US20070255406A1 - Devices, apparatus, and methods for bilateral approach to disc augmentation - Google Patents

Abstract

A method of augmenting a nucleus pulposus of an intervertebral disc comprises forming a first opening in an annulus of the intervertebral disc and forming a second opening in the annulus of the intervertebral disc. The method further comprises providing a space creation instrument including an expandable spacing device and introducing the spacing device through the first opening and into the nucleus pulposus. The method further comprises introducing a material delivery instrument through the second opening and into the nucleus pulposus and expanding the spacing device to create a space within the nucleus pulposus. The method also comprises injecting a biocompatible material from the material delivery instrument and into the space within the nucleus pulposus.

Description

BACKGROUND
• Within the spine, the intervertebral disc functions to stabilize and distribute forces between vertebral bodies. The intervertebral disc comprises a nucleus pulposus which is surrounded and confined by the annulus fibrosis. Intervertebral discs are prone to injury and degeneration. For example, herniated discs typically occur when normal wear, or exceptional strain, causes a disc to rupture. Degenerative disc disease typically results from the normal aging process, in which the tissue gradually loses its natural water and elasticity, causing the degenerated disc to shrink and possibly rupture.
• Intervertebral disc injuries and degeneration are frequently treated by replacing or augmenting the existing disc material. Current methods and instrumentation used for treating the disc require a relatively large hole to be cut in the disc annulus to allow introduction of the implant. After the implantation, the large hole in the annulus must be plugged, sewn closed, or other wise blocked to avoid allowing the implant to be expelled from the disc. Besides weakening the annular tissue, creation of the large opening and the subsequent repair adds surgical time and cost. A need exists for devices, instrumentation, and methods for implanting an intervertebral implant using minimally invasive surgical techniques.
SUMMARY
• In one embodiment, a method of augmenting a nucleus pulposus of an intervertebral disc comprises forming a first opening in an annulus of the intervertebral disc and forming a second opening in the annulus of the intervertebral disc. The method further comprises providing a space creation instrument including an expandable spacing device and introducing the spacing device through the first opening and into the nucleus pulposus. The method further comprises introducing a material delivery instrument through the second opening and into the nucleus pulposus and expanding the spacing device to create a space within the nucleus pulposus. The method also comprises injecting a biocompatible material from the material delivery instrument and into the space within the nucleus pulposus.
• In another embodiment, a system for augmenting a nucleus of an intervertebral disc comprises a first cannula adapted for accessing a nucleus pulposus of the intervertebral disc and a second cannula adapted for accessing the nucleus pulposus of the intervertebral disc. The system further comprises a space creation instrument adapted to be received through the first cannula and including a spacing portion adapted to create a space in the nucleus pulposus of the intervertebral disc. The system further comprises a material delivery instrument adapted to be received through the second cannula and to carry a biocompatible material. The space created in the nucleus pulposus of the intervertebral disc with the space creation instrument is adapted to receive the biomaterial delivered to the space by the material delivery instrument through the second cannula.
• In another embodiment, a method for treating a nucleus pulposus of an intervertebral disc comprising creating a first opening to access the intervertebral disc and creating a second opening to access the intervertebral disc. The method further comprises inserting a first space creation instrument having a first spacing device through the first opening and into the nucleus pulposus of the intervertebral disc and inserting a second space creation instrument having a second spacing device through the second opening to access the intervertebral disc. The method further comprises injecting a first biomaterial into the first spacing device to expand the first spacing device and injecting a second biomaterial into the second spacing device to expand the second spacing device. The expansion of the first and second spacing devices occur without removing a portion of the nucleus pulposus.
• Additional embodiments are included in the attached drawings and the description provided below.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a sagittal view of a section of a vertebral column.
