Vertebral body placement and method for spanning a space formed upon removal of a vertebral body Patent Grant Hovda , et al. [Simplify Medical Pty Ltd]

Vertebral body placement and method for spanning a space formed upon removal of a vertebral body

Hovda , et al.

Patent Grant RE47470

U.S. patent number RE47,470 [Application Number 15/191,385] was granted by the patent office on 2019-07-02 for vertebral body placement and method for spanning a space formed upon removal of a vertebral body. This patent grant is currently assigned to Simplify Medical Pty Ltd. The grantee listed for this patent is Simplify Medical Pty Ltd. Invention is credited to Yves Arramon, David Hovda.

United States Patent	RE47,470
Hovda , et al.	July 2, 2019

Vertebral body placement and method for spanning a space formed upon removal of a vertebral body

Abstract

A vertebral body replacement includes first and second end plates, and a compliant connector section between the end plates having one or more helical cuts to provide limited compliance between the end plates. The compliant connector section can be provided in a separate spacer that fits between the end plates or directly in one or more of the end plates. The adjoining end plate surfaces, and/or adjoining surfaces of the spacer, include a rotational interlock to inhibit rotational motion between the surfaces and allow a modular stacking assembly of the vertebral body replacement to accommodate a wide range of patients.

Inventors:

Hovda; David (Mountain View, CA), Arramon; Yves (Sunnyvale, CA)

Applicant:

Name	City	State	Country	Type
Simplify Medical Pty Ltd	Paddington	N/A	AU

Assignee:

Simplify Medical Pty Ltd (AU)

Family ID:

40564282

Appl. No.:

15/191,385

Filed:

June 23, 2016

Related U.S. Patent Documents


	Application Number	Filing Date	Patent Number	Issue Date
	60981665	Oct 22, 2007
Reissue of:	12255737	Oct 22, 2008	8758441	Jun 24, 2014

Current U.S. Class:	1/1
Current CPC Class:	A61F 2/4465 (20130101); A61F 2/30771 (20130101); A61F 2/30771 (20130101); A61F 2/4465 (20130101); A61F 2310/00017 (20130101); A61F 2002/30904 (20130101); A61F 2310/00431 (20130101); A61F 2310/00976 (20130101); A61F 2310/00131 (20130101); A61F 2310/00179 (20130101); A61F 2310/00407 (20130101); A61B 17/86 (20130101); A61F 2002/30787 (20130101); A61F 2250/0032 (20130101); A61F 2002/30772 (20130101); A61F 2310/00407 (20130101); A61F 2310/0088 (20130101); A61F 2310/00604 (20130101); A61F 2002/30889 (20130101); A61F 2002/30884 (20130101); A61F 2002/449 (20130101); A61F 2310/00976 (20130101); A61F 2310/00796 (20130101); A61F 2002/30056 (20130101); A61F 2250/0032 (20130101); A61F 2310/00023 (20130101); A61F 2002/449 (20130101); A61F 2002/30056 (20130101); A61F 2310/00604 (20130101); A61F 2002/30899 (20130101); A61F 2310/0088 (20130101); A61F 2002/30884 (20130101); A61F 2002/30787 (20130101); A61F 2002/30904 (20130101); A61F 2310/00796 (20130101); A61F 2002/30772 (20130101); A61F 2310/00071 (20130101); A61F 2310/00029 (20130101); A61F 2310/00431 (20130101); A61B 17/86 (20130101)
Current International Class:	A61F 2/44 (20060101); A61F 2/30 (20060101); A61B 17/86 (20060101)

References Cited [Referenced By]

