CA2061814A1

CA2061814A1 - Split foot prosthesis

Info

Publication number: CA2061814A1
Application number: CA002061814A
Authority: CA
Inventors: Van L. Phillips
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-02-28
Filing date: 1992-02-25
Publication date: 1992-08-29
Also published as: SE9200573D0; AU1126692A; US5181933A; US5776205A; GB9203973D0; ITMI920434A1; SE9200573L; FI920892A; ITMI920434A0; FR2673371A1; IT1254232B; NZ241792A; US5514185A; FI920892A0; GB2253148A; DE4205899A1; JPH0576557A

Abstract

Abstract of the Disclosure:
A prosthetic foot is characterized by an attach-ment section and plurality of curvilinear foot portions extending downwardly from the attachment section to contact a supporting surface. The portions are capable of movement independent from one another. Preferably, the plurality of foot portions is fabricated by dividing a forefoot portion and a heel portion demountably attached thereto. Such divi-sion may be achieved by the provision of a slot in said forefoot and heel portions. A strap or similar expedient is provided to limit the movement of the foot portions relative to each other.

Description

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aQkqr-o-~d~of he~ v~n~io~.
This in~n~ion rel~t~ ~o oot prs:~s~he~e~ ill gen-era~, and ~pecifiGal~y to a spl~t pro~the~c oot which incorporates a plu~al~tY of &ur~ near ~c~ot portio~s wh~ ch cooperate wi~h one ano~er ~0 pro~ria~ ~he wea~ wi~h per-form~n~e c~aar7.ctaristi~:s not a~rai~able ~ m pr~or art prc)s-t:hese~c A nu~er o ~ros'chetic ~evice~ ave a~tempted t~
1~ provide ~rlergy-storinS~ and -relea~ing ~uD~tions t:c~ si~nulate la~on on a na~ural li~. For ~xampl~ ee ~n~r ~.S. Let-t~r# Patent ~o. 4,547,91~ ~or ~y in~ention relatln~ to a "Compo~;~te Prosth~tic Foot and ~n~ and Vnited Sta~
~er Patent No, 4,8~2,3~3 ~or n~ in~ention relatirlg ~o a ~5 "~odular Compo~;~te ~>xosthetic Foo~ an~ n. Al~o~ my pend-ing applica~i~n~ Se~al No~ 07f337,374, 07~85,g20 and 07~93,8a4 d~sc~ e pros~eSi~: c~ devic~s ~i~h ~imila~r pref~rred mate:rial~ and meth~ f manufactura, ~nd with l:orresponding ~nefit ther~fro}~.
-~a~:h o~ ~y aora~nt~on~d imQn~ion~ 1~ c!harac:t~2r-ized ~y llghtwe~ght, ~longate~ s~rua~ures ~ncorporating polymer ~mpre~n~tion o~ supe~posQd r~inPorc~g lamina~

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main~ained ~n the desired con~i~uration. Such aonf~gura~
tions and construCtion~ pr~vi~e t~e d~irabl~ charac'c~r~-tics of stren~th 2md ~lexiblli~y in the pro~thetic me~ber, and achiev~ a simulation of the pe~fc~rmance of nat~r~ fe~t wh~h had previs~ly nct been attainable. Stlch pro~ ses may be prc~rided in me:~dular ~ em}: 1ies, wh~reby the particu-lar per~Eormanc:e cha~ac~ri~ti~s of a giv~n proæ~he~i~ may be ada~od an~ reaaily ad~ugte~ tc~ ~eet ~e need~ arld act~vitSr le~el of th~ individual patient.
Other pro~ foot dev~c~ include U.~. Pa'c.
No. 3,335,428 to G~do~, whi~ ~temp~c~ to duplicate the skel~tal and ~kin ~ ture of ~ na~ural h~nan ~ocst, U . 8 .
- Pat. No. 2, 075t 5~3 ~ an~e, whic~ ~nt:orporat:~; a rubber fe~ nount~a in operat~ve relat~v~ip wi~h ~ r~ etallic c:or~, a3~d U.5. P~'c. No. 4~45,50g to Pos~gi, ~hi~h tQache!s a pros~etic: ~o~ ~n¢orpora~ing a monoli~hic X~el or b~aam o~
r~lat~v~ly ~aE:s~ve p~oportion. ~r~ten~ed to r~ac:t ~o t~ load o an ~putee~s ~ody d~ring w~lking, runn~ng, jumping; ~nd t~e li3ee and to r~ale;!~e the r~sul~ant 2:tor~ ~ner~y to cr~
2 O ate f oo~ t ~nd thru~:t com~ple;nentlng ~e a~n~u~ee i ~ na~ural ~t~ide .
Althc~u~ ~s~eral of t~ a~rem~n~ aed pro~ ses a~a~e pr~vi~ed ~lex:u~e ln a for~-~n~-a~ dlrec:t~on~ ~3uc:h pr~or ar~ de~ are rela~lv~ly ~ and un~e~pon~l~e ~ith .

