CA2006499C

CA2006499C - Ligament anchor system

Info

Publication number: CA2006499C
Application number: CA002006499A
Authority: CA
Inventors: E. Marlowe Goble; W. Karl Somers
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-12-27
Filing date: 1989-12-22
Publication date: 1994-08-02
Anticipated expiration: 2009-12-22
Also published as: EP0376641A1; AU4728389A; AU625918B2; US4870957A; JPH02246968A; CA2006499A1

Abstract

ABSTRACT OF THE DISCLOSURE
An anchor system that is preferably for use in an arthroscopic cruciate ligament replacement procedure for securing a ligament (37) or (50), or ligament type device, with or without a stint (38), within a prepared ligament tunnel (33). The system includes a pair of threaded footings (11) for turning in opposite tapped ligament tunnel cortex ends (34) and (35) and studs (10), each having an eyelet end (18) or, for a prosthetic ligament (50) is secured to the ligament end, the studs each having a cylindrical body (17) and flared end (12). The stud flared end terminates in a lip (15) wherefrom a lock wall (16) extends at an angle to the vertical to the cylindrical body, which flared end is cross-cut at (19) and (20), forming sections. The stud flared end (12) sections to close together to fit through the threaded footing (11) and flex outwardly beyond that footing end (24), the lip lock wall (16) to flex over that footing end locking the stud therein.
In practice, the ligament (37) with or without the stint (38) is formed into a loop for sliding along the stud (10).
slot (20) into the eyelet (18), or the studs are attached to a prosthetic ligament ends in its manufacture, the pair of studs and connected ligament and stint for manipulation through an arthroscopic port (36) formed into the patient's knee, each stud for seating into a threaded footing, the studs each locking therein with the ligament stretched across the knee intra articular joint. Whereafter, tension on the ligament can be adjusted by individually turning the threaded footings appropriately into or out of the cortex threads.

Description

Z~)~6~9~

~, _I F I ~ A

~ACKGR~UND OF TH~ IMV~N~IO~

Fleld of the l~y~n~ion This inventio~ relate~ to li~ament anchor sy~tem~ and device~ fr;~r u~e in an artho~copio surgic~l procQdur~ and par~icularly rela~e~ to repalr or replacemenk of a kne~
cruoia~ ligamen~.

In the di~iplln~ of ~rtho~aopi~ knee ~urg~ry, ~or a p~rticular prooedure, a Gurg~on will ~orm a tunnel through the tibia, in~ra ar~iaular ~oint, and ~emur, that i~ to reaelve an Ant~rior or poatarlor ~rucia~e llgament maintained therein.
~h li~amen~ ende can b~ atta~hed, a3 with ~tapl~, to the ~moral andJor tlhi~l cortsx surfac~, maintain~ng th~
liqam~nt, under ~en~lon, aoro3~ the in~a a~lculax -)oin~.
Example~ o~ arrang~men~ ~or attaching llgamen~s to tha tl~lal and femoral ~oxtex~s a~e sh~wn in a Unita~ ~lngdom Pat~n~, No.
a.~. a,os4,46sA an~ a pa~ant o~ tho pres~nt inventor~, U.S.
P~ont No. 4,772,286. Al~o a U.S. Pate~t Applicatlon, Serial No. 246,324, of ~he pr~sen~ in~entor~ ~n~itled "Apparatus and ProcRdure Eor V~ri~ying Ieometric ~igament Po~itioning~', fllad S2pt~mb~r 1~ 88, teach~ that a ligament end can b~ ~cured ~o ~ ~hrea~ed ~leev~, ~he 918ev~ f~r turning in thre~d~ formed in a ~emoral or tib~al cortex.
Nei~her the Rbove ci~ed Un1tad Kingdom pat~nt, nor the .. aarlier patent and patent applioation of ~he present inv~ntor~, hew~ve~, ~ ncludeB A pair of longitudinally open ~, .

, ", .. " , . ~ . . . .

~C)06~

~hreaded ~ooting~ ror ~urnlng in tunnel co~ex end~ ~nd ~or receiving ligament mountin~ ~tud~ ad therein, a~ dve~ the pxe~en~ invention. Further, unlilce earlier ligament ~aahment arrangem~nt~, ~he pre~en~ invention pxovide~ fer bath placing a ligament and/or ~int in ten~lon between the ~tud~, acroiE; the in~ra artl~ular ; oin~, ~nd provide~ ~or ~uE3ting the ten~ion &~ either ~h6a femoxal or ~lbial cor~ex tunrlel end~ .
~Ry OF~q~ INt7EN~,~QN
A prinalp~l ob~ ec:t of the present invention to pxovide, ~or u~ ~ n a kn~e artho~copio suxgical procedure, a ligament anahor sy~tem ~or ~ecurln~ a biological or pro~heti~
~ i~ament, or ligam~n~ type devic~, With or without a ~int, as a repla4ement ~or ~n anteriox or po~texior oruciate llgament.
Another o~ 8at of ~ the presen~ in~ention 1~ to provlde an arrangement ~or ~¢urinç~ a ligament, ligament typ~ device, with or withou~ a ~tint, within ~ pr~par~d ~ru~iate ligament tunnel t~iat i8 ~orm~d, through th~ pa~i~nt~s fe~ur, in~ra artlaular ~oint ~nd tibia, wher~ the in~tallation i~ ~ompleted ~h~c~ugh an artho3aopic port lnto the knee, and wi~h the ~inal l~am~nt tensionin~j~ Ad~u~d at th~ ~emoral or tiblal cortex tunn~l end or snde.
Ano~h2~ ob~ e~ o$ the pr~sent invention i~ to provide a 8y5t~m wh~re, after he~ling, ~0n~ion on an ln~talled ligamen~, 1 lgament typ~ devlce, wlth or withou~ a ~tint, can ba relea~ed a~ ei ther the ti~;ial c~r ~emoral cortex en~ of ~h~ ligament tunnel .

