Prosthetic Feet

 

Prosthetic Feet Classification Classifica tion & Overview Overview

M. Jason Highsmith, PT, DPT, CP, FAAOP University of South Florida College of Medicine School of Physical Therapy & Rehabilitation Sciences “Demonstration Project on Prosthetics & Orthotics”

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Objectives

Upon of this unit, the student will: • completion Demonstrate understanding of Medicare’s Functional Modifier classification system •

 App ly K s cores to p atient scenar ios

•

Recall the six categories of prosthetic feet

•

Be able to describe popular examples of prosthetic feet in a given foot category

•

Recall benefits and drawbacks associated with prosthetic feet from the six categories

•

Be able to select an appropriate prosthetic foot based on a case scenario

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Medicare Functional Modifiers

The “K” Scale Scale:: K Level

Functional Description

Prosthetic Feet

Prosthetic Knees

K0

Non-ambulatory. Not a prosthetic candidate.

None

None

K1

Limited and unlimited household ambulation. Level surfaces. Fixed cadence. Transfers and therapeutic use.

Basic Feet: External Keel, SACH, Single Axis

Basic knees

K2

Limited community ambulation. Able to traverse low-level environmental barriers (curbs, ramps, stairs, uneven surfaces).

Multi-axial feet, Flexible Keel feet, Axial rotation (ankle) unit

K3

Community ambulation. Variable cadence gait (or potential). Most environmental barriers.

Dynamic response feet

Fluid & Pneumatic knees

K4

Children. Those with Bilateral involvement. Active adult.  Athletes. Exceeds basic use.

 Any

 Any

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Who are they? K1

K2

K4

K3

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Classes of Feet 1.

SACH SACH feet feet (solid (solid an ankle kle c cush ushion ioned ed hee heel) l)

2.

Si Sing ngle le Ax Axis is feet feet

3.

Mu Mult ltii-ax axia iall feet feet

4.

Dynami Dynamic c respons response/ e/ En Energy ergy storing storing ffeet eet

5.

Mul Multi-a ti-axia xiall + Dynam Dynamic ic respo response nse ffeet eet

6.

Adjust Adjustabl able eh heel eel hei height ght fee feett

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

SACH (solid ankle cushioned heel)

Smith-Global SACH Foot for K1 LevelNon-ambulators

Kingsley SACH Foot

Kingsley Continental SACH Foot (1” heel)

Kingsley Symes SACH Foot

Ohio Willow Wood SACH Foot w/ pyramid

Kingsley HI-Style SACH Foot (31/2” heel)

Ohio Willow Wood SACH Foot

Ohio Willow Wood P-Pod (pediatric) SACH Foot

Kingsley Wayfarer SACH Foot (flat w/ split toe)

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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SACH (solid (solid ankle cushioned h eel)

Benefits  – Several heel heights  – Several weight categories  – Several activity level categories

Kingsley SACH Foot Kingsley Juvenile SACH Foot

 – Several manufacturers  – Syme’s option  – Durable- low maintenance  – Good choice for pediatrics  – Easy to replace  – Endo or Exoskeletal

Kingsley Cowboy HiHeel SACH Foot (13/8” heel, smooth toes)

 – Inexpensive Option for all K levels

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

SACH (solid (solid ankle cushioned h eel)

Drawbacks

 – Not for use if active keel is needed  – Poor multi-axial abilities  – Poor choice if knee stability is questio onable nable  – Poor shock attenuation

Foot Bolt and SACH foot adapter. Also wo rks on Seattle Feet.

