Not Applicable.
1. The Field of the Invention
The present invention relates to polyaxial and fixed bone screws and components thereof that can be used for stabilizing adjacent vertebrae of the spine or other adjacent bones.
2. The Relevant Technology
Polyaxial screws are commonly used in spinal operations for adjusting or stabilizing adjacent vertebrae. For example, in one conventional procedure a first polyaxial screw is screwed into a first vertebra while a second polyaxial screw is screwed into an adjacent second vertebra. A stabilizing rod is then secured between the polyaxial screws so as to fix the adjacent vertebrae relative to each other. Polyaxial screws can be positioned on each side of each vertebra and can be positioned in any number of consecutive vertebrae with one or more rods extending between the different polyaxial screws.
A conventional polyaxial screw comprises a bone screw having a collar pivotably mounted on the end thereof. The bone screw is inserted into the bone and the stabilizing rod is received within the collar and secured therein. To be strong enough to handle the stresses placed upon it, the polyaxial screw is made of titanium or some other biocompatible metal. Being made of metal allows the doctor to view the bone screw using X-ray photographs during and after implantation.
However, because the bone screws are made of metal, the screws block X-rays passing through the body, in effect obscuring adjacent bone and other X-ray viewable internal structures surrounding the area and thereby preventing the surgeon from viewing those structures on an X-ray photograph. This can limit a surgeon's ability to ensure proper placement of the bone screw and diagnose and treat problems that arise near the location of the bone screw after the bone screw has been implanted.
Accordingly, what is needed are polyaxial and fixed bone screws that overcome some or all of the above disadvantages.
Various embodiments of the present invention will now be discussed with reference to the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope.
Depicted in
As depicted in
As shown in
Turning to
Attachment member 126 centrally projects from end face 132 of shaft body 113. As discussed below in greater detail, attachment member 126 is used to engage and secure head 110 to shaft 108. As such, attachment member 126 is sized and shaped so as to fit within a complementary attachment recess 128 disposed on head 110 (see
In the depicted embodiment, side wall 130 of attachment member 126 comprises a substantially cylindrical portion 135 and a flat 136. Flat 136 in effect removes a portion of the rounded side of the cylinder portion 135. In an alternative embodiment side wall 130 is formed without a flat. Other cross sectional attachment shapes can alternatively be used. For example, side wall 130 of attachment member 126 can be oval, polygonal, star shaped, irregular, or the like. Other shapes are also possible.
Continuing with
Shaft 108 can be comprised of a radiolucent material that will allow viewing of adjacent bone or other internal structures on an X-ray photograph that are in the viewing path of shaft 108. Using radiolucent material for the shaft 108 will also minimize scattering caused by commonly used metallic or other radiopaque shafts in X-Rays, CAT scans, MRI's, and other types of imaging systems. One example of a radiolucent material that can be used in shaft 108 is a biocompatible fiber and adhesive matrix, such as a carbon fiber epoxy matrix. In such a matrix, biocompatible fibers are impregnated with an epoxy resin, molten plastic, or other type of adhesive, then wound about a rod or other object to create many layers wound on top of each other. The fibers can be wound one fiber at a time or multiple fibers at a time in a fiber bundle or tow. Alternatively, the fibers can be included in a sheet and the sheet wound about the rod. Various winding patterns can also be used. Many types of biocompatible fibers and adhesives can be used. Methods of manufacturing the shaft 108 and other portions of the bone screw 102 are discussed in more detail below.
In one embodiment, the fibers comprise a continuous high strength, PAN based carbon fiber, 34-700, 12 k (tow), “unsized” and approved for permanent implant. By “unsized,” it is meant that the fibers have not been coated with a material to improve adhesion of the resin or adhesive. Other types or sizes of biocompatible fibers can also be used, such as fiberglass, kevlar or other biocompatible fibers.
Examples of biocompatible epoxies that can be used to bond the fibers include the Master Bond Inc. epoxies EP42HT-2 and EP45HT MED and the Epotek epoxies 301-2 and 375. Other epoxies that are implantable, biocompatible, sterilizable, and have the desired strength properties can also be used. Examples of biocompatible resins that can be used to bond the fibers include polyetheretherketone (PEEK), polyethylene, polyurethane, polyimide, and polyamide. Other materials can alternatively be used.
