CA2061791A1 - Prosthetic foot incorporating adjustable bladders - Google Patents

Abstract

Abstract of the Disclosure:
A prosthetic foot is characterized by the provi-sion of one or more bladders to vary the performance charac-teristics of the prosthesis. The bladders preferably include multiple chambers formed by full or partial bifurca-tion of the bladder, and may be tapered to permit operative alignment of the bladder with certain structural members of the foot. The pressure in the bladder is preferably alter-able through the provision of valve means communicating with the bladder. A retaining strap is preferably provided to limit the movement of certain structural members of the foot with respect to other such structural members.

Description

2~6179~.

Thi~ imrention re~ate~ to prosthe~;e~ in ges~ral, and specifically to t~ u~e o~ an ad~stable bl~dder in a prosth~sis suoh ~; a pros~c~e'cic ~oot, whicb bladd~r i5 u~e-~ul ~o ~odify~or flne-tun~ the p~r~orm~nc~ ah~racter7~ s of t~e prosthesis~ I~ particula~ he blaæder ~ay be ~uxta-posed ~o Yarious s~ructural ~n~ber~: o~ ~he p~os~h~sis to "~hion'~ or oth~rwise liDi~ or modify ~he ~no~tements ther~of.
Althou~h ~nany prosthotic ~evi::s }~av~ a~tempted to simu~ate the am~ula~io~ a~ a nor~al . oo~, v~tuall~ ~11 of ~he~ ar~ not readi~y adiustabl~ in ~ar~ns of th~ix perfor-manc:e charact~rist~:c~. Thi~ ad~u~ta~ility i~ espec:~ally desira~le a~o~ a~pute~ who pa~i~ipate in a variety physical ~¢tiviti~s r~uirlng vary~n~ level~ of ene~y-storing an~ -r~leasing attr~utes.
Certainly, ~m~ prior a~t d~Yl~s ~ore nearly aahleve the de~ir~d ease o~ ~diustab.~ity t~an ~ other~. :
Po~ ex~ple, se~ my ~.S. Le~te~ en~ ~o~ 4,5~7,~13 ~or ~y inv~nt~on relati~g to a "~mposlte Prostheti~ Foo~ and ~e~, and Un~ted States ~ett~x~ en~ ~o. 4,g~2,363 ~or ~y ~n~Pn~

20~791 tion relating to a 9'~odular Compo~ite Prosth~i Foo'c and Leg" . A.lso, my pending applica~ion~ Se~ial No~. 07/337, 374, 07~5BS,~20 and 07~293,824 disclo~ pros'chetic ~oo~ d~Yice~
with ~imilar pr~erred material~ and met~od~ of manu~a¢turo, and with corresponding ~ene~it8 'cher~ro~.
Eac:h of ~y aforB~entio~d inventions is character-ized ~y liyh~w~i~ht, ~l~ngat.ed ~tructure~ inc;orp~rat~ng polymer improgna~ion o~ ~auperi~po~ad rein~o~cing laminae maintained in th~2 desired oonfigu~a~ior~, S~c~h c~n~lgtlra-1~ tions arld cc~ns~ructio~s provide ~h~ de~3ira~1e characteris-tics o~ streng~h and 1exibility il~ the p~o};~he~ic ~emb~rI
and achi2ve a si~au~ation o~ the p~r~oxmance of na'cural ~eet wh~c:h had pr~vious~y not been attaina~le. Su~:h prs:,~;these~
may be provided i~ ~aodular sss~lies, whereby t~e partl~u-lS lar p~r~ormance chz~x~cteri~t~c~ o~ a ~iv~n prosth~sis m~y be ~dapted and readily a~u~;t~d ~o ~e~t the need ~nd activi~y level o~ thc in~ridual patiellt.
No~wi~;~andi~lg t2~e valuablç~ ~ontributiorl and chara~teri~ti~s o~ my a~oremen~ionad pat~t~ aal~ pPnding application~ an~ spec:i~ically ~e m~dul~ri~y tllereo, the a~ljust~ent o~ ~hose prost}~eE;es is re~ati~ely invoIved in co~pari~on to that of the pre en~ inv~tionO A~y ad~ustment o~ ~he p~ar~ormane ~arac:te~i~t;ic:s o~ 'cho e pros'chese~
broadly r~quire~ ~e dis~embly o~ a cc?v~ring shro~d ( i~