• FIGS. 2-5 are a sequence of views of an intervertebral disc treatment including accessing the nucleus, inserting an expandable device, expanding the expandable device to create a space, and filling the space.
• FIGS. 6-7 are sequence views of an intervertebral disc treatment according to another embodiment of the present disclosure.
• FIGS. 8-9 are sequence views of an intervertebral disc treatment according to another embodiment of the present disclosure.
• FIGS. 10-11 are alternative intervertebral disc treatments according to other embodiments of the present disclosure.
• FIGS. 12-13 are sequence views of an intervertebral disc treatment according to another embodiment of the present disclosure.
• FIGS. 14-15 are sequence views of an intervertebral disc treatment according to another embodiment of the present disclosure.
• FIGS. 16-17 are sequence views of an intervertebral disc treatment according to another embodiment of the present disclosure.
DETAILED DESCRIPTION
• The present disclosure relates generally to devices, methods and apparatus for augmenting an intervertebral disc, and more particularly, to methods and instruments for minimally invasive access procedures. For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments, or examples, illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates.
• Referring first toFIG. 1, thereference numeral10 refers to a vertebral joint section or a motion segment of a vertebral column. Thejoint section10 includes adjacentvertebral bodies12,14. Thevertebral bodies12,14 includeendplates16,18, respectively. An intervertebral disc space20 is located between theendplates16,18, and anannulus22 surrounds the space20. In a healthy joint, the space20 contains a nucleus pulposus24.
• Referring now toFIGS. 2-5, in this embodiment, thenucleus24 may be accessed by inserting acannula30 into the patient and locating the cannula at or near theannulus22. An accessinginstrument32, such as a trocar needle or a K-wire is inserted through thecannula30 and used to penetrate theannulus22, creating anannular opening33. This accessing procedure may be repeated at another position on theannulus22 using acannula34 to create anannular opening35. With theopenings33,35 created, the accessinginstrument32 may be removed and thecannulae30,34 left in place to provide passageway for additional instruments.
• In this embodiment, the nucleus is accessed using a posterior bilateral approach. In alternative embodiments, the annulus may be accessed with a lateral approach, an anterior approach, a trans-pedicular/vertebral endplate approach or any other suitable nucleus accessing approach. Although a bilateral approach is described, a unilateral or multi-lateral approach may be suitable. In another alternative embodiment, thenucleus24 may be accessed through one the ofvertebral bodies12,14 and through itsrespective endplate16,18. Thus, a suitable bilateral approach to nucleus augmentation may involve a combination approach including an annulus access opening and an endplate access opening.
• It is understood that any cannulated instrument including a guide needle or a trocar sleeve may be used to guide the accessing instrument.
• In this embodiment, the natural nucleus, or what remains of it after natural disease or degeneration, may remain intact with no tissue removed. In alternative embodiments, partial or complete nucleotomy procedures may be performed.
• As shown inFIG. 3, aspace creating device36 having acatheter portion38 and aspacing portion40 may be inserted through thecannula30 and theannular opening33 into thenucleus24. In this embodiment, thespacing portion40 is an expandable device such as a balloon which may be formed of elastic or non-elastic materials. The balloon can be of various shapes including conical, spherical, square, long conical, long spherical, long square, tapered, stepped, dog bone, offset, or combinations thereof. Balloons can be made of various polymeric materials such as polyethylene terephthalates, polyolefins, polyurethanes, nylon, polyvinyl chloride, silicone, polyetheretherketone, polylactide, polyglycolide, poly(lactide-co-glycoli-de), poly(dioxanone), poly(.epsilon.-caprolactone), poly(hydroxylbutyrate), poly(hydroxylvalerate), tyrosine-based polycarbonate, polypropylene fumarate or combinations thereof. Additionally, the expandable device may be molded or woven.
• In an alternative embodiment, the spacing portion may be mechanical instrument such as a probe or a tamp. A mechanically actuated deformable or expandable instrument which may deform via hinges, springs, shape memory material, etc. may also be used as a spacing portion. In some embodiments, the passage of the spacing portion may be aided with a more rigid guide needle or cannula which will accompany the spacing portion through the cannula and the annulus opening. This guide may be removed after the spacing portion is located within thenucleus24.
• As also shown inFIG. 3, adelivery instrument42 may be passed through thecannula34, through theannular opening35, and into thenucleus24. Thedelivery instrument42 may be an injection needle or other material delivery instrument and may be blunt to avoid puncture or damage to thespacing portion40.