To aid in implantation of the bone screw, an encircling marker can be included within shaft 108 that is spaced apart from first passageway 140. For example, as shown in
In another embodiment, a thin ring layer can be affixed or otherwise placed on exterior surface 122 in place of or in addition to ring 147. For example, as shown in
In one embodiment, positioning ring 147 and/or ring layer 148 are positioned about midway between proximal end 114 and distal end 116. In other embodiments, positioning ring 147 and/or ring layer 148 are positioned substantially closer to proximal end 114 and in still other embodiments substantially closer to distal end 116. In other embodiments it is appreciated that two or more positioning rings 147 and/or ring layers 148 can be positioned along shaft 108 at spaced apart locations. Furthermore, in alternative embodiments the marker need not be a ring but can be any desired shape and at any position or orientation that will produce a desired marking.
Returning to
Turning to
An engagement slot 164 is formed on head 110. Engagement slot 164 comprises a pair of opposing side walls 166 and 168 that are generally disposed in parallel planes and extend to a rounded floor 170 and a back wall 172. Back wall 172 typically intersects with floor 170 at a right angle while back wall 172 is disposed generally parallel to central longitudinal axis 162 at a distance spaced apart therefrom. In alternative embodiments, floor 170 need not be rounded but can be flat, V-shaped, or have other configurations. It is appreciated that engagement slot 164 can have a variety of different configurations and merely needs to be sized, shaped, and oriented to permit the desired pivoting of collar 104 and rotation of bone screw 102 as will be discussed below in greater detail.
Turning to
Returning to
Head 110 can comprise a radiolucent material and/or a radiopaque material. In one embodiment, head 110 comprises a radiopaque metal, such as titanium, stainless steel, tungsten, alloys, or other biocompatible metals. In one embodiment, head 110 comprises the same radiolucent material as shaft 113.
Returning to
Core 112 comprises a head portion 204 at proximal end 200 and a shaft portion 206 at distal end 202. Head portion 204 of core 112 is shaped to fit within second passageway 182 of head 110 and shaft portion 206 is shaped to fit within first passageway 140 of shaft 108. For example, in the embodiment depicted, shaft portion 206 has a substantially circular cross section (see
Various geometric cross sectional shapes can alternatively be used for the head portion 204 and/or the shaft portion 206 of core 112. For example,
In one embodiment, core 112 has a maximum diameter that is less than about 3 millimeters and more commonly less than about 2 millimeters. Other diameters or widths can also be used.
Core 112 is typically comprised of a radiopaque material. Examples of such materials that can be used in core 112 are titanium, stainless steel, tungsten, alloys, or other biocompatible metals. In some embodiments, core 112 is comprised of the same material as head 110. One advantage of using a radiopaque material in core 112 while using a radiolucent material in shaft 108 is that only the thin core 112 will be seen on an X-ray during and after implantation of bone screw 102. This aids the surgeon in positioning bone screw 102 when implanting bone screw 102, yet allows other internal body structures to be viewed by X-ray during and after bone screw 102 implantation. In an alternative embodiment, however, core 112 can be comprised of a radiolucent material, such as those previously discussed with regard to shaft 108.
Turning to
Side wall 220 is formed having a pair of channels 234 and 236 that are disposed on opposing sides of side wall 220 and that transversely extend through side wall 220. In the embodiment depicted, channels 234 and 236 each have a substantially U-shaped configuration. Each channel 234 and 236 has an open mouth 238 that extends through end face 230 and an opposing floor 240 that is rounded. Each channel 234 and 236 is configured so that stabilizing rod 107 (
As shown in
Shoulder 248 has a tapered interior surface that forms an annular seat 250. As will be discussed below in greater detail, bottom portion 150 of head 110 of bone screw 102 (
As also depicted in
Returning to
Radially outwardly projecting from side wall 272 of locking screw 270 so as to encircle locking screw 270 is a helical thread 282. Recessed on top surface 274 is a polygonal socket 284 adapted to receive a driver. Threads 282 of locking screw 270 are configured to threadedly engage with internal threads 233 of collar 104 (
Collar 104 and fastener 106 are simply one example of a collar and fastener that can be used with bone screw 102 described herein. Other collars and associated fasteners can alternatively be used, such as the collars and fasteners described in U.S. patent application Ser. No. 11/863,133, filed Sep. 27, 2007, which is incorporated herein by specific reference.