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Single Axis feet

Ohio Willow Wood Pyramid

Plantar Flexion Bumper 

Location of Dorsiflexion Bumper 

Sagittal Hinge Axis

Bolt(s) for Foot/Plate

Components of Single Axis foot Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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Single Axis Feet Benefits  – Adjusts joint angle to accommodate uneven terrain (sagittal (sagittal only)  – Plantar and Dorsiflexion bumpers are replaceable with more or less compliant bumpers  – Relatively inexpensive  – Indicated when knee stability is an issue issue (TTA or TFA)  – Option for all K levels

Drawbacks  – Increased maintenance associated with moving parts  – Difficulty cosmetically finis shing hing due to moving parts  – Contraindicated if knee is stable  – Contraindicated if multi-axial function function is needed  – Contraindicated if dynamic response is needed

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Multi-Axial Feet Feet  A foot or foot-ankle system that moves or articulates in more than one plane.  – Inversion,  – Eversion,  – Plantar Flexion  – Dorsi Flexion  – Transverse Rotation

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Multi-Axial Feet Feet Examples:  – Greissinger Plus™  from Otto Bock Health Care®   – Endolite™   Multiflex Foot & An Ankle kle®   – Ohio Willow Wood®  Earthwalk2™   ** the Multiflex and Earthwalk2 systems include separate separate ankle units

EndoliteMultiflexFoot EndoliteMultiflexFoot & Ankle

Earthwalk2 Foot/Ankle System

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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Multi-Axial Feet Feet Benefits  – For use with K2 ambulators & above  – Accommodates to uneven ground  – Variety Drawbacks  – Offers little energy for toe off   – Increased cost  – Increased maintenance  – Each has separate procedure for cosmetic finishing  – Accommodation period and training

 Award # H235J050020 Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award

Dynamic Response/Energy Storing Feet Feet Examples • Seattle Lite™  by Seattle Limb Systems®  • Pathfinder ™   ™   by Ohio Willow Wood®  •  Axtion™  by Otto Bock Healthcare ® 

 Axtio n from Ott o Bock Healthcar e Pathfinder from Ohio Willow Wood Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Dynamic Response/Energy Storing Feet Feet Benefits  – Returns stored energy, which aid ds s in propelling foot forward at toe off   – For active ambulators (K3 and above)  – Some designs offer limited multi-axial accommodation accommodation (not technically considered multi-axial)  – Variety

1D35 Dynamic Motion Foot from Otto Bock Healthcare Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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Dynamic Response/Energy Storing Feet Feet Drawbacks  – Typically expensive  – Varied cosmetic finishing procedures  – Moving parts may mean increased maintenance  – Accommodation period

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Multi-Axial + Dynamic Response Feet Feet • Combines Combines a aspects spects of both both features features • Closest Closest func functiona tionall repl replacemen acementt of anatomy anatomy • Represents Represents ““state state of the art” for pr prosthet osthetic ic fe feet et

 ADP2 (Advant age Dynamic Pylon ) from Otto Bock Healthcare Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Multi-Axial + Dynamic Response Feet Feet Examples:

Vari-Flex

®   Flex Feet®  Line • Ossur ®

 – Vari-Flex®   – Ceterus®   – Talux®   –  Axia™  

Ceterus

Talux

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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Multi-Axial + Dynamic Response Feet Feet Examples: • Springlite™  Line and Advantage Dynamic Pylon (DP) 2 by Otto Bock®  Healthcare  – LuXon™  Max Dynamic Pylon (DP)  – The Springlite™ II

 ADP2 (Advant age Dynamic Pylon ) from Otto Bock Healthcare

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Multi-Axial + Dynamic Response Feet Feet

Benefits

 – Variety  – Excellent functional options  – Solution for high-level patient/clients

Drawbacks  – Expensive  – Not for lower level ambulators  – Accommodation period

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

 Adj ust able Heel Heigh t Feet • May have preset preset or infini infinite te adjustabili adjustability ty within a given given ROM • ROM

≈

30 (or ˚

≈

2 inches of heel height)

• Typically Typically M Medial edial push button button rreleas elease e

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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 Adj ust able Heel Heigh t Feet Examples: ®   • Elation™   by Ossur ®

