PROSTHETICS AND ORTHOTICS
INTRODUCTION
PROSTHESIS: IT’S A DEVICE DESIGNED TO REPLACE A MISSING PART OF THE BODY OR TO MAKE A PART OF THE BODY WORK BETTER.
ORTHOSES: IT’S A DEVICE THAT SUPPORTS OR CORRECTS THE FUNCTION OF A LIMB OR THE TORSO
• SPECIFICATIONS FOR IDEAL PROSTHESIS/ORTHOTICS:
1. FUNCTION:a)MEET USERS NEEDb)SIMPLEc) EASILY LEARNEDd)DEPENDABLE2.COMFORT:a)FITS WELLb)EASY TO PUT ON AND TAKE OFFc) LIGHT WEIGHTd)ADJUSTABLE.
3.COSMESIS:LOOKS ,SMELLS,SOUNDS NORMALEASILY CLEANEDSTAIN RESISTANT
4.FABRICATION:FAST,MODULARREADILY & WIDELY AVAILABLE
5.ECONOMICS:AFFORDABLE COST EFFECTIVE.
MATERIAL USED:1)METALS:STEEL,ALUMINIUM,ALLOYS OF
TITANIUM2)PLASTICS:THERMOPLASTICS &
THERMOSETTING PLASTICS3)WOOD4)LEATHER5)RUBBER6)FABRIC
1)METALS:
A)STEEL:USED IN – PROSTHETIC & ORTHOTIC JOINTS,METAL BANDS,CUFFS,SPRINGS,BEARINGS.
B)ALUMINIUM: UPPER
EXTERIMITIES,PEDIATRIC,WHERE WT IS A MAJOR CONCERN
C)TITANIUM:HIGH COST
2)PLASTICS: CAN BE MADE INTO
COMPLEX ANATOMIC SHAPESA)THERMOPLASTICS: LOW TEMPERATURE
THERMOPLASTICS:UPPER LIMB ORTHOTICS & TEMPORARY USE(# BRACE).HIGH TEMPERATURE PLASTICS
B)THERMOSETTING:
WOOD:MAPLE & HICKORY-PROSTHETIC FOOT ,BASEWOOD,WILLOW,LINDEN FOR PROSTHETIC KNEES & SHINS
LEATHER:VEG.TANNED COWHIDE- SUSPENSION
STAPS,WAIST BELTS,SOCKET LINERS ,COVERINGS FOR ORTHOSES & PROSTHESES
FABRIC:WOOL, COTTON,SILK(NAT),SYNTHETIC- NYLON,OLEFIN,POLYESTER,RAYON,VINYL
PROSTHESIS:USED FOR-WAIST BELTS,STRAPS,HARNESS,SOCKS WHICH KEEP SKIN DRY,CUSHIONING
ORTOSES:CORSETS;BELTS,STOCKINGS
RUBBER: SEALS IN HYDRAULIC & PNEUMATIC MECHANISMS –HEELS,BUMPERS IN PROSTHETIC FEET & SPECIAL FOOTWEAR
IMPORTANT CHARACTERISTICS OF P & O MATERIALS :
1)STRENGHT2)DURABILITY3)DENSITY4)CORROSION RESISTANCE5)EASE OF FABRICATION6)COST & AVAILABILITY
PROSTHETICS
• 1. UPPER LIMB: THE SHOULDER PROVIDES THE
CENTRE OF RADIUS OF THE FUNCTIONAL SPHERE OF UPPER LIMB,THE ELBOW ACTS A CALIPER TO POSITION THE HAND.
• MULTIPLE JOINT-SEGMENT ACTIVITIES ARE USUALLY DONE SIMULTANEOSLY,WHERE AS UPPER LIMB PROSTHESES PERFORM THESE TASKS SEQUENTIALLY,THUS LIMB SALVAGING IS MORE CRITICAL FOR UPPERLIMB.
• AFTER AMPUTATION PROSTHETIC FITTING SHOULD BE DONE AS SOON AS POSSIBLE,EVEN BEFORE COMPLETE WOUND HEALING HAS OCCURRED.
• MYOELECTRIC PROSTHESES PROVIDE GOOD COSMESIS & ARE USED FOR SEDENTARY WORK.
• BODYPOWERED PROSTHESIS ARE USED FOR HEAVY LABOUR.
WHEN RESIDUAL FOREARM IS SO SHORT: SUPRACONDYLAR SUSPENSION (MUNSTER SOCKET) AND STEP UP HINGES CAN BE USED TO AUGMENT FUNCTION.
THE BEST FUNCTION WITH LEAST WEIGHT AT LOWEST COST IS PROVIDED BY HYBRID PROSTHETIC SYSTEMS –MYOELECTRIC+BODY POWERED+BODY DRIVEN.
WHEN THE LEVER ARM CAPACITY OF THE PROXIMAL TRANSHUMERAL OR SHOULDER DISARTICULATION AMPUTATIONS,LTD FUNCTION IS ACHIEVED – MANUAL UNIVERSAL SHOULDER JOINT POSITIONED BY THE OPPOSITE HAND,COMBINED WITH LIGHT WEIGHT HYBRID PROSTHETIC COMPONENTS.