Methods of manufacturing and assembling the bone screw 102 and polyaxial screw 100 will now be discussed.
To manufacture bone screw 102, core 112 is formed from a radiopaque or radiolucent biocompatible material, such as titanium, stainless steel, tungsten, alloy, or other material. Core 112 can be formed by any conventional method known in the art.
Shaft 108 is then formed about shaft portion 206 of core 112 to produce a blank 292, as shown in
In an alternative embodiment, blank 292 is formed using a roll wrap or table wrap process, as depicted in
It is also appreciated that non-winding methods can also be used for forming blank 292 about core 112. For example, compression molding or other conventional molding processes can be used to mold a fiber/adhesive mixture about core 112. In this embodiment, the fibers can be short fiber pieces that are distributed throughout the adhesive. Other known methods can alternatively be used to form blank 292.
As the impregnated fibers 294 or sheets 296 are only wound around shaft portion 206 of core 112, the head portion 204 of core 112 remains open and uncovered, as shown in
Once the blank 292 has been formed and allowed to cure, a grinder can be used, if desired, to smooth out any sharp edges remaining on the exterior surface 298 of the blank 292. Attachment member 126 and helical threads 120 (see
Tapered tip 124 (see
Turning to
If ring layer 148 is used, it is positioned or painted on or within threads 120 after threads 120 have been formed on exterior surface 122 of shaft 108, as depicted in
In an alternative method of manufacturing bone screw 102, after core 112 has been formed, blank 292 is configured so that both head portion 204 and shaft portion 206 can be formed therefrom. Specifically, depicted in
In one similar method of manufacture, body 290 can initially be formed by winding a radiolucent fiber/adhesive matrix about a core 112 that is formed from a high strength radiopaque material, such as a metal. In contrast to prior embodiments, however, core 112 is then slid out of body 290. The remaining passageway can then be backfilled by injecting a radiolucent material such as an epoxy or other adhesive within the passageway. Alternatively, a radiolucent core can be slid into the passageway and secured in place by an adhesive or other method of securing. As a result, the entire body and core are radiolucent. To help facilitate placement, positioning ring 147 (
Once bone screw 102 has been manufactured and assembled as described above, the polyaxial screw 100 can be assembled with bone screw 102 as one of its components. For example, turning to
Once bone screw 102 is seated within collar 104, pin 254 is advanced into pin hole 252. First end 256 of pin 254 is secured within pin hole 252 such as by welding, adhesive, press fit, or other mechanical engagements, such as threaded engagement. In this positions second end 258 of pin 254 projects into engagement slot 164 of bone screw 102. It is noted that pin 254 is spaced apart above floor 170 of engagement slot 164. As a result, bone screw 102 and collar 104 can continue to freely pivot relative to each other. However, because pin 254 extends over floor 170, head 110 is prevented from passing back up through collar 104. Pin 254 also functions to couple bone screw 102 and collar 104 together so that rotation of collar 104 or bone screw 102 also facilitates rotation of the other of the collar 104 or bone screw 102. As such, bone screw 102 can be implanted or removed simply by rotating collar 104. In alternative embodiments, it is appreciated that pin 62 can come in a variety of different configurations and can be mounted at a variety of different orientations and locations. Pin 62 can also be comprised of a radiolucent or radiopaque material.
In an alternative embodiment, head 110 is mounted on the collar 104 using pin 254, as described above, before head 110 is attached and secured to core 112 and shaft 108.
Depicted in
As depicted in
As depicted in
Floor 308 also has an interior surface 316 that bounds a second passageway 312 that extends through floor 308 so as to communicate with attachment recess 310. Interior surface 316 also has a substantially circularly transverse cross section with a flat 318 formed thereon.
