Patent Grant
7955360
The present invention relates to a device for implantation into a disc space between adjacent vertebral bodies in the human spine, and a device and method for working on those portions of the vertebral bodies adjacent that disc space to remove bone material and thereby access vascular bone, and preferably a device and method for protecting the neurological structures such as nerve roots and dural sac proximate the implantation site while providing protected access to form an implantation space and then access the implantation space formed between the adjacent vertebral bodies for insertion of an implant therein. The device and associated method are used to position (space apart and align) the vertebral bodies, guide the formation of a surface into or through each of the vertebral body surfaces that are adjacent the intervertebral disc space, and may further be utilized to guide an interbody spinal implant into the implantation space.
In one embodiment, the device and associated method are used to make an implantation space to insert an implant of a height having a known correspondence to the height of the space created. In another embodiment, the device and associated method are used to make an implantation space of known and specific dimensions (e.g., width; depth; and height) and with certain preferred embodiments, permit passage through the device of an implant having a height greater than the height of the implantation space formed through the device.
Human vertebral bodies are comprised of a dense, hard outer shell and a relatively less dense inner mass. The hard outer shell is very densely compacted cancellous bone, resembling cortical bone at all but high magnification, and is generally referred to as the cortex. The inner mass is a softer cancellous bone. As shown in
The spinal disc that resides between adjacent vertebral bodies maintains the spacing between those vertebral bodies and, in a healthy spine, allows for relative motion between the vertebrae. At the time of surgery, for example in the instance of interbody fusion, that is, where fusion is intended to occur between adjacent vertebral bodies of a patient's spine, the surgeon typically prepares an opening at the site of the intended fusion by removing a substantial amount of the nucleus disc material that exists between the adjacent vertebral bodies to be fused. Because the outermost layers of bone of the vertebral end plate are relatively inert to new bone growth, the surgeon will typically work on the end plate to remove at least the outermost cell layers of bone to gain access to the blood-rich, vascular bone tissue within the vertebral body. In this manner, the vertebrae are prepared in a way that encourages new bone growth consistent with fusion.
Devices for assisting a surgeon in accessing the disc space and adjacent vertebral bodies are known. Drill guides and boxed chisels have been used to form an implantation space between the adjacent vertebral bodies for insertion of a spinal implant therein. Applicant invented a guard and instrument system particularly well suited for use in the lumbar spine and of unequalled advantage for use posteriorly therein through which both the implantation space can be formed and a spinal implant can be inserted into the implantation space, as disclosed in U.S. Pat. No. 5,015,247, filed Jun. 13, 1988, which is hereby incorporated by reference.
Applicant also invented a guard having disc penetrating extension(s), which extensions have utility for stabilizing the guard, stabilizing the adjacent vertebrae relative to each other, urging the vertebrae apart if desired, and aligning the vertebrae to each other if desired to form the implantation space through the guard and insert the spinal implant through the guard into the implantation space, as disclosed in U.S. Pat. No. 6,080,155 filed Feb. 27, 1995, incorporated herein by reference. The disc penetrating extensions can have either parallel or angled upper and lower surfaces in contact with the adjacent vertebral bodies to place the adjacent vertebral bodies parallel to one another or at an angle to one another. The disclosed disc penetrating extensions are rigid.
To obtain a particular orientation between the adjacent vertebral bodies a surgeon selects a guard having a predetermined orientation between the upper and lower surfaces of the disc penetrating extensions. In the case of disc penetrating extensions that have upper and lower surfaces diverging from one another as would be useful for posterior lumbar interbody fusion (PLIF), so as to be higher at the insertion or distal end than at the trailing or proximal end of the extensions, a tapered leading end is used to facilitate insertion of the disc penetrating extensions into the disc space. Such a configuration allows for lordosis of the lumbar segment of a spine to be operated upon from a posterior approach. For extensions that have diverging upper and lower surfaces, additional force is required to drive the guard and extensions into place. Then, after an implant is inserted, it may be difficult to remove a distractor element such as a guard having disc penetrating extensions having a maximum height greater then the height of the disc space posterior height.
