(12) Ulllted States Patent
`Binder et al.
`
`(10) Patent N0.:
`(45) Date of Patent:
`
`US 8,236,034 B2
`Aug. 7, 2012
`
`US008236034B2
`
`(54) BONE FIXATION PLATE
`
`.
`(75) Inventors: Lawrence J. Binder, Doylestown, PA
`(US); Matthew Hansell, Schwenksville,
`PA (US)
`
`'
`.
`-
`(73) Assignee. Globus Medical, Inc., Audubon, PA
`(Us)
`
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U'S'C' 154(1)) by 1709 days‘
`
`21 A l. N .: 11/097 340
`(
`)
`pp
`0
`’
`
`(22) Flled:
`
`Apr‘ 4’ 2005
`
`6/1996 Michelson
`5,522,899 A
`8/1996 Yapp et a1.
`5,549,612 A
`5,578,034 A 11/1996 E t
`5,626,266 A
`5/l997 Msiflslelson
`5,653,713 A
`8/1997 Michelson
`5,662,300 A
`9/1997 Michelson
`5,681,311 A * 10/1997 Foley et a1. ................. .. 606/283
`5,735,853 A
`4/1998 Olerud
`5,776,199 A
`7/1998 Michelson
`5,797,909 A
`8/1998 Michelson
`6,032,309 A
`3/2000 Michelson
`6,080,155 A
`6/2000 Michelson
`2
`?ic?eiscn
`6,120,503 A
`9/2000 Michelson
`6 136 001 A 10/2000 Michelson
`’
`’
`(Continued)
`
`a
`
`5
`
`10 e SOIl
`
`OTHER PUBLICATIONS
`
`(65)
`
`Prior Publication Data
`
`ISR PCT/US05/l3253,
`
`US 2005/0261690 A1
`
`Nov. 24, 2005
`
`(Continued)
`
`Related U-S- ApplicatiOIl Data
`(63) Continuation-in-part of application No. 10/826,285,
`?l d A .19 2004.
`e on pr
`’
`
`Primary Examiner * Kevin T Truong
`Assistant Examiner* Sameh Boles
`
`(57)
`
`ABSTRACT
`
`(51) IIlt- Cl-
`(2006-01)
`A613 1 7/8 0
`(52) US. Cl. ..................................................... .. 606/289
`(58) Field of Classi?cation Search ................ .. 606/280,
`606/286, 902i906, 289
`See application ?le for complete Search history,
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`4,484,570 A 11/1984 Sutter etal.
`5,135,210 A
`8/1992 Michelson
`5,151,103 A
`9/1992 Tepic etal.
`5,250,061 A 10/1993 Michelson
`5,364,399 A 11/1994 Lowery et a1.
`5,484,437 A
`1/1996 Michelson
`5,505,732 A
`4/1996 Michelson
`5,513,827 A
`5/1996 Michelson
`
`An a aratus for reducin the ro?le of a bone ?xation late
`PP
`g
`P
`P
`While preventing backing out of screws is disclosed. The plate
`has at least two openings though which two screws can pass
`through bony tissue. The apparatus includes at least one sec
`tion of relief and sections of engagement. As the screw is
`tightened, it Will begin to lag the plate to the bone. When the
`screw head interferes with the plate at the interference point,
`there is a slight resistance that insertion forces can overcome.
`When the screw is advanced further, it snaps into the sliding
`?t area and is allowed to move freely. The forces that cause the
`screw to back out from the plate are preferably not strong
`enough to pass the screw head back past the interference
`section. At least one of the two openings is con?gured as an
`elongated slot to allow the screw to translate in the slot. It may
`be desirable to include a set screw to help prevent backout.
`
`17 Claims, 13 Drawing Sheets
`
`Exhibit 2006 Page 1
`
`Globus Medical, Inc. v.
`Bonutti Skeletal Innovations LLC
`Case IPR2015-00417
`Bonutti Skeletal Innovations LLC - Ex. 2006
`
`

`
`US 8,236,034 B2
`Page2
`
`US. PATENT DOCUMENTS
`
`6,730,093 B2
`
`5/2004 Saint Martin
`
`6,139,550 A 10/2000 Michelson 6,142,997 A 11/2000 Michelson
`
`6,152,927 A 11/2000 Farris et al.