Second passageway 312 is positioned so that when attachment member 126 is secured within attachment recess 310, first passageway 140 of shaft 108 is aligned with second passageway 312. It is also appreciated that second passageway 312 is also configured to receive and secure to head portion 204 of core 112 in the same way that head portion 204 is received and secured within second passageway 182 of head 110 (
A pair of spaced apart arms 320 and 321 project from opposing sides of base 304 in substantially parallel alignment. Each arm 320 and 321 has an interior surface 322. The opposing interior surfaces bound a substantially U-shaped channel 323 in which stabilizing rod 107 (
To aid in the implantation of bone screw 300, positioning ring 147 (
Depicted in
A number of different methods and embodiments are disclosed herein. It is appreciated that the different methods and components from the different embodiments can be mixed and matched to produce a variety of still other different embodiments.
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
Number | Name | Date | Kind |
---|---|---|---|
1828287 | MacBean | Oct 1931 | A |
2405909 | Smith et al. | Aug 1946 | A |
3455360 | Simons | Jul 1969 | A |
4063838 | Michael | Dec 1977 | A |
4265981 | Campbell | May 1981 | A |
4307979 | Killmeyer | Dec 1981 | A |
4329743 | Alexander et al. | May 1982 | A |
4403606 | Woo et al. | Sep 1983 | A |
4512038 | Alexander et al. | Apr 1985 | A |
4623290 | Kikuzawa et al. | Nov 1986 | A |
4778637 | Adams et al. | Oct 1988 | A |
4863330 | Olez et al. | Sep 1989 | A |
4863470 | Carter | Sep 1989 | A |
5084051 | Tormala et al. | Jan 1992 | A |
5127783 | Moghe et al. | Jul 1992 | A |
5209888 | Shimada et al. | May 1993 | A |
5246655 | Mitchell et al. | Sep 1993 | A |
5366773 | Schroll et al. | Nov 1994 | A |
5466237 | Byrd, III et al. | Nov 1995 | A |
5474555 | Puno et al. | Dec 1995 | A |
5540870 | Quigley | Jul 1996 | A |
5676146 | Scarborough | Oct 1997 | A |
5807051 | Heminger | Sep 1998 | A |
5951556 | Faccioli et al. | Sep 1999 | A |
6059769 | Lunn et al. | May 2000 | A |
6063090 | Schlapfer | May 2000 | A |
6099528 | Saurat | Aug 2000 | A |
6113826 | Tajima et al. | Sep 2000 | A |
6117173 | Taddia et al. | Sep 2000 | A |
6174329 | Callol et al. | Jan 2001 | B1 |
6203568 | Lombardi et al. | Mar 2001 | B1 |
6214921 | Bluett et al. | Apr 2001 | B1 |
6248105 | Schlapfer et al. | Jun 2001 | B1 |
6280442 | Barker et al. | Aug 2001 | B1 |
6302630 | Grant | Oct 2001 | B1 |
6340367 | Stinson et al. | Jan 2002 | B1 |
6342055 | Eisemann et al. | Jan 2002 | B1 |
6371957 | Amrein et al. | Apr 2002 | B1 |
6423067 | Eisermann | Jul 2002 | B1 |
6471705 | Biedermann et al. | Oct 2002 | B1 |
6565567 | Haider | May 2003 | B1 |
6575975 | Brace et al. | Jun 2003 | B2 |
6599290 | Bailey et al. | Jul 2003 | B2 |
6641586 | Varieur | Nov 2003 | B2 |
6660004 | Barker et al. | Dec 2003 | B2 |
6679883 | Hawkes et al. | Jan 2004 | B2 |
6712852 | Chung et al. | Mar 2004 | B1 |
6740086 | Richelsoph | May 2004 | B2 |
6837905 | Lieberman | Jan 2005 | B1 |
6955513 | Niku | Oct 2005 | B2 |
6974480 | Messerli et al. | Dec 2005 | B2 |
7150594 | Keener | Dec 2006 | B2 |
