i-limb is intelligent limb

1. PRESENTER : DR M PERTIN
RIMS,IMPHAL(INDIA)
i-Limb Hand
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2. History of Prosthetics
Oldest known splint: 5th
Egyptian Dynasty (2750-2625
B.C.)
 500 BC : Earliest known written
reference on artificial limb by
Herodotus, Greek historian
300 B.C : Artificial limb made of
copper and wood leg unearthed
at Capri, Italy in 1858
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3. 1529, Ambroise Pare, French surgeon introduced
amputation – 1st
scientific prosthesis
1863, Dubois L Parmelee , New York City : socket
1898 :Dr Vanghetti invented an artificial limb that
could move with muscle contraction
1946 : Suction sock for the AK prosthesis at
University of California (UC) at Berkeley
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4. History of myoelectric prosthesis
Myoelectric control (1945) : 1st
implemented by Reinhold
Reiter, physics student at Munich University; prototype
demonstrated
1948 : Production stopped due to lack of fund
Late 1950s & early 1960s : USSR, United Kingdom, USA,
Europe and Canada, after invention of transistors
1964 :1st
commercial myo-electric arm; Central Prosthetic
Research Institute, USSR; distributed by the Hangar Limb
Factory, UK
1970s : rapid development; advances in battery and magnet
technology; reduction in motor size and weight
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5. Non prehensile Prehensile
• Touching, feeling
• Pressing down
• Tapping
• Stirring
• Vibrating cords of
instruments
• Lifting/pushing with
hand
 Precision grips
• Palmar pinch
• Tip pinch
• Lateral or key pinch
• Three jaw chuck
 Power grips
• Cylindrical grip
• Spherical grip
• Hook
Hand functions
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Psychosocial roles : Gestures, caressing, communication, and sensation.Psychosocial roles : Gestures, caressing, communication, and sensation.

6. Ideal prosthesis
Function - simple, meet user’s need and
dependable
Comfort - fits well, easy to don and doff, light
weight
Cosmesis - natural look both at rest and
` functional activity
Fabrication - easy and widely available
Economics - affordable and worth cost
Prosthetic device that provides the best prehension and functional movement is an
important goal
Prosthetic device that provides the best prehension and functional movement is an
important goal

7. Prosthetic options
 Passive prosthesis
 Body-powered prosthesis
 Electrically powered prosthesis
 Hybrid prosthesis
 Activity-specific prosthesis
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8. Passive prosthesis
Passive :
No moving
part/function
Cosmesis
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9. Body powered prosthesis
Restriction from harness
in ROM and function
Non use of prosthesis
Body powered:
Operating force from
muscular effort remote
from the amputation site
Durable
Weigh less than their
electrical counterparts
Mechanics depend
on proprioceptive
feedback and pull
through the harness
system
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10. Externally powered prosthesis
Externally powered :
• Operating force from
outside the body
- Pneumatic
- Hydraulic
- Battery
Pectoralis, Deltoid-
ant/post, Infraspinatus,
Teres major, Biceps,
Triceps, Wrist
extensors/flexors
 Controls :
 Myo-electrodes
 Switches
 slider-type input devices
 force-sensing resistors or
touch pads
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11. Hybrid prosthesis
Combination of body and
electrically powered
types
At or above elbow
amputations : Body-
powered elbow and
electrical terminal device
and wrist
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12. Activity specific terminal devices
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13. Terminal devices :
Passive : No moving part/function
Cosmesis
Passive hand, Mitts
Prehensile :
Hooks – Voluntary opening/closing
Hands - Voluntary opening/closing
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14. i-Limb Hand
Bionic Hand
First commercial active prosthetic
3 variants : I-Limb Pulse, Ultra & Ultra revolution
Developed by David Gow of the Scottish National
Health Service
Built by Touch Bionics™
Major advance on previous hooked limbs.
Became commercially available in 2007
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15. Hand
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16. Wrist
Multiple positions of flexion and extension in set
increments
Quick detachment for changing between terminal
devices
Flexible mode: Natural movement with progressive
resistance with a spring-loaded mechanism that
returns the wrist to a neutral position
Rigid mode: Locks the flexion or extension in
increments for holding and carrying objects
360-degree rotation, with stops at multiple positions
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17. Processor and electrodes Battery
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18. Basic descriptions
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19. How It Works
Sensors are imbedded in the forearm
Impulses from the brain are read
A microprocessor controls each finger individually
Determines the amount of force necessary to grasp
an object
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20. How it works
 Electrode mounted on
residual limb.
 User tightens muscles, this
generates an electrical
impulse.
 Impulse sent to computer
on board the prosthetic.
 Based which muscles are
fired the hand will open or
close.
 Requires some
prepositioning of fingers
for some actions.
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EMG electrodes EMG amplifier/processors