`6,159,214 A 12/2000 Michelson
`6,190,388 B1
`2/2001 Michelson et al.
`
`75221 8:121:21 .
`
`252352131 ’ ’
`
`
`4/2001 Michelson
`6,210,412 B1
`5/2001 Brace etal.
`6,235,033 B1
`6/2001 Michelson
`6,241,770 B1
`7/2001 Michelson
`6,257,459 B1
`8/2001 Michelson
`6,269,974 B1
`8/2001 Michelson
`6,270,498 B1
`10/2001 Michelson
`6,299,030 B1
`10/2001 Fllentes
`6,306,139 B1
`11/2001 Michelson
`6,318,602 B1
`2/2002 Michelson
`6,350,283 B1
`‘V2002 M!°he1S°n
`6,364,880 B1
`5/2002 M!°he1S°n
`6,383,186 B1
`6/2002 Mlchelson
`6,398,783 B1
`7/2002 Lyf’ns 6‘ a1~
`6,413,259 B1
`7/2002 M!°he1S°n
`6,416,528 B1
`8/2002 Michelson
`6,428,542 B1
`8/2002 Michelson
`6,436,098 B1
`8/2002 Michelson
`6,440,139 B2
`9/2002 Michelson
`6,447,547 B1
`9/2002 Wigneretal
`6,454,769 B2
`9/2002 Wchelson
`6,454,771 B1
`11/2002 M!°he1S°n
`6,478,823 B1
`12/2002 Mlchelson
`6,500,205 B1
`V2003 Pam
`6,503,250 B2
`2/2003 M!°he1S°n
`6,517,544 B1
`3/2003 Mlchelson
`6,527,776 B1
`3/2003 M!°he1S°n
`6,537,279 B1
`3/2003 M!°he1S°n
`6,537,320 B1
`5/2003 Michelson etal.
`6,561,388 B2
`6/2003 Mlchelson
`6,575,977 B1
`$88; glchelson
`2,235,222 5%
`900% M‘iz?zlm
`6,616,666 B1
`.
`’
`’
`9/2003 Mlchelson
`6,620,163 B1
`9/2003 Weaveretal. .............. ~ 606/281
`6,623,486 B1
`11/2003 “Fakeretal
`6,652,525 B1
`6,652,584 B2 11/2003 Mlchelson
`@2323? 5% 13/588?‘ $281809
`,
`,
`10 e Son
`6,692,503 B2
`2/2004 Foley etal.
`6,695,846 B2
`2/2004 Richelsoph et al.
`6,695,849 B2
`2/2004 Mlchelson
`6,709,458 B2
`3/2004 Mlchelson
`6,712,818 B1
`3/2004 Michelson
`6,716,247 B2
`4/2004 Michelson
`
`3% 6’749’636 B2
`
`6’755’833 B1
`6’770’074 B2
`637933679 B2
`
`$88: 6/2004 Michelson
`
`6/2004 Paul et 31
`@2004 Michelso'n
`9/2004 Michelson
`
`11/2004 Michelson
`B2 6,814,756 B1
`
`400% Michelson
`6875 213 B2
`500% Michelson
`6’890’355 B2
`500% Ball et 31
`6’890’358 B2
`500% Zubok et'al
`6’896’676 B2
`500% Michelson‘
`6’896’680 B2
`7/2005 Michelson
`6’916’320 B2
`@2005 Michelson
`639263718 B1
`8/2005 Michelson
`6,936,050 B2
`8/2005 Michelson
`6936 051 B2
`900% Bray
`639453973 B2
`6,962,606 B2 11/2005 Michelson
`6,966,912 B2 11/2005 Michelson
`6,969,390 B2 11/2005 Michelson
`6,972,019 B2 12/2005 Michelson
`6,972,035 B2 12/2005 Michelson
`6986 772 B2
`V2006 Michelson
`7’008’453 B1
`300% Michelson
`7’011’663 B2
`300% Michelson
`730222137 B2
`400% Michelson
`7,175,624 B2* 2/2007 Konieczynski etal. ...... .. 606/71
`2002/0120273 A1* 8/2002 Needham et a1. ............. .. 606/61
`2002/0133158 A1
`9/2002 Saint Martin
`2002/0147450 A1 10/2002 LeHuec etal.