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2~791 pre~ent) and o~ ~tnlctur~ mber~ ~rom e~ch oth~r (th~ough bolt, nut, and wa~;her aombinatio~s, ~or ~xampl~ t~ a new aombina~ion o~ s~ructu2~al ~em3~r~ has bl3en elec:te~, it must ~imilarly l~e rea s&embled.
s Other pro ~hetic foot de~ice~; are even le~s read-ily adju~ted, ana in~:lud2 U.S. Pat. ~to. 3,335,428 ~G Ga~dos, which attempt~ to duplioate the sk~Lletal and ~X~n structure of a n~tural hu~n~n ~oot t ~.S. Pat. ~30, ~, 07~, 5~3 to I.Ang2, whic:h ~ncorpora~es a r~b~er ~orm m~u3~ted in operative rela ~ionship wi~ a rigid ~etallic core, and U.~. Pat. No.
4,645,50g ~o Poggi, whi~ teache~ a prosthetic fos:>t inc:orpc~-rati~g a monol it~ic ke~l or beam of relati~rely massive pro-portions in~ende~ to react to the load o an amputee'~3 ~ody du~ing walking, runnin~, ju~pln~, and ~he likR and to rele~e ~he r~ ultan~ s~ored ener~y to areate ~oot li~t and ~rust co3rplemantinç~ ~e ampu~ee'~ n~ural strid~.
~reover, ~he ~ynam~c p~3r~rmano~ of mo~ prior art; devices i~ r~ vely s~ and immedi~t4, a~d cann~
approach the ~radual "cu~ionirlg" a~i~vable with the use o~
the bladders of the ~n~;tan~ invention in connec~io~ wi~h ~tr~lc'cural ~embers.
Addit~onallS~, wher~ )~lad~er~; have ~e~n utilized i pros~hetic de~tic~a;, ~ey h~ve baen r~ Yeîy l~mi~ed ~n thei~ per~ormance an~ u~e~ulnos~ ~y ~heir ~on~i~ura~:~on.

2~617~1 For exa~ple, U . S . Le'ct~rs Pak . No ~ 7 08 ,, 6~5 di~alo~ a pnq!,u-mat~c ~:ole 36, Fig. 2, which int~ractR wi'ch p~tvrls 36 t~he ~umker 36 wa~ mi~takenly u~d ~or ~wo di~eren'C part~ th~
patent) and 37 and with a æ~ lon 35 of the ~ole 3~ t~ mi~ c fleacur~ and cUs~ioning o'f a r~atural foo~. In U.S. Pat. No.
1,151,1D~4 to Wo~e et al., an a~r bag 3 ~ig. 4~ illed w~'ch air to a de~;ire~ pr~3ssure through ~ valv~ 4 ~iy ~ 2 ) .
~o~h o~ the~;~ pa~en~s di~lose ~el~tive~y k~a6~- u~e~ ~f pneuma~ic d~v~ es in p~o~;thesec;, bu~ include signif lcan~
0 ~or com ng~, suGh ~s the apparen~ 1 kelihood tl~ t the wearer ~ay eac}?erilanc:~ a ~e~l~ng oP being "~igh-c~n~ered", espeaially w~ch respe~::t to lateral stability.

, therefore, æ.n ol~ec~ of ~y inYeni:ion to 15 . provid~ a pros~h~tia IQOt in~o~porati~g b~addex~ w}~ic~a as~hie~e a more s~radu~1 dynamic t~a~si tion during loading t~an pos-~ible with prior art devic~s. ~ The ~o~t pr~3f~rably inol~ades a nu~ber oiE struc:tural ~e~ers ra~rica~e~, ~or exampl~ rom ~a~r~als and me$~ods similar ~o thoc~ di~-closed in my abo re -lis~ed pat~ts and applications, Such memb~rs pr~vid~ ~esira~lP energy-~;tQring a~d ~ re~ oasinçl oharact~ri i;tic~s and ~ay be r~3adily a~æ~3~led and con~ig~r~d :, :