Present methods of forming the implantation space between adjacent vertebral bodies generally include the use of one or more of the following: hand held biting and grasping instruments known as rongeurs; drills and drill guides; rotating burrs driven by a motor; and osteotomes and chisels. Applicant has taught various novel instruments to mill out the recipient fusion site across the height of the disc space including various cutting/milling frames and various novel cutters as disclosed in applicant's U.S. Pat. No. 6,159,214, incorporated herein by reference. The surgeon must work upon the adjacent end plates of the adjacent vertebrae to access the vascular, cancellous bone that is best suited for participating in the fusion and causing active bone growth, and also to attempt to obtain an appropriately shaped surface in the vertebral bodies to receive the implant. Because the end plates of the adjacent vertebrae are not flat, but rather have a complex biological as opposed to geometrical curved shape, it is necessary to conform the vertebrae to the shape of the implant to be received therebetween.
Suitable devices for forming a disc space disclosed by applicant in U.S. Pat. No. 6,083,228, and U.S. patent application Ser. No. 09/663,311, filed Sep. 15, 2000, both of which are hereby incorporated by reference. Both of these disclosures describe various abrading elements and cutting wheels used to form the implantation space. U.S. patent application Ser. No. 09/663,311 discloses the use of a guard or frame having disc penetrating extensions that could be either parallel or angled to properly orient the vertebral bodies relative to one another prior to forming the implantation space.
There is a need for a guard for use in posterior lumbar surgery to create an interbody implantation space while providing for spinal lordosis and while being easily and safely inserted and as easily and safely removed.
In accordance with the purposes of the present invention, as embodied and broadly described herein, a guard of this invention is provided for use in spinal surgery across a disc space between two adjacent vertebral bodies of a human spine. The guard includes a body having a leading end and an opposite trailing end. The body has a first portion and a second portion proximate the leading end that are in pivotal relationship to one another between an open position and a closed position. The first and second portions each have opposed interior portions that define an opening for providing protected access to the disc space and the adjacent vertebral bodies. The opposed interior portions are adapted to guide a bone removal device therethrough that is sized to form an implantation space across the disc space and at least in part into the adjacent vertebral bodies. The guard also includes at least one disc space penetrating extension extending from the leading end of the body that is adapted for insertion at least in part into the disc space. The extension has a first portion extending from the first portion of the body that has a contact surface adapted to bear against one of the adjacent endplates of the adjacent vertebral bodies. The extension also has a second portion extending from the second portion of the body that has a contact surface adapted to bear against the other of the adjacent endplates of the adjacent vertebral bodies. The contact surfaces of the first and second portions of the extension are in pivotal relationship to one another from an insertion position to a deployed position to move the adjacent vertebral bodies apart upon movement of the first and second portions of the body from the open position to the closed position.
The body of the guard may have a generally rectangular, square, circular, oval, or elliptical cross section along at least a portion of the length of the body. The leading end of the body may be adapted to conform at least in part to the exterior surfaces of the adjacent vertebral bodies by having the leading end cut back to permit the contact surfaces to have an intimate fit with the vertebral bodies when the guard is in the deployed position. The body may include at least one window adapted to permit the surgeon to observe the surgery though the window and/or permit portions of bone extending though the window to be removed by the bone removal device passing through the body of the guard.
The guard may include a second disc penetrating extension diametrically opposite to a first disc penetrating extension. Each disc penetrating extension may have a tapered leading end and have contact surfaces that are parallel to each other over a substantial portion of the length of each extension when in the insertion position. The first and second portions of each disc penetrating extension may be adapted to touch one another when in the insertion position.
The first and second portions of the body may be hinged to one another to rotatably articulate relative to one another about an axis of rotation that is fixed relative to the mid-longitudinal axis of the guard when moved from the open position to the closed position. The body may have an interior surface having a cooperating surface for guiding a corresponding cooperating surface on the bone removal device.
The guard may include an impaction cap adapted to cooperatively engage the trailing end of the body when the body is in the open position. The guard may include a lock in the form of a collar adapted to cooperatively engage the body of the guard when the body is in the closed position to hold the body in the closed position.
The guard may form part of a combined spinal surgery set that includes a bone removal device, an implant driver, and a spinal implant, or any combination thereof. The bone removal device may have a working end having at least two cutters selected to create a predetermined surface contour into each of the adjacent vertebral bodies as the working end is moved. The implant may be sized and shaped to at least in part match the space formed in the spine by the bone removal device and may be adapted to be combined or treated with a natural or artificial bone growth promoting material or substance.