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resp~ct to to~s~onal loadin~ which ~ght re~ul~ ro~ leaning to one ~ide or from ambu~ atlon in a directi~rl ~th6~r than strai~t ahead~ In fac:t, such prog~he~e~ pro~ide a cont~s-tent erle~gy response ~ loading at any ~iv~n fo~-and-a~'c S lo~at~ on on the pro~hesi#, regardless o~ wh~the~ the load-in~ o~curs a~ one ed~e of the prc)æthesi3: or ~t th~a center thereof .

ObieG~ and A~v~cle~:_Q th~ ~v~ntiQn:
It iæ r ~he~e~ore, ~n o~ ect o~ ~y inven~cion to pr~d~ a E~rosthet~s: ~oot w~ich E~ro~ es a ~ra~ir~g ~ner~y-absorbing and energy- toring performance dependent pon the lateral locatlon o ~he oontact b~t~een ~he foot and an und~rlyinçl ~uppo~ng sur~ace, ~s well a~; 'che angle o impact ~2~ere~e~r~en. In partlcular, t~e pro~the~:is; o~ my ~$ in~erltion inacs~orats!s a plurality o~ ~oot porti~n~ capable c~ m~v~ment independ~ntl~ rom on~ ~n~'cher.
I~ a pxef~rred ~ odi~Q~nt, a~ described bel~w, ~he foot portion~ are ~ rica~ed by pro~ ding a slot ~hrc~ug~
virtually ~he ~ntire prosth~ , e~ec~ ly aiv~ing i~
2 0 iNto two in~pendent pros~hese~ 3n ~ot:h o th~
pendent ~o~rtion~ are ~intil~rly loa~ed and stre~d, ~ch a~
dur~rag s~raigh~-aheaa walk~n~, ~h~ por~ions Goope~ nd ac~ in unison to acsh~e~e a perform~nc~ ~mll~r to a ~o~t with no di~ n ther~in. ~hen the pxoE:thesi~: o~ ~y lnYqn tion unde~goe~ lateral l~a~lln~r howe~r, t~e ~rari~ por-tions ~nay act indepen~ently from one ano~her an~l thore~y prc~Yide perfo~cmancs ch~racterist~c~g which may ~ary ~ub~tan-tially fr~m tho6~ of a foot wlth n~ di~ ;isn th~rein.
In e~fe~t, the prosth~si~ vf ~ay in~1sntion i~au-lates the sidew;~y~ ~cuxning o~ a n~ural ankle, in ~ha~ it p~ the energy-stor~n~ ~truc:tur~ o~ the entire foot to twis~t ~ htly fxo~n side ~o ~lde in re3:pc~n~e to variou~;
lo loading cons litioa~, Moreover, such ~ndepen~en~ mc~ ve~n~nt pro~ides addi-tional ~f~ective c~ontact area b~a~ween ~he ~o~om oP the pro~thesie and a con~rontiny ~upporl:ing surfat:~f undex the afore~entioned lateral loaCl~ng condil:ion~, In~a~ Df a si~le c~uter ~adge ~f th~ pro~the~ ontactin~ t~e ~upps:rt:-ing . ur~e~ t~o or D~ore "edgesn ~ay a,c:hiaY~ uc:h ~cn~act, impro~ring t:he tra&t:~on or fr~c~onal ~ntera~tion o~ t~e pro~3the~is on the ~:urfaae.
An~th~r obj~at o~ ~y inven~ion is the pr~tision of a pros~e~ oot o~ the aforem~n~ion~d char~ct~r whic:h inc~ud~s ::ol~nec~ing or reta~ning ~ans ~;uoh a~ a ~trap or ~imit~ng ~he ~o~n~ o~ rele~an~ independ~nt ~oot pc)r-t~on~, or selec:tea one~: o~ w~th rQ~pe¢t ~o ODe ~no~her. ~rh~ su~e~ ~ha~ th~ rg~-s~c~rinÇ~ ~:apabili~ies ~ ~ . . . , - ., .
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of the entire oot ar~ utilized when the Poot ~ pl21ced under cc~nditions c;~f eXtre~Q~s late~al stre~ e~ u~h situ-ation6, the oonnect~ng means effec~ively connect~ s~l~cted of the f~ot por~:ions wi~ a pr~det~rmisled a~uc)un'C of play the?rebetween, whereby at~r one of the ~onnected port~ons has been displaced ~hat predetermlnad distance with regpec~c to the oth~r, th~ ~t~ap ~*ill r~ e that bo~h connç!~'ce~l p~tion~ be 6imultaneously ac:tualt~d in o~ r for ~urther di~place~nent in ~cha~ direction to oc~cur.
I~ ~8 ~ ~urthe~ o~ect of my invç~ntion to pr~vide a prosthetic foot o ~he aforemention~l cha~a~ter wh~
o~ ~Rodular con~igura~ion, re~ul~ng in re~dy s~ embly and ad~uE:tability th~re.~$ . ~he foot of my inven~i on pre~erably ~nGludes ox~fc~ot and heel portion~ th~ ~an be raadily ~5 exc~an~3~d with corr~ ponding~y-c:~5t~uct~d ~o~ ot an~ heel portion~ to provide si~ sd~ust;ment or different spring xat~s to ~3uit the ælze of fo~t o~ the a5~putee ox ~he E~tr~Ld~3, height, weigh~, at~ a~i~it~r ~e~rel of th~a amput*~. There-forer a ranS~e o~ mbina~ions~ of ~pring rate smd 1;~ ze can be 2 o provid~d tc~ ~h~ a~npu~ hieving a natural str~ de and re~;~ience of ~it.
Anc~ r o~jac~ o~ it Yention ~g t:h~ p~ sion of a prostheti~: f~ot o~ the a~or~en~ioned ch~rac:ter in whioh ~he ~ore~s~ot and heel port:i~n~; o~E the pxost~is ar~