2~791 to receive and int~r~ct wi~h bladder~; o ~he type h~reind~-~:cribed .
~other objec:~c o~ ven~clon ~: to provide a prosthetic ~oot c~ tl e aforeD~entioned charac~er in wh~ch ~e l~la~der or bladder ~ne~ber ~re r~dily ~a~ stable in p~es-eurs, ~ n order to per~it a correæponding rea~y ad~us~men~ o$
the ~eel and per~orman ::e o~ ~h* pro~3~he~ experienced ~y the w~3arer.
Mor~ov~ar, t2~3 preferred embo~i~en~ o~ ~e bladder of- ~r inventiQn ~Aay ~e ~abris~at~d in a ~ariety o~ con~$gura-tion~, includ~n~ those k~aving ~llltiple c:hambers and tapered cross-~ectio~8~ slA~n con~igura'cions~ pa~it the bla~ddar or blad~lers to be po~l~toned i~ unusual ~ut u~ ul locations~
t~i~i~ t~e pros~hesi; an~ ~he truc~ural w.embers ~herlaof, and provide addition2~1 ~ensfit~ ~uch a2~ a l~æs~ned ~e~llnSI -of ~eing ~high-cent~area", a~ de~or~ad ab~v6~., It i a ~urt:ber obj~c:t o~ my it~ventie~n to pro~ide a bladder useful in pro~ hetic de~ic~s su~ a~ a pro~;~etio ~oo~ o~ t2~e a~oreme~ion~d ¢~aract~r. ~n a pr~e~r~d ~ib~d-O iment, and as indicated abov~, ~e ~lad~ler inal-~des ~ean.
~or ad~us~ing t~e internal preæ~ and ~h~ c~rre~:p~Cling ~eel and p~r~c~ance charas::~er~qtic~ o ~e blz~dder ar~d the pxo~:th~sis in~o which it i~ corporated.

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20~791 ~he pro8Shetic de~ic~ o~ ~h~ inv~n~ion, inolud~ng the ~ruatural members and the blad~ers, i pre~eral:ly o:t modular con~igurat~on, regulting in ready ;~8. e~ly and adjus~ y th~reo~, si~nilar to ~y a~r~m~ntioned inven-~iot~ he ~rariou~ c~nponsnts of ths ~oot o~ my inv~32~ion pre~e~ably ¢an be readily excha-ng~d W$th corr~spondirlgly-oon~tructed a~ponent~, ~r e~ren di*~er~3ntly~ o~stru~ d co~-ponents, to prc~ida siæe a~d perîormance a~l~u~;tmen~; and ad~usta~ lity to 3uit the ~ize of foo~ o~ the a2aputee or ~he ~:~rid~, heig~r weigh~ nd ac*ivity l~v~l o~E t~ amput~e, Therefor~, a ~ange o~ co~bination~ or spring ~t~, ad~u~;ta- ~:
bilit;y and ~ize can b~ prov~ded to the amputee, ~ch~ n~ a na~ural ~txide and r~ ilienoe of ~3ai~, ~hl h ~a~; not been ~ull~ ob'ca ina}~le by prior art proe~he~ dev~c~
1~ C:on~e~ ly, t~ oot of my ir~ ion is ¢harac-l;erized by ax~re~e l~ht w~igh~, ins~ant~neous r~pon~e to impos~d load6 and co~-~;pG~in~ly insti~ntan~ous del ivery o~
st:ored ~ner~y w~en 1~ a~ oP ~he wearer ~dioat;~; lth2~ ~
6UC~ ~3tore~ eD~r~r ls to be r~l~ased. qhe wei~ r c~ ~he 2û foc~ may en~Saç~e~ in a wid~ ~rarlety o~ a~;i~itie~; and a2ly ea~;-ily and prec:is~ly ad~u~t the s~ ne~;~ anâ ~3pr~rlg chara~t:e~-istics ac~ording ~ e pa~tic:ular ac~ yt.
Other ~e~ts and ad~rar~'ca~3s o the iinvention will }:~e 4~pparsn~ ~rQin 'che ~ollowing ~;poci~lca~ion aT~d the as::~om~

~ , : -. , . :.:. , 20~1791 panying drawingE:, w~ic:h are ~or th~ purpo~e o~ ~Btrati~n only.