`2002/0151899 A1* 10/2002 Bailey et a1. .................. .. 606/69
`2003/0149434 A1
`8/2003 Paul
`2003/0187440 A1 10/2003 Richelsoph etal.
`2004/0030338 A1
`2/2004 Paul
`2004/0068319 A1* 4/2004 coiclnio ................... .. 623/17.11
`2004/0097940 A1
`5/2004 Paul
`2004/0133205 A1
`7/2004 Thramann etal.
`2005/0033294 A1
`2/2005 Garden etal.
`2005/0071013 A1
`3/2005 Zuboketal.
`2005/0085812 A1
`4/2005 Shermanetal.
`2005/0149026 A1
`7/2005 Butler et al.
`Zoos/0165400 Al
`7/2005 Fernandez
`2005/0234455 A1 10/2005 Binder etal.
`2005/0261681 A9 11/2005 Branch etal.
`2005/0261690 A1 11/2005 Binder et al.
`OTHER PUBLICATIONS
`writOpnPCT?JS05/13253,
`Haid et al.,“The Cervical Spine Study Group anterior cervical plate
`nomenclature,” Neurosurg. Focus/vol. 12, Jan. 2002.
`
`* cited by examiner
`
`Exhibit 2006 Page 2
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 1 0f 13
`
`US 8,236,034 B2
`
`113_
`
`121
`
`/
`
`_
`
`l
`
`119
`
`FIG. 1
`
`1
`
`//‘1
`
`'
`
`\_117
`
`123
`
`FIG. 2
`
`Exhibit 2006 Page 3
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 2 0f 13
`
`US 8,236,034 B2
`
`Exhibit 2006 Page 4
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 3 0f 13
`
`US 8,236,034 B2
`
`FIG. 5A
`
`FIG. 5B
`
`Exhibit 2006 Page 5
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 4 0f 13
`
`US 8,236,034 B2
`
`FIG. 7
`
`Exhibit 2006 Page 6
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 5 0f 13
`
`US 8,236,034 B2
`
`FIG. 8
`
`FIG. 110A
`
`Exhibit 2006 Page 7
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 6 0f 13
`
`US 8,236,034 B2
`
`FIG. 10B
`
`Exhibit 2006 Page 8
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 7 0f 13
`
`US 8,236,034 B2
`
`Exhibit 2006 Page 9
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 8 0f 13
`
`US 8,236,034 B2
`
`FIG. 13
`
`FIG. 14
`
`Exhibit 2006 Page 10
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 9 0f 13
`
`US 8,236,034 B2
`
`m2 .0;
`
`U2 .UE
`
`Exhibit 2006 Page 11
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 10 0f 13
`
`US 8,236,034 B2
`
`FIG. 16
`
`FIG. 17
`
`Exhibit 2006 Page 12
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 11 0f 13
`
`US 8,236,034 B2
`
`1802
`
`K
`
`1802
`
`1802
`
`1804
`
`1804
`
`Exhibit 2006 Page 13
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 12 0f 13
`
`US 8,236,034 B2
`
`2000
`k /— 2001
`
`Exhibit 2006 Page 14
`
`

`
`US. Patent
`
`Aug. 7, 2012
`
`Sheet 13 0f 13
`
`US 8,236,034 B2
`
`Exhibit 2006 Page 15
`
`

`
`US 8,236,034 B2
`
`1
`BONE FIXATION PLATE
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`The present invention is a continuation-in-part application
`of co-pending US. patent application Ser. No. 10/826,285
`?led Apr. 19, 2004, the entire contents of Which are incorpo
`rated by reference.
`
`FIELD OF THE INVENTION
`
`The present invention relates to a bone ?xation plate used
`to stabilize vertebrae and other bony anatomy. More speci?
`cally, the present invention relates to a cervical plate having a
`minimized pro?le that easily and reliably prevents backout of
`fastening devices.
`
`BACKGROUND OF THE INVENTION
`
`Bones and bony structures are susceptible to a variety of
`Weaknesses that can affect their ability to provide support and
`structure. Weaknesses in bony structures may have many
`causes, including degenerative diseases, tumors, fractures,
`and dislocations. Advances in medicine and engineering have
`provided doctors With a plurality of devices and techniques
`for alleviating or curing these Weaknesses.