f~bricat~sd 8re:~m ~upe~impo~ed laminake~ m~intalned ~n op~r~
'cive relationship ~y an en~ap~ul~ti~g polymer, an~l ~urther in wh~:h ~aid foc~ use:~pti~le to ben~lin~ E~trQs6 ~le~er~
mirle~ by the nu~ber o~ the lam~nat~s and polymerE; in t~e respec~i~re element . ~hu~, the lamina ce6 ar~ ap~ulate~l ~n a pcl~mer ;~nd cap~l8 o~ ~pring stxe~;~ r~ponse a~ ad~ are impc~se~ thereupon during the u'c~ lizag;ion of sa~d fo~t, A further o~iect of th~ i~ention i5 the p~ovi~ion oI~ a pros~2~etic ~oo~ o~ the a~orem~nt:loned chzaracter which con~i2;ts of continuous, int~grally arld simul~anes:~u~ly form6~d attac}~ant, ank~e, arch a~d toe ~:~ctions~ of a fore~oot por-ti~n, and at:~ac~t an~ heel se~tie~n~ of a h~3~al poxt~on, ~;aid ~ections being re~pectt~re~ abr~cated ~ unita~
s~ruc'cures by pol~er ~mpregn~ a o~ per~n;po~;ea reinfor¢~
ing lamina~ main~a~.nea in ~he d~g~rea ~onfiguratlon o~ saia foot an~ sai~l sectivn~; b~in~ c~ f ~prin~ ~tr~8~ gen~r-~d energ~ ~tora~ whereby t~e ~ on c~ he pr6~he~1a ~oc~t to ber~ding mo~ent~ will cau~a u~.foz~ tra~ls~ siorl of spring ~stre~3 t:hrough ~ia ~;ec:!tions o~ ~;a~ o~t.
2~ q~he p~l~er~ ~tiliz~ to @ncap~ulat~ ~he i~ib;~us lam~nae are ~:h~r~ rt~ed by ela~l;ic~ty ~nd ~lea~hility ~3c~
that t:h~ f~o~ prels~a~ deiEle~ts prc-ps7xtionall~ tt:~ th~
engagement of said pro~;th~tic: :~oot ~ h an ad~ nt ~aur~oe, causing ~h~a re~;ultant ener~ te~ be ~stor~d an~ 3e$~u~ntly , ~ ,.,. ,~ .-; :. .

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relea~3ed when the gai~ o~ the ampu~e inaorporat~ng th~ t and ll~t components re;ult~ in the util~ za!tion o~ ~he s~sxed energy and ~ c:on~;equent S~Uetic~rl of the ~3ner~y expende~l by the amputee.
In ord~r ~o i~part a co$metic a~;pect ~o t~e pro~;-th~'cla ~ot, a~ter prope:r ~itting o~ oot: t~ inE~ure 'chat it is properly b~lanced and of ~pproprla~e ~3i2~, the pro~-the~i6 may be encap~ul~,t~ ln a 6u~ably shaped ~;:oE;met~s:
Ishroud. Tl~e shrou~ ~u~;~ be ~uPfi~:~en~ly ~Elex~ble ~ ae! not to inhibit ~e free mov~men~ a~nd ~lexure o the foot, bUt, b~ au~e of the ir~r~nSly resll~ent and ~resæ-a~sorbin~
o~sara~:~eristlc!& of s;a~d ~oot, l~t~le ~epen~ence iæ n~ed~d - UpOtl the snclllary ou~ ion~ng a~::tion o~ e shroud.
Other o~ects and advantag~a~ o~ th~ in~ention will ~e apparent ~rom t~ae ~ollowir~ fication an~ ~e ac:::om-p~ny~ng ~rawing~, wh~ch ar~ ~or ~he purpo~e o ~llustra~ivn only.

