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