• Referring now toFIG. 4, aninflation medium44 may be pressurized and injected or otherwise passed through thecatheter portion38 of thespace creating device36 to pressurize and inflate thespacing portion40. Theinflation medium44 may be a saline and/or radiographic contrast medium such as sodium diatrizoate solution sold under the trademark Hypaque® by Amersham Health, a division of GE Healthcare (Amersham, UK). Theinflation medium44 may be injected under pressure supplied by a hand, electric, or other type of powered pressurization device. The internal balloon pressure may be monitored with a well known pressure gauge. The rate of inflation and the pattern, size, or shape of the spacingportion40 can be varied between patients depending on disc condition. A control device for controlling inflation and dispensing of material is described in further detail in U.S. patent application Ser. No. ______, entitled “DEVICES, APPARATUS, AND METHODS FOR IMPROVED DISC AUGMENTATION, (Attorney Docket No. 31132.512) filed concurrently herewith and incorporated by reference herein.
• As the spacingportion40 is gradually inflated, aspace46 is created in the nucleus tissue with the surrounding nucleus tissue becoming displaced or stretched. The inflation may also cause the intradiscal pressure to increase. Both the pressure increase and the direct expansion of theportion40 may cause theendplates16,18 to distract. A pressure gauge and/or a pressure limiter may be used to avoid over inflation or excessive injection.
• In an alternative embodiment, the space creating portion may be disposed within theannular opening33 such that as the space creating portion is expanded, the opening becomes stretched or dilated by the space creating device.
• After thespace46 is created, thespace creating portion40 is deflated leaving thespace46 to be filled by abiocompatible material48 injected from thedelivery instrument42. The injection of the material48 may be facilitated by using a pressurization device and monitoring gauge. Thematerial48 may be injected after thespace creating portion40 has been deflated and removed or may be injected while thespace creating portion40 is being deflated and removed. For example, thebiomaterial48 may become increasingly pressurized while the pressure in thespace creating portion40 is lowered. In some procedures, thematerial48 may be injected before thespace creating portion40 is removed.
• Examples ofbiocompatible materials48 which may be used for disc augmentation include natural or synthetic and resorbable or non-resorbable materials. Natural materials include various forms of collagen that are derived from collagen-rich or connective tissues such as an intervertebral disc, fascia, ligament, tendon, skin, or demineralized bone matrix. Material sources include autograft, allograft, xenograft, or human-recombinant origin materials. Natural materials also include various forms of polysaccharides that are derived from animals or vegetation such as hyaluronic acid, chitosan, cellulose, or agar. Other natural materials include other proteins such as fibrin, albumin, silk, elastin and keratin. Synthetic materials include various implantable polymers or hydrogels such as silicone, polyurethane, silicone-polyurethane copolymers, polyolefin, polyester, polyacrylamide, polyacrylic acid, polyvinyl alcohol, polyethylene oxide, polyethylene glycol, polylactide, polyglycolide, poly(lactide-co-glycolide), poly(dioxanone), poly(.epsilon.-caprolactone), poly(hydroxylbutyrate), poly(hydroxylvalerate), tyrosine-based polycarbonate, polypropylene fumarate or combinations thereof. Suitable hydrogels may include poly(vinyl alcohol), poly(acrylic acids), poly(methacrylic acids), copolymers of acrylic acid and methacrylic acid, poly(acrylonitrile-acrylic acid), polyacrylamides, poly(N-vinyl-2-pyrrolidone), polyethylene glycol, polyethyleneoxide, polyacrylates, poly(2-hydroxy ethyl methacrylate), copolymers of acrylates with N-vinyl pyrrolidone, N-vinyl lactams, polyurethanes, polyphosphazenes, poly(oxyethylene)-poly(oxypropylene) block polymers, poly(oxyethylene)-poly(oxypropylene) block polymers of ethylene diamine, poly(vinyl acetate), and sulfonated polymers, polysaccharides, proteins, and combinations thereof.
• The selected biocompatible material may be curable or polymerizable in situ. The biocompatible material may transition from a flowable to a non-flowable state shortly after injection. One way to achieve this transition is by adding a crosslinking agent to the biomaterial before, during, or after injection. The biocompatible material in its final state may be load-bearing, partially load-bearing, or simply tissue augmenting with minimal or no load-bearing properties.
