Upper Limb Intro and Body-Powered Prosthetics Flashcards
What is a prothesis/prosthetic/prosthetic limb? What field is it a part of?
Artificial device extension that replaces part or all of a missing body part.
Biomechatronics.
What are design considerations for artificial limbs? (7)
- Function vs form
- Weight
- Usability/Comfort
- Durability/Repair
- Power sources
- Control system
- Cost
What are reasons for amputation based on age range?
0-15: congenital deformity or tumor
14-45: trauma
60+: amputations rare, usually for tumor or disease
What are the levels of amputation?
Hand - Below elbow (5)
- Transphalangeal amputation: thumb/fingers
- Transmetacarpal amputation: through metacarpals
- Transcarpal amputation: through carpal bones
- Wrist disarticulation: between carpals and radius/ulna
- Transradial amputation: below-elbow (long, medium, or short)
What are the levels of amputation?
Elbow - Shoulder (4)
- Elbow disarticulation: through elbow joint
- Transhumeral amputation: above elbow
- Shoulder disarticulation: through shoulder joint
- Interscapulothoracic disarticulation (forequarter): remove entire shoulder
What is residual limb?
Remaining portion of amputated limb
Relief? Buildup?
Relief - concavity within the socket for areas sensitive for high pressure
Buildup - convexity for areas tolerant to high pressure
Myodesis? Myoplasty?
Myodesis - Direct suturing of residual muscle or tendon to bone/periosteum
Myoplasty - Suturing of agonist-antagonist muscles pairs to each other
Terminal device? Prehensile?
Terminal device - distal part of a prosthesis that substitutes for the hand (prosthetic hand, hook, or other)
Prehensile - grasp
What are pros (5) and cons (4) of body powered?
Pros: moderate cost, moderately lightweight, most durable, highest sensory feedback, different prehensors available
Cons: needs body movement, most harnessing, ugly, increased energy expenditure
What are pros (5) and cons (5) of battery powered?
Pros: no harnessing, least body movement, more function, stronger grasp, moderate cosmesis
Cons: heavy, expensive, maintenance, limited sensory feedback, time for training
What are the components of an upper limb prosthetic? (4)
- Socket: inner socket to fit the residual limb and second outer wall fabricated from plastic or graphite composite
- Suspension: holds prosthesis securely to the residual limb
- Control cable system: controls function
- Terminal device: tries to replicate grip
What are 3 types of suspension systems?
- Harnessed-based system: most used (shoulder-saddle with chest strap)
- Self-suspending sockets: proper fit suspends itself
- Suction sockets: attaches by a vacuum between stump and prosthesis
Advantage and disadvantages of each suspension system?
Harness: + simple, adjustable, durable; - pressure causes discomfort
Self-suspending: + ease of use; - limited lifting capacity
Suction: + secure, no straps; - harder to put on
What are Bowden cables?
Flexible cable used to transmit mechanical force by the movement of an inner cable relative to a hollow outer cable.
Transmits a pulling action
What movements are used to control cables?
-Glenohumeral forward flexion
-Biscapular abduction (chest expansion), mutual protraction
-Glenohumeral depression/elevation, extension, abduction
-Nudge control
Different types of terminal devices
Active: hands, hooks. Voluntary opening (closed at rest) or voluntary closing (open at rest)
Passive: Hammer, saw, baseball, fishing