FIG. 1 i~3 a 6ide ~1QV~tiOn V~¢W o a pro~the~is con~ ruct~d in a~ ord3nce with thQ teachingS a~ the inven-tion and inc:orporat~ng a sing~e bladdar ~ne~er;
FIG. 2 i~ a gid~ ele~ration vlew oP an alternativ~
~obodi~ent o~ a prosthesi~ con~truG~ed in ac:cordan~e wit;h the teac:hings of the ~n~ention, and is si~ilar t~ FI~a. 1 bu~
include an additional bladd~r ~em~er and mean~ ~or adjust-D~nt o~ th~ internal pre~sure o~ the bladder~;;
FIG~ 3 i~ a plan ~iew, ~a~en along line 3-~
FIt; . 2;
~I~. 4 i~ an i~aometric Vi13~ C?~ an ~ tabl~e blaA-d~r ~ans constr~c~d i~ acc:ordan~e with t~ t~a~ng~ o~
~e i~l~en~ion;
FIG. S iæ a s~3ctional ~id~ elev~ion vi~w, taken a~ot~g line 5-5 o~ FIGo . 4 FIG. 6 is an iso~atric view o~ an a1terna~e 2Q ~mbodimrnt o~ an adjus~1e blad~e~ mean~ c:on~ ct~ n acs~ordanoe wi~ t;h~ teao~i~g6 og the in~e~or~; alld FIG. 7 ~a a se~t~ona1 ~ide ~ on ~w, t~ken along line 7~7 Df FX&~ 6~ ~

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2~6~ 79~

Referr~l~g to the drawing~, and particularly to FIG. 1 there~, I show a Soot pros~hesi; 10 conatru~::te~ in accordAnce w~th ~he t~achings of the invention and includ~ng S st~uc~ural me~bere 12 and bladder asoan# 14 ~u~h ~; a ~ladd~r memb2r 16 opera~ly a~:sembled th~ i'ch. A sboe 18 i2~ ~hown i~ phantom as it m~ght be worn with the pro~
As indicated above, ~he structural me~ber~ 12 ~nay 3~e fabri~ated, c:c~m~inQd and a E:sQmbled in a wide varie~y o~
shape5, ~iz~s~, and performance characteri tic~l an~ are preferably constructed fro~ matorial~ and metl~od6 described in ~y pre~îously men'c~onad pat~3n~s and pendin~ appl~cation~.
F~r purpc)ses of illustration, F~G. 1 dis;clo~oS structural members including a hE~el portion 20, 2~ forefoot p~rt~on 22, ~5 t d an auxiliary m~b~r 24.
Ial the pre~erred e~odim~r.t, the fc~refoot portior 22 and the aux;i.liary me~ber 24 are op~rati-vely attached t~ a E~ylon ~6 through th~ ~5~ o~ nUt and ~olt c`~ na~ions 2~ or similar expedi~nt, c~r ~r~ otherwi~ ~dapt~d ~or clperaltiv~
di~;po;ition on a w~arer's ~ np. T~e 1~1 porti~n 20 i~;
operatively ~and pr~3Serab~y demoun~ca~ly) conn~c:tæd tQ t~
for~oot porti on 2~ ~:hrough t~ u~ili&a~ios~ of nut and bc~lt t::ombinations 30 or ~he lilc~.

