Prosthetics (Exam 4) Flashcards
UE Dilemma
limited UE amputations/yr (15,000 per yr)
difficult for a prosthetist or therapist to specialize in due to limited #
Causes of
UE:
Trauma
Congenital
Disease
LE:
largely a result of disease
(cancer primary source, diabetic neuropathy, flesh eating bacteria, infection, gangrene)
New Amputees
UE:
Trauma - primary
Cancer - second
Congenital - third
Amputation Locations
Forequarter - whole glenohumeral joint is gone and goes up into scapular region
Shoulder disarticulation - right at the glenohumeral joint a bit more distal than forequarter
Trans-humeral - sometimes farm injuries
Elbow disarticulation - above or right at joint but anything below is transradial
Trans-radial - MOST COMMON, below elbow and goes across the radius
Wrist disarticulation - radius and ulna separated from the carpal bones
Transphalangeal - fingers
Basic Prosthetic Goal
- Provide appropriate fx and appearance to increase INDEPENDENCE with ADLs and improve QUALITY OF LIFE
- Goal depends on where you are and depends on doctors and hospital
- Lots of psychosocial to work on, self esteem, help with adaptation process, it is up to us to get with the doctor and prosthesis specialist
- Get functioning as normal as possible right away but we need to come at it from all directions
- Prosthesis is not always the best option depends on what the pt wants
Priorities and Challenges
- Pt/caregiver education
- Peer support
We need to provide them support through peers and support through those who have experienced this.
Our job is to show them that they can go back to occupations
Delineate prosthetic expectations
Rebuilding proprioception - diff with a new limb, have to have this b/c brain has to get input to match and use that to strengthen Mm that did not have to work before
Establishing independence and confidence
Establishing good habits
Etiology
- Traumatic (MVA, Farming, burn)
- Congenital
- Tumors
- Vascular
- Infection
They could have flashbacks, must pull out psychological coping mechanism
When born with it there is not the psychological component and they don’t necessarily need it but for children it could be necessary to provide a remapping of the cortical homunculus and for spine development
(a lot can be functional without it)
Infection and cancer could come back so have to be careful with type and it could be delayed until they are cancer free or infection is healed
Prosthetic Design - choosing options
- The actual physical evaluation of the pt and the residual limb is a critical step in the recommendation of the prosthesis
- We have to look at the integrity of the tissue
- sometimes there is not a lot of subcutaneous tissue
not the best set up for a prosthetic, no cushion - how much of a stump is there
- what are the occupational needs
- expectations can differ from reality
ex: anytime there is an electronic component, they
can not get it wet and they are heavy pulling on
spine and neck
- sometimes there is not a lot of subcutaneous tissue
Advancements are working on artificial skin that sends sensations to the brain, right now you can not feel
Basic Structure of Prosthesis
Socket - suspension interface for stump to go down into, usually lined with silicone or padding and have a suction
Socket interface - extremely flexible plastic material, improves socket comfort
Terminal device - distal end of prosthetic (hook, hand)
Prosthetic Options
No Prosthesis
Oppositional Prosthesis - like a myoelectric but it just opens and closes hand
Body powered - cable operated (Sunni’s fav) you have to move your body and a cable system moves hand usually scapular movement when above elbow and use of elbow movement when below elbow or use a hook to open and close
Externally powered - battery powered and electric, myoelectric, body is not controlling opening and closing it is happening from electro current and battery
Hybrid - combined technology
Activity Specific
Multiple Prosthesis
- Financial is another issue and sometimes pt has multiple prosthetics
Option should be pt driven:
NOT b/c of non-coverage
NOT b/c of lack of access
Reasons:
- Limited perceived functional benefit
- Reduced sensory input
- Comfort
- Hot and or heavy
*Decision needs to be up to the pt b/c there are so many ways we can adapt (don’t have to have UE)
NO Prosthesis - referral to OT
one handed techniques
posture and ergonomics
yearly follow - up to ensure functional requirements
are met
scar massage and desensitization - just lost a limb and cortical representation is not matching
Weight bearing and exercise and stretch, especially if it is a transradial, shoulder needs to be stretched, skin integrity and strengthening of scapular stabilizers, train in one handed technique, posture, ergonomics
Oppositional Prosthesis
(Passive)
Benefits:
* Provides aesthetic appearance
* Light weight and simple
* Functions: opposition
holding objects
restore body image
* Proprioceptive feedback
Limitations:
- No active prehension
- High cost for custom
- Durability - not the greatest
- Pt can have unreal expectations for cosmesis
Just for looks, does not do much, still usable, can implant hair and paint fingernails