In accordance with the purposes of another embodiment of the present invention, as embodied and broadly described herein, a guard of this invention is provided for use in spinal surgery across a disc space between two adjacent vertebral bodies of the human spine. The guard includes a body having an opening for providing protected access to the disc space and the adjacent vertebral bodies. The opening has opposed interior portions that are adapted to guide therethrough a bone removal device sized to form an implantation space across the disc space and at least in part into the adjacent vertebral bodies. The guard also includes at least one disc space penetrating extension extending from the body that is adapted for insertion at least in part into the disc space. The disc penetrating extension has a first portion having a contact surface adapted to bear against one of the adjacent endplates of the adjacent vertebral bodies and a second portion having a contact surface adapted to bear against the other of the adjacent endplates of the adjacent vertebral bodies. The contact surfaces of the first and second portions are adapted to rotatably articulate relative to one another between an insertion position and a deployed position to move the adjacent vertebral bodies apart.
In accordance with the purposes of a further embodiment of the present invention, as embodied and broadly described herein, a method of this invention is provided for inserting a spinal implant at least in part within and across the generally restored height of a disc space between two adjacent vertebral bodies of a human spine. The method includes the steps of positioning into the disc space between the adjacent vertebral bodies a guard having a body and an extension for insertion at least in part into the disc space and for bearing against end plates of the adjacent vertebral bodies to restore the spacing of the disc space between the adjacent vertebrae, the guard having a first portion oriented toward one of the adjacent vertebral bodies and a second portion oriented toward another of the adjacent vertebral bodies, the first and second portions being rotatably articulating relative to one another such that when the body moves from an open position to a closed position the extension moves from an insertion position to a deployed position to move the adjacent vertebral bodies apart; rotatably articulating the guard to move the body from the open position to the closed position and the extension from the insertion position to the deployed position to move the adjacent vertebral bodies apart; and forming, through the guard, an opening across height of the disc space and into at least a portion of the endplates of the adjacent vertebral bodies.
The method may include the further steps of performing the spinal implant surgery from a position posterior to the transverse processes of the vertebrae adjacent the disc space; performing the procedure on both sides of the spinal midline of the spine; securing the body of the guard in the closed position; and inserting two implants into the spine.
The positioning step may include the further steps of positioning a guard having multiple extensions for insertion into the disc space; placing the body of the guard in the open position; driving the extension into the disc space; and inducing angulation to the adjacent vertebral bodies relative to one another.
The rotatably articulating step may include the further steps of orienting the adjacent vertebral bodies in a predetermined relationship relative to each other; and inducing lordosis to the adjacent vertebral bodies.
The forming step may include the further steps of inserting the bone removal device through the guard to a desired depth; forming the implantation space with the bone removal device; and forming opposed receiving surfaces in the end plates of the vertebral bodies corresponding at least in part in size, shape, and contour to an implant to be implanted. The forming step may include any one of milling, drilling, reaming, abrading, chiseling, and trephining the implantation space.
The method may include the further steps of inserting the implant into the implantation space through the guard, or inserting the implant into the implantation space after removing the guard from the disc space. The inserting step may include the further steps of inserting the implant using an implant inserter; and removing the implant inserter after using the implant inserter to insert the implant into the implantation space. The inserting step may also include inserting a spinal implant that is a spinal fusion implant that has upper and lower surfaces for placement between and in contact with the adjacent vertebral bodies, each of the upper and lower surfaces having at least one opening adapted to permit for the growth of bone from adjacent vertebral body to adjacent vertebral body through the implant. The inserting step may include inserting a spinal implant having a hollow between the upper and lower surfaces; inserting a spinal implant that is expandable; and inserting a spinal implant having surface projections configured to resist expulsion of the implant from the implantation space. The inserting step may include inserting any one of an inert spacer, an artificial disc, or a bone graft.
The inserting step may further include the steps of compressively loading the implant with fusion promoting substances selected from one of bone, bone derived products, demineralized bone matrix, ossifying proteins, bone morphogenetic protein, hydroxyapatite, and genes coding for the production of bone; and retaining the fusion promoting substance within the implant after the loading step. The step of retaining the fusion promoting substance may include attaching a cap to the implant.