U.S. Patent Documents


3867728	February 1975	Stubstad et al.
4309777	January 1982	Patil
4531917	July 1985	Linkow et al.
4566466	January 1986	Ripple et al.
4619660	October 1986	Christiansen et al.
4673407	June 1987	Martin
4759766	July 1988	Buttner-Janz et al.
4759769	July 1988	Hedman et al.
4834757	May 1989	Brantigan
4863477	September 1989	Monson
4904261	February 1990	Dove et al.
4917704	April 1990	Frey et al.
4932969	June 1990	Frey et al.
4946378	August 1990	Hirayama et al.
4997432	March 1991	Keller
5035716	July 1991	Downey
5057108	October 1991	Shetty et al.
5071437	December 1991	Steffee
5122130	June 1992	Keller
5192327	March 1993	Brantigan
5195526	March 1993	Michelson
5258031	November 1993	Salib et al.
5282861	February 1994	Kaplan
5306308	April 1994	Gross et al.
5314477	May 1994	Marnay
5320644	June 1994	Baumgartner
5370697	December 1994	Baumgartner
5394457	February 1995	Leibinger et al.
5401269	March 1995	Buttner-Janz et al.
5415704	May 1995	Davidson
5423816	June 1995	Lin
5458642	October 1995	Beer et al.
5462575	October 1995	Del Corso
5484437	January 1996	Michelson
5489307	February 1996	Kuslich et al.
5505732	April 1996	Michelson
5507816	April 1996	Bullivant
5534030	July 1996	Navarro et al.
5556431	September 1996	Buttner-Janz
5674296	October 1997	Bryan et al.
5676701	October 1997	Yuan et al.
5676702	October 1997	Ratron
5683465	November 1997	Shinn et al.
5702450	December 1997	Bisserie
5709683	January 1998	Bagby
5728159	March 1998	Stroever et al.
5741253	April 1998	Michelson
5776198	July 1998	Rabbe et al.
5782832	July 1998	Larsen et al.
5797909	August 1998	Michelson
5797917	August 1998	Boyd et al.
5824094	October 1998	Serhan et al.
5836948	November 1998	Zucherman et al.
5865846	February 1999	Bryan et al.
5865848	February 1999	Baker
5888226	March 1999	Rogozinski
5895428	April 1999	Berry
5899901	May 1999	Middleton
5899911	May 1999	Carter
5928284	July 1999	Mehdizadeh
5989251	November 1999	Nichols
5989291	November 1999	Ralph et al.
6001130	December 1999	Bryan et al.
6019792	February 2000	Cauthen
6022376	February 2000	Assell et al.
6039761	March 2000	Li et al.
6039763	March 2000	Shelokov
6080155	June 2000	Michelson
6083228	July 2000	Michelson
6086613	July 2000	Camino et al.
6096038	August 2000	Michelson
6106557	August 2000	Robioneck et al.
6132465	October 2000	Ray et al.
6136031	October 2000	Middleton
6139551	October 2000	Michelson et al.
6139579	October 2000	Steffee et al.
6143033	November 2000	Paul et al.
6146421	November 2000	Gordon et al.
6156067	December 2000	Bryan et al.
6159211	December 2000	Boriani et al.
6159214	December 2000	Michelson
6162252	December 2000	Kuras et al.
6174311	January 2001	Branch et al.
6176881	January 2001	Schar et al.
6193757	February 2001	Foley et al.
6224595	May 2001	Michelson
6224607	May 2001	Michelson
6231609	May 2001	Mehdizadeh
6235030	May 2001	Zucherman et al.
6261296	July 2001	Aebi et al.
6264695	July 2001	Stoy
6290726	September 2001	Pope et al.
6296664	October 2001	Middleton
6315797	November 2001	Middleton
6322567	November 2001	Mittelstadt et al.
6336941	January 2002	Subba Rao et al.
6348071	February 2002	Steffee et al.
6368350	April 2002	Erickson et al.
6368351	April 2002	Glenn et al.
6375681	April 2002	Truscott
6375682	April 2002	Fleischmann et al.
6395032	May 2002	Gauchet
6402785	June 2002	Zdeblick et al.
6409766	June 2002	Brett
6413278	July 2002	Marchosky
6416551	July 2002	Keller
6436098	August 2002	Michelson
6440139	August 2002	Michelson
6447544	September 2002	Michelson
6478800	November 2002	Fraser et al.
6517544	February 2003	Michelson
6517580	February 2003	Ramadan et al.
6520967	February 2003	Cauthen
6520996	February 2003	Manasas et al.
6527804	March 2003	Gauchet et al.
6533817	March 2003	Norton et al.
6537279	March 2003	Michelson
6554863	April 2003	Paul et al.
6562047	May 2003	Ralph et al.
6562074	May 2003	Gerbec et al.
6565574	May 2003	Michelson
6579321	June 2003	Gordon et al.
6582466	June 2003	Gauchet
6582468	June 2003	Gauchet
6592624	July 2003	Fraser et al.
6599294	July 2003	Fuss et al.
6607558	August 2003	Kuras
6607559	August 2003	Ralph et al.
6610092	August 2003	Ralph et al.
6623525	September 2003	Ralph et al.
6645248	November 2003	Casutt
6648895	November 2003	Burkus et al.
6652533	November 2003	O'Neil
6660038	December 2003	Boyer, II et al.
6666866	December 2003	Martz et al.
6669731	December 2003	Ralph et al.
6669732	December 2003	Serhan et al.
6673113	January 2004	Ralph et al.
6682562	January 2004	Viart et al.
6689132	February 2004	Biscup
6706068	March 2004	Ferree
6709439	March 2004	Rogers et al.
6712819	March 2004	Zucherman et al.
6712825	March 2004	Aebi et al.
6719794	April 2004	Gerber et al.
6723097	April 2004	Fraser et al.
6726720	April 2004	Ross et al.
6726721	April 2004	Stoy et al.
6733532	May 2004	Gauchet et al.
6740118	May 2004	Eisermann et al.
6740119	May 2004	Ralph et al.
6752832	June 2004	Neumann
6755841	June 2004	Fraser et al.
6764512	July 2004	Keller
6764515	July 2004	Ralph et al.
6770095	August 2004	Grinberg et al.
6790233	September 2004	Brodke et al.
6793678	September 2004	Hawkins
6814737	November 2004	Cauthen
6821298	November 2004	Jackson
6827740	December 2004	Michelson
6830570	December 2004	Frey et al.
6835206	December 2004	Jackson
6846328	January 2005	Cauthen
6852126	February 2005	Ahlgren
6863673	March 2005	Gerbec et al.
6875213	April 2005	Michelson
6896680	May 2005	Michelson
6899735	May 2005	Coates et al.
6936071	August 2005	Marnay et al.
6936132	August 2005	Topolnitsky
6964686	November 2005	Gordon
6966929	November 2005	Mitchell
6966931	November 2005	Huang
6986788	January 2006	Paul et al.
6989011	January 2006	Paul et al.
6994727	February 2006	Khandkar et al.
7011684	March 2006	Eckman
7022138	April 2006	Mashburn
7025787	April 2006	Bryan et al.
7044972	May 2006	Mathys et al.
7044983	May 2006	Cheng
7056344	June 2006	Huppert et al.
7060073	June 2006	Frey et al.
7066958	June 2006	Ferree
7081120	July 2006	Li et al.
7083651	August 2006	Diaz et al.
7087055	August 2006	Lim et al.
7097648	August 2006	Globerman et al.
7115132	October 2006	Errico et al.
7118580	October 2006	Beyersdorff et al.
7147665	December 2006	Bryan et al.
7153325	December 2006	Kim et al.
7169182	January 2007	Errico et al.
7179294	February 2007	Eisermann et al.
7182784	February 2007	Evans et al.
7198644	April 2007	Schultz et al.
7207991	April 2007	Michelson
7214244	May 2007	Zubok et al.
7217291	May 2007	Zucherman et al.
7235082	June 2007	Bartish et al.
7235101	June 2007	Berry et al.
7235103	June 2007	Rivin
7250060	July 2007	Trieu
7255714	August 2007	Malek
7261739	August 2007	Ralph et al.
7267688	September 2007	Ferree
7270679	September 2007	Istephanous et al.
7270682	September 2007	Frigg et al.
7303582	December 2007	Brady
7303583	December 2007	Schar et al.
7309358	December 2007	Berry et al.
7318839	January 2008	Malberg et al.
7326250	February 2008	Beaurain et al.
7331994	February 2008	Gordon
7331995	February 2008	Eisermann et al.
7429270	September 2008	Baumgartner et al.
7442211	October 2008	de Villiers et al.
7452380	November 2008	Zubok et al.
7491241	February 2009	Errico et al.
7494508	February 2009	Zeegers
7517363	April 2009	Rogers et al.
7531001	May 2009	de Villiers et al.
7549995	June 2009	Schultz et al.
7563284	July 2009	Coppes et al.
7563286	July 2009	Gerber et al.
7575598	August 2009	Albert et al.
7578848	August 2009	Albert et al.
7585324	September 2009	Albert et al.
7585326	September 2009	de Villiers et al.
7615078	November 2009	White et al.
7635368	December 2009	Errico et al.
7637913	December 2009	de Villiers et al.
7655045	February 2010	Richelsoph
7708776	May 2010	Blain et al.
7708777	May 2010	O'Neil et al.
7731753	June 2010	Reo et al.
7731754	June 2010	de Villiers et al.
7749272	July 2010	Robie et al.
7763055	July 2010	Foley
7819922	October 2010	Sweeney
8057545	November 2011	Hughes et al.
8092534	January 2012	Eckhardt
8142505	March 2012	Tauber
8298287	October 2012	Moumene
8491637	July 2013	Matthis