Brie~ 12~i~iQ~ c~ ra~ s F~ is a front eleva~otl view o~ ~ pros~he~
2 o construc~ed in ac:cordasl~:e ~i~h t}le t~3at::h~ng~; o~ ~he ~nven-t~on;

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FIG, 2 ~E~ a rear elova~ioh view ~ a pro~3the~
con~t~cted in acc~rdan~ with ~hQ teac3hir~ o~ the inven~
t~on;
F~G. 3 is a sid~ 3vation ~riew o~ a pxo~the ~;
con~:tructed in acc:oraance wl~h ~he ~achin~g~ o~ the inven-~ion: .
FIG. ~ i~; a par~i~lly c~taw~y eid~ eî~at~on ~;ec-tional ~riew, taken alonç~ lin~ 4-4 o~ ~IG. 1:
~IG. 5 i~ ~ partially ~ec:t~onal plan ~iew ~ a prost~e~:is con#~ruc~e~ xdanc~ wit~ ~e teac:h~ngs s:~
the imen~ion: an~
FIG. 6 i~ a ~ec~ional ~i~w, t:aken ~long lir~e ~-6 c7f FI&. s, __ Ref~rrin~ khe draw~ng~, an~ p~x~lcularly t~
FIG. 4 thereo~, I 8~ a pr~ r~l amb,oaim~n~ o~ a ~oot pro~thesls 10 c~on~truoted in accordanc~ h th~ t~ac:h~ngs o~ the in~ren~ion and ~ncl~Yding a~tac:hmen~ m~an2: 12 ~uch a~;
~e)opera~ing ~ul;~ 14, ~olt~ l~i, set screw 1~, pylon 22 and ~:oupling 20 ~r f~ilita~ing th~ ~perativ~2 ~n~age3~r~t ~ th~
~oot Wi'ch a wearer'~ urnp. Attiached ~co ~ a~ao~ent s~an~ î2 and ex'cen~ng downwardly ~h~rogErom ~ plura~ y s3f cur~ilin~ar ~oot po3~:~0n~ 24, $he~wn in the ~sreer~d : . . -: .. :. :: -. ~. , 2~8~

diment ~ a bi~urc:a~ed r~r~foot p~rtion 26 ~n~ h~ or-t~ons 28 ~ecured ~her~ts~.
~he fo~ p~rtions ~4 such a6 ~che ~re~erre~ ~ore-foot portit~n 26 ~u~ther px~erably inc}ud~ an attashment ~e~lon 30, a ç~ur~ilinear anlcl~ s:~ion 3~, F~G. 4, ~n ~ch se~tie~al 34 and a 1;oe ~ection 3~. The heel portion~ 28 preferably includ~ an ~ac:hment seation 38 ~nd a h~el ~c-tion 40 projecting xes~ar~ly 1:here~rom. The var~ou~; ~;ec-~ion~ o:E th~ ~or~oot and heel portion~ re~p~c'cively, are î~ prePe~ f~ed ~n~çTrally with ona another ana ~i~ultan~-ously by thP incorporat~on o~ a plurality of ~aminae e~nbed~
ded in a hax~en~d, ~lexible pol~r, ~imilar ~o th~ ab~ica-ti~n ~nethods taught ln ~ny above-nota~ patents.
T2~e ~oreoot a;ld heel por~ion~2 o~ my ~nventiv~a, as ~e~l a~ t:tle inven~ons of ~y abo~ ne~ed pa'cents, ~nay al so be Manufacture~ by v~r~us ot~ exped~ent~, includin~
in~ct$on moldin~ and~ox th~ ~e o~ kh~moplastic material~
and process~, o~r any o~ a ~nge ~P combinatis:~n~; the~eof.
Among othe~ ~hing~r chopped f~ber ma~r be blen~
in a the~oplastic: or thermo~ esin and t:he r~su~t~ng mix ture in~c~ion }no1ds~ ~n~c> an apprc~prla~3 con~ rat~ n, A~terna'ci~ r or~ad~tio~al.ly, ~e~otsplast~c l~na~ ~y b~
woun~l ~rolmd an in~ec~on-~aoldQ~ core, c~r a ~h~pla~ic resin may b~ ~n~ te~ b~twee~ thermopla~;t~ or th~rmo~

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lam~nae, whereby the laTI~ina~e~ ~e b~nded on'co th~ ~n~ eoted material .
The attachment ~ection 38 o* ~e he~l 3portions ~8 are prePerably s~ac~red ~o corre~pondi2~3 intersectlon~ of th~
cur~ ~ea~ anJcle s~ec~i~ns 3~ an~ the arch ~;ect~one 34 c~f the ~ur~ ear foc~t porti~ 4 . SuCh ~ecu~3ment n~ay ~e pemlanent, throug~ ultan~0~l13 and in~e~ral f~icat:ion or ~hrough ~h~ us~ of epoxy, glue or ~che li3ce" cr m~y }~e demo-~ntabler ~}GS~ 3 ~d 4, through the u~ilizatio~ of ~ol~, ~o nut and wa~her c~c,~i~ations 4~ a~embl E3d through c:orr~spond~
ing holes in ~he ~or~oot and heel port:~ons ~ nd 2B.
Der~ounta~1~3 at~ad~ent i~: pre~err6~d, in that ~ t permit~
~orePoc~t po~ion3 ~o be e~ ec~ly matched w11:~ any of ~ra~i-c3us h0el por~ions ha~ g dif~6!r~Dt ~3p~ n~ ~ate~ more lly disous~d b~lo~r.
As ~ndicated ab~ver t:he ~or~f~oo1~ el portlc)ns 2 6 and 28 ar~ pr~ferabLy fabr~cate~ xom &uperimpo5ed lami-r~ate~ maintaine~ oper~ e relation~hip ~y an en~p~ulat~
ins~ p~l~er and susc~pti~le ~o b~nding ~res$ ~at~ n~d l:~y 2~ ~he thickne~;E; o~ ~ha la~inates. ~rhe pr~rr~d m~torlal~ an~
~a~rif!ation pro~e~ are ~or~ thc~rough~y d~cribed ana explained in ~y a~ men'cion~d U.~. Pat~n~ ~0~ ,547,~13 and 4 r 822, 363, a~d ~n~l~da lamina~e~ ~;uoh a~ ~sPrb~n ~i~sr~3 ana~rlr ~ g].~RS8 or ~ynt~etio ~ib~ uch as ~lar~ Ex~m-- 3.