Does allow you to use thumb as a passive hook, easy to use, does not require using a cable or isometric contractions like the EMG prosthetic and does provide proprioception
Body - Powered Prosthesis
(Cable driven)
Relies upon gross body movements captured through a harness (shoulder girdle motion is controlling the opening and closing of the hook)
Benefits:
- Moderate cost and weight
- Durable
- Environmentally resistant
- Proprioception through harness system
Limitations:
* Grip strength or pinch force (strong enough to do most
activities and can lift a bale of hay, but not as strong as
the myoelectric and if you need a stronger pinch, you
can change out the tool
* Restrictive & uncomfortable harness
* Requires muscle power and excursion
* Poor static and dynamic cosmesis
Flexing shoulder opens terminal end
Extending shoulder closes terminal end
Environment resistant - person works as a mechanic, spills stuff on it (okay) better option you can get it wet
People don’t want a hook but it is very functional
Body Movements Needed for Prosthetic Control
Transradial - uses elbow flexion and extension
Transhumeral - shoulder flexion and extension
- Scapular - change directions or lock/unlock
Externally Powered Prosthesis
(Electrically powered or Myoelectric)
- Powered by a battery
- Myoelectric signals
- Controlled by various input methods
Myoelectric signals - on inside of socket are sensors
transradial sensor on flexor tendon closes terminal end
with isometric contraction and on extensor tendon
opens terminal end with isometric contraction
* All they need is electrical activity that is perceivable
by EMG to do it
Most are covered by a skin like glove but they tear and get dirty and should not get wet, look beautiful but don’t hold up well, do have stronger grip force
Benefits:
- Stronger grip force
- Moderate or no harnessing
- Minimal energy expenditure
- Least body movement to operate
- Moderate aesthetics
Limitations:
- Heavier
- More expensive
- Limited sensory feedback
- Extensive therapy training
- Don’t get proprioception, just get weight of device pulling
Muscle Groups:
Transradial - wrist flexors and extensors
Transhumeral - biceps brachii
triceps brachii
deltoid
Hybrid Prosthesis
- A single prosthesis in which 2 or more technologies are combined
- Less weight than fully powered system
- More grip strength than a body powered system
Ex: Elbow = body - powered
Hand = externally powered
Benefits:
- Simultaneous control of the elbow and terminal device
- Reduced weight compared to all electric
Limitations:
- Less pinch with cable controlled terminal device
- Difficult to lift battery powered terminal device
Advancements
1) Target Muscle Reinnervation (TMR)
* instead of operating with battery pack or cable, we
are starting to use our anatomy and hooking up to Nn
ex: shoulder is in close proximity to plexus and our Nn
can serve as cables and operate an electronic
device - we are energy, EMG implanted into pec
Mm, anything after proximal trunk is gone but
proximal plexus is still there
2) Pattern Recognition - computer software translates muscle activity into prosthetic movements, many electrodes and heavy, lots of stuff attached
3) Multi-articulating hands - goal is to increase prehension
Partial Hand Options
- Amputation levels from a single finger tip to complete transcarpal loss
- Silicone Restoration
- Opposition Prosthesis
- Mechanical Systems
3 Above - Static - restores look made of silicone, can change thumb position in anyway that pt needs for occupation, can change them out
- Powered Finger Systems - this is a base device and would have glove or sleeve on top of it, now can change position of wrist and it will close
Challenge
Without proper therapy and a TEAM approach, the benefits of prosthetic acceptance and success are limited
If they want it in the beginning we need to make sure they have successful therapy
Phases of Rehabilitation
Pre Prosthetic
- Pre surgical
- Post surgical and in fitting process
Post Prosthetic
* After prosthetic delivery
Reinforce realistic expectations
EMG Training
Develop 2 antagonistic Mm with acceptable EMG output (10 mv per min)
Develop EMG separation between the muscle sites ( 10mv minimum)
Develop stamina in each muscle
- Myoelectrical terminal device reads the EMG signal of the pt
Unilateral Independence
- One handed tech such as shoe tying, cutting, and carrying
- Adaptive equipment is an option, but sometimes it seems to slow the post prosthetic phase
- Always strengthen no matter what - core, scapular stabilizers and PROM should come early b/c we don’t want them getting tight
Rehabilitation Orientation
- Post Delivery
- Donning of prosthesis
- Control of components
- functional training
- occupational performance - does prosthesis allow for
full productivity of individual at his or her chosen
occupation?
Rationale
Preprosthetic training focuses on promoting readiness for the permanent prosthesis including promoting skin healing, conditioning, preventing contractors, controlling edema, and providing desensitization to the residual limb
