US20110213418A1 - Multi-chamber expandable interspinous process spacer - Google Patents

Abstract

An expandable interspinous process spacer is disclosed that includes at least two chambers, one disposed within the other. Each of the at least two chambers can receive an injectable biocompatible material, which advantageously may have different material properties such as hardness. Further, the expandable interspinous process spacer can be changed from a deflated configuration to an inflated configuration. In the inflated configuration, the expandable interspinous process spacer can engage and support a superior spinous process and an inferior spinous process.

Description

• This application is a continuation of co-pending U.S. patent application Ser. No. 12/795,883, filed Jun. 8, 2010 which is a divisional of U.S. patent application Ser. No. 11/413,587, filed 28 Apr. 2006, now abandoned, each of which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
• The present disclosure relates generally to orthopedics and orthopedic surgery. More specifically, the present disclosure relates to devices used to support adjacent spinous processes.
BACKGROUND
• In human anatomy, the spine is a generally flexible column that can take tensile and compressive loads. The spine also allows bending motion and provides a place of attachment for keels, muscles and ligaments. Generally, the spine is divided into three sections: the cervical spine, the thoracic spine and the lumbar spine. The sections of the spine are made up of individual bones called vertebrae. Also, the vertebrae are separated by intervertebral discs, which are situated between adjacent vertebrae.
• The intervertebral discs function as shock absorbers and as joints. Further, the intervertebral discs can absorb the compressive and tensile loads to which the spinal column may be subjected. At the same time, the intervertebral discs can allow adjacent vertebral bodies to move relative to each other a limited amount, particularly during bending, or flexure, of the spine. Thus, the intervertebral discs are under constant muscular and/or gravitational pressure and generally, the intervertebral discs are the first parts of the lumbar spine to show signs of deterioration.
• Facet joint degeneration is also common because the facet joints are in almost constant motion with the spine. In fact, facet joint degeneration and disc degeneration frequently occur together. Generally, although one may be the primary problem while the other is a secondary problem resulting from the altered mechanics of the spine, by the time surgical options are considered, both facet joint degeneration and disc degeneration typically have occurred. For example, the altered mechanics of the facet joints and/or intervertebral disc may cause spinal stenosis, degenerative spondylolisthesis, and degenerative scoliosis.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a lateral view of a portion of a vertebral column;
• FIG. 2 is a lateral view of a pair of adjacent vertebrae;
• FIG. 3 is a top plan view of a vertebra;
• FIG. 4 is a plan view of a first multi-chamber expandable interspinous process spacer in a deflated configuration;
• FIG. 5 is a plan view of the first multi-chamber expandable interspinous process spacer in an inflated configuration;
• FIG. 6 is a plan view of the first multi-chamber expandable interspinous process spacer in an inflated configuration with a tether installed there around;
• FIG. 7 is a plan view of a second multi-chamber expandable interspinous process spacer in a deflated configuration;
• FIG. 8 is a plan view of the second multi-chamber expandable interspinous process spacer in an inflated configuration;
• FIG. 9 is a plan view of the second multi-chamber expandable interspinous process spacer in an inflated configuration with a tether installed there around;
• FIG. 10 is a plan view of a third multi-chamber expandable interspinous process spacer in a deflated configuration;
• FIG. 11 is a plan view of the third multi-chamber expandable interspinous process spacer in an inflated configuration;
• FIG. 12 is a plan view of the third multi-chamber expandable interspinous process spacer in an inflated configuration with a tether installed there around;
• FIG. 13 is a plan view of a fourth multi-chamber expandable interspinous process spacer in a deflated configuration;
• FIG. 14 is a plan view of the fourth multi-chamber expandable interspinous process spacer in an inflated configuration;
• FIG. 15 is a plan view of the fourth multi-chamber expandable interspinous process spacer in an inflated configuration with a tether installed there around;
• FIG. 16 is a plan view of a fifth multi-chamber expandable interspinous process spacer in a deflated configuration;
• FIG. 17 is a plan view of the fifth multi-chamber expandable interspinous process spacer in an inflated configuration;
• FIG. 18 is a plan view of the fifth multi-chamber expandable interspinous process spacer in an inflated configuration with a tether installed there around;
• FIG. 19 is a plan view of a sixth multi-chamber expandable interspinous process spacer in a deflated configuration;
• FIG. 20 is a plan view of the sixth multi-chamber expandable interspinous process spacer in an inflated configuration;