20b~. 8i~

plary alt~rnative ~ethod~ and mater~ls are ~e~c~rib~d hQre~
inabove .
As illus;~rated in ~he ~coompanying Fi~ure~, the ~efoo'c p~rtion 2~ i~ pre~erably bifurcated in~o ~wo ~oot po~tion~ 24, although addi~onal mul~ciple poxtion~; 24 ~ot ~;hown~ ~ay be ~na~c~ally prov~d~d an~ util~ed wlthout ~epartlng ~rom ~he ~;cc~p~ Or my ~n~ent~n ~u h bifurca~ion or ~lxther divi~lon may 1~ acco~
plish~d thxou~h ~e ~ncorpt)ra~ n of a slot 44 along th~
co~npl~e or sub~tant~ally the complo~ le~gt~ of ~he pros-~hes~s lo. Such a slc~ 4~ may be molded or s~u~se~guently cu~
~nto the pro~th~sis, or ~y b~ aGhie~e~ by the ~u~s!lpo~itior - o~ two or m~re ~o~let~y ~eparate ~ocst porl:ion~ 24 tno~
shown), eaeh o~ whi~h ~ould ba ~ rati~rely ~tac~ed to the a~tac~mant ~eans 12., I t~e glot 44 is ~old~s~3 or cu~ ~nto a s~rlgle forefoot p~rtion 26, ~stress reli~ an~ 4~, ~u~ as a hole, is pre~era~ly pxovided a~s the upper es~d of ~h~ slot ~4, to preven~: unde~ Cl exce~ loadiny an~l ~e~er~orat~ on o~ the pros~e~i2; at that location,. Su~h a ~ol~ be ~0 ~rlll~ or ~old~d ia~o the prosthes~E: 10.
The pro2:the~3i of ~y inven~ion ~s also pre~eri~ly pr~vided with u~der~g pads ~8 and le~er ac~tiRn ~loc~cs S0, a6 descx~ed in ~y ~orem~n~ioned pa'l:~nt~ an~l pe2ldi~g ap~
cations. Such pad ~e~ob~r~ may b~ affixe~ to th~ un~lersi~le : -, ., - ~ ~. , ~, , -.

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of the forefo~t an~ h~el portion~, to c:r~aate a pro811e for the bottom o~ the proC~ i8 10 whic~ corre~pon~s to 'che iD~e~r~or of a shoe. Suoh a pro~ile c~rie~t6 th~ ~oot 10, when the foc~t i~ in an unE;tre~ed ;ta~e, at an app~opriate angle ~or wear~ ng sho~s.
~ ddi1;ic~na~1y, the p~eerred e~odime~ o~ my inve~at~on includes re~ain~n~ or conn~ ng m~an~ 52 ~u~h as a ~trap 5~ op~ratlv~ly att~chad to ~3elec~ad o~ the cur~rilin-&ar oot portions 2~ tllrough the pro~ision of n~, bolt and 1~ washex combirlations 56 o~ ke. Th@ ~;~rap 54 ~ pre~
ably fabri¢ated fro~ impregna~2d can~a~3 or ot~ar flexible, lightws~ight, touS~h ~ eriall and i~ lo¢ated r~mo~a ~om the attachment 2c~0n 30. By pro~fid~ng some play in th~ strap 5~ rather than utilizing a ~aut s'crap, t~le gelec~ed foot 15 port~on~ 24 ~ay ~ x independenUy c~E each other wh~le expo~ca to lateral loa~ing c:onditlon r but ~i~l flex ~ n coor~inated ~anner a~te~ su~ficient mo~e~ent has ~c~urr~ o dr~w t2~e s~crap taut~. Thus, in ~x~rome lat~ral lo~dlng oon-~liti~ more than one foDt porl:~on 24 will ~nct~on ~o ~0 ~bsorb and exer~ ener~y and pre~ nt o~rerloaæ o~ a ~ la ~oot portion 24.
11 be o~o~ to ~ose gki~e~ in the art ~hat a virt~ally in~ini~e ~rl~y o forefoc~t portior~ 2Ç, and h6~el portiorls 28 may be ~abri~ d, ~ h h~ g ~anique . . 1~