`The cervical spine has presented the most challenges for
`doctors, partially due to the small size of the vertebrae and the
`spacing betWeen adjacent vertebrae. Typically, Weaknesses in
`the cervical spine are corrected by using devices that fuse one
`or more vertebrae together. Common devices involve plate
`systems that align and maintain adjacent cervical vertebrae in
`a desired position, With a desired spacing.
`These devices, commonly referred to as bone ?xation plat
`ing systems, typically include one or more plates and screWs
`for aligning and holding vertebrae in a ?xed position With
`respect to one another. Initial devices used stainless steel
`plates and screWs. In order to remain ?xed in place, the screWs
`Were required to pass completely through the vertebrae and
`into the spinal canal. These devices caused many complica
`tions and involved signi?cant risks. To alloW a screW to pass,
`drilling and then tapping of the vertebrae Was required. In the
`process, instruments came Within close proximity of the spi
`nal cord, Which required extreme care on the part of the
`surgeon.
`In addition to the risks of surgically applying bone ?xation
`plates, other complications arose. Commonly, these problems
`involve loosening and failure of the hardWare. TWo common
`failures are the breakage of the plates, and the backing out of
`the screWs into soft tissues of the patient’ s body. The backing
`out of the screWs is typically a result of the screW’s failure to
`achieve a su?icient purchase in the bone, although the strip
`ping of the screWs has also been knoWn to cause this problem.
`Regardless of the cause of the hardWare failures, a surgeon
`must repair or replace the broken parts, Which requires unde
`sirable invasive procedures.
`Advances in material science alloWed engineers to manu
`facture bone ?xation plates out of materials that Would resist
`breakdoWn Within a body. HoWever, the backing out of screWs
`remained a problem. Many solutions Were devised in an
`attempt to prevent this from occurring. One prevalent solution
`involved minimizing the length of the screW in order to pre
`vent screW to plate junction breakage of the screW. HoWever,
`the shortened screW is typically unable to achieve a su?icient
`purchase in the bone. Shortened screWs often provide very
`little holding poWer and inadequate tactile feedback to the
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`2
`surgeon. Tactile feedback to the surgeon is important to signal
`completion of tightening prior to stripping of the screW Within
`the bone.
`An alternate solution involves increasing the length of the
`screWs in order to achieve su?icient purchase to hold the plate
`in place. While the use of longer screWs can provide bicortical
`?xation, this method also has its draWbacks. Primarily, long
`screWs increase the chances of interference With each other
`When they are screWed into bony tissue at an angle. In addi
`tion, many bone ?xation plating systems place bone grafts
`betWeen vertebrae. The bone grafts are eventually supposed
`to spur the groWth of bone betWeen the vertebrae, so that the
`vertebrae become fused together naturally.
`In order for this to occur, the bone ?xation plating needs to
`maintain a desired spacing betWeen the vertebrae, Which is
`?lled by the bone grafts. HoWever, it is common for the bone
`grafts to experience compression, Which separates at least one
`of the adjacent vertebrae from the bone graft. Cervical plates
`that employ long screWs do not alloW for su?icient movement
`of the vertebrae to accommodate the compression of the bone
`graft, because the purchase of the screWs is too great. Thus,
`the vertebrae cannot move and are unable to adjusting to the
`compression of the bone graft.
`Another method of preventing the backing out of screWs
`involves placing a second plate over the screWs. This second
`plate functions to interlock the screWs, preventing them from
`backing out. HoWever, this method of securing screWs often
`becomes bulky, resulting in a large and undesirable pro?le. In
`addition, these con?gurations require carrying out multiple
`steps or using a multi-piece assembly in order to block an
`opening through Which a loose fastener head may pass. For
`instance, the use of a c-ring that can expand as the fastener
`head is inserted requires additional components and assembly
`time to form a plate. Moreover, multi-component designs
`may lose their ability to retain a fastener over time due to
`material failure, relaxation, or the like. Additionally, multi
`component con?gurations may not provide su?icient ability
`to lag the plate to the vertebral body.
`One additional draWback of many designs is that they add
`to the overall height of the plate. It is desirable to maintain a
`loW pro?le design for many reasons, such as to minimize
`irritation to surrounding tissue. For example a plate design
`having a high overall height or a receptacle design that does
`not prevent screW backout may cause a patient to suffer from
`dysphasia. Ultimately, the screW or plate may irritate or Wear
`through neighboring tissue. In addition, a high height plate or
`unretained loose screW in the lumbar spine may be abrasive to
`the aorta or vena cava. Severe abrasion by the plate or screW
`in this instance may puncture the aorta or vena cava and cause
`internal bleeding.