Z0~6~99 \ An~thex obj~t o~ th~ pre~ant lnvenkion ~ to pro~ide a~
end ~oupllng~, a palr o~ tu~ for mounting a ligament, or ligam~n~ t~pe ~evi~e there~e~w~en, wi~h ox withou~ a tlnt, ~a~h stud rOr lndividual ~oupling ln one o~ ~ p~ir ~f thr~aded ~ootin~ that are individually turne~ into the respective ~emoral ~nd tl~ial ~ortex tunnel end~, the studs to turn freel~ within ~he threaded ~ooting~
Still ano~er ob~ect o~ the pre~ent $nventlon i~ to prov~d~ a ligament an~ ~in~ mounting ~ha~ is e~ily in~talled ~ring a kn~e ~r~ho~copi~ giaal pro~dure th~ clude~
~tud~ wh~rebe~we~n the ligamsnt 1~ maintained that ~re indi~idually mounted and di~mounted into threaded footings th~ ar~ ur~ed in~o the opposite tunnel end~, wi~h final ~cen-~ior~ adjus~me~ to be made by ~urning th~ reRpe~tivR
thr~ad~d ~oo~ing~ int~ or ou~ of the ~emoxal and t~ bizll ~ort~x t~nn~l on~e.
S~lll another ob~ect og the pxeeent inv~3nti~n i~ to provide a syst~m oP p~lr~ o~ ~tuds and ~hx~aded ~c~o~ingF;
wh~r~, with ~n ~ncreasing tsnsil~ force applied throug}~ a ~tud that i~ ~at~ ~n a foot~ , the ~ooting thraad~ will tend to X outwa~dly into th~ th~eads o~ a tappe~d cortex tunnel end pur~h~ing a~ditional holding ~trength.
Still a~otller ob~eo~ of the pra~ent invention i9 ~:0 provld~ a llgament anohor ~ystem th~t m~y be biod~gradable ~or moUnting a llgament, or ligament type device~ witn or without a ~tint ~ with~ n a pr~pAr~d ~ruoi~e ll~amen~ ~unnel, arld ~r r~lea~lnq th~t mountinq aft~r h~aling, ~, 2()06~9~

Th~ pr~6en~ inv~n~lon iB ln a 1 igame~t ~nchor sy~ m that ~nolu~es a pair o~ ~tud wh~rebe~tween a ~lological llgam~ntl or t~e llke, 1~ to be poE3itionQd, ~a;::h ~ aving ~n outwardl~ ~larad ~n~A k~r~ninatin~ in a llp. The ~ud ~lar~d e~ld is e~entially pie ~haped to slope rearwardly toward~ a ~lo~ed eyelet ~tud end and in~lu~e0 a aylind~i~al ~ha~t t~erel~tween. llhe stud rl~ed end i~ ~ro~ ut in~o the cylindr~cal ~haPt, whlch cut~ ara at Approxim~toly ninety ~90) degr~ lnor~ment~ to each o~h~r. Th~ ona pAir of cut~ to Align wlth the ~tud ~yelet erld, and the other pair aligned to ~l~ec:t tho eyele~ ~nd op~n portlon. Whlch bl~ea~ ng pair o~
cut~ are pr~Perably aon~inued in~o that ey~let op~3n port~on.
An open passage i~ ~hereby ~o:~med frem the stud cro~s-au~
~lared end ln~o ~he eyelet to allow free pa~a~e of a li~amen~, ~tring, or the like, ~ ed therethrou~h. Fc~r a pro~he~io, ~e ~tud~, leE~8 the eyolek ~nd~, are ~ecured, aq ~n the manu~ ure ~o tho pro~t~etic~ llgament ~nd~.
~ rhe pair o~ ~uds are tP i~ indlvid~ally in ext~rnally threaded ~ootin~ . ThR threi~df~d f~oting~ elre e3~antlally olbev6l~ ~nd ar~ turn~ ~n a tapped ligamQnt tunnel ~ld c:orte~x.
Tho etud, at itN ~lared end seo~ion, will ~lex inwardly a~ the cro~-cut~ wh~n pa~ d through tha threaded footlng. The ~tud fl~red en~, a~te~ that p~sage, to ~lex or ~prlng ~utwaxdly wh3n i~ travel~ beyond ~he thx~aadud ~ooting end. The ~tud inaludes a ~l~red ond l~p t~at wtll extend beyond, ko overl~p, the t~lread~ ~ooting end. ~;ac~ threaded ~ooting, ~o~ ~n a~t2rior cruc$~te l igam~nt r~placemen~ procedur~ arranged for turning in a tApped ~nd of a llgame~ tunnsl. Which ~unn~ r an ante~ior arucia~e ligament, extend~ from 'che ~)06~9 femor~l Anterol~tera~ cor~ex, ao~o~ the in~ra artic:ular j~lnt, ~o th~ ti~lal cortex at th~ ~bial tubero~ity. The thread~ of e~ch ~hread~d footing are ~loped appropri~t~ly to ~bi~" or ~;llde~', at each t~read ~llght into the tapped corl;~3x thread~ ~o as ~o ~u~thex lo~k the ~ooting in th~t cortex when a ten~ile ~orae i~ applied a~ would tend to pull the ~tud out ~rom t~ea rOo~ing.
The longltudlnal pa~age through eaoh threaded footing i~ interrlally walled at one end, a~ with a hsxagonal cro~s-section, ~o r~celve a driver fl~ted therein ~or turning it into ~h~ tapped cortex. ~urther, opposi~cR ~x~rn~l ~lo~ may be ~ormed lonyi~udin~lly in the footing, to a depth ~u~t below the ~hr~ada and proximate to on~ ~nd, for raceiving flat tab~
o~ ear~ of a ~traddl~ ~ool that ar~ fitted tllerein i~or turning the ~eated ~oo~ln~. The ~traddle tool ~a~ tabs or ea~ a~e ldontiaul and ha~ hick~e~s ~h~t 13 l es~ than th~ ~ootlng ~hread height ~o a~ to allow th~ ~ootln~ ~o be turned Preely ~nto ~r out of tha tapped cortex.
Xn pract~ce, Por a blologl~al liga~ent, the footing6 are lndivi~ually turnRd, utilizlng ~ drive~, an ~pprop~iate dl~tanoe ln~o t~ re~p~cti~e f~ur and tibia cortexoa and the dlst~nc* b~tween the oppo3ite ~ootlng end~ 1~ determined. An appro~ia~3 leng~h o~ llqament or ligament ~ype d~vic~l qith or w~ thout ~ ~tint, or a ~tlnt alone, is then ~ormed into a oon~inuou~ loop ~ncl i~ rlt~Od or ~trung through and betw~en ~ha pair o~ ~tud ~y~lot~. Wi~h the knee ~1QX~d appropriately, the total di~tan~ betws~n the ~tud ~lared ~nd lipe should be approxlm~t~ly equ~l t~ the ~paoing di~tan~e betwe~n th~
oppo~ite footing en~