7169150 | Shipp et al. | Jan 2007 | B2 |
7192447 | Rhoda | Mar 2007 | B2 |
7235079 | Jensen et al. | Jun 2007 | B2 |
7235290 | Vallittu et al. | Jun 2007 | B2 |
7273481 | Lombardo et al. | Sep 2007 | B2 |
7318825 | Butler et al. | Jan 2008 | B2 |
7524190 | Levin | Apr 2009 | B2 |
7766942 | Patterson et al. | Aug 2010 | B2 |
7966711 | Keener | Jun 2011 | B2 |
7988710 | Jahjng et al. | Aug 2011 | B2 |
7998180 | Erickson et al. | Aug 2011 | B2 |
8267978 | Lindemann et al. | Sep 2012 | B2 |
8475505 | Nebosky et al. | Jul 2013 | B2 |
20020123751 | Fallin | Sep 2002 | A1 |
20020133158 | Saint Martin | Sep 2002 | A1 |
20030078583 | Biedemann et al. | Apr 2003 | A1 |
20040034430 | Faiahee | Feb 2004 | A1 |
20040127904 | Konieczynski et al. | Jul 2004 | A1 |
20040143265 | Landry et al. | Jul 2004 | A1 |
20040199251 | McCombe et al. | Oct 2004 | A1 |
20040210226 | Trieu | Oct 2004 | A1 |
20040210316 | King et al. | Oct 2004 | A1 |
20040215195 | Shipp et al. | Oct 2004 | A1 |
20040243129 | Moumene et al. | Dec 2004 | A1 |
20050187550 | Grusin | Aug 2005 | A1 |
20050187555 | Biedermann et al. | Aug 2005 | A1 |
20050203516 | Biedermann et al. | Sep 2005 | A1 |
20050203517 | Jahng et al. | Sep 2005 | A1 |
20050203519 | Harms et al. | Sep 2005 | A1 |
20050216081 | Taylor | Sep 2005 | A1 |
20050228388 | Brodke et al. | Oct 2005 | A1 |
20050228479 | Pavcnik et al. | Oct 2005 | A1 |
20060041259 | Paul et al. | Feb 2006 | A1 |
20060084986 | Grinberg et al. | Apr 2006 | A1 |
20060085072 | Funk et al. | Apr 2006 | A1 |
20060089644 | Felix | Apr 2006 | A1 |
20060142758 | Petit | Jun 2006 | A1 |
20060149228 | Schlapfer et al. | Jul 2006 | A1 |
20060195093 | Jahng | Aug 2006 | A1 |
20060200140 | Lange | Sep 2006 | A1 |
20060235410 | Ralph et al. | Oct 2006 | A1 |
20060247638 | Trieu et al. | Nov 2006 | A1 |
20060276788 | Berry et al. | Dec 2006 | A1 |
20070123879 | Songer et al. | May 2007 | A1 |
20070156145 | Demakas et al. | Jul 2007 | A1 |
20070190230 | Trieu et al. | Aug 2007 | A1 |
20070233071 | Dewey et al. | Oct 2007 | A1 |
20070233073 | Wisnewski et al. | Oct 2007 | A1 |
20070250167 | Bray et al. | Oct 2007 | A1 |
20070270851 | Erickson et al. | Nov 2007 | A1 |
20080033437 | Shipp et al. | Feb 2008 | A1 |
20080065070 | Freid et al. | Mar 2008 | A1 |
20080077133 | Schulze et al. | Mar 2008 | A1 |
20080082103 | Hutton et al. | Apr 2008 | A1 |
20080083613 | Oi et al. | Apr 2008 | A1 |
20080086127 | Patterson et al. | Apr 2008 | A1 |
20080086129 | Lindemann et al. | Apr 2008 | A1 |
20080091214 | Richelsoph | Apr 2008 | A1 |
20080097432 | Schulze | Apr 2008 | A1 |
20080125777 | Veldman et al. | May 2008 | A1 |
20080154306 | Heinz | Jun 2008 | A1 |
20080154367 | Justis et al. | Jun 2008 | A1 |
20080243185 | Felix et al. | Oct 2008 | A1 |
20090082810 | Bhatnagar et al. | Mar 2009 | A1 |
20090093819 | Joshi | Apr 2009 | A1 |
20090093844 | Jackson | Apr 2009 | A1 |
20090112265 | Hudgins et al. | Apr 2009 | A1 |
20090240284 | Randol et al. | Sep 2009 | A1 |
20090275983 | Veldman et al. | Nov 2009 | A1 |
20090326582 | Songer et al. | Dec 2009 | A1 |
20100042215 | Stalcup et al. | Feb 2010 | A1 |
20100063550 | Felix | Mar 2010 | A1 |
20100114167 | Wilcox et al. | May 2010 | A1 |