The inserting step may also include the steps of treating the implant with a fusion promoting substance; inserting an implant in combination with a chemical substance adapted to inhibit scar formation; inserting an implant in combination with an antimicrobial material; inserting an implant including a fusion promoting substance or having a bone ingrowth surface; inserting an implant being at least in part of one of bone and bone growth promoting material; and inserting an implant in combination with at least one of a fusion promoting substance, bone, bone growth promoting material, bone derived products, demineralized bone matrix, ossifying proteins, bone morphogenetic protein, hydroxyapatite, and genes coding for the production of bone.
The method may further include the steps of collapsing the extensions and removing the guard form the disc space.
The accompanying drawings, which are incorporated in and constitute a part of this specification, are by way of example only and not limitation, and illustrate several embodiments of the invention, which together with the description, serve to explain the principles of the invention. The scope of the invention is limited only by the scope of the claims as from the present teachings other embodiments of the present invention shall be apparent to those skilled in the art.
The present invention has a number of embodiments, at least some of which have as an object of at least one embodiment of the present invention to provide a device and method for quickly, safely, effectively, and accurately spacing apart and positioning a pair of adjacent vertebral bodies to receive an implant, which is anything designed to be left in the body for an extended length of time, working upon the properly positioned vertebral body end plate regions adjacent a disc space so as to remove bone to produce a receiving surface corresponding to an implant having upper and lower surfaces to be implanted between the adjacent vertebrae.
It is a further object of at least one embodiment of the present invention to provide a device and method that permits the insertion of disc penetrating extensions of a guard into the disc space posteriorly in a first position that facilitates insertion and removal of the disc penetrating extensions into and from the disc space and then permits the disc penetrating extensions to be moved into a second position that orients the adjacent vertebral bodies in a preferred lordotic relationship relative to the device and each other.
It is a further object of the present invention, in at least certain embodiments, to provide a device capable of working upon both of the vertebral body end plate regions adjacent a disc space to produce opposed receiving surfaces in the adjacent end plates corresponding at least in part in size, shape, and contour to an implant to be implanted with the exception of the height of the implant, which may be greater than the distance between the opposed receiving surfaces that may be distracted or otherwise moved apart by insertion of the implant, and in so doing to define the shape to the implantation space.
It is a further object of the present invention to provide a device that works with linear insertion, i.e., insertion along a single axis, and without removing the device during the process of disc space preparation and, if so desired with certain embodiments of the present invention, implant placement.
These and other objectives of the present invention will occur to those of ordinary skill in the art based on the description of the preferred embodiments of the present invention described below. However, not all embodiments of the inventive features of the present invention need achieve all the objectives identified above, and the invention in its broadest aspects is not limited to the preferred embodiments described herein.
The accompanying drawings together with the description, serve to explain the objects, advantages, and principles of the invention. In the drawings:
Reference is now made in detail to the present preferred embodiments of the invention, as illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used throughout the drawings to refer to the same or like parts. For example, reference numbers without a prime are used in relation to a guard having a rectangular cross-section such as described with reference to
In preferred embodiments, but not requisite, various windows 108 in guard body 102 allow the surgeon to remove portions of a facet, pedicle, or spinous process in the same procedure as the bone removal of the vertebral bodies for creating an insertion space therebetween. It is within the scope of the present invention to use a variety of window shapes in addition to the shape depicted to accommodate projecting bone structures. Window 108 also may be used in observing the procedure at various stages of the operation and if so desired for passing instruments therethrough. Rather than or in addition to a window 108, the guard may have one or more indentations of the wall of the body 102 to make room for a facet, pedicle, or spinous process. As best seen in top view
A perspective view of an impaction cap 124 for use with guard 100 is shown in
A variety of bone removal devices are useable with the guard of the present invention. For example,
In
In
In
In another embodiment shown in
Guard 100 may also include one or more tracks 148 to direct cutting device 128 while accessing the disc space and adjacent vertebral bodies via the elongated opening in guard 100. Such tracks 148 may include any surface designed to direct cutting device 128. Tracks 148 also serve to keep cutter device 128 from easily rotating or moving side to side within the guard opening.