8758441	June 2014	Hovda et al.
8771357	July 2014	Biedermann
2001/0016773	August 2001	Serhan et al.
2001/0029377	October 2001	Aebi et al.
2001/0051829	December 2001	Middleton
2002/0022845	February 2002	Zdeblick et al.
2002/0035400	March 2002	Bryan et al.
2002/0045904	April 2002	Fuss et al.
2002/0068936	June 2002	Burkus et al.
2002/0091392	July 2002	Michelson
2002/0116009	August 2002	Fraser et al.
2002/0123753	September 2002	Michelson
2002/0128715	September 2002	Bryan et al.
2002/0165550	November 2002	Frey et al.
2002/0177897	November 2002	Michelson
2002/0198532	December 2002	Michelson
2003/0009224	January 2003	Kuras
2003/0014116	January 2003	Ralph et al.
2003/0023245	January 2003	Ralph et al.
2003/0028249	February 2003	Baccelli et al.
2003/0040746	February 2003	Mitchell et al.
2003/0045884	March 2003	Robie et al.
2003/0045939	March 2003	Casutt
2003/0074076	April 2003	Ferree
2003/0083747	May 2003	Winterbottom et al.
2003/0100951	May 2003	Serhan et al.
2003/0125739	July 2003	Bagga
2003/0130662	July 2003	Michelson
2003/0135277	July 2003	Bryan et al.
2003/0139812	July 2003	Garcia et al.
2003/0187448	October 2003	Michelson
2003/0191536	October 2003	Ferree
2003/0195517	October 2003	Michelson
2003/0195631	October 2003	Ferree
2003/0199982	October 2003	Bryan
2003/0199983	October 2003	Michelson
2003/0204261	October 2003	Eisermann et al.
2003/0208271	November 2003	Kuras
2003/0229358	December 2003	Errico et al.
2003/0233145	December 2003	Landry et al.
2004/0002761	January 2004	Rogers et al.
2004/0024407	February 2004	Ralph
2004/0024410	February 2004	Olson et al.
2004/0030391	February 2004	Ferree
2004/0034426	February 2004	Errico et al.
2004/0054411	March 2004	Kelly et al.
2004/0059318	March 2004	Zhang et al.
2004/0073307	April 2004	Keller
2004/0073311	April 2004	Ferree
2004/0073312	April 2004	Eisermann et al.
2004/0093087	May 2004	Ferree et al.
2004/0097928	May 2004	Zdeblick et al.
2004/0098131	May 2004	Bryan et al.
2004/0117021	June 2004	Biedermann et al.
2004/0143270	July 2004	Zucherman et al.
2004/0143332	July 2004	Krueger et al.
2004/0143334	July 2004	Ferree
2004/0167626	August 2004	Geremakis et al.
2004/0176843	September 2004	Zubok et al.
2004/0186569	September 2004	Berry
2004/0215342	October 2004	Suddaby
2004/0225295	November 2004	Zubok et al.
2004/0225365	November 2004	Eisermann et al.
2004/0230307	November 2004	Eisermann et al.
2004/0236426	November 2004	Ralph et al.
2004/0243238	December 2004	Arin et al.
2004/0254644	December 2004	Taylor
2005/0015094	January 2005	Keller
2005/0015095	January 2005	Keller
2005/0015152	January 2005	Sweeney
2005/0021145	January 2005	de Villiers et al.
2005/0021146	January 2005	de Villiers et al.
2005/0027360	February 2005	Webb et al.
2005/0038515	February 2005	Kunzler
2005/0043800	February 2005	Paul et al.
2005/0085917	April 2005	Marnay et al.
2005/0107881	May 2005	Alleyne et al.
2005/0113842	May 2005	Bertagnoli et al.
2005/0113928	May 2005	Cragg
2005/0143824	June 2005	Richelsoph et al.
2005/0149189	July 2005	Mokhtar et al.
2005/0154463	July 2005	Trieu
2005/0165408	July 2005	Puno et al.
2005/0171604	August 2005	Michalow
2005/0187634	August 2005	Berry
2005/0192586	September 2005	Zucherman et al.
2005/0192670	September 2005	Zubok et al.
2005/0197706	September 2005	Hovorka et al.
2005/0216081	September 2005	Taylor
2005/0216084	September 2005	Fleischmann et al.
2005/0234553	October 2005	Gordon
2005/0251260	November 2005	Gerber et al.
2005/0251261	November 2005	Peterman
2005/0261772	November 2005	Filippi et al.
2005/0267580	December 2005	Suddaby
2005/0267581	December 2005	Marnay et al.
2006/0004377	January 2006	Keller
2006/0004453	January 2006	Bartish et al.
2006/0015183	January 2006	Gilbert et al.
2006/0020342	January 2006	Ferree et al.
2006/0025862	February 2006	Villiers et al.
2006/0030862	February 2006	de Villiers et al.
2006/0036325	February 2006	Paul et al.
2006/0041313	February 2006	Allard et al.
2006/0041314	February 2006	Millard
2006/0052870	March 2006	Feree
2006/0064169	March 2006	Feree et al.
2006/0069439	March 2006	Zucherman et al.
2006/0116768	June 2006	Krueger et al.
2006/0136061	June 2006	Navarro et al.
2006/0142858	June 2006	Colleran
2006/0142862	June 2006	Diaz et al.
2006/0155378	July 2006	Eckman
2006/0167549	July 2006	Mathys et al.
2006/0178744	August 2006	de Villiers et al.
2006/0178746	August 2006	Bartish, Jr. et al.
2006/0195097	August 2006	Evans et al.
2006/0200239	September 2006	Rothman et al.
2006/0200240	September 2006	Rothman et al.
2006/0200242	September 2006	Rothman et al.
2006/0200243	September 2006	Rothman
2006/0224241	October 2006	Butler et al.
2006/0235426	October 2006	Lim et al.
2006/0235525	October 2006	Gil et al.
2006/0235527	October 2006	Buettner-Janz et al.
2006/0241641	October 2006	Albans et al.
2006/0241766	October 2006	Felton et al.
2006/0259144	November 2006	Trieu
2006/0259146	November 2006	Navarro et al.
2006/0265068	November 2006	Schwab
2006/0265077	November 2006	Zwirkoski
2006/0276902	December 2006	Zipnick et al.
2006/0287728	December 2006	Mokhtar et al.
2006/0293752	December 2006	Moumene et al.
2006/0293753	December 2006	Thramann
2006/0293754	December 2006	de Villiers et al.
2007/0010826	January 2007	Rhoda et al.
2007/0021837	January 2007	Ashman et al.
2007/0032875	February 2007	Blacklock et al.
2007/0067035	March 2007	Falahee
2007/0067036	March 2007	Hudgins et al.
2007/0073398	March 2007	Fabian et al.
2007/0093898	April 2007	Schwab et al.
2007/0100453	May 2007	Parsons et al.
2007/0100454	May 2007	Burgess et al.
2007/0100456	May 2007	Dooris et al.
2007/0123903	May 2007	Raymond et al.
2007/0123904	May 2007	Stad et al.
2007/0135923	June 2007	Peterman et al.
2007/0162133	July 2007	Doubler et al.
2007/0168033	July 2007	Kim et al.
2007/0168036	July 2007	Ainsworth et al.
2007/0179615	August 2007	Heinz et al.
2007/0213821	September 2007	Kwak et al.
2007/0233077	October 2007	Khalili
2007/0233247	October 2007	Schwab
2007/0233248	October 2007	Schwab et al.
2007/0233251	October 2007	Abdou
2007/0270956	November 2007	Heinz
2007/0270970	November 2007	Trieu
2007/0282449	December 2007	de Villiers et al.
2007/0299521	December 2007	Glenn et al.
2008/0015698	January 2008	Marino et al.
2008/0015701	January 2008	Garcia et al.
2008/0021557	January 2008	Trieu
2008/0051900	February 2008	de Villiers et al.
2008/0051901	February 2008	de Villiers et al.
2008/0125864	May 2008	de Villiers et al.
2008/0125865	May 2008	Abdelgany
2008/0133011	June 2008	de Villiers et al.
2008/0154301	June 2008	de Villiers et al.
2008/0154305	June 2008	Foley et al.
2008/0154382	June 2008	de Villiers et al.
2008/0161926	July 2008	Melkent et al.
2008/0215155	September 2008	de Villiers et al.
2008/0221696	September 2008	de Villiers et al.
2008/0228274	September 2008	de Villiers et al.
2008/0228277	September 2008	de Villiers et al.
2008/0294259	November 2008	de Villiers et al.
2009/0043391	February 2009	de Villiers et al.
2009/0048674	February 2009	Zubok et al.
2009/0048677	February 2009	McLeod et al.
2009/0076614	March 2009	Arramon
2009/0105833	April 2009	Hovda et al.
2009/0105834	April 2009	Hovda et al.
2009/0105835	April 2009	Hovda et al.
2009/0118836	May 2009	Cordaro
2009/0192617	July 2009	Arramon et al.
2009/0205188	August 2009	de Villiers et al.
2009/0210060	August 2009	de Villiers et al.
2009/0222101	September 2009	de Villiers et al.
2009/0276051	November 2009	Arramon et al.
2009/0326656	December 2009	de Villiers et al.
2010/0004746	January 2010	Arramon
2010/0004748	January 2010	Cordaro
2010/0016972	January 2010	Jansen et al.
2010/0016973	January 2010	de Villiers et al.
2010/0030335	February 2010	Arramon
2010/0049040	February 2010	de Villiers et al.
2010/0069976	March 2010	de Villiers et al.
2010/0076558	March 2010	de Villiers et al.
2010/0087868	April 2010	Barr et al.
2010/0100141	April 2010	de Villiers et al.
2010/0179419	July 2010	de Villiers et al.
2010/0268344	October 2010	de Villiers et al.
2017/0071757	March 2017	Hovda et al.