• Proteoglycans may also be included in the injectablebiocompatible material48 to attract and/or bind water to keep thenucleus24 hydrated. Regnerating agents may also be incorporated into the biocompatible material. An exemplary regenerating agent includes a growth factor. The growth factor can be generally suited to promote the formation of tissues, especially of the type(s) naturally occurring as components of an intervertebral disc. For example, the growth factor can promote the growth or viability of tissue or cell types occurring in the nucleus pulposus, such as nucleus pulposus cells and chondrocytes, as well as space filling cells, such as fibroblasts and connective tissue cells, such as ligament and tendon cells. Alternatively or in addition, the growth factor can promote the growth or viability of tissue types occurring in the annulus fibrosis, as well as space filling cells, such as fibroblasts and connective tissue cells, such as ligament and tendon cells. An exemplary growth factor can include transforming growth factor-β (TGF-β) or a member of the TGF-β superfamily, fibroblast growth factor (FGF) or a member of the FGF family, platelet derived growth factor (PDGF) or a member of the PDGF family, a member of the hedgehog family of proteins, interleukin, insulin-like growth factor (IGF) or a member of the IGF family, colony stimulating factor (CSF) or a member of the CSF family, growth differentiation factor (GDF), cartilage derived growth factor (CDGF), cartilage derived morphogenic proteins (CDMP), bone morphogenetic protein (BMP), or any combination thereof. In particular, an exemplary growth factor includes transforming growth factor P protein, bone morphogenetic protein, fibroblast growth factor, platelet-derived growth factor, insulin-like growth factor, or any combination thereof.
• Therapeutic or biological agents may also be incorporated into the biomaterial. An exemplary therapeutic or biological agent can include a soluble tumor necrosis factor α-receptor, a pegylated soluble tumor necrosis factor α-receptor, a monoclonal antibody, a polyclonal antibody, an antibody fragment, a COX-2 inhibitor, a metalloprotease inhibitor, a glutamate antagonist, a glial cell derived neurotrophic factor, a B2 receptor antagonist, a substance P receptor (NK1) antagonist, a downstream regulatory element antagonistic modulator (DREAM), iNOS, a inhibitor of tetrodotoxin (TTX)-resistant Na+-channel receptor subtypes PN3 and SNS2, an inhibitor of interleukin, a TNF binding protein, a dominant-negative TNF variant, Nanobodies™, a kinase inhibitor, or any combination thereof.
• These regenerating, therapeutic, or biological agents may promote healing, repair, regeneration and/or restoration of the disc, and/or facilitate proper disc function. Additives appropriate for use in the claimed invention are known to persons skilled in the art, and may be selected without undue experimentation.
• After thebiocompatible material48 is injected, thedelivery instrument42 may be removed from thecannula34. If the selectedbiocompatible material48 is curable in situ, theinstrument42 may be removed during or after curing to minimize leakage. Theopenings33,35 may be small enough, for example less than 3 mm, that they will close or close sufficiently that the injectedbiocompatible material48 will remain within the annulus. The use of an annulus closure device such as a suture, a plug, or a material sealant is optional. Thecannulae30,34 may be removed and the minimally invasive surgical incision closed.
• Any of the steps of the method including expansion of thespace creating portion40 and filling thespace46 may be monitored and guided with the aid of imaging methods such as fluoroscopy, x-ray, computed tomography, magnetic resonance imaging, and/or image guided surgical technology such as a Stealth Station™ surgical navigation system (Medtronic, Inc., Minneapolis, Minn.) or a BrainLab system (Heimstetten, Germany).
• In an alternative embodiment, the space creating portion may be detachable from the catheter portion and may remain in thenucleus24 as an implant. In this alternative, the biocompatible material may be injected directly into the space creating portion.
• Referring now toFIGS. 6-7, in this embodiment, thenucleus24 may be accessed by inserting acannula50 into the patient and locating the cannula at or near theannulus22. As described above, an accessing instrument is inserted through thecannula50 and used to penetrate theannulus22, creating anannular opening53. This accessing procedure may be repeated at another position on theannulus22 using acannula54 to create anannular opening55. With theopenings53,55 created, the accessing instrument may be removed and thecannulae50,54 left in place to provide bilateral passageways for additional instruments. In this embodiment, the natural nucleus, or what remains of it after natural disease or degeneration, may remain intact with no tissue removed. In alternative embodiments, partial or complete nucleotomy procedures may be performed.