,~"2`,.:: J
Zl-~)6499 The linkqld ~;~ud~ c:~n be ~ltte~ through an ~rthc~coplc port fo~ned into the kne~ And ~a~h ~tud i~ m~nipulated to fit througl~ one o~ ~he thr~aded footlng~a The c~ne ~tud 1~ ~it'cQd through the 1 igament ~lnn~l and la ~;et into a ~ir~t thre~ded footing, and th~ ~ec:ond ~tu~ i~ maintained withln the knee while tl~ eaond th~aded footing is turned into l:he ~ortex.
There~$ter, the ~ec:on~ ud can be m~nipulated by ~ 3urg~0ll op~rA~ing ~hrough t~e arthoscop~ ~ port, who ~lide~ the ~tUd lnto the socc?nd thr~aded foo~ing, ~tretahlhg the 1 ~gamant, with or without otlnk, the~ebett7i3en. Ten~ion i~ ~hen 'cested by movlng the 3cnee and, i~ a~ ad~u~tment i~ needQd, one or both of the ~ooting~ can be turl~ed ~urther lnto ox ou~ of th~lr re~pective cortex eat~ from withouk the knee, utilizlng the ~traddle t.ool.
J;r it~ i6 d~lred tO relea~e tlan~ion on th~ ligament and~or ~tint, a~te~ th~ bon~ growth ha~ anchor~ the 1 ig~ment, ~ mall i noi~ion ~n be ma~le int:o the knee, to expese ~n end o~ thq ligAment tunnql, ~o a~ to provide acca~3 ~o the . t~ld Plared end. Whiah ~tud ~l~red and, b~l~w t~e lip, a~n the2l be cut, ~llo~in~ th~ ~tud to ~lid~ withln the ~oo~ing, relea lng ~ansion on the llga~nent dnd/or ~tin~.
~IEF ~SCR~ION~F TX~ D~IN~S
~ he~ nd oth~r objeat~ an~ ~aature~ o~ ~he prs~ent imr~lltion will b~ome more appAr~n~ from th~ follow~n~
de~orlption ln WlliCh ~h~ lnv~ntion ~ ~ d~cribad in detail in con~unction wi~h th~ aaa~mpanying drawinga, F~g. 1 lo a proflle perspective vlew of a a~o~-o~t ~tud and threaded ~ooting of ~h~ invent ~ on ~hown ~ oin~d to~ethe~ a~
A 1 lgam~nt anchor;

~:)064~1~
~ ig, 2 1~ ~ proflle p~rE~peo~ive view of th~ stud o~ Fig.
1 removed ~rom a thre~ded ~oo~ing of the ligament Anchor, wit~
~ blologic:~l ligament ~n~ s~in~ shown ~rranged through an Qy~let end o~ ~h~ ~tud 7 Flg. 3 i~ d~ el~va~i~n ~ lon~l ~iew taken along ~h~ llne 3-3 o~ Fig. 1, showing w.1th ar~ows, the preferr~d ~hread angle~ relati~ ~o tho vertic,al of 1:he orw~rd ~nd r~ar f~ce and ~oc~ing nc)~e;
~ ig. 4 l~i a ~lde elevation view oi~ a putiant's ~n~e with Gkln aov~rin~ ther~aover and wher~in ~n ante~ior crua1 a~e ligamen~ tunnel h~s b~n fo~me~ and the ~emoral and tlbial oortex ~nde tapped and showin~ the thr~aded ~ooting with a f lr~t crosG-aut ~tud o~ Fig . 1 turned in the ~moral cortHx tunnel ~nd, a ligament ~nd ~tlnt ~3x~ending ther~rom ~nd ~rom ~ eeaond cro~-cut etud that i~ loaated within the knee ~nd ~howin~ a d~ivl3r ali~ned w~tll th~ tibial ~orteX end oi~ the l~gament tunn~
Fig. 5 i~ a ~tiRw li~ce that o~ Fi~. 4, show~ng the pair o~ thr~aded ~ookln~s eeatad ln the femoral and tl bial tunn~l qnd~ alld ~h~wing ~ir~t and ~e~ond ~ross-~ut ~t~d~ fltted thc~rein, and the 1 lgamen~ and ~tint ~tretchad therebetween aoro~ t~e intr~ artl~ular ~ olnt ~
~ ig . 6 1~ a viet~ l ike ~ha~ ~ Fi~ . 5 ~howing a ~tra~dle tool ~n~ o~ the dril.v~ar end of ~h~ drlv~r fltted ~hrough the ti~ial ~unn~l end and f itted to turn the ~hreaded r~oo~in~ in~o or out of the tapped cortex;
E`lg. 7 i8 an enlarged view o~ the th~aded foo~in~ and drlv~r with s~raddle tool en~ of P`ig. ~ allgned therewith: and : .