As best shown in
Implant 150 may be made of artificial or naturally occurring materials suitable for implantation in the human spine. Implant 150 may also take a variety of shapes, for example, rectangular or square cross section. Implant 150 can comprise bone including, but not limited to, cortical bone. Implant 150 can also be formed of material other than bone, such as metal including, but not limited to, titanium and its alloys or ASTM material, surgical grade plastics, plastic composites, ceramics, or other materials suitable for use as an interbody implant. The plastics may be bioresorbable. Implant 150 can further be formed of bone growth promoting materials, including but not limited to, bone morphogenetic proteins, hydroxyapatite, and genes coding for the production of bone. Implant 150 can be treated with a bone growth promoting substance, can be a source of osteogenesis, or can be at least in part bioabsorbable. Implant 150 also can be formed of a porous material. Further, implant 150 may be used in combination with chemical substances and/or compounds applied at the trailing end of the implant to inhibit scar formation, and a cap may be of benefit in shielding fusion-promoting substances contained in the implant from these scar formation inhibiting chemicals and compounds.
As illustrated in
In summary, a preferred method of the present invention includes: performing from a posterior approach in the lumber spine at least a partial laminectomy sufficient for access to the disc space; performing at least a partial discectomy, which more preferably provides sufficient space to receive the guard disc penetrating extensions to a depth which may be generally similar to the depth of implant 150 to be received; retracting and protecting the dural sac; inserting guard 100 with extensions 110,112 into the disc space; inducing lordosis to the adjacent vertebral bodies; securing body 102 of guard 100 in the closed position; and inserting cutting device 128 through guard 100 to a desired depth. The depth of insertion may be monitored by x-ray. At this point debris may be removed by irrigation suction from within and/or about guard 100. Extensions 110, 112 are then collapsed and guard 100 is then removed. Any additional debris may be removed after removal of guard 100, again by irrigation suction. Implant 150 may be inserted through guard 100 prior to its removal from the disc space, or may be inserted after guard 100 is removed while retractors are utilized as needed to protect the proximate neural structures.
Guard 100 preferably is used for posterior lumbar interbody implantation procedures. Guard 100 includes a height, a width, and a distance between its front and rear portion. The height of body 102 is preferably between 8-25 mm and the opening height is preferably 8-20 mm. The width of the opening of body 102 is preferably 10-25 mm. Disc penetrating extensions 110, 112 may have any shape or configuration suitable for the intended purpose disclosed herein including extensions with parallel or angled upper and lower surfaces. Preferably, disc penetrating extensions 110, 112 have a combined height when closed of 6-18 mm and a length of 12-32 mm. For posterior lumbar interbody fusion, cutting device 128 is preferably 8-20 mm in height and 10-25 mm in width. These dimensions could be greater or less and still be useful for their stated purpose while still being within the inventive scope of the present invention.
As shown in
In
As shown in
Guard 100′ preferably is used for posterior lumbar interbody implantation procedures. Guard 100′ includes a height, a width, and a distance between its front and rear portion. The height of body 102′ is preferably between 8-25 mm and the opening height is preferably 8-20 mm. Disc penetrating extensions 110′, 112′ may have any shape or configuration suitable for the intended purpose disclosed herein including extensions with parallel or angled upper and lower surfaces in the closed or open position. Preferably, disc penetrating extensions 110′, 112′ have a combined height when closed of 6-18 mm and a length of 12-32 mm. For posterior lumbar interbody fusion, drill 128′ is preferably 8-20 mm in height. These dimensions could be greater or less and still be useful for their intended purpose while still being within the inventive scope of the present invention.
Although various embodiments of the present invention have been disclosed for purposes of illustration and are for purposes of example only and not limitation, it will be understood by those of ordinary skill in the art that changes, modifications, and substitutions may be incorporated in these embodiments without departing from the spirit of the present invention or the scope of the appended claims.
This application is a continuation of U.S. application Ser. No. 10/125,847, filed Apr. 19, 2002 (now U.S. Pat. No. 7,211,085); which is a national stage application claiming priority to PCT Application No. PCT/US02/06021, filed Mar. 1, 2002; which claims the benefit of U.S. Provisional Application No. 60/272,381, filed Mar. 1, 2001, and U.S. Provisional Application No. 60/272,382, filed Mar. 1, 2001; the disclosures of which are all incorporated herein by reference.