21. TMR
Targeted Muscle Reinnervation
Developed by Dr Todd Kuiken
Ligated nerves rewired to adjacent muscles :
amplification of nerve signals
Creation of new EMG sites:
 Transradial – forearm
 Trans humeral - residual upper arm
 Shoulder disarticulation- chest
• Controlled by muscle contractions
Muscles serve as biological amplifiers of motor
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22. Features
3 degrees of freedom :
 Elbow flexion/extension
 Wrist supination/pronation
 Terminal device opening/closing
• 5 articulating fingers moving independently at joints
similar to natural joints
• Near normal dexterity :
• Can hold a single sheet of paper or string
• Withstand strain upto 99 kg
• Instantaneous action
• High degree of proportionality to the muscle activity
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23. Features cont.....
• Silicone cosmetic glove : touch sensitive for touch
screen devices
• Grip chips : Bluetooth enabled devices that are stuck
to daily and mostly used objects eg. BT keyboard
• Triggers pre-programmed chip configuration when
detected by i-limb
• Apps : Biosim,
• My i-limb mobile apps – compatible
with android
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24. Features cont.....
Vari grip mode : variable digit by digit grip strength
Auto grasp mode : prevents objects from falling
Inactivity : automatically moves to standby resting
position
Feeling as part of body
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25. 23 Apr 2013
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28. Right candidate ?
• Amputation at the wrist or forearm
• Standard body-powered prosthetic devices are insufficient
to meet the functional needs
• Musculature has minimum microvolt threshold to allow
operation of a myoelectric prosthetic device
• No neuromuscular disease
• Good cognition
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29. Bionic fingers/i-limb digits
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Trans-metacarpal
amputations

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31. Positives
Simple to implement
Non-invasive
More range of motion
Individually moving fingers allow for better grip
Larger functional area- more ADL independence
More natural appearance
Dust resistant
Can reduce phantom pain
Psychological advantage
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32. Setbacks
Heavy- muscle fatigue and friction
Cost
Availability
Moisture- problem with electronic circuitry if
improper fabrication
Require prepositioning for some actions
Finger control coupled with open/close function,
so not completely independent
No sensory control to control grip strength
Pre-programmed grip patterns to learn
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33. Future promising areas
Challenge : Limited input to control vast outputs
Targeted Sensory Re-innervation (TSR)- sensory
feedback
Artificial muscles(Electroactive polymers)
Osteo-integration
Mechano-myographic (MMG) feedback: control of a
prosthetic device with cortical and peripheral nerves
Other Bionic Limbs
 -Shoulders, Wrists, Elbows
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34. Boston digital arm
Bebionic 3 (Terminator hand) : developed by RSL
Steeper
 Multi-articulating myo-electric hand
Michelangelo hand :
 Developed by Advanced Arm Dynamics & Otto Bock
 Features a thumb that electronically moves to different
positions for multiple grip functions
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36. Before your comments and questions......
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37. Cost of an i- limb hand ????
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38. Ans : $ 18,000 - $ 48,000 /-
= Rs 11,02,140 – 29,39,040 /-
( 1 $ = Rs 61.23) ≈ ( 27/09/2014)
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39. Thank you !!
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