2~1791 ~he ~adder m~an~ ~ such a~ ~la~er ~em~er 16 is pr~rably ~abri~ate~ ~ro~ a sui~cably strsmg, ~lexl~le, leak-proc~, lightw~ight ~a~eri~l surh aE: u:re~ar~e c~r t~s l~ke. By way o~ ~axample, FIGS,. 4 and 5, the bladd~r may be for~ed by hea~ ~ealing ~ppropriately ~lzed and ~hap~d p~eces of ~aterial 3~ ~nd 3~ t~ eaoh other~ suitabl~ snicknesses of ur~thane have beetl fc~u~d to b8 C~ . 01 tO 0. 0:2 ~nch~, but a wide range n~ thiCXn~ S~: and ~aterials ~ay be utillz~d with ~2f~icaay. Bladder pre~:sures of u~ to ~o psi ~ve been lized with efficaay.
The bladder ~ean~ 14 is pre~era~ly ~wrapped in c:o~ring means 36 fa~ricated o~ ~vlar or similarly ~trong material to prev2r~ the bladder ~eang ~4 ~rQm explodin~
un~ler h~h pressures and to help d~ine ~e final in~ ed 1~ s~ape of ~he ~lz~ad6~r ~aan~ 14~ In pre~err~d en~o~iment6, FIGS. 2; 4-7, cot~exinS~ ~e~ns 36 include~ ctions 33 and 40, whic:h may be S~:itC}~Bd ~oge~er ~a~; ~ndica~e~ at 42) at; th~
perimetes~ ~f th~ ~adder ~a~ber 16, beforça or a~e~ t:h~e ~;ec-tions 38 and 40 have be~n ~ t ~o their deE;ire~ ~inal shapes,.
Tho~:e sl~illed in the art will und~r~tand tha~ a ~r~ety o~
c~verin~ materials an~ hods of f a~riaatior~ an~ as~ly thareo~ ay b~ u~ ed with ~*~icacy, wi~hs:~ut d6~parting from th~ teac~ings o~ loy ~vention.

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- . -2~6~791 ~ladder ~ean~ 14 i~ prefera~ly ~n~losss ~ir, CO~, or a similar ga~-l ike ~ub~tance, bu~ m~y al'csrna~ively enclo~e liquids or ~el~; 3uah aQ wat2r, 8illc:0ne, or th~
l~ke. A2ly such a se~l~ may provld~ e de~ir~3d cl~ mabil~
i~y and GOnSeguen~ ~cuchioning" or energy-s~orin~, ab~orp-tion and release.
To pro~id~ ready adiu~t~ent c~ the ~prin~ ra1:~ and p~r~ortnan&e ~ the prost~e~ o the wearer, bladder maans 14 pre~erab~y incl~d~ adj~stmen~ ~an~; 44 su~ as a PVC o~
io urethan~ tube 46 whic:h is solvent-bonded ~r othelrwi6e suit-a~ly a~ach~ to ~he bladder ~em~sr l~ ~su~-h as at 4~ ~;o as to be ~n fluid or çlas~ous aommunic:at~on with ~he interior ~e ~ladder~
A~jus~ent TneAn 44 ~urt;h~3r pr~er~ly irlcludefi appropriate val~?e m~ 50 on tbe opposite snd ~ the tubing 46. In ~e pre~rrad ~3~odi~ant, ~he valv~ 50 i~ adapted ~o re~eive a needle fro~ an air pui~p ~n~t show~) or ~ro~ a CO;2 c~artri~ge [not shown), a~ ~or~ thor~uqhly des~ribed her~in, and may be dispos~ n a suitable ~rack~:t 52, FIGX. 2 and 3, ~or ready ac~es8~ 1ity to the wea~a?r. The valYe ~b~ ~nay be op~ratively ~onnect~d to t~e ~u~ing 46 ~ ~xpand~n$~ t~e en~ of t}~e 'cubing and in~3~r~Jlng the ~ralv~a ~h~el2l, as ~t 54 or 'chrough ~ae provi~itsn o~ an ~daptor 5a,, " i .