| Number | Name | Date | Kind |
|---|---|---|---|
| 605652 | Pitt | Jun 1868 | A |
| 514799 | Wildt | Feb 1894 | A |
| 563236 | Penhall | Jun 1896 | A |
| 611038 | Lohman | Sep 1898 | A |
| 617247 | Gholson | Jan 1899 | A |
| 751475 | De Vilbiss | Feb 1904 | A |
| 1222478 | Sheaff | Apr 1917 | A |
| 1607194 | Gammon et al. | Nov 1926 | A |
| 1635137 | Mullens | Jul 1927 | A |
| 1796072 | Baer | Mar 1931 | A |
| 2300040 | Betts | Oct 1942 | A |
| 2320709 | Arnesen | Jun 1943 | A |
| 2807259 | Guerriero | Sep 1957 | A |
| 3054398 | Kobler | Sep 1962 | A |
| 3486505 | Morrison | Dec 1969 | A |
| 3747592 | Santos | Jul 1973 | A |
| 3752149 | Ungar | Aug 1973 | A |
| 3789829 | Hasson | Feb 1974 | A |
| 3807393 | McDonald | Apr 1974 | A |
| 3890961 | Moore et al. | Jun 1975 | A |
| 3985125 | Rose | Oct 1976 | A |
| 4130938 | Uhlmann | Dec 1978 | A |
| 4263899 | Burgin | Apr 1981 | A |
| 4385626 | Danz | May 1983 | A |
| 4545374 | Jacobson | Oct 1985 | A |
| 4638792 | Burgin | Jan 1987 | A |
| 4690132 | Bayer et al. | Sep 1987 | A |
| 4716901 | Jackson et al. | Jan 1988 | A |
| 4765311 | Kulik et al. | Aug 1988 | A |
| 4807600 | Hayes | Feb 1989 | A |
| 4817587 | Janese | Apr 1989 | A |
| 4862891 | Smith | Sep 1989 | A |
| 4989587 | Farley | Feb 1991 | A |
| 5015247 | Michelson | May 1991 | A |
| 5015255 | Kuslich | May 1991 | A |
| 5020519 | Hayes et al. | Jun 1991 | A |
| 5088472 | Fakhrai | Feb 1992 | A |
| 5125396 | Ray | Jun 1992 | A |
| 5304119 | Balaban et al. | Apr 1994 | A |
| 5342384 | Sugarbaker | Aug 1994 | A |
| 5377667 | Patton et al. | Jan 1995 | A |
| 5431658 | Moskovich | Jul 1995 | A |
| 5484437 | Michelson | Jan 1996 | A |
| 5503617 | Jako | Apr 1996 | A |
| 5509893 | Pracas | Apr 1996 | A |
| 5512038 | O'Neal et al. | Apr 1996 | A |
| 5571109 | Bertagnoli | Nov 1996 | A |
| 5593409 | Michelson | Jan 1997 | A |
| 5609635 | Michelson | Mar 1997 | A |
| 5630843 | Rosenberg | May 1997 | A |
| 5681265 | Maeda et al. | Oct 1997 | A |
| 5776199 | Michelson | Jul 1998 | A |
| 5785647 | Tompkins et al. | Jul 1998 | A |
| 5785648 | Min | Jul 1998 | A |
| 5788630 | Furnish | Aug 1998 | A |
| 5795291 | Koros et al. | Aug 1998 | A |
| 5797909 | Michelson | Aug 1998 | A |
| 5803904 | Mehdizadeh | Sep 1998 | A |
| 5846249 | Thompson | Dec 1998 | A |
| 5860973 | Michelson | Jan 1999 | A |
| 5866113 | Hendriks et al. | Feb 1999 | A |
| 5868668 | Weiss | Feb 1999 | A |
| 5876457 | Picha et al. | Mar 1999 | A |
| 5885210 | Cox | Mar 1999 | A |
| 5895426 | Scarborough et al. | Apr 1999 | A |
| 5899854 | Slishman | May 1999 | A |
| 5910174 | Finn | Jun 1999 | A |
| 5928139 | Koros et al. | Jul 1999 | A |
| 5931777 | Sava | Aug 1999 | A |
| 5944658 | Koros et al. | Aug 1999 | A |
| 5951564 | Schroder et al. | Sep 1999 | A |
| 5954635 | Foley et al. | Sep 1999 | A |
| 5968098 | Winslow | Oct 1999 | A |
| 5993385 | Johnston et al. | Nov 1999 | A |
| 5997474 | Batchelor | Dec 1999 | A |
| 6004341 | Zhu et al. | Dec 1999 | A |
