Flashcards in Upper Extremity Prosthetics Deck (57):
What movements are required to operate a standard trans-radial prosthesis?
Biscapular abduction and Gleno humeral flexion
What is the prehension pattern most frequently used by prosthetics hands?
What is the proper Orientation when taking an impression for all levels of trans-radial amputations
Neutral Pro-supination, 90 degrees
Which muscle acts in the same way a control cable pulls on the thumb of the terminal device?
Extensor Pollicis Brevis
Which muscle is not a forearm flexor?
d. Pronator Teres
What muscles comprise the rotator cuff?
Teres Minor, Supraspinatus, infraspinatus, subscapularis
How many positions does a positive locking hinge have?
The correct location of the cross point on a standard Trans-radial figure of eight prosthetic harness is:
Inferior to C7 toward the sound side
Which muscle is primarily responsible for scapular abduction?
weakness of the Serratus Anterior causes what?
A split housing cable is required when using?
Body Powered elbow hinges
What are the Elbow flexors
Brachialis, Biceps Brachi, Pronator Teres
What is the strongest elbow flexor?
What is the function of the Biceps Brachii
flexion of elbow and supination of forearm
The Median nerve innervates
What is the function of the Brachioradialis?
Flexion of elbow with forearm in mid-position (halfway between supination and pronation)
The main innervation for the elbow flexors
What design feature is necessary to allow full pronation-supination in a trans-radial prosthesis?
Trimlines that exclude the epicondyles
The Muenster type self suspending prosthesis
-Limits range of motion no more than 70%
-Used for short to very short trans-radial amputations
-Utilizes tight AP interface fit
-Cannot be donned by pushing in
The Northwestern University self suspending prosthesis
Can be used by bilaterals because it is designed for push in donning.
What nerve is called the "funny bone" because of its surface position posterior to the medial condyle?
The primary function of the anterior suspension strap in a standard figure 8 TR harness is?
To act as the main suspensor; The strap helps to suspend the prosthesis against axial loading; Prevent rotation of the prosthetic socket on the residual limb during prosthetic use.
The Uppers for a single axis transradial hinge are attached to what harness element
What movements are necessary to operate the positive locking elbow on a body powered trans-humeral prosthesis?
-Slight shoulder depression
what are appropriate devices for children
CAPP hand - "aligator", "Helper"
Voluntary Closing terminal devices
normally opens when the amputee is relaxed, are closed by pulling the control cable
Voluntary Closing terminal devices functions
-Close with cable pull and open by spring force
-Have no rubber bands
-Provides graded prehension
-Can be locked, but releasing that lock requires enough force to break a fragile object.
In the Bowden cable system, a stainless ferrule is located at?
both ends of the cable housing to finish the cut end of the housing.
What is the goal of the Cross Back Strap?
To prevent the upward migration of both control attachment straps in the case of the bilateral harness; also helps to keep the path of the control attachment strap positioned lower on the back
what is the location of the cross back strap?
The Cross back strap passes horizontally across the amputees back and terminates at the distal end of the control attachment strap; The path of strap should run between the spine and inferior angle of the scapula
what does the cross back strap do?
helps to maintain the posterior intersection of the harness below spinous process of C7
what is a indication for a cross back strap?
when there is axilla loop discomfort on the nonamputated side; this discomfort is caused by a vertical compression of the pectoral, teres major, and latissimus dorsi tendons by the axilla loop during strenous prosthetic usage.
In a scapulothoracic amputee, what motion can be used to operate the prosthesis?
The infraspinatus performs what action?
Lateral or external rotation of the arm, extension of the humerus, and stabilizes the shoulder
Shoulder disarcticulation tend to have more difficulty with force or excursion?
Excursion needed to operate the prosthesis .
what are the benefits of a shoulder saddle harness?
Increased comfort in axial loading, reduce pressure on the axilla (however, does not improve excursion with biscapular abduction.)
Definition of amelia
complete absence of a limb
What epiphysis contributes most to the longitudinal growth of the UE
The distal harness
What muscle performs elevation of the scapula?
Trapezius; it also causes adduction, lateral upward rotation of scapula and depression.
What amputation level would flexible elbow hinges be most appropriate?
Long Transradial and lower (some pronation and supination)
Where do flexible elbow hinges attached?
attached proximally to the triceps pad and distally to the prosthetic forearm and should allow prosthesis rotation of at least 50% that of the anatomic residual forearm rotation.
what do flexible hinges do?
Flexible hinges permit active use of the residual forearm rotation, minimizing the requirement for manual propositioning of the terminal device by the amputee.
What about of supination and pronation should be preserved with a wrist disartic prosthesis?
At least 50%
Supination and pronation of the forearm occur at which joint?
Proximal radioulnar joint- the radius rotates around the ulna.
In mid length TR amputee, which muscle is missing
What is not part of a below elbow figure of 8 harness ?
Lateral suspension strap
If a below elbow prosthesis is harness with a split cable housing, which prosthetic joint has most likely been utilized?
outside locking, possibly step-up hinges
Which wrist unit provides the greatest ROM for a bilateral below elbow amputee?
Wrist flexion unit/sierra wrist type
What modification is made to the figure of 8 harness for bilateral below elbow patient?
A Cross back strap is added
What muscle is the main supinator of the forearm?
Biceps Brachii (more powerful than the supinator muscle.
When the elbow flexion attachment of an above elbow prosthesis is moved toward the TD, what mechanical effect will it have?
It will decrease the force required, but increase the excursion needed
What externally powered elbow unit is not typically adaptable to the switch control in a harness?
When are step up elbow hinges indicated?
-Very Short to short BE
-Weaker flexion power
-2:1 excursion ratio
-(No special harnessing required)
Polycentric elbow hinges are used at what level of amputation?
what is Electrodactyly?
Involves the deficiency or absence of one or more central digits of the hand or foot and is also known as split hand/ split foot malformation
Lyre shaped finger hooks
These hooks have symmetrical fingers for cylindrical grasp on objects, such as bottles, cans and other round objects.