2~7~

Ii~ indica~e~, passa~eway~ ~;uch ~ holes 58, ~Is;.
2, may be proviæed in the ~truotur~l me~mbQr~ 12 to accc~m5no-d;~te ~he tu~ing ~6~ The pas6ag~way~ 58 ~re pr~er~bly o:e a size and are posi1;ioned to f~cilita~e a6sQmbly and a~ula-tion o~ the prosS~esi~ *ithout b~nding or damaglng the in~
An ~lt~rn~t~Ye ~ diment ~0 o~ the ~ladder ~an~
14 is illustr~ed in ~S. ~ a~d 7, and i~ ~abricated and ~perated i n a man~er i~llar to that ~e~cri~ed a~3oYe, but i5 bifurcated or D~her~ise ~ivided to ~nclu~le ch~er~: 62 and 64. This bi~urc~ on may be ~eadiiy ac:~eved l~y heat-ssz~ling a strip 6~ acr~s all ~no~ shown) or a portion o~
'~he bladder 60, or ~ay b~ fabrioatsd in n~erous other ~n-ners~ Such constru~ions ~uay include a wide ~rar~ty of shape (5UCS~ as the m~if~ U-s~hape o~ FIG. ~) and any b8DI-eficial number of c:ha~rs, wh~ c:hamber~ m~y or ~ay nc~ ~e in gase~u~; or ~luid ~om~uniaatic~n witb one another, d~aper~d-ing on the d2sir~d per~orm~nce o~: t~e blad~ r.
~he prt~.rision o~ ~he ~eat~ ale~ rip 6~ in the bladder 60 provides a ~u~er o~ b~ne~its to ~h~3 wea~r o:C
the prosthesis. For axaJnple, ~he s~rip ~G ~ay be util~ze~
to c:~use a tap~r:i~ng or re~us~tiQn in ~ross~ ti~ on along the lsngth ~ ~he bla~d~Esr ~eans ~4, a~; beast 111u~t~at~d in F ~;,.
7. A eapexed bladdQr ~ay be moxe re.~ily ~ posad in C:81:'--. 11 2~ 7~1 tain locations in the pxo~th~sis lo theln i6 a non-~ape~
bladd~r, such as un~3r a struatural hq~el ~er 6~, FIG~ 2.
Such a bladder may al~o pro~rid~ more d~irabl~ or more gr~d-ual cùshioniny ef ~ects ~han ia non-t~pering bla~dd~r .
Ad~ ionally, th8 pro~ie on o~ multlpl~ ~hamber6 ~:uch as c~a~E!rs ~ an~ ~4 re~u~e~ a~d e~fen eliminat~as the above-de~cribedl pro~l~ o~ ~eellng "2ai~h-can~ered". Instead o~ providing on~ y a oen~ral conta¢~ loc~ion be~ween ~e bladdsr m~m~er 60 an~ tb~ o~erlying heel ne~er 6~, ~IG~ 2, the c~a~ers 62 and 64 prc~vide mul~ple contaet s~rfac:~s and dispose suc:h areas of contact lat~rally from the cen~er the ~el me~er 68.
Ano~he~ 3ne~c~al ~n~adi~ica~ion to my i nve~tic-n is the prs~ision of ~ reætraining ~ r~caining m~anF, ~uch as a }5 rap ~0, F~&. 1~ ~he trap 70 i~ ~abricated fro~ a suit-ably tougl~, fle~ible ~aterial ~u~ a~ i~pr~na~e~ c:anvas ~r the li)te, and ls c:c~nP~gured and ass~led with ~he ~tr~
~ural me~ers ~2 and,;~c~r $he b~adder mean~ 14 to . chieYe desired ~re~;s-s~or~g~a an~ -releas~ performanc~ e pro~-~hesis.
For ~xample, t~e trap 70 may :~ op~atively a'c~ached to the ~oxefoo~ por'ciQ~ 22 ~:hr~h the a~oresaid a~sembly 30 of nut:s and ~oltæ, an~ ~ay ~a rel~a3;~1y attached around ~h~ auxiliary E;tru~Sural m~ r 24 ~hrous~h :- : -, , :
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2~1791 t~e provi~ n of Velcro-type fa~t~ner; or similar expedi-ent, ~he ~;trap 70 provide~ a num~r o~ b~nef~ts. Fur exa~ple, if ju~apo~;~d to a bladder ~ember 16, the ~trap may be appropria~ely tighten~d to "~latten" t~e bla~der, thu~
increasing the contas~ ar~a~ between ~he ~tructural me~er~
and ~h~ ~ladder, ana poss;$bly r~duc:In~a the "~igh-oent~r~d"
problem ~i~cu~se~ above .
~oreo~er, res~rai~ing mearls ~;u~ a~; the ~trap 70 may be incorporated a~ ~arious losation~ on tlle p~o~t~le~is 10 to r~;trict the distance ~at a~:sociated struatural ~e~-bert; 12 ~ay move ~r~ one another~ ~he ~etaining alean~ may utilized to pr~r~ t undesira~la exc~ lve l~ading and stra~sing o~E a partic ar ~emb~r 12, ancl to cc~mbine ~e 1~ spri~g-stres~ re. pons~ Aracteri~t~c:s oP the ~oc:iats~
st~uc~ral ~emb~r. 12 u~dèr certa~n lo~ding conditiong. Fs~
exampl~, ~he s~r~p ?O a~ 2lçc embled in ~It;. 1 pB~mit~ tbe auxilia~ e~ber a~ to 35~i~t in rais~g ~h~3 toe o~
pro~esis 10 and to ~ore and re~ea~;e spring en~rgy when ~0 ~he h~l por~ion 2~ is struck on ~h~3 ground ~n ~ron~ of ~he wear~r.
In t~perat~n, thq~ bladders ~y ~e completely de~lated i~ the wear~r de~ire~ the performan~:e charac:teri~
tics of the st~ tural ~em~ers. ~or exa~ple, 1~ $he ass~<-2~17~1 bly illustrated in FIG. 3, 'che Por~ard bladder ~an~ ~
would be no~l-funct~onal if d~la'ced, and the ~prlng-~rç~ss response of the auxiliary member ~4 woul~ be co~in~cl wlth that of t~e fore~oc~t pcrtior ~ o~ly a~ter the ~oreSoo1: por-tion was su~ficientl~ de:1ected ~o con~act the auxiliary mem~er 2 4 .
A5 khe bladder is ~n~lat~ad ~o inarea~in~ pres~ua~gs and volumes, how~ver, the cc~mbination of t~e sprinl3-s1:re s respons;es of ~e ~refot~t portion 22 and the auxiliary ~en~-~o ber 24 e~ective3y oc~ urs a~ter correspondin~ly le~;~ and less de~lec~ion of the forefoot portio~. If t;l~e ~ladd.~r mamber is su~ficlently ~nflated, the ~oreft~o~ por~ion ~2 and the auxiliary mem~r 24 wo~lld Iw~ a ;:t and 2:'~!8Ct in uni-~r~ .
A~ ionally, the ab~v~-in~ at~d ~u~l~ioning e~ct o~ the ~ladder alleans ï4 can ba ~e~sendent upoIa tbe de~r~e ~o whic~ th~ bladdcr ~ infla~ted. Al~ho~ h t2~: blad-d~r will pr~fera~ly alwa~s reta~in so~e aMour~t o~ co~pre~s-ibility and ~'cushioni~ e c:o~pressibililty cauld appr~ac::h 2~ a n~gligi~l~ a~unt i~ the bladder is su~ ie~tly in1a~ed, ther~y ~rirt~ally eliminating any cushio~ e~ac~ during am~ulation of the pro~t:hes~ 10.
Th~s~ s~illed ~n the ar~ will un~e~tan~ Sh~t the ~ladd~r D~ans of ~y illY~antion ~ay b~ utili~ed w:lt:h e$fic:ae:y 2~61~