i~O0~99 ~ i~. 8 i~ a ~lde olcvatlon Yl*W or ~ prosthe~ic ligamen'c h~ving ~tud~ 1~ k~ tha~ ~hown in Fi~. 2 ee~ured to it~ oppo6ite ~n~

In ~ig. 1 iE~ shown a profile per~p~Ctive ~ W o~ ~he p~ent ln~antl~rl in a cross-~ut stud 10 ~itted into thr~ad~d foot:~ng 11 ~hown as a a~ drical ~le~t~u that i~
~xternAlly thr~ad~d ~long lt~ leng~h ~nd 1~ open t~rough center lor.gitudinal p~a~. A3 wlll be ~et ou~ her~inbelow, the~ cros~3-cut ~tud i~ X~d in tha tl~r~ded fo~tin~ when slld ~ully t~rough the long1~udi~al pa~sagR~
Fig. 2 ~how~ the cross-cut 3tud 10, h~reina~ter r~f~rr~3d to AB ~tlld, a~ including A ~la~ end 12, that i~ e~entially pi~ ~haped, ~nd ha~ a ~loping W~ll 13 that taper~ out~rardly ~rom a ~lat nosa 14 ~ terminAt1n~ in a r~unded circum~ren~lal lip 15, a~ ~hown be~ in Fig~. 2 4nd 3~ a lock wall :L6~ ~lop~
inw~rdly to int~r~ct tho ~orward end o~ a ~tud cyllndri¢~l body 17 . ~ r~art~lo3t er~d o~ whioh ~yl indr~ cal bod~ 17 ~onnect6 to n otud ~y~let ~8 emà. Whlah ~yelet 18 iB 3hown as ~ oente~
hol~d ~narrow ~ctAngular ~ect~ on ~aurecl at ona end to ~x~end . - .-.
axlAlly ~rom tho aylindrical body. .
Ih~ ~ud 10 l~ pr~fer~bly ~ormod ~ a ~ingle unit r`rom a m~teri~l that i~ ~u:it~bl~ ~or human implan'cation, either ~atal .
or plas~ nd i~ cted to b~ ~om~wllAt re~ nt. ~he :
etud i~ c~ros~-~ut ~long a vertlc:Al plane at 1~ and a ~:
hori~ontal pl~n~ a~ ~0, a~ shown best in Flg. 2. The hori~on~al ~l~t 20 pr~f~rably ext~nds ~rom the ~lar~d end 12, ;~
th~ough the cylindrlcsal body 17, and ~nto eyel~t 18 0 The v~rtical cut 19 ~xtends ~rom the ~ d end 12 ~o ~ :

Z~)064~9 approximatsly ~ mid-peint of th~ aylindrio~l body 17. So arran~d, the re3ilienc:y o~ ~tud lO allo~ the cylindriaal }:)o~y segment~ ~ormed rrom ~l~re~ end l~ along cros~-cut~ l~
and 2 0 to bend inwardly towards one~ another . The diameter o~
the :Elarç~d ~n~ lip 15 ~n ~hereby be ~sduced to le~ than the diameter ~f a longitudinal pas age 21 ~hat i~ ~ormed through ~he threaded ~ooting ll. Acaordingly, to install ~he ~tud 10 ln ~ thr~aded gooting ll, a~ ahown in Fl~. 3, the stud flar~d ~nd ~loplng ~all 13 is ~ d into a th~eade4 r'ootlng at lts ou~wardly ~1A~d end ~2, an~ 1~ urgad th~r~in. In tl at p~AE;6~g-3, the ~tud ~l~red ~nd and cylindriaal body ~egment~ are ~lo ~d tog~her ~t tho ar~ outs 19 and 20, allowing that ~tud ~lar~d end to pa~ into and 31ide along and through thA~
thread~d ~ooting longitudinal pa~age 21.
In ~tUd 10 pa~ge along tn~ throad~d ~ooting ll, a~
~hown in Flg. 3, the ~l:ud ~lArbd qnd 12 will lnter~t and expan~ into lnt~rm~dlate ~ir~t and ~e~ond flared grooVBB~ 23a ~nd ~3b, r~pe~vely, thak may ba ~ormsd around ~he lon~itudinAl pa~ aqe 21 wall~ Intexmedia~a groo~e~ 23a and 23b are ~l~ilarly ~orm~d, each to h~ve forward and rearw~dly ~acin~ wAlls ~hat ar~ nted ~rom ~he v~r~iaal to a~p~oximately the ~ame angle~ ao the stud ~l~re~ ~nd ~loping and lo~k wall~, 13 an~ l~, r~p~ctl~ely. So arrange~, on alignmant o~ the ~atud ~lare~ end 12 with a fir~t or ~econd ~lar~d groo~e 23a o~ 23b, ~hat ~ud ~lared end will ~xpand lnto khat ~lared groove, the ~tud flar~d end lock wall 1~
ooming ~o re~t on t~e ~l~r~d gr~ove rearwardly ~acing wall, prohi~i~in~ s~ud lo with~rawal. With a cont~nued ~pplio~ion oP ~orce on t~d ~.0, a~ eyelat 18 ~nd, ~h~ ~tud flared end 6~