• As shown inFIG. 6, aspace creating device56 having acatheter portion58 and aspacing portion60 may be inserted through thecannula50 and theannular opening53 into thenucleus24. In this embodiment, the spacing portion is an expandable device such as a balloon which may be formed of elastic or non-elastic materials. The characteristics of the balloon may be the same or similar to those described above. The spacing portion may be inflated and removed as described in further detail in U.S. patent application Ser. No. 10/314,396 (“the '396 application”) which is incorporated herein by reference. Thespace61 created by the spacing portion may be filled with abiocompatible material62 using thecannula54 through thebilateral opening55 in a manner similar to that described above forFIGS. 2-5 or alternatively, using thesame cannula50 and theopening53 in a manner similar to that described in the '396 application. The procedure of creating a space in thenucleus24 may be repeated in another location of the nucleus using theannular opening55 to pass a space creating device for creating a second space to be filled with a biocompatible material. This procedure may be substantially similar to that described above for creating and fillingspace61.
• Referring now toFIGS. 8-9, in this embodiment, thenucleus24 may be accessed by inserting acannula70 into the patient and locating the cannula at or near theannulus22. As described above, an accessing instrument is inserted through thecannula70 and used to penetrate theannulus22, creating anannular opening73. This accessing procedure may be repeated at another position on theannulus22 using acannula74 to create anannular opening75. With theopenings73,75 created, the accessing instrument may be removed and thecannulae70,74 left in place to provide bilateral passageways for additional instruments. In this embodiment, the natural nucleus, or what remains of it after natural disease or degeneration, may remain intact with no tissue removed. In alternative embodiments, partial or complete nucleotomy procedures may be performed.
• As shown inFIG. 8, aspace creating device76 having acatheter portion78 and aspacing portion80 may be inserted through thecannula70 and theannular opening73 into thenucleus24. In this embodiment, the spacing portion is an expandable device such as a balloon which may be formed of elastic or non-elastic materials. The characteristics of the balloon may be the same or similar to those described above. The spacingportion80 may be pressurized and filled with abiocompatible material82 as described in further detail in the '396 application. In this embodiment, the filledspacing portion80 may be detached and left within thenucleus pulposus24 as an implant. The procedure of creating a space in thenucleus24 may be repeated in another location of the nucleus using theannular opening55 to pass a spacing portion for creating a second space, filling the spacing portion with a biocompatible material, and detaching the second spacing portion. This procedure may be substantially similar to the procedure for filling the spacingportion80. In an alternative embodiment, the spacing portion may be filled with a biocompatible material using thecannula74 and thebilateral opening75 in a manner similar to that described above forFIGS. 2-5. This delivery of material through thebilateral opening75 may occur either before or after the spacing portion is detached from the catheter portion of the space creating device.
• Referring now toFIGS. 10 and 11, spacing portions similar to those described in the previous embodiments may be preformed in various shapes, such as triangular (FIG. 10) or capsular (FIG. 11), to achieve patient-specific goals including compensating for unique nucleus degradation or patient-tailored endplate distraction.
• Referring now toFIGS. 12 and 13, in this embodiment, thenucleus24 may be accessed by inserting acannula90 into the patient and locating the cannula at or near theannulus22. As described above, an accessing instrument is inserted through thecannula90 and used to penetrate theannulus22, creating anannular opening93. This accessing procedure may be repeated at another position on theannulus22 using acannula94 to create anannular opening95. With theopenings93,95 created, the accessing instrument may be removed and thecannulae90,94 left in place to provide bilateral passageways for additional instruments. In this embodiment, the natural nucleus, or what remains of it after natural disease or degeneration, may remain intact with no tissue removed. In alternative embodiments, partial or complete nucleotomy procedures may be performed.
