Lower limb prosthesis

Over view of lower limb prosthesis

1. LOWER LIMB PROSTHESIS Dr Thileebphan

2. INTRODUCTION Prosthesis Device to replace part of the limb or missing limb Prosthetist Person skilled in prosthetics and its application Residual limb Part of the limb that remains after an amputation  Orthosis Externally applied mechanical devices to Support weakened injured, paralyzed, diseased part as supplementation.

3. TO THINK….. If lower limb amputation done in FOUR patient how many will die with in ONE MONTH?

4. IDEAL PROSTHESIS Provide Posture , Balance, Stability Provide Comfortable mobilization Performing desired activity Pleasing cosmetically Protect & accommodate residual limb

5. PRESCRIBING THE PROSTHESIS 1.Level of amputation , 2.State of residual limb, 3.Activity level K-rating scale US Department of Health and Human Services’ Centerfor Medicare and Medicaid Services. K-0 – Non- ambulator requires assist with transfers K-1 - Household ambulator K-2 – Limited community ambulation K-3 - Unlimited community ambulation K-4 - Exceeds basic use

6. LEVEL OF AMPUTATION IN LOWER LIMB

7. LOWER LIMB PROSTHESIS 1.Trans -femoral prosthesis 2.Trans-tibial prosthesis 3.Foot prosthesis

8. MAJOR COMPONENT OF THE LOWER LIMB PROSTHESIS 1. The control system 2. Suspension mechanism 3. Socket 4. Knee joint 5. Pylon 6. Terminal device

9. Suspension system

10. CONTROLLING SYSTEM Simple prosthesis - largely through gravity The most sophisticated (and expensive) prosthesis - myo electric Electrodes to sense muscular impulses in the residual limb

11. SUSPENSION Attaches the prosthesis to the residual limb. It actually- 1. Prevent pistoning . 2. Holding and prevent slippage during stance.

12. TO THINK….. What if not bother about pistoning of socket?

13. Types Straps & Belts- Selesian belt, Thigh corset – For AK Cuff – Supra- condylar cuff, Supra-patellar cuff – F or BK ( cautious with PVD patients .) 3. Suspension sleeve – Elastomer material rolling into stump and holding by negative pressure - For BK & AK 4. Suction System – Socket itself attaching to stump by negative pressure, not suitable in tibia 5. Shuttle lock system – More advanced - For BK & AK 6. Combined

14. Selesian Belt

15. Supra condylar cuff

16. Suspension Sleeve & Suction system ..\Downloads\Suction system.mp4

17. Shuttle lock system ..\Downloads\ suttle locksystem 3.mp4

18. SOCKET The connection between the residual limb and the prosthesis ; It needs to 1. Accommodate & protect the residual limb. 2. Transmit the forces evenly through a greater surface area. 3. Decrease pressures to any constant area. 4. Not allow distal pooling of fluid within the residual limb.

19. Types Trans- Tibial Sockets – 1. PTB socket 2. Hydrostatic Trans-Femoral Sockets 1. Cylinder 2. Quadrilaeral 3. Ischial containment 4.Flexible socket Advancement and more comfortable

20. Patellar tendon bearing socket

21. Ischial containment trans femoral socket

22. Flexible trans femoral socket

23. KNEE In case of the trans femoral prosthesis –it is wanted. It is available Single axis Multiaxis

24. Types 1.Fixed cadence knee – Fixed resistance in the knee unit to control the pendulum action of the prosthesis. Rate of swing is set by the prosthetist . For K1 & K2 patients 2. Variable cadence knee – Accomodates user’s walking speed and adopt the gait. 1. Hydraulics or pneumatic – for control and set rate range . For K3 2. Intelligent knee – Combining the micro processor with above mechanism. For K4

25. TO THINK….. Roughly how much it will cost to purchase a intelligent knee?

26. PYLON A simple tube or shell that attaches the socket to the terminal device . It evolved From simple static shells to dynamic devices that allow axial rotation and absorb , store, and release energy.

27. Types Exo skeleton Composed of a solid piece of wood or rigid polyurethane covered with plastic laminate and fashioned into the shape of a leg. Endo skeleton Internal metal frame with aesthetic soft covering. Made of - lightweight nylon, aluminum, or carbon/graphite. Completely interchangeable & prosthesis easily repairable.

28. TO THINK….. During prosthetic prescription , does weight of prosthesis matter?

29. TERMINAL DEVICE Typically a foot and ankle. It is expected to Give push off Ankle function mainly dorsi flexion Shock absorbtion .

30. Types Non dynamic response foot – More conventional Great ground reaction force SACH(Solid ankle/cushioned heel ) For K1 & K2 Dynamic response foot More advanced Push off, ankle function and shock absorption . For K3 & K4

31. SACH Foot

32. Dynamic response foot

33. COMPLICATIONS DUE TO PROSTHESIS Choke syndrome Dermatologic problems Painful residual limb 4. Ineffective suspension system 5. Poor socket fit 6. Stump volume changes

34. REFERENCE 1. Componentry for Lower Extremity Prostheses Friel , Karen PT, DHS JAAOS - Journal of the American Academy of Orthopaedic Surgeons:  September 2005 - Volume 13 - Issue 5 - p 326–335 Articles 2. AAOS 2 nd edition.