~ oplng wall 13 ~ e over the ~lared groove ~orward wal;, the stud ~lared end and oylindrical body segm~nt~
~le~lng inwardly, ~oward~ ons another, and allowln~ th~ ~ud to continue ~hrough t~ thr~ d ~ooting. 0~ ~ourse, a threaded ~ooting 11 wlthout the ~ir~t and ~eaond .~nt~rmedi~te groove~ 23~ and ~3b, c~n be U~ d w~thin ~he ~cope o~ ~hl~
di~lo~urQ when 1~ i~ deslxable ~o provide ~or relea ing the s~ud ~rom ~h~ t~re~ded ~oo~ing ~o ~ to a~ju~t a ligament or ~int len~h. A~oor~l~gly, it ohould be und~r~ood, a threaded ~ooting 11 with or wikhou~ the ~irst and ~con~
~lar~d groo~ 23a ~nd 23b ~ ome within the scope ~ ~hi~
di~olosu~e.
~ hown ln ~ig. 3, t~e ~tud flarQd snd 12 ha~ pa~d ~eyond ~ t~rea~ed ~ootlng ~loping en~ 24, ~nd ~he lock wall 16 h~ moved outwar~ly o~nr tha~ ~ootlng ~loplng end, ~ao ~tud ~lared ~nd segment3 h~ving ~lexed outw~r~ly. ~ha ~tud 10 i~
~h~e~y s~ate~ in thr~adod ~ootlng 11. This eaating will b~
maintained ag~ln~ an appliaation o~ a ten~ile ~orce on the ~tud 10 ~ oyelet 18. ~n suoh ~o~ce appllcatl~n th~ angula~
~on~iguratlon ~o th~ v~r~iaal o~ th~ ~tUd lo~k wall 16 and ~hxead~d ~04~1ny end 24 i~ ~uch that th~ ~t~d lock ~all 1 will b~ u~g~d ou~wa~dly along the thr~aded footing ~nd 24, pur~ha~ing a~d~ional~holding ~treng~h. Sho~n at arro~ A ln Fi~. 3, an ~ngle of approximately thirty (30) degre~ ~rom the vartic~l h~ beGn ~el~cked for ~o~ming stud look wall 1~ ~nd t~reAded ~oo~ end ~4. In pra~ic~, it 1~ belie~ed ~hat an angle ln ~ rang~ fr~ ten (10) to ~ixty t60) degrces Will ~ork ~ia~factorily for t~B appllaation.

;~)06~99 Por ~ thread~d ~ooting 11 fabrlca~d from a reBilient plastic m~terlal, ao ~hown in th6~ cxosE~ ectic~nal ~iew o~ ~lg.

3, ~uch a~ DelrinTM, an ~ nareas~d ten~ile ~tra~s exert~d on stud 10 wilï act through ~hat etud to aompre~ th~ threaded ~oot~ ng. In such :Cor~e ~pplic~atlon ~he thre~d~d footing thread~ 2~ tend ~o expand outw~lrdly. In 3uah ou~ward expAnE;ion, the thr~ad~ a~e seat~d d~eper ihtO the threads t~pped ln~o a bon~ cortex, ~ur~her purcha~ing ten~lon holding ~t~ngth. A pr~errad thr~aded fc~oti~g 11 i8 formed to have a ~orwar~ b~loping ~ e 27, ~hown ~s anglQ C in Fig. 3, to the vertio~l o~ apprc~xlm~tely thirty (30) ~egree~ and el rearward ~lDping~ fQ~e ~ o~ ~pproximnt~ly l;welv~ t~J) degre~s ~o th~
v~rtlcal, ~hown a~ angle ~. In pr~otice, i~ i~ beli~ve~, a threade~ ~oot:lng thre~d ~o~w~r~ ~lctping ~ac~ 27 of from ~wenty ~20) to ~orty- ~ive ~4~) ~legree~ to t~e vertical, and a r~3ar~7ard ~loplng i~aco 2~ o~ f~om ~aro (0) to thi~ty (30) .
degreQ~ to ~he ~ertica1 Will ~unotion suco~s~u11y ~or t~is ~pp1iaati~n.
~ or A thr~a4~d ~ooting 11t ~ ~hown in ~i~. 3, B tenBile $ox~ ~ppl~d at ey~let 18 o~ ~tud 10 ~ill t~nd to ~ompre~
~h~ fo~ting, urging the threAd~ 25 further into a t~pped cort~x, puro~sing addi~ional ho1ding or pu11 ou~ ~treng~h.
It ~hould, how~r, b~ unders~ood that the ~hreaded foo~ing an~ evan the Btud 1~, n~sd not neoa~uar~ly be manu~aotured ~rom a pl~tic material, su¢h a~ De1r1nTM, ~or ~hi~ to ~ccur~
~h~aded foo~in~ n b~ mnntl~Aa~urod ~rom ~ny ~ur~ic~lly ~coo~t~blo m~t~rial, lnclu~lng ~ m~t~l ~u=h as titanium, ~, :
. .

ZOq~6~9 w~thln th~ 6COp~ oi~ ~hls di~clo~ux~. How~ver, wh2re ~ pl~t~o ma~erial i~ u~e~, ~ 3netal mar~er :~8 i~ p~efer~l~ly lnoluded th~r~ a~ an x-ray markarO
~ or ~urnlng th~ thrsaded footing 11 in~o a tapp~d c:ortex, a~ f3ho~rn in Fig~. l, 3 and 4, the 1:hr~aded ~ootirlg lOhgitUdinal pa~3ga~e ~1 18 pre~erabî.y walled approprla~ly at one end 29 to rec~ive a oompatlble ~31ded driver ~nd ~itted ther~in. Shown b~t in Fige. 3 and 4, the threadad ~oo~lng walled 3nd ~ preferabl~ ~oxmQd ~o have a h~axa~onal cro~
~e~tion that Rxtends along the longltudinal pa~age to ~pprox~mat~ly ~ midpoint, sho~n at 30, Wher~at, the longitudlnal pa~age change~ to a srQooth ~ rcular cro~
3ec:tlon ~rom walled passage end 30 to it~ ~loping end 24. ~he dl~mRte~ o~ which longl~udln~l pas~age ~moc~th portlon i8 such a~ to a~c~mmoda~e t}~e 3id~d end 31 o~ a d~iver 40 th~ ~8 ~it~sd ther~in to engago th~ longl~-~dlnal pa~agQ walled portion 2~ r`or turning~ ~h~a threacl~d ~ootlng.
~ hown in P~ig9 4, ~ and 7 ~ ~the driver 4 0 prR~rably ~nolude~ a h~x~gona~ h3aded end 31, that 1B aligned for ing ~hrouç~h a tibial inal~ion 32 t~ ~rav~l thr~ugh the thrlaade~l Pooti~lg ~m~oth portlon and in~o the walled portion o~
th~ lon$l~ ~udinal pas~age 21. ~he driv~r hsxagonal h~ad~d ~nd ~c~r turr,ing that thr~aded P~o~ing lnto or out of thread~ 34 that are tapped lnto th~ tlbial cortex end o~ a ligam~nt tunr~al 3 3 .
Flg. 4 al~o show~ an~t~er t~r~aded ~oo'cinçl 11 that h~s ~ee~n ~u~ned into threa~s 35 tappe~ into the ~emoral aort~X ~nd of th~ l~g~ment ~um~el 33. A ~tud 10 i~ shown fi~t~d ln the ~emoral c:ortex threadecl ~ootlng 11 wher~f`rom a ligament 37 and , ~ ~. ! ' . ~ . : , . . .