Foreign Patent Documents


3023353	Apr 1981	DE
3023353	Apr 1981	DE
10035182	Feb 2002	DE
0333990	Sep 1989	EP
0333990	May 1990	EP
0560140	Sep 1993	EP
0560141	Sep 1993	EP
0591712	Apr 1994	EP
0820740	Jan 1998	EP
1142544	Oct 2001	EP
1153582	Nov 2001	EP
1153582	Nov 2001	EP
1250898	Oct 2002	EP
1306064	May 2003	EP
1344493	Sep 2003	EP
1344506	Sep 2003	EP
1344507	Sep 2003	EP
1344508	Sep 2003	EP
1417940	May 2004	EP
1570813	Sep 2005	EP
2803741	Jul 2001	FR
61122859	Jun 1986	JP
S61122859	Jun 1986	JP
63164948	Jul 1988	JP
S63164948	Jul 1988	JP
WO-9920209	Apr 1999	WO
WO-9930651	Jun 1999	WO
WO-0004851	Feb 2000	WO
WO-0035384	Jun 2000	WO
WO-0042954	Jul 2000	WO
WO-0042954	Nov 2000	WO
WO-0101893	Jan 2001	WO
WO-0115637	Mar 2001	WO
WO-0168003	Sep 2001	WO
WO-0211650	Feb 2002	WO
WO-0211650	Sep 2003	WO
WO-2004000170	Dec 2003	WO
WO-2004000171	Dec 2003	WO
WO-2004026187	Apr 2004	WO
WO-2004054477	Jul 2004	WO
WO-2005004756	Jan 2005	WO
WO-2005004756	May 2005	WO
WO-2005053580	Jun 2005	WO
WO-2005072662	Aug 2005	WO
WO-2005112834	Dec 2005	WO
WO-2005112834	May 2006	WO
WO-2006119092	Nov 2006	WO
WO-2006119092	Dec 2006	WO
WO-2007121320	Oct 2007	WO
WO-2007121320	Jun 2008	WO
2003/9312	Nov 2003	ZA
200603171	Sep 2007	ZA

Other References

Chadwick et al., Radiolucent Structural Materials for Medical Applications, Jun. 1, 2001, MDDI, p. 1, http://www.mddionline.com/article/radiolucent-structural-materials-medica- l-applications. cited by examiner .
Office action dated Feb. 8, 2012 for U.S. Appl. No. 12/255,731. cited by applicant .
Office action dated Apr. 18, 2012 for U.S. Appl. No. 12/255,733. cited by applicant .
Office action dated Jun. 7, 2011 for U.S. Appl. No. 12/255,731. cited by applicant .
Office action dated Aug. 26, 2011 for U.S. Appl. No. 12/255,733. cited by applicant .
Office action dated Nov. 23, 2012 for U.S. Appl. No. 12/255,731. cited by applicant .
Office action dated Nov. 28, 2012 for U.S. Appl. No. 12/255,733. cited by applicant .
"ffice Action dated Dec. 19, 2017 for U.S. Appl. No. 15/359,298". cited by applicant .
International search report and written opinion dated Dec. 16, 2008 for PCT/US2008/080800. cited by applicant .
Office action dated May 13, 2011 for U.S. Appl. No. 12/255,737. cited by applicant .
Office action dated Jun. 19, 2012 for U.S. Appl. No. 12/255,737. cited by applicant .
Office action dated Dec. 15, 2011 for U.S. Appl. No. 12/255,737. cited by applicant .
Office action dated Dec. 18, 2012 for U.S. Appl. No. 12/255,737. cited by applicant .
International Search Report and Written Opinion of PCT Application No. PCT/US08/80800, dated Dec. 16, 2008, 11 pages total. cited by applicant .
Buttner-Janz, The Development of.the Artificial Disc. Introduction, pp. 1-18, Library of Congress Catalogue No. 92-75582, ISBN 0-9635430-0-8 (1989). cited by applicant .
Hellier, et al. Wear Studies for Development of an Intervertebral Disc Prosthesis. Spine, vol. 17 No. 6 Supplement pp. 86-96 (1992). cited by applicant .
International search report and written opinion dated Dec. 19, 2008 for PCT/US2008/080798. cited by applicant .
International search report and written opinion dated Dec. 29, 2008 for PCT/US2008/080804. cited by applicant .
Lee, et al. Impact Response of the Intervertebral Disc in a Finite-Element Model. Spine. 2000; 25(19):2431-2439. cited by applicant .
Lehuec, et al. Shock Absorption in Lumber Disc Prosthesis. Journal of Spinal Disorders & Techniques. 2003; 16(4):346-351. cited by applicant .
Office action dated Aug. 14, 2013 for U.S. Appl. No. 12/255,731. cited by applicant.

Primary Examiner: Wehner; Cary E
Attorney, Agent or Firm: Wilson Sonsini Goodrich & Rosati

Claims

What is claimed is:

1. A vertebral body replacement for replacing at least one vertebral body between remaining upper and lower vertebral bodies, the vertebral body replacement comprising: a first end plate having an upper surface configured to engage against a surface of the upper remaining vertebral body, and a lower surface opposite the upper surface spanning the first end plate; a second end plate having a lower surface configured to engage against a surface of the lower remaining vertebral body; a compliant connector section between the first end plate lower surface and the second end plate lower surface, the compliant connector section comprising a plurality of separate stackable spacers each having at least one helical cut configured and arranged to permit limited rotation between the first end plate and the second end plate in an anterior/posterior direction and a lateral direction; and a rotational interlock on the first end plate lower surface and an upper surface of at least one of the spacers, the rotational interlock being configured and arranged to inhibit rotational motion between the first end plate lower surface and the at least one spacer upper surface, wherein the rotational interlock comprises a first raised elongate portion extending in the anterior/posterior direction or the lateral direction on one of the first end plate lower surface or the at least one spacer upper surface and a first complementary elongate recess in the opposite surface.

2. The vertebral body replacement of claim 1, wherein the second end plate includes an upper surface opposite the second end plate lower surface and spanning the second end plate, the compliant connector section located between the second end plate lower and upper surfaces.

3. The vertebral body replacement of claim 2, wherein said rotational interlock is a first rotational interlock, and further comprising a second rotational interlock on the first end plate lower surface and the second end plate upper surface, the second rotational interlock configured and arranged to at least inhibit rotational motion between the first end plate lower surface and the second end plate upper surface.

4. The vertebral body replacement of claim 1, wherein the compliant connector section is configured and arranged to limit motion to less than 10 degrees between said remaining vertebral bodies.

5. The vertebral body replacement of claim 1, wherein the at least one helical cut in each of the separate stackable spacers are oppositely oriented.

6. The vertebral body replacement of claim 1, wherein said rotational interlock is a first rotational interlock, wherein the at least one spacer has a lower surface spanning the at least one spacer, wherein the second end plate has an upper surface spanning the second end plate, and further comprising: a second rotational interlock on the second end plate upper surface and the at least one spacer lower surface, the second rotational interlock configured and arranged to at least inhibit rotational motion between the second end plate upper surface and the at least one spacer lower surface, wherein the second rotational interlock comprises a second raised elongate portion extending in the anterior/posterior direction or the lateral direction on one of the second end plate upper surface or the at least one spacer lower surface and a second complementary elongate recess in the opposite surface.

7. The vertebral body replacement of claim 6, wherein the first and second rotational interlocks are different.

8. The vertebral body replacement of claim 1, further comprising: an adjustment mechanism between the first and second end plates, the adjustment mechanism configured and arranged to selectively move the first and second end plates towards and away from each other.

9. The vertebral body replacement of claim 1, further comprising at least one bone ingrowth hole in at least one of the first and second end plates.

10. The vertebral body replacement of claim 1, wherein each of the first and second end plates comprise a lateral surface, and wherein the at least one bone ingrowth hole extends between said lateral surface and said surface configured to engage against a surface of a remaining vertebral body.

11. The vertebral body replacement of claim 1, wherein the vertebral body replacement is sized and shaped to replace one or more entire vertebral bodies of the human spine.