• As shown inFIG. 12, aspace creating device96 having acatheter portion98 and aspacing portion100 may be inserted through thecannula90 and theannular opening93 into thenucleus24. In this embodiment, thespacing portion100 is an expandable device such as a balloon which may be formed of elastic or non-elastic materials. The characteristics of the balloon may be the same or similar to those described above. The balloon may be shaped to fit along the inner contour of theannulus22. Thespacing portion100 may be pressurized, filled, and detached as described above. Thespacing portion100 may be filled with abiocompatible material102 using thecannula94 and thebilateral opening95 in a manner similar to that described above forFIGS. 2-5 or using thesame cannula90 and theopening93 in a manner similar to that described in the '396 application. The procedure of creating a space in thenucleus24 along theannulus22 may be repeated in another location of the nucleus using theannular opening55 to pass a space creating device for creating a second implant to be filled with a biocompatible material. This procedure may be substantially similar to that described above for creating and fillingspacing portion100. The implant created by the filledspacing portion100 and its bilateral counterpart may be contoured to fit along an interior segment ofannulus22. The resulting implant may support a weakened annulus or reinforce a ruptured annulus to reduce or prevent nucleus herniation. The biocompatible material may be selected to optimize support and flexibility.
• Referring now toFIGS. 14 and 15, in this embodiment, thenucleus24 may be accessed by inserting acannula110 into the patient and locating the cannula at or near theannulus22. As described above, an accessing instrument is inserted through thecannula110 and used to penetrate theannulus22, creating an annular opening113. This accessing procedure may be repeated at another position on theannulus22 using acannula114 to create anannular opening115. With theopenings113,115 created, the accessing instrument may be removed and thecannulae110,114 left in place to provide bilateral passageways for additional instruments. In this embodiment, the natural nucleus, or what remains of it after natural disease or degeneration, may remain intact with no tissue removed. In alternative embodiments, partial or complete nucleotomy procedures may be performed.
• As shown inFIG. 14, annulus contoured spacingportions116,118 may be inserted, detached, and filled as described above inFIG. 12. The resulting implant may support a weakened annulus or reinforce a ruptured annulus to reduce or prevent nucleus herniation. The biocompatible filling material may be selected to optimize support and flexibility. These annulus reinforcingspacing portions116,118 may be used in conjunction with the more centralized nucleus spacing procedures described inFIGS. 2-11. In this embodiment, an additional spacing portion may be inserted through the filledspacing portions116,118 and expanded within thenucleus24 to create aspace120. Thespace120 may be filled with abiomaterial122. More spacing portions may be inserted to create additional filled spaces in thenucleus24. The use of annular spacing portions in conjunction with more centralized spacing portions may help to prevent the more centralized biomaterial and the natural nucleus tissue from migrating through annular defects or openings. The biomaterials selected for filling the various spaces and spacing portions may be the same or different depending upon the desired result.
• In an alternative embodiment, a delivery instrument may be inserted through the spacingportions116,118 to deposit a biocompatible material directly into thenucleus24 without creating an additional space within the nucleus. In this embodiment, the spacing portions serve to block migration or expulsion of the biocompatible material through the annulus, however the material may be more dispersed within the nucleus rather than concentrated in a pre-formed space.
• Referring now toFIGS. 16-17, in this embodiment, a substantially similar method of nucleus augmentation as the procedure described above forFIGS. 14-15 may be performed. In this embodiment, however, as described inFIGS. 8-9, spacingportions130,132 for creating the more centralized nucleus spaces may be detached to remain in the nucleus tissue as implants.
• Although the instruments and implants described are suitable for intervertebral applications, it is understood that the same implants and instruments may be modified for use in other regions including an interspinous region or a bone cavity. Furthermore, the instruments and implants of this disclosure may be incorporated in certain aspects into an intervertebral prosthesis device such as a motion preserving artificial disc.
• Although only a few exemplary embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this disclosure. Accordingly, all such modifications and alternative are intended to be included within the scope of the invention as defined in the following claims. Those skilled in the art should also realize that such modifications and equivalent constructions or methods do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure. It is understood that all spatial references, such as “horizontal,” “vertical,” “top,” “upper,” “lower,” “bottom,” “left,” “right,” “anterior,” “posterior,” “superior,” “inferior,” “upper,” and “lower” are for illustrative purposes only and can be varied within the scope of the disclosure. In the claims, means-plus-function clauses are intended to cover the elements described herein as performing the recited function and not only structural equivalents, but also equivalent elements.