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spring ~t~e~:~ re~pon~;e charaateri~ti~ dsterm~nQâ by ~he configur~t~on, compo~:~tlon and a~ un~ c~f ~h~ ~.raricus ~ompo-nent material~ ut~.lized therein. ~he ~or~me~ioned demountable connec:tlon of th~a hesl port~on to the ~o~fc70t S p~rtion there~ore permi~s~ inter~ange~bili~cy o~ those por-tions to matcb th~ ght, str~ d~ and acti~ che~lule of th~ wearer u~ ing ~he pro~the'cic ~oc~.
Tho~:e ~kil~d i~ 'che srt ~ill un~er~;San~l t~at a~a~ment ~nean~ 12 h~Ye b~en de~;cr~b~d h~inabo~e ~erely by way of ex~mpl~, and tha~ many alternative atta~e~t means are a~ailable and ~ay b3 utili2ed without departi~g fr~m th~ scope o~ the in~en~icn.
The attac~n~nt s~c~ion or ~:ect~ons 30, when assQ~-bl~3d wi~ he: attachment ~n~an~ ~2, are u~tantially r~
1~ and oapa~le QiE ~;U ~alning torsional, i~pac~, and other loa~s e~:~ed ~cher~upc~n ~y th~ wear~ du~ing u!3~ of ~he foot 10.
In addition, the inhe~ent r~g~d~t~ of the a~achme~t ~ tion or ~ec:tions prev~n~ th~ ~rc~m being ~i~t~rt~d ~ any way and c:au~es t~e e~feative transmlssion e?~ t~e a~ sai~ l~d~
impo~e~l ther6!~pon b~a~w~n th~ wear~ and the prosthe~ foDt ~0.
~he fc>re~oot an~ hee~ por~iorl~ 2~ an~ an b~a prQvid~d with diff~r~sn~ rlu~er~ o~ '~.a~A~nat~26 to maPca! th~n more or 1~SE: cx~mplâant to load~ tran~m~ted b2~w~ t~e . 8 ~ ~

wearer and surf~ce upon which the ~oot ~0 i~ ~npa~ting.
Con~e~uently, when c:on~ronted wl~ch various ano~ali~ ~n ~
ampu~ee, suah a~ an overwei~ht ~::on~i~ion or exc~ acti~r~ty l~vels, the s~ruoture of the forefoot and heel pc)r'cion~ can be materially modi~ to prc~vi~e ac:tion wh~ h i~ p~eci ely aa3u~tea to the n~e~3 o the ataput2~. Moreover, a ~rari~y of ~ore~oot and h~l po~tion~ 2~ aha 28 can b~ made a~ail-a~l~ to an a~pu~ee, allowin~ ~he ~lex~h~ity of ths proE~th12-~i~ to be a~u~ted on t~e ~a~;i o~ ~he particular actt~i~cy which the amputee i5 underta~ing.
Those slcill~d ~n the art Wil3. under~t~nd ~hat aux-iliary ~lexur~ members ~no~ ~ho~n) such a ~ose de~cribed an~ ~h~swn ~n my co-~?and~ng applic:ations~ 07f293,~24 ~ee FIG.
7 ~erein~ an~ ~7/337 r 374 may be ~~ac:iously utili~e~ ~ n cctnnec~ion ~ith any ~ bodi~ent a~ the abcve~esc:~ibe~ imr~
t~on, wi~ut departirlg f~om the ~e:op~ o~ ~che teat:hing~
her~
~n 'cha pre~erred ~odialen~, the ~o~ a~-d h~e7 portions 2~ and 2~ are ~aon~ h ~om~ ~31i~t taperis~g t~f t~c3cn~s~; along the l~nyth ~h~re~f t although tho~
~;kllled ln the ~ rlll und~rs~tand ~;~at ~e~ ~n~entlon i~ noJc ~imi~d ~o uc:h ~ap~ri~g cQnstxllc~iono ~he ~a~erial~ ~rom w~ ~e portic7n~ 2~ and 2~
are fa~ri~a~ed are pre~rably xu~:~ a~ provide an ~nergy .

storing, re~ilient, ~pxing-like ~Pe~t. Th~ is, becavLs~
each enS~a~ement of th~ pro~hetit: foo~ ~o with an ad~2lcen~
~ur~ace impre~s~es compre~;~ion, tor5ional~ and other loa~
up~n ~he pro6the~i~ whit:h must be ~3tDred with~n ~he pro~he-S ~ d then, dependen~ upon the str~d~ o~ th~ weare~ e ~e~mpre~#ea upon #aid 6urPac~ to as~leve a natural ~tride c~n~or}ning, ~ deall~, ln all respectg to th~ ~tride of t~e uni~paired li~ o~ the ~ar~r of ~ rosth~ o.
The ~nulti-por~ioned pro~thesi~E; o4 ll~y in~ent~on 1:hu~ pro~de6 ~ c:ompliarlee to l~tera~l sl;re~es and l;:~a~ng not preYi~u:~ly aoh~e~a~e, and ac~c~mpl~siaes thi~ s~esirabl~
re~lt ln a li~ht-w~ig~st and ~e~po3~s~ve pros~e~is. Mora-o~er, the modula~ ty o~ th~ imrention p~ tha p~r~o7;~
mance c~arac~eri~;tic~ o~ t~e p~o~thes~ ~ to be fin~-tu~d and ~5 adju~ted to the par~ioular wei~t, ~ n~ ac:t~vity s~ th~
wearer.
As pr~ usly mentioned, ~2~e attaGhmeDt s~ect~c~n 3 0, the ~nkle s~ac:tion 32, ~he a~c~h sea~ion 34, and the 'co~
s~t~on 36 o~ the ~ore~i~oot poxti~rl 26 ar~ pre~e~ably ~or~ned integrally. Lik~wigQ, t~ae attac:hznent ~ec~ion 3~ and the h~el ~ection 4~ o~ the heel portion 28 are pr~era~ly orme~l integrally~ The csnfi~uration o~ t:he~3e ~ tic~ns i~3 ~ch~
m6~ans whor~by ~en~in~ and ~:ompr~ re load8 imlp~se~ durir~g imp~ngement of the pro~ g~c foot 10 upon an ad~ac:ent ~:ur-~S