Z0~6~

~lnt 38 ext~nd ~rom th.e ~tud eyelet 18. Th~ ligament 37 and ~tint 38 ar~ ~hown to be con~inuou~ 1OOPB and ar~ l~dividually fltted through each eyel~ end~ ~ o~ a pair of ~tud~ 10. The li~a~ent ~7 and ~tin~ 38 and a ~tud 10 ar~ ~hown in ~ig. 4 po~Jtioned wlthln the pakient'~ knee. In praat.c~ the l~ament ~nd ~int can b~ ~lid along the ~tud horiDontal cut ~0, fr~m the stud ~lared and 12 to ~tud ~y~l~t lB, a~
111U~trAte~ in ~ig. 3~
A~ ~hown ln Fi~. 4, one st~d 10 1~ ~itted into locking e~ga~ement wlthin the thr~aded ~ooting 11 tha~ iæ turned lnto ~h~ ~emoral ~ortex thre~d~ 35. ~hls sea~ing ~an b~
accomplished prlor to ~he tu~ning o~ the ~eco~d threaded ~40tin~ 11 into the tibial ~ortex thread~ 34. Or, bo~h s~ud~
may ~a seated in threade~ Poot~ng~ 11 by a surgeon m~nip~la~ing ea~h stud 10 ~hrough an axthos~pic por~ 36 ~ormed in th~ patient'~ knee.
~ lth th~ patient'~ l~g ma~ntained, as ~hown ln Figs. 4 through 6, and ~he thr~d~d :ootinge 11 ~eAt~d in th~ tibial and ~emoral corteX ~hread~ 34 ~nd 35, respectlvely, the lehyt~
o~ t]~e ligament 37 and ~tint 38 can ba calculated baæed on the ~ist~nce betwean th~ end~ 22 oP the thre~ded footing~ 11 taking ~n~o aco~unt the length~ o~ the pair o~ st~d~ o th~ir lock walls 16 . The 1 ~gam~nt ~nd sti~ ~re ~hown arranyed a~ ~ontirluou~ loops and are fitted through ~h~
eyelet~ 18 ~ the p~lr of ~ud~ 10 . The one ~t~d 10 of the ~air ~$ ~tu~, a~ ~hown ln Fiq. 4, i~ ~itted int~ ths thr~ad~
~oo~ng 1~ that has be~n ~urned ~n~o thrsadY 35 at ~he f~moral c:ortex. ~ho~lgh, of ~our e~ ~ ~tud 10 may be ~irst fitted into th~ thread~ 34 at ~e tibial oort~x. Th~ seQond ~tud 10~ i~

. ~ . ... , ......... . ,. ,, . ~, ~

Z~ 6~
~4 then manipula~e~l withln the ~ne~ by ~ ~Urgeon ~hroug~h ~he ar~ho3copic: port 3 ~, f i~t~ng 1~ in~co the ~eGond t~ead~d footing 11 that has ~een turn~d into the tibial c:orkex llganlent tunn~l end and ~;tretching th~ ligament 37 a~d s~in~