in a wide ~rarie~y of pros~h~ti~ d~vices, ~rwlu~lng pro0-thetic ~eet ~ substan~ially di~er~n'c con~igura'c~ons 'ch~n thoce disclc)sed in th~ drawings.
It will be o~ ou~ to thos~3 skilled ~n the art that an extre~ely wide variety o~ perfo~ana~ ch~rac:é~ris-tic~ ~ay ~e ac~ hrough ~he ~ncorporati~ o~ ~he ~la~-d~r mean~ o~ my inverltion into any gi~en a~e~ly o~ ~tru~
tural pro~the~ic ~ber~ ~Sor~c~ver, th~ ~election o~ ~nd adjust~nt to a de~;ired ~et of par~ormanc~ charact~ari~tic~
lo may be r2adily a~ieved ~y th6~ wearer o~ the prosth~is without ~ need ~or disa~se~bly and r~asse~bly o~ ~rarious compon~3nts. ~he w~arer m~y repeatedly adjust ~he spring stress respons~ c~act~sristicc ~ the ~oot wit~ v~ e ~i~e or ef~c~rt required. T~ val-re meanR ~0 $ncludes a bl2e~ fun~tic~n to ~elea~e pre~3sure in ~he bladd~3r and, as exp~ained abtwe, pe~i~s re~dy ingl~ion o~ the bladd~r throu~ the u6e of a hand pump, a C02 cartri~ge 8r ~he like.
For ~xa~ple, ~f an indi~dual parta~ n ~por~
or other actiyi~ies wh~o~ s~ t ~e prosthesi~; 10 'co 20 gxea~er loads t~an tho~e of nonaal dz~i~y wear, the ~ladder me~ers 16 may be appropriately in~la~e~ p:~lor to t~e p~
ads o gr~ater a~5t~vity, and derla~ herea~t~r.
~ he prosthe~:is and ~ ds~er mean~3 of ~ny invention h~s ~een de~c ri~ed with ~om~ p~ ularity bUt: the ~p~ci~Eiea 2~7~