- .
~- :

20b~14 face are absQxbed and ~ubsequer1tly r~i~pog~ad upon ~ld sur-~a~e~ ~he~e variou& ~actlon~ are ~ço ~ igne~l that ~y func:tion, E~ tantial~y, to pe~m~t som~ e o~ the ~r-ti~ns 26 and 2~ o~i~ati~n with the multi1?1e fo~ por-~ion~ 2~, ~he prost11~gi~ ~0 ~ua~c~ons ir~ a manner analogous ~o a noDal ~oot and no~mal at~ oin~, p~r~nitting the wearer to experienae a more nstural gal~ and eel with th~
pro~the~ ; than wa~; p~ssi~le ~rith prior art pro~the:e~.
~he prt~thetic foot o~ ~y ~nv~ntion can ~hus be p~o~i~e~ in di~ere~t ~ to oorr~spond ~o the ~ize o~ ~he n~tural æoot o:E the weaxer of the pro~the~is lo~ When suc:h dif~erent s~ z~s are ~rovided, correspolldin~ red~ 'clon or - increa~e in the nw~er of lam~na~ ax~d thi~:3cn~ss o~ ~ape~
any, of ~he ~e~pe~t~Ye secti~ of the ~srefoot and heel 1~ portions 12 and 14 c:~n be made ~o p~ov~ de ox the proper ~lexure o~ ~aid ~eot~ ons .
Moreover, ~he f~exi~i~ o~ tlle prosth~ti:: ~oo~
o~ my in~ention ~aly ~e ~u~har inore~sed, ~hil~ na~n-taln~ng ac:cep~ble ~;treng~h cb~ra~;:teristi~, b~r pro~iding an attxiliary ankle ~embex or an aux~liary ~ore~oot portion tnot ~hown, but ~m~ lar to ~at ~llu~;tratea in my co-p~n~in~r applic~tic:n Ser~ No. 07~337,374). ~ut:h an aux~ ry ~e~e~
or p~rtion wc3ul~ be op~a~i~e~y a~ix~a ~o the fo~e~oot por-- tion~; 2~ tc- prov~.d~ ~0~ lat~e ~novement ~he~ebstwe~en~

. ,. . -., ~ .

~,~. . .

2~8~ ~

Th~ a~orementloned 1exurQ o~ ~h~ rlous ~oot portion6 24 provides th;~ c:~pa~ity ~or lncr~ed ~surPaa~ area ~ontac:t betw~en ~he bottom o~ the pro~the~;i3 10 and ~ con-$xc~ntin~ ~upport;in~ ~;ur~a~ ~urln~ bo'ch the ~npa~t and delivery pha~;e~ c~r lateral loading of th~ pro~the~i~ 10.
Inst:ead of a ~;~nyle edge of the pro~hes~2~ e~ec:~ively con-tac~ng che ~;uppo~i.~g ~aurface, the a~ove~d2s~:r~1~ee~ ~ndepen-dent ~lexur~ of the portions 24 permits c:orrespond~n~ es3~s o~ ea~:h ~such port~on 24 t~ oor~ct ~ha i;~ppor~ ur~a~e, ther~l:\y imp~o~ing th~ t~act~on c~r ~r:~ct~onaI c:ontac~ betwe~n ~ha bottom o~ t;h8 prosthe6i~; ~nd the confror~t~n~ sur~ace.
Th~ ~o~;the~ls ~f m~ ln~ntion ha~ ~en ~l~scribed ~ith #ome par~qula~y bu'c the ~p~ci~c de~ and co~-6t~uctionS d,~Salo~Qd are ns~ ~o be takes) a~ ~elim~ g of the ~ venti~ in~that va~i~ug m~ific~t~on~ ~7ill at onç-~
mak~ then se~es ~pparent ~o ~o~e of ordinary sk~ n the art:~ a~ll o~ w~ 1 no~ d~p~rt ~rom ~he ~enc:e o~ the inv~n~ion and all ~uch t:bang~s and modi~ic:at~oIl6 ar~.
in~nd~d ~o be on¢om~?ass~d wi~in ~he appen~d al~im~.

-- . , ,: , : : , . j .. ,

Claims

1. In a prosthetic foot, the combination of;
attachment means for facilitating the operative engagement of the foot with a wearer's stump; and a plurality of curvi-linear foot portions operatively attached to said attachment means and extending downwardly therefrom to contact a sup-porting surface, whereby said foot portions may interact with the supporting surface independently from one another.