• Runway™   by Freedom Innovations® 

Elation by Ossur  Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

 Adj ust able Heel Heigh t Feet

Benefits

 – Adjusts heel height for different footwear   – Option for dynamic response or flexible ble keel

Runway by Freedom Innovations

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

 Adj ust able Heel Heigh t Feet Drawbacks  – Not eligible for Medicare reimbursement reimbursement  – Increased moving parts; Increased maintenance  – May require two different density foams to cosmetically cosmetically finish  – Can be heavier than other feet  – Expensive

Elation by Ossur  Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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 Add it io nal Co mp onen ts

• Rota Rotato tors rs

• Tors Torsion ion Adap Adapter ters s • Ankl Ankle e Un Unit its s

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Rotators •

All Allow ow Cros Cross s leg leg sitti sitting ng

•

Do onn nnii ng ng s hoe hoes s

•

Used typically typically wit with h trans-fe trans-femoral moral and more proximal proximal level level amputees

Rotation Adapter 4R57 from Otto Bock Healthcare

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Torsion adapters • • • • •

Used at any leve level, l, build height pe permitting rmitting when transverse forces forces require attenuation May be installed installed proximal proximal or distal distal to anatom anatomic ic or prosthe prosthetic tic knee Variet Variety y of man manufa ufactu cturer rers s Good for for sand sand and m mud ud (com (complian pliantt surfa surfaces) ces) Good to decrease interface interface to skin friction friction in aggressive aggressive ambulators

Torsion Adapters 4R85 & 86 from Otto Bock Healthcare

Delta Twist 4R120 from Otto Bock Healthcare

Total Shock from Ossur 

Dura shockTorsion  Adapters from Fi llauer 

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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 Ank le Uni ts • Add degrees degrees of freed freedom om to non-mu non-multiax ltiaxial ial feet • May be be for daily daily ambu ambulat lation ion • May be a applic pplication ation specific specific

 Arthr ogli de ankle fr om Seattle limb systems

Endolite Endolit e ankle units

Rampro Rampro ankle unit for swimming

Earthwalk2 foot/ankle system

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Other Classifications • Ve Verti rtica call S Sho hock ck • Fl Flex exib ible le Ke Keel el • Ultr Ultra a Lig Light ht • Heav Heavy y Du Duty ty

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Vertical Shock •

Compre Compressi ssive ve device device

•

Ideall Ideally y adj adjust usted ed to b be e equa equall height during quiet standing

•

May be integ integrat rated ed into into tthe he foot

•

May be extra extra comp compone onentr ntry y

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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Flexible Keel •

More More adv advanc anced ed th than an a SA SACH CH bu butt

•

Does not retur return n energy like a dy dynamic namic respons response e foot

•

Too much action action for K1 level ambulators ators but insuffici insufficient ent for K3 level ambulators

•

May or may not be mul multiaxi tiaxial; al; may iinclud nclude e an ankle

Endolite ankle units

Kingsley STEN foot

Ohio Willow Wood Earthwalk2

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Ultra Light Sufficient support for  – therapy,  – transfers and  – very limited ambulation • e.g. household ambulation

 – Minimal weight/mass The Dycor STM ((soft soft tissue management) foot is for K1&2 level level ambulators. The Dycor foot line has higher function feet and all are extremely light weight.

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Heavy Duty Required with high mass  – May be body mas mass s or   – Body mass plus external load  – e.g. lifting for occ occupational upational requirem requirement ent  – Most components cut off between 200 and 275lbs  – Above manufacturer’s recommended weig ght ht restrictions, custom feet may be available

Magnum foot and system from Ohio Willow Wood. Rated up to 350 lbs.