LOWER LIMB PROSTHETICS:1.PROSTHETIC KNEES: USED IN
TRANSFEMORAL & KNEE DISARTICULATION PROSTHESES AND CHOSEN BASED ON PATIENT NEEDS,THEY PROVIDE CONTROLLED KNEE MOTION.
ALIGNMENT STABILITY(POSITION OF PR. KNEE IN RELATION TO PATIENTS LINE OF WEIGHT BEARING:
POSTERIOR:STANCE CONTROL ;MAKES FLEXION DIFFICULT.
ANTERIOR:FLEXION IS EASY,CONTROL DIFFICULT
SO, ONLY THE POLYCENTRIC KNEE TAKES ADVANTAGE- HAS A VARIABLE CENTRE OF ROTATION.
SIX TYPES:B
1.POLYCENTRIC(4- BAR LINKAGE)2.STANCE PHASE CONTROL3.FLUID CONTROL4.CONSTANT FRICTION5.MANUAL LOCKING KNEE6.VARIABLE FRICTION
1.POLYCENTRIC KNEE:
HAS A MOVING INSTANT CENTRE OF ROTATION,ITS RECOMMENDED FOR :
a)PATIENTS WITH TRANSFEMORAL AMPUTATIONS
b)PATIENTS WITH KNEE DISARTICULATIONSc)B/L AMPUTEES
2.STANCE PHASE CONTROL(SAFE/WT.ACTIVATED):
FUNCTIONS LIKE A CONSTANT –FRICTION KNEE DURING THE SWING PHASE ,FREEZES WHEN WT. IS APPLIED TO THE LIMB.ITS USED IN OLD PATIENTS,HIGH LEVEL AMPUTEES / USE ON UNEVEN TERRAIN
3.FLUID CONTROL KNEE:1. ALLOWS
ADJUSTEMENT OF CADENCE RESPONSE BY CHANGING RESISTANCE TO KNEE FLEXION – PISTON MECHANISM.IT PREVENTS EXCESSIVE FLEXION & IS EXTENDED EARLIER IN THE GAIT CYCLE – FLUID GATE
USED-ACTIVE PATIENTS ;GREATER UTILITY & VARIABILITY @ EXPENSE OF MORE WEIGHT.
4.CONSTANT FRICTION KNEE:
DAMPEN KNEE SWING VIA SCREW/RUBBER PAD THAT APPLIES FRICTION TO THE KNEE BOLT.
USED ON UNEVEN TERRAINMOST COMMON KNEE USED IN
CHILDHOOD PROSTHETICSDISADVANTAGE: ALLOWS ONLY SINGLE –
SPEED WALKING & RELIES ON ALIGNMENT FOR STANCE PHASE
5.VARIABLE FRICTION KNEE(CADENCE CONTROL):
ALLOWS RESISTANCE TO KNEE FLEXION TO INCREASE – KNEE EXTENDS BY EMPLOYING A NUMBER OF STAGGERED FRICTION PADS.
ALLOWS WALKING @ DIFFERENT SPEEDS NOT DURABLE,NOT AVAILABLE IN
ENDOSKELETON
6.MANUAL LOCKING KNEE:
CONSISTS OF CFK HINGE WITH A POSITIVE LOCK IN EXTENSION THAT CAN BE UNLOCKED TO ALLOW FUNCTION SIMILAR TO CFK
LTD INDICATIONS:WEAK UNSTABLE PATIENTS,BEGINNERS,BLIND AMPUTEES
PROSTHETIC SHANKS: STRUCTURAL LINK B/W TWO
PROSTHETIC COMPONENTS 2 VARITIES –a) endoskeletal b)exoskeletal
SUSPENSION SYSTEMS: MAINLY VIA SOCKET
DESIGN & SUSPENSION SLEEVES SOCKETS ARE DESIGNED :FUNCTON
CONTROL& EVEN- PRESS. DISTRIBUTION ON AMP. STUMP
A)TRANSTIBIAL SUSPENSION: GEL- LINER SUSPENSION SYSTEMS WITH LOCKING
PIN IS PREFERED.ALLOWS UNRESTICTED KNEE FLEXION
PROSTHETIC SLEEVES SUPRACONDYLAR SUSPENSION(RESID.LIMB<5 CM) SUPRACONDYLAR-SUPRAPATELLAR SUSPENSION
B)TRANSFEMORAL SUSPENSION: VACCUUM SUSPENSION IS
COMMONLY USED.STABLE BODY WT. IS NEEDED
C)TRANSFEMORAL SOCKETS: QUADILATERAL SOCKETS ARE
USED,DIFFICULT TO KEEP FEMUR IN ADDUCTION
ISCHIAL CONTAINMENT SOCKETS – COMFORTABLE
ALLOWS 10°ADDUCTION & 5°FLEXION
D)TRANSTIBIAL SOCKETS:
PATELLAR TENDON BEARING LOADS ALL AREAS OF RESIDUAL LIMB THAT ARE WT. TOLERANT(PAT.TENDON,MEDIAL TIB, FLARE,GASTROCNEMIUS,FIB SHAFT)