12. A vertebral body replacement for replacing at least one vertebral body between remaining upper and lower vertebral bodies, the vertebral body replacement comprising: a first end plate having an upper surface configured to engage against a surface of the upper remaining vertebral body, and a lower surface opposite the upper surface spanning the first end plate; a second end plate having a lower surface configured to engage against a surface of the lower remaining vertebral body; a compliant connector section between the first end plate lower surface and the second end plate lower surface, the compliant connector section comprising a plurality of separate stackable spacers each having at least one helical cut configured and arranged to form a continuous spring coil element; and a rotational interlock on the first end plate lower surface and an upper surface of at least one of the spacers, the rotational interlock being configured and arranged to inhibit rotational motion between the first end plate lower surface and the at least one spacer upper surface, wherein the rotational interlock comprises a raised elongate portion extending in the anterior/posterior direction or the lateral direction on one of the first end plate lower surface or the at least one spacer upper surface and a complementary elongate recess in the opposite surface.

13. The vertebral body replacement of claim 12, wherein the vertebral body replacement is sized and shaped to replace one or more entire vertebral bodies of the human spine.

14. A vertebral body replacement for replacing at least one vertebral body between remaining upper and lower vertebral bodies, the vertebral body replacement comprising: a first end plate having an upper surface configured to engage against a surface of the upper remaining vertebral body, and a lower surface opposite the upper surface spanning the first end plate; a second end plate having a lower surface configured to engage against a surface of the lower remaining vertebral body and an upper surface; a compliant connector section between the first end plate lower surface and the second end plate lower surface, the compliant connector section comprising a plurality of separate stackable spacers each having at least one helical cut configured and arranged to form a continuous spring coil element; and a rotational interlock on the second end plate upper surface and a lower surface of at least one of the spacers, the rotational interlock being configured and arranged to inhibit rotational motion between the second end plate upper surface and the at least one spacer lower surface, wherein the rotational interlock comprises a raised elongate portion extending in the anterior/posterior direction or the lateral direction on one of the second end plate upper surface or the at least one spacer lower surface and a complementary elongate recess in the opposite surface.

15. The vertebral body replacement of claim 14, wherein the vertebral body replacement is sized and shaped to replace one or more entire vertebral bodies of the human spine.

16. A vertebral body replacement for replacing at least one vertebral body between remaining upper and lower vertebral bodies, the vertebral body replacement comprising: a first end plate having an upper surface configured to engage against a surface of the upper remaining vertebral body, and a lower surface opposite the upper surface spanning the first end plate; a second end plate having a lower surface configured to engage against a surface of the lower remaining vertebral body and an upper surface opposite the lower surface and spanning the second end plate; a compliant connector section between the first end plate lower surface and the second end plate lower surface, the compliant connector section comprising a plurality of separate stackable spacers each having at least one helical cut configured and arranged to permit limited rotation between the first end plate and the second end plate in an anterior/posterior direction and a lateral direction; and a rotational interlock on the second end plate upper surface and a lower surface of at least one of the spacers, the rotational interlock being configured and arranged to inhibit rotational motion between the second end plate upper surface and the at least one spacer lower surface, wherein the rotational interlock comprises a raised elongate portion extending in the anterior/posterior direction or the lateral direction on one of the second end plate upper surface or the at least one spacer lower surface and a complementary elongate recess in the opposite surface.

17. The vertebral body replacement of claim 16, wherein the compliant connector section is located between the second end plate lower and upper surfaces.

18. The vertebral body replacement of claim 16, wherein the compliant connector section is configured and arranged to limit motion to less than 10 degrees between said remaining vertebral bodies.

19. The vertebral body replacement of claim 16, wherein the at least one helical cut in each of the separate stackable spacers are oppositely oriented.

20. The vertebral body replacement of claim 16, wherein said rotational interlock is a first rotational interlock, and further comprising a second rotational interlock on the first end plate lower surface and the second end plate upper surface, the second rotational interlock configured and arranged to at least inhibit rotational motion between the first end plate lower surface and the second end plate upper surface.

21. The vertebral body replacement of claim 16, further comprising: an adjustment mechanism between the first and second end plates, the adjustment mechanism configured and arranged to selectively move the first and second end plates towards and away from each other.

22. The vertebral body replacement of claim 16, further comprising at least one bone ingrowth hole in at least one of the first and second end plates.

23. The vertebral body replacement of claim 16, wherein each of the first and second end plates comprise a lateral surface, and wherein the at least one bone ingrowth hole extends between said lateral surface and said surface configured to engage against a surface of a remaining vertebral body.

24. The vertebral body replacement of claim 16, wherein the vertebral body replacement is sized and shaped to replace one or more entire vertebral bodies of the human spine.

.Iadd.25. A vertebral body replacement for replacing at least one vertebral body between remaining upper and lower vertebral bodies, the vertebral body replacement comprising: a first end plate having an upper surface configured to engage against a surface of the upper remaining vertebral body and at least one elongated fin on the upper surface configured to enter a slot cut in the upper remaining vertebral body; a second end plate having a lower surface configured to engage against a surface of the lower remaining vertebral body and at least one elongated fin on the lower surface configured to enter a slot cut in the lower remaining vertebral body; a compliant connector section between the first end plate and the second end plate, the compliant connector section comprising a plurality of separate stackable spacers each having at least one helical cut configured and arranged to permit limited rotation between the first end plate and the second end plate in an anterior/posterior direction and a lateral direction, wherein the compliant connector section is configured and arranged to limit motion to less than 10 degrees between said remaining vertebrae..Iaddend.

.Iadd.26. The vertebral body replacement of claim 25, wherein the upper and lower surfaces have less than 10 percent comprising holes..Iaddend.

.Iadd.27. The vertebral body replacement of claim 25, further comprising one or more holes in the first and second end plates configured to receive screws extending through the plates and into the bone..Iaddend.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. .sctn.119 to U.S. Provisional Application No. 60/981,665 filed Oct. 22, 2007, entitled "Method and Spacer Device Spanning Space Formed Upon Removal of an Intervertebral Disc," the full disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to medical devices and methods. More specifically, the invention relates to vertebral body replacements and methods of spanning a space formed upon removal of an intervertebral disc.

Back pain takes an enormous toll on the health and productivity of people around the world. According to the American Academy of Orthopedic Surgeons, approximately 80 percent of Americans will experience back pain at some time in their life. In the year 2000, approximately 26 million visits were made to physicians' offices due to back problems in the United States. On any one day, it is estimated that 5% of the working population in America is disabled by back pain.

One common cause of back pain is injury, degeneration and/or dysfunction of one or more intervertebral discs. Intervertebral discs are the soft tissue structures located between each of the thirty-three vertebral bones that make up the vertebral (spinal) column. Essentially, the discs allow the vertebrae to move relative to one another. The vertebral column and discs are vital anatomical structures, in that they form a central axis that supports the head and torso, allow for movement of the back, and protect the spinal cord, which passes through the vertebrae in proximity to the discs.

Another form of spinal injury involves injury or deformity of the vertebra themselves. When one or more vertebrae is fracture or deformed by tumor or other causes and results in pain and discomfort, surgery is often required. Traditionally, surgical procedures for vertebral replacement have involved removal of the vertebra and fusion of the two vertebrae above and below the missing vertebra. It is necessary to replace the removed vertebra to maintain spacing of adjacent vertebrae. Oftentimes, pins, rods, screws, cages and/or the like are inserted between the vertebrae to act as support structures to hold the vertebrae and graft material in place while they permanently fuse together. These vertebral body replacement procedures generally focus on rigidly fusing the adjacent vertebrae and preventing motion.

However, it would be desirable to achieve immobilization of the vertebrae adjacent a removed vertebral body and maintain spacing between the adjacent vertebrae without the complete rigidity of traditional interbody fusion.