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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Running Feet • No Heel • Radica Radicall Alignmen Alignmentt and set up • Cann Cannot ot w wea earr a sh shoe oe  – Traction considerations

•

Versi Versions ons availab available le for d distan istance ce run running ning o orr spri sprinting nting

Otto Bock Sprinter 

Ossur Flex-Run

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Classification Proposed by  A. Bennett Wilson, Jr.20

 Artificial Feet Feet

 Articulating  Articulatin g

Non-Articulating Flexible Keel

Single Axis

MultiAxis

Rigid Keel SACH

Greissinger 

ModerateFlexibility Other 

Leaf Spring

Other 

Seattle

Flex Feet

Elastomer  SAFE Carbon Copy STEN Flex Walk

Bock-“Dynamic” Others Others

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

References 1. 2. 3. 4. 5. 6. 7. 8.

American American Academ Academy y of Or Orthoti thotists sts and Pro Prosthet sthetists. ists. Prost Prosthetic hetic Foot/ Foot/Ankle Ankle Mechanisms. Official Findings Findings of the Consensus Conference. J Prosthet Orthot(S) 17(4), Oct 2005. Nassan Nassan S. Th The e latest latest desig designs ns in prostheti prosthetic c feet. feet. Phys Phys M Med ed Re Rehabi habill Clin N Am. 2000 Aug;11(3):609-25. Culham Culham ET, Pe Peat at M, Newell E: Analysi Analysis of gait gait folllowing owing below-kn below-knee ee amputation: A comparison of the SACH and single axis foot. Physiother Can. 36:237-242,1984. Brouwer Brouwer BJ, All Allard ard P, L Labell abelle H: Running Running pa pattern tterns s of juv juvenile eniles s weari wearing ng SACH SACH and single axis foot components. Arch Phys Med Rehabil. 70:128-134,1989. Burgess Burgess EM, et al. al. The Seattle Seattle pr prosthe osthetic tic foot-A foot-A desig gn n for act active ive spo sports: rts: Preliminary studies. studies. J Prosthet Orthot 37:25-31, 1983. CzernieckiJM, CzernieckiJM, Gitter Gitter A. Impa Impact ct of en energy ergy s storin toring g pros prostheti thetic feet o on n belo below w knee amputation gait (abstract). Arch Phys Med Rehabil 71, 1990. Edelstein Edelstein JE. JE. Pros Prostheti thetic c feet state of the art. art. Phys Phys Ther 68:1874-8 68:1874-81, 1, 198 1988. 8. Macfarlan Macfarlane e PA, et al: Gait Gait comparis comparisons ons for b below elow knee knee ampu amputees tees us using ing a flex foot versus a conventional conventional prosthetic foot. J Prosthet Orthot 3:150-61, 1991.

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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References 9. 10. 11.

12. 13. 14. 15.

Wirta RW RW et al: Effect Effect on gai gaitt using variou various s prost prosthetic hetic ankle ankle fo foot ot dev devices ices.. J Rehabil Res Dev 28:13-24, 1991. DoaneN, Holt LE. A compariso comparison n of the SAC SACH H and sin single gle axis axis foot in tthe he gait of unilateral transtibial amputees. Prosth Orth Int 7:33-36, 1983. Lehmann Lehmann JF, Pric Price e R, Boswell-Bes Boswell-BessetteS setteS et al. Comp Comprehen rehensive sive an analys alysis is of dynamic elastic response feet: Seattle ankle/lite te foot versus SACH foot. Arch Phys Med Rehabil. 1993; 74:853-61. Macfarlane Macfaamputees rlane PA, using Nielsen Nielsen DH,foot Shurr Shur r DG, Meier K. Gait comparis comp arisons onsfoot. for below knee a flex versus a conventional prosthetic J Prosthet Orthot. 1991; 3(4):150-61. Skinner HB et al. Static load response of the heels of SACH fe feet. et. Orthope Orthopedics. dics. Feb 1985; 8(2):225-8. Torburn Torburn L, Perry Perry J, Ayaapa Ayaapa E, ShanfieldSL. ShanfieldSL. Below kn knee ee amp amputee utee g gait ait wi with th dynamic elastic response prosthetic prosthetic feet: A pilot study. J Rehab Res Dev. 1990; 27: 369-84. Wagner Wagner J, Supan Supan T, Sie Sienko nko S, Bart Barth h D. Mot Motion ion ana analysi lysis s of SACH vs vs Flex foot foot in moderately active transtibial transtibial amputees. Clin Prosth Orth. 1987; 11(1):55-62.

