Floor reaction orthosis

Dr Jipin GopiJR

Dept of Orthopaedics

Objectives

• Definition • Principle• Indications• Advantages, • Disadvantages• Limitations

Definition • An externally applied device used to– modify the structural– or functional– characteristics of the neuromusculo-skeletal system.

• An apparatus used to – support, align, prevent, or– correct deformities or – to improve the function of – movable parts of the body

Floor Reaction Orthosis

• Custom Made Orthosis

• Made up of 1. light weight Poly Propylene or 2. Carbon fibre reinforced PolyPropylene

• Used in Quadriceps paralysis 

Synonyms

1. Floor reaction orthosis ( FRO) 2. Floor reaction ankle foot orthosis (FR AFO)

3. Ground reaction orthosis 4. Ground reaction force ankle foot orthosis

(GRF AFO)

Components

1. Full toe base (foot) plate in equinus with – solid ankle

2. Uprights

3. Anterior/Pre tibial shell / knee piece

• Combination of the three components allow the – plantarflexion-knee extension couple (PF/KE) to – occur, causing a – knee-extension moment —

Designs

• One piece: – encloses the back of the lower calf, – the shin, and – bottom of the foot

Design

• Two piece: – same as the one piece but – has a removable anterior (front) panel

• Rear-opening: – encloses the front of the leg and – top of the foot. – May be articulated

• SM FRO

Quadriceps - Stance

• Early stance • Guides knee into flexion by eccentric

contraction (controls unlocking of the knee)

• Buckling of knee• Quadriceps gait

• Patient with paralyzed quadriceps,

• stance phase causes initial contact at heel ....

• the weight line to pass posterior to the knee axis...

• knee buckling.

Principle

• Ankle held in slight equinus • (5-8deg) in the design

• The initial floor contact occurs at the forefoot rather than heel 

• The axis of the weight bearing from COG of body to – the floor contact point will pass – in front of knee joint

• During mid stance phase ,– the body weight brings the heel

downwards, – there is an extension moment of

the prepatellar band– pushing the knee backwards, – prevent buckling

PRINCIPLE

• Newtons third law

• Here wt of the the body – over the orthosis and – over the ground is action

• Foot & orthosis absorb ground reaction forces which– enter the body and – keep the foot & knee straight.

Indications

1. Post Polio residual paralysis2. Spinal cord injury 3. Meningomyelocele 4. Cerebral Palsy

• Quadriceps weakness

Poliomyelitis

• Common causes of disability in India

• Quadriceps is commonly affected

• Walks with "hand to knee" gait

Wearing schedule• 1st day: – wear for one hour, – check skin

• 2nd day: – wear two hours, – check skin

• 3rd day onwards: – increase by one hour daily.

• If red marks don’t disappear by 30 mts, contact orthotist.

Weak Quadriceps

• KAFO with locked knee and – limited motion ankle joint

• Walk with rigid knee and – unphysiologic, energy inefficient gait

Advantages

• Light Weight-300gms

• Swing Phase is not labored as with a KAFO with locked knee

• Two weeks training, easy to use, less complicated

Advantages

• FRO works as a KAFO without a – mechanical knee joint

• Patient can utilize his anatomical knee joint without buckling

• Cosmeticaly acceptible-– can be worn under Shoe Compliance

Disadvantages

• It must be correct fitting, – getting in close contact with the skin and bony

prominences, – Skin problems

• difficulty in making - Custom Made Orthosis

Limitations

• Hip and knee FFD > 10 deg – correct fixed deformities prior to bracing for – the coupling principle to be effective.

• Quadriceps power > 2+/3-

• Flail knee or ankle

• Angular deformities – foot, ankle, tibia, trunk imbalance

Conclusion

• Orthosis for quadriceps weakness

• “Plantar flexion knee extension couple" principle

• PPRP limb is commonest indication

• SM FRO is the commonly used

• Flexion contractures / flail joints are contraindication

JAIPUR FOOT

INTRODUCTION

• The JAIPUR FOOT is an original research product of Jaipur INDIA

• The foot was developed in response to specific socio cultural needs of Indian Amputees ‐– (of squatting, – cross-legged sitting and – barefoot walking)

EVOLUTION

• The development of the Jaipur prosthetic foot in• the early 1970s

• JAIPUR centre started providing• conventional lower limb prostheses.