Another problem associated with the typical vertebral body replacement procedure is the subsidence of the cage into the vertebral body. The typical vertebral body replacement cage is formed with a large percentage of open space to allow the bone to grow through and form the bridging bone which immobilizes the vertebrae. However, the large amount of open space means that the load on each segment of the cage is significantly higher than if the cage surface area was larger. This results in the cage subsiding or sinking into the bone over time and allows the space between the vertebrae to collapse.

Therefore, a need exists for improved vertebral body replacement and method for spanning a space and maintaining spacing between two vertebrae after removal of an intervertebral body. Such improved method and intervertebral body replacement would avoid the need for growth of bridging bone between the remaining vertebrae.

BRIEF SUMMARY OF THE INVENTION

Embodiments of the present invention provide a vertebral body replacement with compliance or shock absorption and methods of spanning a space formed upon removal of vertebral body.

In accordance with one of numerous aspects of the present invention, a vertebral body replacement for replacing at least one vertebral body between remaining upper and lower vertebral bodies, the vertebral body replacement comprises a first end plate having an upper surface configured to engage against a surface of the upper remaining vertebral body, and a lower surface opposite the upper surface spanning the first end plate, a second end plate having a lower surface configured to engage against a surface of the lower remaining vertebral body, and a compliant connector section between the first end plate lower surface and the second end plate lower surface, the compliant connector section comprising at least one helical cut configured and arranged to permit limited motion between the first end plate and the second end plate.

In accordance with another aspect of the invention, a method of replacing at least one vertebral body comprises removing said at least one vertebral body between two remaining vertebral bodies, placing a vertebral body replacement between said two remaining vertebral bodies, the vertebral body replacement comprising first and second end plates and a compliant connector section between the first and second end plates, the compliant connector section having at least one helical cut and configured and arranged to limit motion to less than 10 degrees between said remaining vertebral bodies, and maintaining the space between the two remaining vertebral bodies with the vertebral body replacement.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a vertebral body replacement according to one embodiment of the present invention;

FIG. 1A is an exploded, perspective view of the vertebral body replacement of FIG. 1;

FIG. 2 is a perspective view of a vertebral body replacement according to a second exemplary embodiment of the present invention; and

FIG. 3 is a perspective view of a vertebral body replacement according to a third exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Various embodiments of the present invention generally provide for a vertebral body replacement having upper and lower plates or surfaces connected by a central connector portion which provides some limited amount of axial compliance and/or rotational motion between the upper and lower plates or surfaces. The compliant vertebral body replacement according to the present invention can maintain disc height and prevent subsidence with a large surface area while improving outcomes by allowing some limited motion and providing improved fixation. The compliance of the vertebral body replacement also functions to reduce loading on the interface between the bone and vertebral body replacement.

One example of a vertebral body replacement 10 for replacement of a vertebral body and maintaining disc height between two adjacent vertebral discs is shown in FIG. 1. The body 10 includes at least one end plate 20 having a vertebral body contacting surface 24, a second end plate or body end 30 opposite the end plate 20, and a compliant connector or connector section 32 interposed between, or interconnecting, the two ends 20, 30. As will be described below, some limited rotational and axial motion may be provided between the two plates or sections 20, 30 to reduce loading on the interface between the adjacent vertebral bodies and the body 10. According to an exemplary device embodying principles of the present invention, the compliance of the connector 32, as well as some small amount of translation and rotation, is provided by lateral cuts or slots 70 extending into the connector 32. The body 10 when implanted between two vertebrae maintains a desirable space between the two adjacent vertebrae similar to that provided by a natural vertebra.

Although the body 10 has been shown as generally oblong in cross section, other shapes may be used, including circular, oval, elliptical, or rectangular. Although the connector section 32 has been illustrated in FIG. 1 as integral with the end section 30, according to other embodiments, the connector can include one or more separate compliant connectors or spacers in other configurations and at other locations. By way of example, a compliant connector may be the same or substantially the same diameter, size, and shape as the plates, multiple connectors can be arranged in a rectangular pattern, or a hollow cylindrical connector can be used. Further optionally, while the surfaces 24 are illustrated being perpendicular to the vertical axis of the body 10, one or both of the surfaces 24 can be somewhat wedge-shaped, formed with one or two lordosis angles, as well known to those of ordinary skill in the art. The modular design of the upper plate 20 and the lower plate section 30 allows the creation of a complete bodies 10 of different sizes to correspond to the particular space for each patient.

The upper plate 20 and the lower plate or plate section 30, and connector 32, may be constructed from any suitable metal, alloy or combination of metals or alloys, such as but not limited to cobalt chrome alloys, titanium (such as grade 5 titanium), titanium based alloys, tantalum, nickel titanium alloys, stainless steel, and/or the like. They may also be formed of ceramics, biologically compatible polymers including PEEK, UHMWPE (ultra high molecular weight polyethylene) or fiber reinforced polymers. However, when polymer is used for the body 10, the contacting surfaces 24 may be coated or otherwise covered with metal for fixation. The upper plate 20 and the lower plate or plate section 30, and connector 32, may be formed of a one piece construction or may be formed of more than one piece, such as different materials coupled together. When the body 10 is formed of multiple materials, these materials are fixed together to form a unitary one piece spacer without separately moving parts.

Different materials may be used for different parts of the body 10 to optimize imaging characteristics. For example, the upper plate 20 and the lower plate or plate section 30 may be formed of titanium, while the connector 32 is formed of cobalt chromium alloy for improved imaging of the plates. Cobalt chrome molybdenum alloys, when used for the plates 20, 30 may be treated with aluminum oxide blasting followed by a titanium plasma spray to improve bone integration. Other materials and coatings can also be used such as titanium coated with titanium nitride, aluminum oxide blasting, HA (hydroxylapatite) coating, micro HA coating, and/or bone integration promoting coatings. Any other suitable metals or combinations of metals may be used as well as ceramic or polymer materials, and combinations thereof. Any suitable technique may be used to couple materials together, such as snap fitting, slip fitting, lamination, interference fitting, use of adhesives, welding and/or the like.

In some embodiments, the outer surface 24 is planar. Oftentimes, the outer surface 24 will include one or more surface features and/or materials to enhance attachment of the body 10 to vertebral bone. For example, as shown in FIG. 1, the outer surface 24 may be machined to have serrations 40 or other surface features for promoting adhesion of the plates 20, 30 to a vertebra. In the embodiment shown, the serrations 40 are pyramid shaped serrations extending in mutually orthogonal directions, but other geometries such as teeth, grooves, ridges, pins, barbs or the like would also be useful. When the bone integration structures are ridges, teeth, barbs or similar structures, they may be angled to ease insertion and prevent migration. These bone integration structures can be used to precisely cut the bone during implantation to cause bleeding bone and encourage bone integration. Additionally, the outer surface 24 may be provided with a rough microfinish formed by blasting with aluminum oxide microparticles or the like to improve bone integration. In some embodiments, the outer surface may also be titanium plasma sprayed or HA coated to further enhance attachment of the outer surface 24 to vertebral bone.

The outer surfaces 24 may also carry one or more upstanding fins 50, 52 which also extend laterally in an anterior-posterior direction. The fins 50, 52 are configured to be placed in slots in the vertebral bodies. Preferably, the fins 50, 52 each have a height greater than a width and have a lateral length greater than the height. In one embodiment, the fins 50, 52 are pierced by transverse holes 54 for bone ingrowth. The transverse holes 54 may be formed in any shape and may extend partially or all the way through the fins 50, 52. In alternative embodiments, the fins 50, 52 may be rotated away from the anterior-posterior axis, such as in a lateral-lateral orientation, a posterolateral-anterolateral orientation, or the like.