Claims (33)

1. A method of augmenting a nucleus pulposus of an intervertebral disc, the method comprising:

forming a first opening in an annulus of the intervertebral disc;

forming a second opening in the annulus of the intervertebral disc;

providing a space creation instrument including an expandable spacing device;

introducing the spacing device through the first opening and into the nucleus pulposus;

introducing a material delivery instrument through the second opening and into the nucleus pulposus;

expanding the spacing device to create a space within the nucleus pulposus; and

injecting a biocompatible material from the material delivery instrument and into the space within the nucleus pulposus.

2. The method ofclaim 1 wherein none of the nucleus pulposus is removed prior to expanding the spacing device.

3. The method ofclaim 1 further comprising expanding the spacing device to dilate the annulus.

4. The method ofclaim 1 wherein the spacing device comprises an inflatable balloon.

5. The method ofclaim 4 wherein the balloon comprises multiple chambers.

6. The method ofclaim 1 wherein the spacing device is mechanically actuated.

7. The method ofclaim 1 wherein the step of introducing the spacing device further comprises introducing a guide member adjacent to the spacing device.

8. The method ofclaim 1 wherein the step of introducing a material delivery instrument further comprises guiding the introduction of the material delivery instrument with an imaging system to direct the material delivery instrument to the spacing device.

9. The method ofclaim 8 wherein the imaging system is fluoroscopic.

10. The method ofclaim 1 wherein the step of expanding the spacing device to create a space within the nucleus pulposus comprises pressurizing an inflation medium.

11. The method ofclaim 1 wherein the step of expanding the space creation device to create a space within the nucleus pulposus comprises compressing the nucleus pulposus.

12. The method ofclaim 1 wherein the first and second openings are bilateral posterior openings.

13. The method ofclaim 1 wherein the step of injecting a biocompatible material from the material delivery instrument further comprises monitoring the injection of the biocompatible material with an imaging system to avoid overfilling the space.

14. The method ofclaim 1 wherein the step of expanding the spacing device further comprises distracting a pair of vertebral endplates adjacent to the intervertebral disc.

15. The method ofclaim 1 further comprising detaching the spacing device from the space creation instrument within the space in the nucleus pulposus.

16. The method ofclaim 15 wherein the step of injecting a biocompatible material from the material delivery instrument includes filling the spacing device within the space in the nucleus pulposus.

17. The method ofclaim 1 further comprising collapsing the spacing device as the biomaterial is injected into the space within the nucleus pulposus.

18. The method ofclaim 1 further comprising withdrawing the spacing device from the nucleus pulposus.

19. A system for augmenting a nucleus pulposus of an intervertebral disc, the system comprising:

a first cannula adapted for accessing a nucleus pulposus of the intervertebral disc;

a second cannula adapted for accessing the nucleus pulposus of the intervertebral disc;

a space creation instrument adapted for passage through the first cannula and including a spacing portion adapted to create a space in the nucleus pulposus of the intervertebral disc; and

a material delivery instrument adapted for passage through the second cannula and to carry a biocompatible material,

wherein the space created in the nucleus pulposus of the intervertebral disc with the spacing portion receives the biocompatible material delivered by the material delivery instrument through the second cannula.

20. The system ofclaim 19 wherein at least one of the cannulae is directed through an annulus of the intervertebral disc to the nucleus pulposus.

21. The system ofclaim 19 wherein at least one of the cannulae is directed through an endplate of a vertebral body adjacent to the intervertebral disc.

22. The system ofclaim 19 wherein none of the nucleus pulposus is removed through the first or second cannulae.

23. The system ofclaim 19 further comprising an accessing instrument adapted to pass through the first cannula to puncture an annulus of the intervertebral disc.

24. The system ofclaim 19 further comprising a gauge for monitoring pressure in the spacing portion.

25. A method for treating a nucleus pulposus of an intervertebral disc, the method comprising:

creating a first opening to access the intervertebral disc;

creating a second opening to access the intervertebral disc;

inserting a first space creation instrument having a first spacing device through the first opening and into the nucleus pulposus of the intervertebral disc;

inserting a second space creation instrument having a second spacing device through the second opening to access the intervertebral disc;

injecting a first biomaterial into the first spacing device to expand the first spacing device; and

injecting a second biomaterial into the second spacing device to expand the second spacing device,

wherein the expansion of the first and second spacing devices occur without removing a portion of the nucleus pulposus.

26. The method ofclaim 25 wherein the first opening is in an annulus of the intervertebral disc.

27. The method ofclaim 25 further comprising detaching the first spacing device from the first space creation instrument.

28. The method ofclaim 25 wherein the first biomaterial is the same as the second biomaterial.

29. The method ofclaim 25 wherein the first spacing device conforms to an annulus of the intervertebral disc.

30. The method ofclaim 29 further comprising inserting a third spacing device into the nucleus pulposus of the intervertebral disc and expanding the third spacing device with a third biomaterial

31. The method ofclaim 30 wherein the third spacing device is inserted through the first spacing device.

32. The method ofclaim 25 wherein at least one of the first or second biomaterials is curable in situ.

33. The method ofclaim 25 further comprising inserting a material delivery instrument through the first spacing device and injecting a third biomaterial into the nucleus pulposus.

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