3 8 the~rebetween, ae~ ~hown in F~g . 5 "
Pre~eresbly, ~ hown in Flg. 5, the ligament 37 ~nd tint 38 are maintaine~ be~ween th~ p~ir of studs~ eyelet 18 ~eated in threaded footlngs 11 wlll be und~r a de~ired t~n ile ~;tre6~ hat ~;tro3~ i~; materially di~erent ~han an op~imum 6tres~ ~or the procedur~, one or both o~ the ~tud~ ~o ~n be releasad rom thelr ~eat~ng, and the stud~ pulled the~frora ~llowir~g a ~urgeon to r~ro~m the ligam~nt and stint loop~ to new length~. To provlde such ~3lea~e, one a~ ~oth o~
the ~ud ~lare ends 1~ are compress~ad manually, or with a tool, not. ~hown. ~The stud llp 15 di~met~r i~ ~h~reby appropr~ ately rsdu~e~ ~o a~ ~o allow it ~o be pull~d back through th~ ~hr~aded footing longitudlnal pa~sage 21. 0 oou~e, i~ a threaded ~ooti~g with ~lared groove~ 23a ~nd 23b l~ke that shown in Fig. ~ ln plac~, it will b~ re~ulred ~o provi~o ~or stud rel~as~ wlthin that threade~d ~ooting by compr~slng togethe!r th~ ~lar~3d end ~ nt~ to be mainta:L~ed along the longi~udin;~l until the ~irst ~lared groove 23a 1 p~èd.
~ t~ar the ~tud~ 10 ~ave bQen sea~ed ln 'chs ~Areadocl ~oo~ings ll ~ aB shown ln Fig. 5, ~hould i~ be d~term~ned th~t ~ n~ ad~ustmen~ to the ligam~nt antl ~tint lengtA are r~qulred, ~uch can 'b~3 made, a~ ghown in Fig. ~, by turning one or both t21readsd footing~: 11 into ox out of l;he re~pective fem.oral and tibial ~ortQxe~ Thi~ turning is pre~erab~y )6499 E,~ovided utilizing a ~tr~ddle tool ~n~ 43 o~ drive~ 40. ~he ~ra~le tool end 43 i~ ~or manu~l in~ert~on and m~nipulation through a ti~ial or ~emoral ligament ~unnel in¢i~ion 32 or 39, re pec:tiv~ly, aE~ ;hown Fig. 6. As~ shown ba~t in Flg, 7, t2~e driver 40 1~3 pre~erably A ~olid rod 41 with the hexagonal ~ided end 31 th~t, ~ ~e~ out ~Ibove~ i~ for turnin~ the ~hreaded ~leev~ 11 into a ~pped cortex, and includeEI tha 4trad~1e too7 43 on it opposit~ end. Of ~our~e, the drl~rer body ~an be forme~ ~rom a tu~e within the ~aope o~ thi~
di~closur~.
In ~ig . 7, the drl~er ~traddle tool t3nd 4 3 is ~hown to in~ lude a conaav~ depre~E~ion 44 formed longitudinally ~herein, ohown in broicen llrleg, that i~ to ~æceive a th:r~aded footing ~3nd ~nd ~tua ~lared end n~t~d th~rein. T~ driver ~txad~l~
tool end 43 further lncluqe~ at lea~t a p~ir o~ tabs or ears 4g th~ ~xtend rrom opposite points lon~ltudlnally ou~wardly.
Whi~h tab~ or ear~ 45 ar~ to ~it into slote 46 ~hat are formæd ~rom the i:`ootlng end lnto the thr~ad~ 25 c~f th9 thr~aded ~ooting ~1~ Th~ tabs or ears 45 pre~erably have ~ thickne~s euah ~at, when ~i~ted in~o the slo~s 46, ~heir outer ~urfa~
i! will b~ b~low ~he apax of thr~ad~ 25. So arranqed~ a6 ~hown in ~lg. 6, the ~traddle tool end 43 o~ dri~rer 40 aan be ~ittsd ~hrough a tibial or ~emor~l ilnc~ion, the tab~ or ea~s 45 . j .
travel~n~ below th~ hreads tapped into the fe~noral or ~ibial cortex and fi~ting into the slots 4~ that ar~ fo~m~d in th~
th~eaded ~ooting erld 24. so arranged, the threaded footlI~g 11 C~ e turned ~urther lnto or out o~ th~ tapped cortex, '~ th~reby adju0ting the t~n~ning on the ligament and s~int.

~ :
. .

,` , .`

:
;~0(~164~9 1~
Where a 1~ gament 37 and ~;tint 3~ ha~re been ~hown a6 being uti~ize~ ~ogeth~r, lt ~hould be under~tood that ei~her can be ll~3ed alone or anoth~r lis~kage, ~3UC~ a~ ~ ~endon, a~n be ul ed instead Oi~, or therewith, withln th~ ~cope o~ thi3 di~cloaure~ ~lso, a~ter healing, i~ s1red to relea~e the ten~ion on ;uch ligament and~or ~tln~, thi~ can ea~ily ~e ac:aoYnpli~hed at a femoral or tibl21 lnc~ sion. In euch procedure the inoision i~ opened ~o expo~e a ~ud ~lared end 12, ~hich end i~ ~hen out thereacros~, r~lea~in~ that fl~red end, ~uch ~ha~ the re~ainder of the stud lo will travel ~ack through the threade~ ~oot i ng 11.
w~ere the p~ir of ~tud~ lo ~r~ ~hown a3 separate units *rom liqz~ment 37 and ~tint 38, it ~hould b~ und~r~tood that ~or ~ pro~thetlc ligament 50, like 'ch~t 8hown in F~ ~. 8, the st~ld lo, leF E; the ey~let end 18 can be ~ecu~ed, preferably in the m~nufacturing pro~e33, ~xtend axially ~rom t~e pro~hst:lc 3nt ~o ~nd~. s~ arr~nged, ~unot~oning o~ the pxo~th~tic mont 50 havil~g stud 10 ~nd~ for in~alla~ion ln t~eaded ~ooting~ 11 would ba like th~t de~ribed hereinabove. ~-.,., ~
While a prererre~ smbodiment of ~he present inv-3ntiorl in a 1~ gament an~hor system and it~ use have been ~ho~n and ds~i;cribed herein, it ~hould be app~ren~ that the pre~en~
di~GloEsure 1~ ma~e by way o~ ~xampla only and tha~ variatlons thereto ar~ poss~l~le within the ~aope c)~ the di6c:10s~re wi~hout ~par~ing .~rom ths ~u~j ect matter coming with the ~cop~ of ~he foll~win~ ims ~nd a rQa~onable ~quivalency thereof, whi~h claim~ ~e regard a~ our ln~entior.

Claims

1. A ligament anchor system comprising, a pair of longitudinally open externally threaded footings; means for turning each said threaded footings into a tapped bone cortex;
a pair of stud means, each stud means including a flared end, a body that has a diameter to fit through the longitudinal passage of said threaded footing, and means for maintaining a ligament means thereto, said stud means flared end terminating in a lip wherefrom a lock wall extends to inter act said stud means body, said lip diameter being slightly greater than said threaded footing longitudinal opening wall diameter, which said stud means flared end is cross-cut longitudinally into said stud means body; and ligament means for arrangement between said pair of stud means.

2. A ligament anchor system as recited in Claim 1, wherein each threaded footing includes a flat forward end surface to receive the stud flared end lock wall fitting thereover; and the footing longitudinal opening, at a rear end, is walled to form a hexagonal cross-section for receiving a hexagonal end of a shaft fitted therein as the means for turning said threaded footing.