`In addition, many of these plates Were not designed to
`alloW for the locking of all of the screWs, Which left some of
`the screWs susceptible to backout caused by tiny vibrations, or
`micromotion. Some methods attempted to reduce the pro?le
`of the total system by using small parts. HoWever, this led to
`the small parts falling off and getting lost. In addition, the
`smaller parts are fragile and require special instruments in
`order to insert or manipulate them. In addition, because of
`their small size, incorrect placement relative to the axis of the
`plate often causes sharp and jagged shavings to be formed as
`a locking screW contacts an improperly seated bone screW.
`Prior attempts at increasing the screW purchase have
`resulted in risky procedures, or an insuf?cient ability to adapt
`to movement. Attempts and decreasing the pro?le of bone
`?xation plates have resulted in lost parts, or insuf?cient pur
`
`Exhibit 2006 Page 16
`
`

`
`US 8,236,034 B2
`
`3
`chase. A continuing need exists for an apparatus that is able to
`quickly and reliably lock a plurality of screWs into place While
`maintaining a loW pro?le.
`
`SUMMARY OF THE INVENTION
`
`The present invention relates to an apparatus for connect
`ing a plate to a bone. This may be desirable in order to
`immobilize, for example, tWo cervical vertebrae. In one
`embodiment, the present invention comprises at least one
`screW and a plate having at least one opening. As the screW
`passes through the opening and is tightened, it begins to lag
`the plate to the bone. When the screW head interferes With the
`pate at an interference point, there is a slight resistance force
`that insertion forces can easily overcome. When the screW is
`advanced further, it snaps into the sliding ?t area and is
`alloWed to move freely. Forces Which can cause the screW to
`back out of from the plate are preferably not strong enough to
`pass the screW head past the interference section. In some
`embodiments, it may be desirable to use a set screW to aid in
`preventing backout. Alternately, a clamp applied to the head
`of the screW to prevent rotation may be desired.
`In one embodiment, the present invention comprises an
`apparatus for ?xing a plate to bony material, comprising at
`least one opening having a spherical curvature. Also included
`is at least one fastener having a head that interferes With the
`spherical curvature at an interference point. In this embodi
`ment, the head is capable of engaging With and passing the
`interference point to communicate With the spherical curva
`ture.
`In some embodiments, the spherical curvature includes at
`least one engagement area and at least one relief area. The
`tangents to the spherical curvature preferably intersect to
`form an angle. Preferably, the angle of intersection of the
`tangents is betWeen about 1 and about 5 degrees. More pref
`erably, the angle of intersection of the tangents is betWeen
`about 1 and about 3 degrees.
`It is desirable to limit the relief areas in some embodiments
`to prevent a screW from passing through the interference
`point. Accordingly, it is preferred that the relief area com
`prises less than about 40% of the circumference of the spheri
`cal curvature. More preferably, the relief area comprises less
`than about 30% of the circumference of the spherical curva
`ture. In some embodiments, it may be desirable to provide an
`additional opening that is con?gured and dimensioned to
`increase the magnitude of interference at the interference
`point.
`In another embodiment, the present invention comprises an
`apparatus for stabiliZing at least tWo bony structures, com
`prising a plate Where more than one aperture is con?gured and
`adapted to include an interference area. The interference area
`is integrally formed in the plate to prevent a fastener from
`backing out of the interference area.
`In this embodiment, a fastener, such as a screW, is capable
`of engaging With and passing through the interference area.
`The interference area is part of spherical curvature, Which has
`at least one engagement area and at least one relief area.
`Preferably, the tangents to the spherical curvature intersect.
`It is desirable to have the angle of intersection of the tangents
`betWeen about 1 and 5 degrees. In some embodiments, it is
`also preferable to include another opening that is selectively
`positioned to increase the magnitude of interference at the
`interference point. The opening may be con?gured and
`adapted such that it is able to pass a Wedge shaped screW.