20100160967 | Capozzoli | Jun 2010 | A1 |
20120109207 | Trieu | May 2012 | A1 |
Number | Date | Country |
---|---|---|
44 43 051 | Oct 1996 | DE |
100 65 799 | Apr 2002 | DE |
2 899 787 | Oct 2007 | FR |
2 294 399 | Jan 1996 | GB |
2005-270250 | Oct 2005 | JP |
2006-187658 | Jul 2006 | JP |
2007-307368 | Nov 2007 | JP |
WO 9404095 | Mar 1994 | WO |
WO 2007127845 | Nov 2007 | WO |
Entry |
---|
International Search and Written Opinion issued Feb. 19, 2010, PCT/US2009/056508, filed Sep. 10, 2009. |
Office Action dated Nov. 9, 2011, issued in U.S. Appl. No. 12/557,081, filed Sep. 10, 2009. |
Office Action dated Jan. 19, 2012, issued in U.S. Appl. No. 12/719,765, filed Mar. 8, 2010. |
PCT/US2011/024935, May 23, 2011, International Search Report and Written Opinion. |
PCT/US2010/048243, Nov. 10, 2010, International Search Report and Written Opinion. |
VLS System Variable Locking Screw, Interpore Cross International, 2001. |
EBI Spine Systems, EBI Ωmega21 Spinal Fixation System, Surgical Technique, published at least as early as Sep. 1, 2006. |
Click'X Top Loading System, Technique Guide, Synthes Spine 2003. |
Synergy IQ, Low Back Surgical Technique, Interpore Cross International, 2003. |
S. Kawahara et al., Summary of Clinical Imaging Diagnosis of Implant Materials for Breast Augmentation, Ann Plast Surg., Jul. 2006; 57(1), pp. 6-12 (1 page). |
Office Action dated May 3, 2013, issued in U.S. Appl. No. 13/063,605, filed Mar. 11, 2011. |
Final Office Action dated Jun. 6, 2012, issued in U.S. Appl. No. 12/577,081, filed Sep. 10, 2009. |
Final Office Action dated May 9, 2012, issued in U.S. Appl. No. 12/719,765, filed Mar. 8, 2010. |
Office Action dated Aug. 17, 2012, issued in U.S. Appl. No. 12/719,765, filed Mar. 8, 2010. |
Office Action issued dated Feb. 16, 2013, issued in Chinese Application No. 200980144925.0, filed Sep. 11, 2011. |
Office Action dated Sep. 14, 2011 issued in EP Application No. 09792417.9, filed Sep. 11, 2011. |
Final Office Action dated Apr. 13, 2013 issued in U.S. Appl. No. 12/719,765, filed Mar. 8, 2010. |
Office Action dated Apr. 11, 2013, issued in U.S. Appl. No. 12/719,765, filed Mar. 8, 2010. |
Office Action dated May 3, 2013, issued in U.S. Appl. No. 13/063,605, Mar. 11, 2011. |
Office action dated Jul. 30, 2013, issued in MX/a/2011/002706, filed Mar. 11, 2011. |
Office Action dated Oct. 15, 2013, issued in JP 2011-526971, filed May 16, 2011. |
Office Action dated Feb. 16, 2013, issued in CN200980144925.0. |
Office Action dated Nov. 18, 2013, issued in U.S. Appl. No. 12/719,765, filed Mar. 8, 2010. |
Office Action dated Jan. 16, 2014, issued in U.S. Appl. No. 13/063,605, filed Mar. 11, 2011. |
Office Action dated Nov. 6, 2013, issued in CN200980144925.0. |
Office Action dated Aug. 15, 2013, issued in U.S. Appl. No. 12/557,081, filed Sep. 10, 2009. |
Office Action dated Jan. 2, 2014, issued in U.S. Appl. No. 12/557,081, filed Sep. 10, 2009. |
Office Action dated Feb. 20, 2014, issued in U.S. Appl. No. 12/557,081, filed Sep. 10, 2009. |
Office Action dated Apr. 23, 2014, issued in U.S. Appl. No. 13/063,605, filed Mar. 11, 2011. |
Number | Date | Country | |
---|---|---|---|
20100063550 A1 | Mar 2010 | US |