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

References 16. 17. 18. 19. 20. 21. 22. 23. 24.

May B. Amputatio Amputations ns and Prosthet Prosthetics. ics. A Case St Study udy Appr Approach.2nd oach.2nd ed. F.A. Davis. ©2002. Seymour Seymour R. Prosth Prosthetics etics and Orthoti Orthotic cs. s. Lower Lim Limb b and Spinal. Spinal. Lippincott ncott Williams and Wilkins. ©2002. ISBN 0-7817-2854-1 ShurrDG, Michael Michael JW. Prostheti Prosthetics cs and O Orthot rthotics. ics. 2n 2nd d ed. P Pearso earson n Education, Inc. ©2002. ISBN 0-8385-8133-1 Lusa Lusardi rdi M & Nielsen Nielsen C. O Orthot rthotics ics an and d Pros Prostheti thetics c s in Rehabilitation. Butterworth-Heinemann. ©2002. ISBN: 0-7506-9807-1. Prosthetics-Orthotics Prosthetics-Orthotics Center, Northwestern University Medical School. Course Manual for Prosthetics 621: Transtibial Prosthetics for Prosthetists. Chicago, IL. IL. 09/2003 Wilson Wilson AB. A Primer on Limb Limb Prosth Prosthetic etics. s. Charles Charles C Thomas Pu Publis blisher her LTD. ©1998. HCFA Common Common Pro Procedu cedure re Coding Coding System System HCPCS 2001. 2001. Washin Washington gton (DC (DC): ): US Government Printing Office; 2001. ch 5.3. Ossu Ossurr Prosthetic Prosthetics s Product Product Cata Catalog log 20 2005. 05. Ossur hf. Otto Bock Bock Health Care. Orthotic & Prosthetic U.S. and Canada 2 2003 003 Catalo Catalog. g. © Otto Bock 2003.

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

References 25.

www.ossur.com

26.

www.ottobockus.com

27.

http://www.freedom-innovations.com/

28.

http://www.endolite.com/

29.

http://www.rampro.net/

30.

http://www.seattlesystems.com/

31.

http://www.college-park.com/

32.

http://www.smith-global.com/pdfs/Feet2005.pdf 

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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Contributions & Acknowledgements The University University of South Florida would like to thank the following persons and agencies for making this work possible: Jason T. Kahle, CPO Director of Lower Extremity Prosthetics Westcoast Brace & Limb Westcoast Brace & Limb of Tampa, FL Otto Bock Health Care Ossur Industries Seattle Limb Systems Kingsley Manufacturing EndoliteCorporation EndoliteCorpora tion Rampro Dycor 

 Award # H235J050020 Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award

For further about the content of the module, contact

University of South Florida [email protected] (813)974-8870 Fax: (813)974-8915

Westcoast Brace & Limb Westcoast www.wcbl.com (813)985-5000 Fax: (813)985-4499

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

Funded by the Department of Education, Rehabilitation Services Administration  Award# H235J05002 H235J050020 0 “Demonstration Project on Prosthetics and Orthotics”

University of South Florida College of Medicine: School of Physical Therapy & Rehabilitation Sciences College of Engineering: Mechanical Engineering Department M. Jason Highsmith, PT, DPT, CP, FAAOP William S. Quillen, PT, PhD, SCS, FACSM Rajiv Dubey, PhD

Funded by: U.S. Department of Education, Rehabilitation Services Administration Administration Award  Award # H235J050020

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