3. A ligament anchor system as recited in Claim 2, wherein the threaded footing threads forward face slopes at an angle of from twenty (20) to forty-five (45) degrees to the vertical, and the threads rear face slopes at an angle from zero (0) to thirty (30) degrees to the vertical.

4. A ligament anchor system as recited in Claim 3, wherein the footing thread forward face is at an angle of approximately thirty (30) degrees to the vertical and the sleeve thread rear face is at an angle of approximately twelve (12) degrees to the vertical.

5. A ligament anchor system as recited in Claim 2, further including, circumferentially internally grooving of the footing longitudinal opening at an intermediate distance back from the footing flat forward end appropriate to accommodate the stud flared end fitting therein.

6. A ligament anchor system as recited in Claim 1, wherein the threaded sleeve is formed of a DelrinTM plastic material; and an x-ray marker means is installed in said threaded sleeve.

7. A ligament anchor system as recited in Claim 1, wherein the pair of stud means includes an eyelet and that is secured to the end of the stud means body opposite to the stud means flared end.

8. A ligament anchor system as recited in Claim 7, wherein the stud means body is cylindrical and the stud means flared end is pie shaped, the greatest diameter face thereof arranged across said stud means cylindrical body; and at least one of the pair of studs cross-cuts extends the length of said stud means cylindrical body and into the eyelet end.

9. A ligament anchor system as recited in Claim 8, wherein the cross-cut from the stud means flared end into the stud means eyelet end is at approximately a right angle to opposite parallel faces of said stud means eyelet end.

10. A ligament anchor system as recited in Claim 8, wherein the stud means is formed of a resilient material.

11. A ligament anchor system as recited in Claim 10, wherein the stud means is formed of a DelrinTM plastic material.

12. A ligament anchor system as recited in Claim 1, wherein a ligament of the ligament means is formed into a closed loop.

13. A ligament anchor system as recited in Claim 11, further including, as the ligament means, a stint that is formed into a closed loop.

14. A ligament anchor system as recited in Claim 1, wherein the stud means are individually secured to extend axially from opposite ends of a prosthetic ligament.

15. A ligament anchor system as recited in Claim 1, further including at least a pair of equally spaced notches that are formed in a flat forward end of the threaded footing and extend into the threaded footing exterior threads; and tool means consisting of a rod or tube that includes at least a pair of outwardly extending equally spaced bar or tab means that project longitudinally outwardly from said thin rod or tube end to fit into each of said pair of notches, straddling said threaded footing forward end, the ears or tabs seated below the thread apex of said threaded footing threads.

16. A ligament anchor system as recited in Claim 15, wherein the tool means is a straight cylindrical section and the individual ear or tab means each have a thickness that is less than the height of the exterior threads of the threaded footing.

17. A process for installing a cruciate ligament in a knee arthroscopic surgical procedure where a tunnel has been formed between femoral and tibial cortexes through the intra articular joint and ligament origins, and the femoral and tibial cortexes have been tapped, comprising the steps of, turning each of a pair of threaded footings into the femoral and tibial tapped cortexes, said threaded footings each having a longitudinal passage therethrough; mounting ligament means to ends of each of a pair of stud means, said stud means, each having a body that will fit longitudinally through one of the threaded footings, with said ligaments means ends attached to ends of each of said stud means cylindrical body, each of which stud means includes, on its other end, an outwardly flared end section that terminates in a lip, which lip has a diameter that is greater than that of said threaded footing longitudinal passage, and which stud means flared end is cross-cut longitudinally into its cylindrical body; and installing each of said pair of stud means flared ends into said threaded footings, each stud means flared end collapsing along said cross-cuts to fit within and pass along said threaded footing longitudinal passage until said stud means flared end lip emerges from and said flared end lip flexes over a threaded footing end thereby locking said stud means in said threaded footing, the ligament means extending therebetween across the intra articular joint.

18. A process as recited in claim 17, wherein each threaded footing longitudinal passage is sided at one end to receive a tool having a like sided end arranged for fitting through a cylindrical portion of said threaded footing longitudinal passage and into said threaded footing; and ??rning said tool and threaded footing into the tapped cortex ends of the tunnel.

19. A process as recited in Claim 18, wherein a first threaded footing is installed in a tapped cortex end of the tunnel and receives a first stud means fitted therein; the second threaded footing is then installed in the other tapped cortex end of the tunnel, and a surgeon operating through an arthoscopic port formed into the patient's knee fits said second stud means into said installed second threaded footing and urges said second stud means therein until said second stub means flared end exits said second threaded footing and said second stud means lip flexes over said threaded footing end.

20. A process as recited in Claim 19, further including the steps of, adjusting the tensile stress exerted on the ligament means stretched between said pair of stud means by releasing, at a tapped cortex tunnel end, one of said stud means out of its engagement with a threaded footing as by closing the stud flared and lip segments together to where said flared end lip circumference is less than that of the threaded footing longitudinal passage, releasing said stud means that then slides back along said threaded footing longitudinal passage; and, through the arthoscopic port, reconfiguring the ligament means so as to appropriately lengthen or shorten it.

21. A process as recited in Claim 19, further including the steps of, for finally adjusting the tensile stress on the ligament means, turning the threaded footing into or out of said cortex threads at a tunnel end.

22. A process as recited in Claim 21, wherein the threaded footing includes at least a pair of equally spaced longitudinal slots that are formed into the exterior threads from a footing end that, when installed, will be proximate to the cortex surface; and, with a tool that is configured to straddle said threaded footing and which tool includes equally spaced ear or tab means that have a lesser thickness than the threaded footing exterior thread height to fit into said longitudinal slots, for turning said threaded footing into or out of said cortex threads.

23. A process as recited in Claim 17, wherein the ligament means is a biologic or prosthetic ligament, or a ligament type device, and may include a stint thererwith.