• Rejection rates HIGH ‐

• ANALYSIS OF REJECTION • The reasons were not technical OR

biomechanical

• BUT• Socio cultural ‐

• The team at Jaipur centre realized that besides

• functional aspects, • socio economic and cultural ‐

demands of amputees needed to be addressed.

CONCEPT & DESIGN

• Look like Human foot • Permit squatting • Adapt to uneven terrain • Should be waterproof

• Permit barefoot walking• Permit use within footwear • Should be affordable • Should be made of locally available materials

• Professor P. K. Sethi’s first efforts were to modify the SACH foot– Its solid wooden keel did not allow any movement – therefore a wedge was removed in order to allow

dorsiflexion

• This produced limited movement and – resulted in the removal of – increasingly larger wedges until almost– nothing was left of the proximal section of the

keel.

• At this stage he abandoned the SACH– foot and introduced a completely new design

• This prosthesis, which he named the ‘Jaipur• Foot’, consisted of three separate blocks– One of micro-cellular rubber for the hind foot – other two of laminated wood for – the ankle and forefoot,

• wrapped by an inner layer of tyre cord rubber• and an outer layer of skin-coloured soft rubber,• with tough rubber for the sole

• The foot was then vulcanised in an • aluminium die to look life-like.

• The forefoot wooden block was later• replaced with a – rubber block, similar to that of the hindfoot in order

to – provide pronation and supination, and – to allow stability on uneven ground

• The foot was attached to an– aluminium socket covered with stockinette,– glued, water-proofed and

• individually painted in the appropriate skin colour

• The large sponge rubber block at the hind– foot acted as a universal joint, capable of providing– multidirectional movements including– dorsi- and plantar flexion, inversion, eversion,– adduction and abduction.

• The foot could rotate on the leg

• This allowed the amputee not– only to squat and sit cross-legged, but also to– walk comfortably on uneven terrain, since the– foot could adapt easily to the underlying surface

• It consists of three structural blocks simulating the anatomy of a normal foot 1. forefoot block 2. heel block 3. ankle block.

• The forefoot and heel blocks are made of – sponge rubber while

• the ankle block is made of – light wood.

• These three blocks along with the toes are • bound together by tyre cord and • encapsulated in skin colored cushion

compound.

• This structure is then vulcanized at • 120 ⁰ under 23 psi for 30 minutes.

RANGE OF MOTION • Dorsiflexion : 20º 35º‐• Heel compression : 0.8mm to 2.8 mm.• Pronation 26 º 29º‐• Supination : 15º 22º‐• Axial Internal Rotation : 10º 12º• Axial External Rotation : 4º 8º‐

Advantages • it does not require any shoe,

– i.e., amputees can walk barefoot.

• It is made of waterproof material enabling amputees to walk in wet and muddy fields.

• permits enough dorsiflexion and o– ther movements necessary to adapt itself while walking on

uneven surfaces.

• most cost-effective foot-pieces available in the world • it is light in weight

Acceptance in the developed world

• Unacceptable

• Craftsmanship & fitting – poor in 86%• patient acceptance –94%

• How illogical /contradictory !

• Research has been ongoing to improve on the design.

• Some aspects that still remain to be addressed are 1. Jaipur foot is not available in nternational standards 2. Jaipur foot is not compatible with designs of Western

limbs.

3. Jaipur foot is heavier than the set international 4. Standards.

5. Jaipur foot still does not come with quality assuranceassurance certification

Future course

• sizing the jaipur foot to meet international standards

• designing the jaipur foot to be compatible with the western prosthetic designs.

• material modifications to reduce weight and increase durability

• standardizing testing equipment for quality assurance