. to the cubital fold & around the deltoid insertion
the total ROM available in forearm rotation (pronation/supination) is
170*
purpose of the fig. 8 harness
suspension & provides reaction point for excursion
the TR fig 8 anterior suspensor strap, which runs down to the delta-pectoral groove, is attached to what
the inverted y
the self-suspending TR socket suspends in what manner?
ML pressure, assisted by AP pressure
the self suspending socket is most commonly prescribed with what type of harness?
fig 9
the control attachment strap on the TR harness does what?
activated the TD
the step up hinge px is indicated for what type of amputation?
burn patient with limited elbow flexion
very short BE
BE amp where stump disappears into cubital fold
in the medium length TR there can be some residual pronation because
pronator teres is still largely intact
prime move for elbow flexion
brachialis
greatest disadvantage to the amputee using a step up hinge:
loss of flexion power in forearm
a component that locks out forearm pron/sup when the TR has less than 50% forearm remaining
rigid hinges
in what does the inverted y in a fig 8 harness do?
suspension
transmits axial loads to the shoulder
attaches to the proximal tabs of the triceps pad
the center of the fig 8 harness should be where to produce max excursion?
up to 1 in to the sound side
what are the 2 controls in the dual control system of the body powered TH
TD activation, elbow flexion
the purpose of the skirting in the shorter AE is what?
control internal/external rotation
the location of the AE forearm lift look is moved distally. what will this do the the force and excursion required for elbow flexion?
decrease force & increase excursion
elbow lock control is activated through what movement?
humeral extension, abd, and downward rotation of the scap
what is the possible cause of external rotation of the AE px during humeral flexion?
humeral retainer too far lateral & lateral suspension strap attach too far posterior.
a TH amputee w/ dual control (2 fx, single cable) & a homer 5xa hook. if the measured force at the control strap is 7 lbs. to open the hook & 9 lbs to flex the elbow, what will happen if the amputee attempts to get a piece of candy from a table to his mouth with his px?
the TD will open; he will drop the candy
if the TH amputee cannot fully flex the px forearm because of an excursion limitation, they would be aided least by:
moving the elbow flexion attachment (forearm lift loop) distally
control system efficiency in UEP is measured at the _________ & the _______.
TD; control strap
external movable sheave type excursion amplifier is used with what type of px?
SD
what does the nudge control enable the amputee to do?
lock & unlock the elbow by pressing lever w/ the chin
an AE amputation w/ 30% humeral length should be fitted with:
an AE px in which the timelines are extended over the scapula & medial to the deltopectoral groove to increase rotational stability
the shoulder disarticulation px is operated primarily by what control motion?
scapular abduction
one action of the deltoid is to:
adduct the GH joint
in order to flex the elbow, the TH amp w/ a fig 8 harness
unlocks the elbow & flexes the GH joint
if the application of a single, continuous housing were made on the TH px as it is on the TR, the amputee would lose:
elbow lock control
the polycentric (rigid) hinge is used on which type of amputees?
short TR
approximately _____ inches of excursion are required to operate a dual control system
4.5
when operating a voluntary opening TD close to the body, the TR or TH amputee uses ______ as the source of excursion & force
scapular abduction
the correct location of the cross point on a standard TF fig 8 harness is
inferior to CF toward the sound side
which muscles primary responsibility is for scapular abduction?
serrates anterior
as the elbow flexion attachment is moved distally on a TH px:
increases excursion response
a cross back strap is used on a TH px to primarily
increase control cable efficiency
which px elbow requires the split control cable?
outside locking hinge, geared step up hinge, stump activated locking hinge
which muscle is both a primary elbow flexor & a supinator:
biceps
which work together in scapular abduction:
serrates anterior & pectoralis minor
in a scapulothoracic amp, what motions can be used to operate the px?
chest expansion
which muscle does not internally rotate the humerus?
infraspinatus
for which type of amp is external or outside locking joint designed?
elbow disarticulations
elevation of the escalation is accomplished by the
trapezius
what should function will be lost if the middle section of the deltoid is impaired
abduction
a unilateral BE px patient c/o the axilla loop of his harness is uncomfortable. the most common reason for this complaint is that the cross point is:
too close to the amputated side
what is not an advantage of the myoelectric px system over a cable driven one?
does not provide inherent sensory feedback
the primary advantage of a voluntary closing TD is
graded prehension
the main forearm supinator of the forearm is the
biceps
an excursion amplifier incorporate on a control system provides increased cable excursion at the expense of
requiring more force
when the elbow flexion attachment of the AE forearm is moved toward the TD, it will have what mechanical effect?
increase force required, decrease excursion required