PROSTHETIC FEET:CLASSIFIED INTO FIVE CLASSES:1)SINGLE AXIS FOOT2)SACH FOOT3)SAFE FOOT4)MULTIP AXIAL FOOT5)DYNAMIC RESPONSE FEET
1)SINGLE AXIS FOOT:BASED ON ANKLE HINGE-DOSIFLEXION &
PLANTARFLEXIONLTS:POOR DURABILITY & COSMESIS,NO
LATERAL MOVEMENT
2)SACHS FOOT(SOLID ANKLE CUSHIONED HEEL):
• ADVANTAGES:a)MODERATE WEIGHTb)DURABILITY
C)NO MOVING COMPONENTd)MIN MAINTAINENCEe)GOOD SHOCK ABSORPTIONDISAVANTAGES:a)LTD PLANTAR FLEXION & DORSIFLEXION
ADJUSTABILITYb) HEEL CUSHION DETERIORATES
OVERTIMEC) MAY LOOSE ELASTICITYd)POOR SHOCK ABSORPTION FOR HIGH –
OUTPUT ACTIVITIES
3)SAFE FOOT(STATIONARY ATTACHMENT FLEXIBLE ENDOSKELETAL):
PERMITS TRIPLANAR MOVT.& EASY ROLL-OVERLIGHT WEIGHT-OLDER PEOPLE
4)MULTIAXIAL FOOT:PROVIDE MORE ANKLE MOTIONENDOSKELETAL & EXOSKELETAL PROSTHESESADVANTAGES:
A)ALLOWS MOTION IN ALL PLANES
B)REDUCES TORQUE ON RESIDUAL LIMBC)ADJUSTABILITY
DISADVANTAGES:A)INCREASED WTB)INCREASED MAINTAINENCEC)DECREASED COSMESISLESS STABILTY ON SMOOTH SURFACES
5)FLEXIBLE KEEL DYNAMIC – RESPONSE FEET:
INDICATED FOR PEOPLE – GAIT PATTERNS GENERATE ENOUGH ENERGY
ELASTIC KEEL STRUCTURES- ABSORB ENERGY DURING MIDSTANCE & TERMINAL STANCE,RELEASE IT DURING PRESWING & INITIAL SWING
DURABILITY OF MATERIAL IS NOT TESTED
ORTHOSES: STATIC/DYNAMIC/COMBINED NAMED ACCORDING TO THE JOINTS
THEY CONTROL & METHODS THE FOLLOWING ARE USED:A)SHOES-DIABETIC SHOES:XTRA
DEPTH,SACH HEELS:PARALYTIC FOOT,ROCKER SOLE:METATARSALGIA,HALLUX RIGIDUS & FOREFOOT PROBLEMS
B)FOOT ORTHOSES: THEY ARE USED TO:1)ALIGN & SUPPORT2)PREVENT,CORRECT/ACCOMODATED
DEFORMITIES3)IMPROVE FOOT FUNCTION 3 TYPES:RIGID,SOFT,SEMIRIGID RIGID:FLEXIBLE DEFORMITIES SOFT:FIXED DEFORMITIES
C)A.F.O:MOST COMMONLY USED TO CTRL ANKLE
JOINTGOALS:ABSORPTION OF GROUND REACTION
FORCES,PROTECTION OF FUSION SITES,PROTECTION OF MIDFOOT
D)K.A.F.O:EXTENDS :UPPER THIGH – FOOTCONTROL UNSTABLE /PARALYSED KNEE JOINTPROVIDES MEDIOLATERAL STABILITY
E)H.K.A.F.O:PROVIDES HIP & PELVIC STABILITYRARELY USEDUSED IN CHILDREN WITH UPPER LUMBAR
MYELOMENINGOCELE
F)ELBOW ORTHOSES:HINGE ELBOW ORTHOSES-LIGAMENT
INSTABILITIESDYNAMIC SPRING LOADED ORTHOSES-
FLEXION/EXTENSION CONTRACTURE
G)W.H.O:USED FOR POSTOP CARE AFTER
INJURY/RECONSTRUCTIVE SURGERYSTATIC/DYNAMICOPPONENS SPLINT-PREPOSITIONING
THUMBLOWER CERVICAL QUADRIPLEGICSLT.FACTORS:WT & CUMBERSOMNESS
H)FRACTURE BRACES:TREATMENT OF ISOLATED # TIBIA &
FIBULAPRE-FABRICATED:ANKLE#,ANKLE
SPRAIN,HAND INJURIES
I)PEDIATRIC ORTHOSES: THE PAVLIK HARNESS – TREATMENT OF
DEVELOPMENTAL DISLOCATION OF HIPUSED IN PERTHES DISEASE
J)SPINE:1)CERVICAL SPINE:NUMEROUS ORTHOSES ARE USED TO
IMMOBILISE SPINECOLLARS,HALO VEST2)THORACOLUMBAR:STABILISATION OF MECHANICAL
BACKPAIN –INCREASING BODY CAVITY PRESSURE