2. The prosthetic foot of Claim 1 in which said plurality of curvilinear portions are of similar shape.

3. The prosthetic foot of Claim 1 in which one or more of said plurality of curvilinear portions include for-wardly extending forefoot sections having rearwardly extend-ing heel sections operatively connected thereto.

4. The prosthetic foot of Claim 3 in which said heel sections are detachably connected to said forefoot sec-tions.

5. The prosthetic foot of Claim 1 or Claim 2 or Claim 3 or Claim 4, further including connecting means for operatively connecting two or more of said plurality of curvilinear portions to each other at a location remote from said attachment means, whereby the movement of said con-nected curvilinear portions relative to each other is lim-ited.

6. The prosthetic foot of Claim 1 or Claim 2 or Claim 3 or Claim 4 in which said plurality of curvilinear portions is fabricated from superimposed laminates main-tained in operative relationship by an encapsulating polymer and susceptible to bending stress determined by the thick-ness of the laminates.

7. The prosthetic foot of Claim 1 or Claim 2 or Claim 3 or Claim 4 in which said plurality of curvilinear portions include continuous, integrally and simultaneously formed attachment, ankle, arch and toe sections, said sec-tions being fabricated as unitary structures by polymer impregnation of superimposed reinforcing laminae; said attachment, ankle, arch and toe sections being capable of spring stress generated energy storage whereby the sub-jection of said foot to bending moments will cause transmis-sion of spring stress through said attachment, ankle, arch and toe sections.

8. The prosthetic foot of Claim 7, further including a corresponding plurality of heel members having an attachment section secured to the intersection of said arch and toe sections and a heel section extending rear-wardly therefrom, said heel members being fabricated as uni-tary structures by polymer impregnation of superimposed reinforcing laminae and being capable of spring stress gen-erated energy storage.

9. A prosthetic foot including: a forefoot por-tion incorporating an upper attachment section for facili-tating operative connection to a wearer's stump, a curvilin-ear ankle section, an arch section and a toe section; and a heel portion having an attachment section secured to said forefoot portion and a heel section extending therefrom, in which said forefoot and heel portions are completely or par-tially divided into similarly-shaped segments capable of movement relative to one another.

10. The prosthetic foot of Claim 9 in which said division into segments constitutes a bifurcation of said forefoot and hell portions.

11. The prosthetic foot of Claim 10 in which said bifurcation is defined by a slot in said forefoot and heel portions.

12. The prosthetic foot of Claim 9 in which said securement of said heel portion to said forefoot portion occurs at the intersection of said arch and toe sections.

13. The prosthetic foot of Claim 9, further including connecting means for operatively connecting two or more of said segments to each other at a location remote from said attachment section, whereby the movement of said connected segments relative to each other is limited.

14. The prosthetic foot of Claim 9 or Claim 10 or Claim 11 or Claim 12 or Claim 13 in which said securement of said heel portion to said forefoot portion is detachable.

15. The prosthetic foot of Claim 9 or Claim 10 or Claim 11 or Claim 12 or Claim 13 in which said heel portion is fabricated from superimposed laminates maintained in operative relationship by an encapsulating polymer and sus-ceptible to bending stress determined by the thickness of the laminates.

16. The prosthetic foot of Claim 9 or Claim 10 or Claim 11 or Claim 12 or Claim 13 in which said forefoot por-tion is fabricated from superimposed laminates maintained in ceptible to bending stress determined by the thickness of the laminates.

17. The prosthetic foot of Claim 9 or Claim 10 or Claim 11 or Claim 12 or Claim 13 in which said forefoot por-tion consists of continuous, integrally and simultaneously formed attachment, ankle, arch and toe sections, said sec-tions being fabricated as unitary structures by polymer impregnation of superimposed reinforcing laminae; said attachment, ankle, arch and toe sections being capable of spring stress generated energy storage whereby the sub-jection of said foot to bending moments will cause transmis-sion of spring stress through said attachment, ankle, arch and toe sections.

18. The prosthetic foot of Claim 17 in which said heel portions are demountably attached to corresponding of said forefoot portions to permit heel portions having dif-ferent spring rates to be secures to said forefoot portions of said foot.

19. The prosthetic foot of Claim or Claim 10 or Claim 11 or Claim 12 or Claim 13 in which said heel portions consist of continuous, integrally and simultaneously formed attachment and heel sections, said sections being fabricated as unitary structure by polymer impregnation of superim-posed reinforcing laminae; said attachment and heel sections being capable of spring stress generated energy storage whereby the subjection of said foot to bending moments will cause transmission of spring stress through said attachment and heel sections.

20. In a prosthetic foot, the combination of:
attachment means for facilitating the operative engagement of the foot with a wearer's stump; and a bifurcated curvi-linear foot portion operatively attached to said attachment means and extending downwardly therefrom to contact a sup-porting surface, whereby the resulting bifurcated sections of said foot portion may interact with the supporting sur-face independently from one another.

21. The prosthetic foot of Claim 20, in which said bifurcated curvilinear foot portion includes a forefoot portion and a bifurcated heel portion detachably mounted thereto.