The fins 50, 52 provide improved attachment to the bone and prevent rotation of the plates 20, 30 in the bone. In some embodiments, the fins 50, 52 may extend from the surface 24 at an angle other than 90.degree.. For example, on one or more of the plates 20, 22 where multiple fins 52 are attached to the surface 24, the fins may be canted away from one another with the bases slightly closer together than their edges at an angle such as about 80-88 degrees. The fins 50, 52 may have any other suitable configuration including various numbers angles and curvatures, in various embodiments. In some embodiments, the fins 50, 52 may be omitted altogether. The embodiment of FIG. 1 illustrates a combination of one plate with a single fin 50 and another plate with a double fin 52. This arrangement is useful for double level disc replacements and utilizes offset slots in the vertebral body to prevent the rare occurrence of vertebral body splitting by avoiding cuts to the vertebral body in the same plane for multi-level implants. The combination of the single fin 50 and double fin 52 can also assist the surgeon in placement of the spacer in the correct orientation.

The body 10 has been shown with the fins 50, 52 as the primary fixation feature; however, the fins may also be augmented or replaced with one or more screws extending through the plates and into the bone. For example in the body 10 of FIG. 1, the upper fin 50 may be augmented or replaced with one or more screws (not illustrated) while the two lower fins 52 remain. The plates 20, 30 can be provided with one or a series of holes 60 to allow screws to be inserted at different locations at the option of the surgeon. However, the holes 60 should not be of such size or number that the coverage of the plate 20, 30 is decreased to such an extent that subsidence occurs. Alternately, the screws can pass laterally through one or more of the holes in the fins. When one or more screws are provided, they may incorporate a locking feature to prevent the screws from backing out. The screws may also be provided with a bone integration coating.

Some limited holes may also be provided in the plate to allow bone ingrowth. However, if the outer surfaces 24 have holes therein, the holes advantageously cover less than 40 percent of the outer surface 24 which contacts the bone to prevent subsidence of the plates into the vertebral bodies. Preferably the holes will cover less than 25 percent, and more preferably less than 10 percent of the outer bone contacting surfaces. At the option of the surgeon, when the small holes are present in the plates 20, 30, bone graft can be placed in the holes to allow bone to grow through the plates. The embodiments illustrated in FIGS. 1-3 also illustrate the optional inclusion of countersunk screw holes 60 extending between a lateral surface of the plates 20, 30 and the end surfaces 24, in which bone screws may optionally be inserted to further stabilize the body 10. The holes 60 can alternatively extend vertically through the end plates, or the end plates can include combinations of vertical and angled holes.

The vertebral body replacement 10 shown herein is configured for placement in the vertebral column from an anterior approach. It should be understood that other approaches can be used, and the particular shape of the vertebral body replacement would be modified depending on the approach. For example, for a lateral approach, the vertebral body replacement may be formed in a more elongated, kidney bean, or banana shape with a transversely oriented fin.

As shown in FIG. 1, the vertebral body replacement 10 is provided with shock absorption or some other limited motion between the two plates 20, 30 by providing a compliant connector 32. The limited motion provided by the compliant connector 32 is designed to reduce forces on the interface between the outer surfaces 24 and the bone to improve long term fixation of the spacer. The compliance of the connector 32 allows motion between the vertebral bodies to be accommodated by the compliance in the body 10 rather than causing one or both of the vertebral bodies to pull away from the plates 20, 30. The compliant connector 32 provides limited relative motion between the plates, which may include compliance in a vertical direction of up to about 6 mm, rotation in an anterior/posterior direction, lateral direction, or axial rotation of less than about 10 degrees, and/or translation of up to about 1 mm.

In the vertebral body replacement 10 of FIG. 1, the compliance, as well as some small amount of translation and rotation, is provided by the cuts or slots 70 extending into the connector 32. In the embodiment of FIG. 1, the slots 70 are spiral slots, however, other shaped slots may also be used. The compliant connector 32 is advantageously formed as a unitary member with at least one lateral cut or slot 70 positioned between the upper and lower plates 20, 30, permitting the plates to move resiliently toward and away from each other. The replacement 10 can also be formed as multiple parts where different properties are desired from the different parts, such as different radiopacities, different strengths, or different flexibility properties and for flexibility in creating the size and configuration of spacer suited to the patient. The lateral cuts 70 in the connector 32 allow the connector to function as a compliant member without affecting the function of the upper and lower plates of the body 10.

FIG. 2 illustrates an alternative embodiment of a body 10 having multiple parts including end plates 20, 30 and spacers 90. The spacers 90 include lateral cuts 70 in place of the spiral cuts of FIG. 1. The material remaining after the cuts 70 are made is called a column. A shallow cut, that is, one that extends laterally into the connector a relatively small distance, and a large column provides a stiffer spacer, while a deeper cut and smaller column provides a more compliant spacer. In the embodiment shown in FIG. 2, the cuts 70 are at least 60% of the way through the spacer width or diameter, and preferably at least 75% of the way through the connector width.

Optionally, a variable stiffness shock absorbing connector 32 (FIG. 1) or spacer 90 (FIG. 2) can be constructed with lateral cuts 70 with tapering widths. For cuts with such tapering widths, the cut 70 is smallest where the cut terminates adjacent the column and is largest at the edge of the connector 32 furthest from the column. In this version, each of the lateral cuts 70 causes the connector 32 to act as a non linear spring providing progressively stiffer behavior upon larger compression. This is due to the fact that progressively more material on the sides of the cuts 70 is in contact as the connector 32 or spacer 90 is compressed. The non-linear spring can be incorporated in any of the other embodiments described herein to provide a softer stop to the compliant action of the core. The tapered width cuts 70 can provide the additional benefit of providing a flushing action during operation that moves any accumulated material out of the cuts.

The cuts 70 also advantageously include a stress relief 74 at the end of the cuts which increases the fatigue life of the device by reducing the stress concentration at the ends of the slots.

In the exemplary embodiments illustrated herein, a shock absorbing connector 32 includes either one or more planar cuts 70 (FIG. 2), or alternatively one or more spiral or helical cuts 70 (FIG. 1) to form one or more continuous spring coil elements 72 which provide compliance to the connector. Although the spiral cut connector 32 is illustrated in FIG. 1 with two spiral cuts, only one, or three or more spiral cuts may also be employed. For example, two or more spiral cuts 70 arranged in opposite directions can be formed in the connector 32, as illustrated in FIG. 1. Furthermore, when more than one spiral cut 70 is provided, the cuts can optionally be nested one inside the other (not illustrated), as in the manner of a multi-start thread, and/or can include combinations of both nested and adjacent cuts (such as those illustrated in FIGS. 1-2). The compression of a spiral cut connector 70 can result in some small amount of relative rotation between the upper and lower surfaces 20, 30. In cases where it is desirable to eliminate this rotation, a connector 32 having multiple spiral cuts in opposite directions can be used. For example, a connector 32 can be formed with a first spiral cut 70 at a top of the connector in a first direction and a second spiral cut 70 at a bottom of the core in an opposite second direction. The first and second spiral cuts can offset rotation of each other resulting in a non rotating compliant connector. The double spiral embodiment of the connector is also more stable in shear than the single coil. Furthermore, coils 74 provide significantly more surface area between the adjoining surfaces of the cuts 70 than do planar cuts, which can be advantageous to allow limited rotational motion. The spiral cuts 70 can be made parallel to the end surfaces of the body 10 or can be angled, as in a cone shape. When the spiral cuts 70 are angled to form a cone shaped spring the cone shaped surfaces can limit the translational movement of the spring.

In each of the shock absorbing connectors described herein, the interconnected sections within the connector and the plate(s) are designed for minimal or no motion between contacting parts to prevent particulate generation. However, since the plates and connectors are made entirely of hard materials such as metals, some minimal rubbing contact may be accommodated. In the exemplary embodiments illustrated in figures herein, a rotational interlock 80 is provided between the lower surface of the end plate 20 and the adjoining upper surface of the connector section 32 of the end plate 30. With reference to FIG. 2, the exemplary interlock 80 includes complementary portions 82, 84, formed on the adjoining faces of the end plate 20 and the connector section 32, in the exemplary body 10, taking the shape of simple raised portions or ribs 84 which mate with correspondingly sized and shaped recesses 82. The rotational interlock 80 is not limited to the particular shapes or orientations illustrated in the drawing figures, and can take any shape or orientation which resists, and advantageously prevents, the plate 20 and the connector section 32 from rotating relative to each other. The rotational interlock 80 on the top and bottom surface of a spacer 90 can be different to allow the complete body 10 to be assembled only in a particular desired configuration.