designs~ an~ c:on~truc:~ions di~loJ2ed are not ~ b~ t~ken as d~ ting o~ ~he i~verltie~n in that ~riou5 JPo~ific:ation~
will at onc~ make ~ç!3n0elvas appar~nt to t:ho~e o~ ordina~y ~kill irl the ~r~, al7 of wh~ch w~ll not depart ~rom ~he s~ence oî the invention 3~nd all such chang&~s ~Lnd modi~ca-n~; are int~nd~d to ~ encompas6e~ wi~n the ~ppended c1 . ..

Claims (15)

1. In a prosthetic foot, the combination of:
attachment means to facilitate operative engagement of the foot with a wearer's stump; a plurality of curvilinear, energy-storing structural members operatively attached to said attachment means and/or to each other; and bladder means adjacent said structural members, whereby said bladder means cooperate with said structural members in determining the energy-storage characteristics of said foot.

2. The prosthetic foot of Claim 1, in which at least one of said bladder means is provided With a plurality of chambers.

3. The prosthetic foot of Claim 1, in which at least one of said bladder means is formed in a modified U-shaped configuration.

4. The prosthetic foot of Claim 1, in which at least one of said bladder means includes a partial bifurca-tion which divides said bladder means into a plurality of sections while retaining fluid communication between said sections.

5. The prosthetic foot of Claim 1, in which said bladder means includes a heel bladder operatively disposed beneath a lower, rearwardly disposed structural member.

6. The prosthetic foot of Claim 1, in which said bladder means is covered with a protective material.

7. The prosthetic foot of Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6, including retain-ing means juxtaposed to a plurality of said structural mem-bers to restrict the movement of said members in relation to one another.

8. The prosthetic foot of Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6, including adjust-ment means operatively associated with said bladder means to facilitate adjustment of the pressure or volume of said bladder means.

9. The prosthetic foot of Claim 1 or Claim 2 or Claim 3 or Claim 4 or Claim 5 or Claim 6, in which said bladder means contains a gas such as air.

10. An adjustable bladder for use in prosthetic devices, including: a bladder portion; and valve means operatively connected to said bladder portion to permit the desired adjustment of said bladder poportion, whereby said bladder portion may be operatively positioned in a pros-thetic device to affect the energy-storage characteristics of same.

11. The bladder of Claim 10, in which said blad-der portion includes multiple chambers.

12. The bladder of Claim 10, in which said blad-der portion is fabricated in a modified U-shaped configura-tion.

13. The bladder of Claim 10, in which said blad-der portion is tapered in cross-section along the length of the portion to facilitate juxtaposition of said portion to said prosthetic device.

14. The bladder of Claim 10 or Claim 11 or Claim 12 or Claim 13, in which said bladder portion is fabricated from urethane.

15. The bladder of Claim 10 or Claim 11 or Claim 12 or Claim 13, in which said bladder portion is covered with a protective material.