`In another embodiment, the present invention comprises an
`apparatus for ?xing a plate to bony material consisting essen
`tially of at least one opening having a spherical curvature. At
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`4
`least one fastener having a head capable of engaging With and
`passing through an interference point of the spherical curva
`ture is also included. In this embodiment, the fastener is
`prevented from backing out of the opening by the interference
`point. In this embodiment, the tangents to the spherical cur
`vature intersect. As described above, another opening may be
`selectively positioned to increase the magnitude of interfer
`ence at the interference point.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a diagram shoWing one embodiment of the bone
`?xation plate according to the present invention;
`FIG. 2 is a diagram shoWing a side vieW of exemplary
`openings according to the present invention;
`FIG. 3A is a diagram shoWing one embodiment of the
`spring loaded plate according to the present invention;
`FIG. 3B is a diagram shoWing an exemplary ramped sur
`face included in the spring loaded plate of FIG. 3A;
`FIGS. 4A and 4B are diagrams shoWing an exemplary
`embodiment of a set screW according to the present invention;
`FIGS. 5A and 5B are diagrams shoWing an exemplary
`embodiment of a bone screW according to the present inven
`tion;
`FIG. 6 is a diagram shoWing another embodiment of the
`bone ?xation plate according to the present invention;
`FIG. 7 is a diagram shoWing one embodiment of the spheri
`cal curvature according to the present invention;
`FIG. 8 is a diagram shoWing the forces exerted by the
`screWs according to the embodiment shoWn in FIG. 6;
`FIG. 9 is a diagram shoWing another embodiment of the
`bone ?xation plate according to the present invention;
`FIGS. 10A and 10B are illustrations of additional embodi
`ments of bone ?xation plates of the present invention;
`FIG. 11 is a diagram shoWing a one embodiment of the
`bone ?xation plate according to the present invention;
`FIG. 12 is a diagram shoWing a drill guide in communica
`tion With a bone ?xation plate of the present invention;
`FIG. 13 is a magni?ed vieW of a drill guide in communi
`cation With a bone ?xation plate of the present invention;
`FIG. 14 is a side vieW of a drill guide in communication
`With a bone ?xation plate of the present invention;
`FIGS. 15A-C are diagrams shoWing an exemplary embodi
`ment of a rigid bone screW according to the present invention;
`FIG. 16 is an illustration of one embodiment of a drill guide
`capable of rotating about an axis of a receptacle or depression
`formed in the plate;
`FIG. 17 is a diagram shoWing one embodiment of the bone
`?xation plate according to the present invention;
`FIG. 18 is a diagram shoWing a side vieW of exemplary
`openings according to the present invention;
`FIG. 19 is a diagram shoWing a side vieW of an elongated
`slot and the translational movement capable by a fastener;
`FIG. 20 is an elevated vieW of another embodiment of a
`plate according to the present invention;
`FIG. 21 is an elevated vieW of one example of one type of
`existing plate con?guration;
`FIG. 22 is an elevated vieW of another embodiment of a
`plate according to the present invention; and
`FIG. 23 is an elevated vieW of another embodiment of a
`plate according to the present invention.
`
`DETAILED DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`The present invention relates to a bone ?xation plate that
`minimiZes the problems associated With prior bone ?xation
`
`Exhibit 2006 Page 17
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`US 8,236,034 B2
`
`5
`plates While maintaining a small pro?le. In one embodiment,
`as a screW is tightened, it Will begin to lag the plate to the bone.
`When the screW head interferes With the plate at an interfer
`ence point, a slight resistance is generated. The insertion
`forces can easily overcome this resistance. When the screW is
`advanced further, it snaps into a sliding ?t area and is alloWed
`to move freely. The forces Which can cause the screW to back
`out from the plate are preferably not strong enough to pass the
`screW head back past the interference section. It may be
`desirable to include a set screW to prevent backout of the
`screWs due to micromotion. In other embodiments, the head
`of the screW may be clamped to prevent rotation, When such
`a restriction on the movement of the screW is desirable.
`The present invention provides a locking mechanism that
`alloWs one or more bone screWs used for attaching a plate to
`vertebrae to be easily and reliably locked in place at the same
`time by a single operation. When fully installed, the locking
`mechanism has a loW pro?le and maintains its ability to
`prevent breakout of screWs due to micromotion. The present
`invention may be used on the anterior or posterior of the
`vertebrae. Although the present invention is described With
`respect to tWo bone ?xation vertebrae, it Will be understood
`that the folloWing embodiments are capable of being used
`With any number of vertebra, in any spinal location.
