Bionic hand discussed in brief for ortho.pptx

Bionic hand discussed in brief for ortho

1. DR. T. JAWAHAR MCH HAND SURGERY PG Bionic Hand 1

2. History of Prosthetics Oldest known splint: 5 th 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 2

3. 1529, Ambroise Pare, French surgeon introduced amputation – 1 st 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 3

4. History of Myoelectric prosthesis Myoelectric control (1945) : 1 st 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 :1 st 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 4

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 5 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

7. Prosthetic options Passive prosthesis Body-powered prosthesis Electrically powered prosthesis Hybrid prosthesis Activity-specific prosthesis 7

8. Passive prosthesis Passive : No moving part/function Cosmesis 8

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 9

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 10

11. Hybrid Prosthesis Combination of body and electrically powered types At or above elbow amputations : Body-powered elbow and electrical terminal device and wrist 11

12. Activity specific terminal devices 12

13. Terminal devices : Passive : No moving part/function Cosmesis Passive hand, Mitts Prehensile : Hooks – Voluntary opening/closing Hands - Voluntary opening/closing 13

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 14

15. Hand 15

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 16

17. Processor and electrodes Battery 17

18. Basic descriptions 18

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 19

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. 20 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 commands 21

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 22

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 23

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 24

25. 23 Apr 2013 27/9/2014; 2 pm 25

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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 28

29. Bionic fingers/ i -limb digits 29 Trans-metacarpal amputations

30. Advantages 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 30

31. Disadvantages 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 31

32. 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 32

33. 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 33

34. Cost of an i- limb hand ???? 34

35. $ 18,000 - $ 48,000 /- = Rs 11,02,140 – 29,39,040 /- ( 1 $ = Rs 61.23) ≈ ( 27/09/2014) 35

36. Thank you !! 27/9/2014; 2 pm 36