| 6010509 | Delgado et al. | Jan 2000 | A |
| 6012363 | Minkin | Jan 2000 | A |
| 6024696 | Hoftman et al. | Feb 2000 | A |
| 6042540 | Johnston et al. | Mar 2000 | A |
| 6063088 | Winslow | May 2000 | A |
| 6080155 | Michelson | Jun 2000 | A |
| 6083228 | Michelson | Jul 2000 | A |
| 6096044 | Boyd et al. | Aug 2000 | A |
| 6096046 | Weiss | Aug 2000 | A |
| 6099547 | Gellman et al. | Aug 2000 | A |
| 6139493 | Koros et al. | Oct 2000 | A |
| 6139563 | Cosgrove et al. | Oct 2000 | A |
| 6149583 | Vierra et al. | Nov 2000 | A |
| 6159214 | Michelson | Dec 2000 | A |
| 6159215 | Urbahns et al. | Dec 2000 | A |
| 6190414 | Young et al. | Feb 2001 | B1 |
| 6210412 | Michelson | Apr 2001 | B1 |
| 6224545 | Cocchia et al. | May 2001 | B1 |
| 6224604 | Suddaby | May 2001 | B1 |
| 6224607 | Michelson | May 2001 | B1 |
| 6287322 | Zhu et al. | Sep 2001 | B1 |
| 6302842 | Auerbach et al. | Oct 2001 | B1 |
| 6309349 | Bertolero et al. | Oct 2001 | B1 |
| 6416467 | McMillin et al. | Jul 2002 | B1 |
| 6431658 | Nakajima et al. | Aug 2002 | B1 |
| 6450952 | Rioux et al. | Sep 2002 | B1 |
| 6485517 | Michelson | Nov 2002 | B1 |
| 6494883 | Ferree | Dec 2002 | B1 |
| 6517544 | Michelson | Feb 2003 | B1 |
| 6520967 | Cauthen | Feb 2003 | B1 |
| 6692501 | Michelson | Feb 2004 | B2 |
| 6699247 | Zucherman et al. | Mar 2004 | B2 |
| 6712795 | Cohen | Mar 2004 | B1 |
| 6712825 | Aebi et al. | Mar 2004 | B2 |
| 6749563 | Stihl | Jun 2004 | B2 |
| 6851430 | Tsou | Feb 2005 | B2 |
| 6896680 | Michelson | May 2005 | B2 |
| 6923810 | Michelson | Aug 2005 | B1 |
| 6986772 | Michelson | Jan 2006 | B2 |
| 7211085 | Michelson | May 2007 | B2 |
| 7261688 | Smith et al. | Aug 2007 | B2 |
| 7314468 | Michelson | Jan 2008 | B2 |
| 20020111680 | Michelson | Aug 2002 | A1 |
| 20020123753 | Michelson | Sep 2002 | A1 |
| 20020128659 | Michelson | Sep 2002 | A1 |
| 20030023209 | Gruskin et al. | Jan 2003 | A1 |
| 20030135220 | Cauthen | Jul 2003 | A1 |
| 20030229401 | Mansouri et al. | Dec 2003 | A1 |
| 20040073309 | Bianchi et al. | Apr 2004 | A1 |
| 20040082958 | Michelson | Apr 2004 | A1 |
| 20040181233 | Michelson | Sep 2004 | A1 |
| 20050043741 | Michelson | Feb 2005 | A1 |
| 20050216085 | Michelson | Sep 2005 | A1 |
| 20070016220 | Michelson | Jan 2007 | A1 |
| Number | Date | Country |
|---|---|---|
| 28 01 696 | Jul 1979 | DE |
| 20016971 | Jan 2001 | DE |
| 0455282 | Dec 1994 | EP |
| 0 796 593 | Sep 1997 | EP |
| 1 192 905 | Apr 2002 | EP |
| 613642 | Nov 1926 | FR |
| 2702364 | Mar 1993 | FR |
| 2019136 | Sep 1994 | RU |
| 2157656 | Oct 2000 | RU |
| 2192177 | Nov 2002 | RU |
| WO 9320741 | Oct 1993 | WO |
| WO 9963891 | Dec 1999 | WO |
| WO 0019911 | Apr 2000 | WO |
| WO 0156513 | Aug 2001 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20070213739 A1 | Sep 2007 | US |
| Number | Date | Country | |
|---|---|---|---|
| 60272381 | Mar 2001 | US | |
| 60272382 | Mar 2001 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10125847 | US | |
| Child | 11799406 | US |