`Turning noW to the draWings, FIG. 1 shoWs one embodi
`ment of a bone ?xation plate 101 according to the present
`invention. The plate may be secured to tWo vertebrae in order
`to maintain the vertebrae integrally With respect to one
`another in a desired orientation and at a desired spacing from
`one another. Plate 101 includes tWo fastening devices, such as
`screws 103, 105 or the like, Which are operatively communi
`cable With spring loaded plates 107, 109. The plate also
`includes four openings 111, 113, 115, and 117, through Which
`screWs (not shoWn) may be used to fasten the plate 101 to the
`vertebrae.
`The plate 101 and the screWs may be comprised of any
`material, such as a metal, alloy, or any combination of the tWo.
`Preferably, the material used to construct the plate and the
`screWs alloWs the plate 101 to maintain its structural integrity
`While alloWing for a desired amount of resiliency. Further
`more, the material used is preferably bio-compatible and
`capable of Withstanding the conditions of a body over a
`desired period of time. In some embodiments, this is achieved
`by manufacturing the plate 101 and screWs using metals such
`as titanium or stainless steel. Titanium has suf?cient ductility
`to permit a desired amount of curving of the plate 101 to
`conform to the shape of the vertebrae, yet has the strength to
`maintain its structural integrity.
`In the FIG. 1 embodiment, the bone ?xation plate 101
`comprises a center portion 119 and tWo distal portions 121,
`123. Each distal portion 121, 123 may be attached to a dif
`ferent vertebra using fasteners, such as screWs, that pass
`through openings 111, 113, 115, and 117. Because distal
`portions 121, 123 are similar, only the operation of distal
`portion 121 is described in detail.
`FIG. 2 is a diagram shoWing a side vieW of openings 111
`and 113. In one embodiment, each opening has a substantially
`circular shape, as shoWn in FIG. 1. In this embodiment, the
`inner portion of openings 111, 113 have substantially spheri
`cal curvatures. Accordingly, the radius of the inner portion of
`openings 111, 113 decrease in diameter from the top 201 of
`the openings, to the bottom 203 of the openings. Preferably,
`the spherical curvature of the openings 111, 113 may accom
`modate a screW having a spherical head. HoWever, the present
`invention is not limited to spherical curvatures or spherical
`heads. In other embodiments, any complementary head and
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`6
`receptacle may be used. Preferably, the complementary head
`and receptacle are capable of preventing the breakout of the
`screW.
`As shoWn in FIG. 2, the openings 111, 113 are not continu
`ous. It is desirable that the openings 111, 113 comprise only
`a portion of the circumference of the spherical curvature. In
`one embodiment, the remaining portion 205 of the circum
`ference of the spherical curvature of the openings 111, 113 is
`provided by spring loaded plate 107, shoWn in FIG. 1. The
`portion of the circumference of the spherical curvature that is
`completed by spring loaded plate 107 may be varied as
`desired, for example, according to the amount of resistance
`that is desired by the spring loaded plate 107. In one embodi
`ment, the openings 111, 113 comprise at least 60 percent or
`more of the total circumference of the spherical curvature. In
`another embodiment, the openings 111, 113 comprise at least
`70 percent or more of the total circumference of the spherical
`curvature. In yet another embodiment, the openings 111, 113
`comprise at least 80 percent or more of the total circumfer
`ence of the spherical curvature.
`FIG. 3A is a diagram shoWing one embodiment of the
`spring loaded plate 107. In this embodiment, the spring
`loaded plate 107 includes arm 301. When a force causes arm
`301 to be de?ected toWards the body 303 of the spring loaded
`plate 107, potential energy is stored in the arm 301. This
`potential energy causes the arm 301 to generate spring-like
`forces that have a tendency to force it aWay from the body
`3 03, and back to its natural resting position shoWn in FIG. 3A.
`When the de?ection force is removed, the potential energy is
`converted to kinetic energy, and forces the body 303 aWay
`from the arm 301. In other embodiments, the spring loaded
`plate 107 does not have to have a free cantilever load such as
`the arm 301 shoWn in FIG. 3A. For example, it may be
`desirable to use a loop, or the like, to resist movement of the
`spring loaded plate 107.