Further optionally, as illustrated in FIG. 1A, the body 10 can include one or more blind cavities 86 extending vertically through the connector section 32, which provides the interior side of the spiral cut 70. The blind cavities 86 can also vary in cross sectional size and shape to tailor the rigidity of the connector section 32 in different directions. More specifically, the cavity or cavities 86, only one of which is illustrated in FIG. 1A, when left hollow, provides a less rigid connector 32. To increase the rigidity of the connector section 32, other material can be used to partially or completely fill the cavity 86, such as pins or rods (not illustrated) inserted in the cavity.

When implanted between vertebrae, the shock absorbing connector 32 can resiliently absorb shocks transmitted vertically between upper and lower vertebrae of the patient's spinal column. This shock absorption is related to the material properties, design, and dimensions of the connector. In general, an increased number and width of the cuts 70 will increase absorption of shocks, with more elastic, or springy compression between the vertebrae.

Preferably the connector 32 is made of metal such as titanium, cobalt chromium alloy, stainless steel, tantalum, nickel titanium or a combination thereof. These materials also can be designed to provide a device which is deformable in the elastic region of the stress/strain curve and will not plastically deform during compression.

In the embodiments illustrated herein, the number, pitch, lead, lead angle, handedness, and total vertical length of each of the spiral cuts or slots 70, as well as the combination of multiple cuts if provided, can be varied to change the amount of compliance of the connector 32. When a load is applied to the upper and lower plates 20, 30, the connector 32 will compress with each of the cuts 70 closing and the total amount of compression possible depending on the number, arrangement, and height of the cuts. The cuts 70 form spiral coils 74 between the ends of the cut, which function like springs to allow the connector 32 to be compressed. The cuts 70 may be modified to be non-uniform to provide preferential deflection in one or more bending directions. Preferential deflection is useful to provide increased anterior-posterior compliance and less lateral compliance, or the other way around.

According to one embodiment of the invention, the cuts 70 in the shock absorbing connector 32 according to any of the embodiments described herein may be manufactured by wire EDM (electrical discharge machining), molding, laser cutting, or the like. A number of cuts 70 can vary from 1 to about 50, preferably about 6 to about 20, for a vertebral body replacement. A width of the lateral cuts 70 in the direction of the height of the body 10 is about 0.01 mm to about 2 mm, preferably about 0.05 to about 1 mm.

In one embodiment of the present invention, for a cervical application, the maximum deformation of the shock absorbing body is about 0.5 to about 4 mm, and is preferably about 1 to about 2 mm. For a lumbar application, the maximum deformation of the shock absorbing body is about 1 to about 6 mm, and is preferably about 1 to about 3 mm.

Although motion between the plates 20, 30 of the body 10 has been described herein as provided by cuts 70, it should be understood that this motion can be provided in a number of other known manners, such as use of resilient materials, or movable joints as long as the motion is limited to the small amount of motion allowable in a patient requiring a fusion procedure including compliance or vertical motion between the plates of up to about 6 mm, rotation between the plates of less than 10 degrees, and translation between the plates of up to about 1 mm.

The body 10 can be provided in different sizes, with different plate sizes, angles between plates, lordosis angles, and heights for different patients or applications. In addition, the shock absorbing connector section 32 can be provided in different compliances for different patients. In addition, the compliance and/or height of the body 10 can be adjustable, such as by rotating an adjustment screw before or after implantation, and/or bonding portions of one or more of the portions of a coil 74. The body 10 preferably is sized to provide substantial coverage of the vertebral surfaces. For example, in an anterior procedure, the plates 20, 30 are preferably sized to cover at least 50 percent of the vertebral surface. In posterior or lateral procedures, the coverage of the vertebral surface may be somewhat smaller due to the small size of the access area, i.e., the posterior or lateral spacers may cover about 40 percent or more of the vertebral surface with a one or two part spacer.

Turning now to FIG. 2, a second exemplary embodiment of a body 10, adhering to principles of the present invention, is illustrated. In contrast to the embodiment illustrated in FIGS. 1 and 1A, the body 10 illustrated in FIG. 2 includes one or more separate compliant connector spacers 90 positioned between plates 20, 30, rather than a connector section 32 of a plate 30. Each of the spacers 90 includes one or more cuts 70, which can be either planar cuts or forming one or more coils, as described above with reference to the embodiment of FIGS. 1 and 1A. The adjoining surfaces of the plates 20, 30 and the spacers 90 are also provided with rotational interlocks 80, as described herein; while FIG. 2 suggests that the interlocks 80 are the same, differently configured interlocks can alternatively be provided for different non-adjoining surfaces, for example to prevent the spacers 90 from being assembled in a way other than that designed for a body 10 configured for the particular patient. By way of non-limiting example, a first rotational interlock, formed of rectangular ribs and recesses on adjoining surfaces of the end plates and/or the spacers, as illustrated in FIG. 1A, can be provided on the adjoining surfaces of the plate 20 and the adjacent first spacer 90; a second rotational interlock, formed of vertically oriented cylindrical pins, can be provided on the opposite face of the first spacer 90 and the adjoining surface of the adjacent spacer or plate 30. Because the two interlocks 80 are incompatible and do not mate, there is only a single configuration of the pieces that will permit them to be assembled into a body 10.

FIG. 3 illustrates a third exemplary embodiment of a body 10, adhering to principles of the present invention. In addition to the features previously described with reference to FIGS. 1-2, the embodiment illustrated in FIG. 3 includes a vertical adjustment mechanism 100 for fine tuning of the vertical size of the body 10, either prior to or after implantation of body 10 into a patient. While numerous configurations of the adjustment mechanism 100 can be provided, one exemplary embodiment includes a threaded post or tube 102 extending from either an upper surface 106 of the end plate 30 or a lower surface 104 of the section 32, which mates with a correspondingly configured and threaded hole or post in the other of the end plate 30 and section 32. Rotation of the post 102 causes the two portions of the body 10 to move toward or away from each other, and thus decreases or increases the vertical size of the body 10, respectively. According to one version of the adjustable height vertebral body replacement an adjustment mechanism with oppositely threaded ends is inserted in the upper and lower parts 104, 106 and is adjustable after positioning in the patient.

According to one exemplary method adhering to principles of the present invention, a patient in need of a vertebral body replacement is prepped and surgical access is made to the particular vertebral body to be removed. Access to the surgical site is generally made anteriorly through the abdominal cavity for a lumbar procedure. One or more target vertebral body or bodies is removed in one of numerous manners known to those of ordinary skill in the art, between upper and lower remaining vertebral bodies in the patient's spine, and a vertebral body replacement 10, embodying principles of the present invention, is selected based on the measurement of the spacing for proper spinal alignment. The vertebral body replacement 10 is assembled and implanted in the space created by removal of the original vertebral body or bodies. Optionally, one or more spacers 90 are assembled into the body 10, prior to installation of the body 10 into the patient, and/or the vertical length of the body 10 is adjusted to better fit in the space. Further optionally, when the body 10 includes one or more cavities 86, additional material is inserted into the cavity, prior to implantation of the body, to tailor the rigidity of the body 10, or for other purposes.

While the exemplary embodiments have been described in some detail, by way of example and for clarity of understanding, those of skill in the art will recognize that a variety of modifications, adaptations, and changes may be employed. Hence, the scope of the present invention should be limited solely by the appended claims.

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References

mddionline.com/article/radiolucent-structural-materials-medical-applications

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