`The inner portion of plate 107 preferably comprises a
`ramped surface 305. In one embodiment, the ramped surface
`305 is selectively engageable With screW 103, shoWn in FIG.
`1. When the screW 103, is engaged by the ramped surface
`shoWn in FIG. 3B, outWard forces are generated on the screW,
`preventing it from backing out. As the angle of the ramped
`surface increases, the forces that are exerted on the screW 103
`increase. Thus, the angle of the ramped surface may be cho
`sen based on the amount of force that is desired to keep the
`screW 103 from backing out.
`In one embodiment, the angle of the ramp is betWeen about
`5 and 50 degrees. In another embodiment, the angle of the
`ramp is betWeen about 10 and about 30 degrees. In yet another
`embodiment, the angle of the ramp is betWeen about 15 and
`25 degrees.
`The spring loaded plate 107 comprises tWo spherical cur
`vatures 307 and 309. Spherical curvatures 307 and 309 com
`plete the spherical curvatures of openings 111 and 113. Each
`curvature 307, 309 comprises a spherical curvature having a
`radius that decreases from top to bottom, as discussed With
`respect to the curvatures of openings 111 and 113. The spheri
`cal curvatures 307, 309 may comprise any desired percentage
`of the circumference of the total spherical curvature. In one
`embodiment, each curvature 307, 309 may comprise 20 per
`cent or less of the total circumference of the spherical curva
`ture. In another embodiment, each curvature 307, 309 may
`comprise 30 percent or less of the total circumference of the
`spherical curvature. In yet another embodiment, each curva
`ture 307, 309 may comprise 40 percent or less of the total
`circumference of the spherical curvature.
`Spring loaded plate 107 also includes tWo edges 311 and
`313, shoWn in FIG. 3A. Each edge is preferably con?gured
`
`Exhibit 2006 Page 18
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`US 8,236,034 B2
`
`7
`and dimensioned to be engageable With a depression 125 in
`plate 101. In one embodiment, the spring loaded plate 107 is
`positioned Within the depression 125. Depression 125 is con
`?gured and dimensioned such that there is su?icient space for
`plate 107 to move betWeen its compressed and relaxed states,
`described With respect to FIGS. 3A and 3B. In one embodi
`ment, plate 107 is prevented from horizontally exiting depres
`sion 125 by the protrusion formed by openings 111, 113.
`In one embodiment, shoWn in FIGS. 4A and 4B, the screW
`103 may have an angled head 401. It may be desirable for
`screW 103 to have threads along its elongate shaft 403. In
`order to aid in tightening screW 103, it preferably includes a
`projection 405 With a curved surface to aid in gripping the
`screW. The length of the elongate shaft may be varied as
`desired. In one embodiment, the length of the elongate shaft
`is about 5 mm or less. In another embodiment, the length of
`the elongate shaft is about 3 mm or less. In yet another
`embodiment, the length of the elongate shaft is about 1 mm or
`less.
`FIGS. 5A and 5B are diagrams shoWing one embodiment
`of the screW that is used to connect plate 101 to vertebrae.
`ScreW 501 preferably has a spherical head 503 that is selec
`tively engageable With the spherical curvature. An elongate
`shaft 505 is connected to the spherical head 503 to alloW it to
`penetrate bony tissue of the vertebrae. Preferably, the elon
`gate shaft 505 includes threads that aid in ?xing the plate 101
`to a vertebra. As shoWn in FIG. 5B, it is desirable to have a
`hexagonal projection 507 to aid in gripping the screW.
`The length of the elongate shaft 505 may be varied as
`desired. In one embodiment, the length of the elongate shaft
`is about 20 mm or less. In another embodiment, the length of
`the elongate shaft is about 10 mm or less. In yet another
`embodiment, the length of the elongate shaft is about 5 mm or
`less.
`In one embodiment, screW 103 is inserted into a receptacle
`in depression 125. It is desirable to have a threaded receptacle
`such that the screW is capable of being ?xed to the plate 101.
`The screW 103 also passes over plate 107, and prevents it from
`vertically exiting depression 125. The placement of the screW
`receptacle is preferably chosen such that it is engageable With
`the ramped surface 305 of plate 107 When the plate is in its
`relaxed state, Wit