• FIG. 21 is a plan view of the sixth multi-chamber expandable interspinous process spacer in an inflated configuration with a tether installed there around; and
• FIG. 22 is a flow chart illustrating a method of treating a spine.
DETAILED DESCRIPTION OF THE DRAWINGS
• A multi-chamber expandable interspinous process spacer or brace is disclosed and can include at least two chambers. Each of the at least two chambers can receive an injectable biocompatible material. Further, the multi-chamber expandable interspinous process brace can be moved between a deflated configuration and an inflated configuration. In the inflated configuration, the multi-chamber expandable interspinous process brace can engage and support a superior spinous process and an inferior spinous process.
• In another embodiment, a method of treating a spine is disclosed and can include installing a multi-chamber expandable interspinous process brace between a superior spinous process and an inferior spinous process. The method can also include inflating at least two chambers within the multi-chamber expandable interspinous process brace to support the superior spinous process and the inferior spinous process.
• In still another embodiment, a method of treating a spine is disclosed and can include distracting a superior spinous process and an inferior spinous process. Also, the method can include installing a multi-chamber expandable interspinous process brace between a superior spinous process and an inferior spinous process. Moreover, the method can include inflating at least two chambers within the multi-chamber expandable interspinous process brace to support the superior spinous process and the inferior spinous process.
• In yet another embodiment, a kit for field use is disclosed and can include a multi-chamber expandable interspinous process brace that can have at least two chambers configured to receive an injectable biocompatible material. The kit can also include an injectable biocompatible material.
• In still yet another embodiment, a kit for field use is disclosed and can include a multi-chamber expandable interspinous process brace that can include at least two chambers configured to receive an injectable biocompatible material. Additionally, the kit can include an injectable biocompatible material and a tether that can circumscribe the multi-chamber expandable interspinous process brace, a superior spinous process, and an inferior spinous process.
• Description of Relevant Anatomy
• Referring initially toFIG. 1, a portion of a vertebral column, designated100, is shown. As depicted, thevertebral column100 includes alumbar region102, asacral region104, and a coccygeal region106. As is known in the art, thevertebral column100 also includes a cervical region and a thoracic region. For clarity and ease of discussion, the cervical region and the thoracic region are not illustrated.
• As shown inFIG. 1, thelumbar region102 includes afirst lumbar vertebra108, a secondlumbar vertebra110, athird lumbar vertebra112, afourth lumbar vertebra114, and afifth lumbar vertebra116. Thesacral region104 includes asacrum118. Further, the coccygeal region106 includes acoccyx120.
• As depicted inFIG. 1, a first intervertebrallumbar disc122 is disposed between the firstlumbar vertebra108 and the secondlumbar vertebra110. A second intervertebrallumbar disc124 is disposed between the secondlumbar vertebra110 and the thirdlumbar vertebra112. A third intervertebrallumbar disc126 is disposed between the thirdlumbar vertebra112 and the fourthlumbar vertebra114. Further, a fourth intervertebrallumbar disc128 is disposed between the fourthlumbar vertebra114 and the fifthlumbar vertebra116. Additionally, a fifth intervertebrallumbar disc130 is disposed between the fifthlumbar vertebra116 and thesacrum118.
• In a particular embodiment, if one of the intervertebrallumbar discs122,124,126,128,130 is diseased, degenerated, damaged, or otherwise in need of repair, treatment of that intervertebrallumbar disc122,124,126,128,130 can be effected in accordance with one or more of the embodiments described herein.
• FIG. 2 depicts a detailed lateral view of two adjacent vertebrae, e.g., two of thelumbar vertebra108,110,112,114,116 shown inFIG. 1.FIG. 2 illustrates a superior vertebra200 and aninferior vertebra202. As shown, eachvertebra200,202 includes avertebral body204, a superiorarticular process206, atransverse process208, aspinous process210 and an inferiorarticular process212.FIG. 2 further depicts an intervertebral disc216 between the superior vertebra200 and theinferior vertebra202.
• Referring toFIG. 3, a vertebra, e.g., the inferior vertebra202 (FIG. 2), is illustrated. As shown, thevertebral body204 of theinferior vertebra202 includes acortical rim302 composed of cortical bone. Also, thevertebral body204 includescancellous bone304 within thecortical rim302. Thecortical rim302 is often referred to as the apophyseal rim or apophyseal ring. Further, thecancellous bone304 is softer than the cortical bone of thecortical rim302.
• As illustrated inFIG. 3, theinferior vertebra202 further includes afirst pedicle306, asecond pedicle308, afirst lamina310, and asecond lamina312. Further, avertebral foramen314 is established within theinferior vertebra202. Aspinal cord316 passes through thevertebral foramen314. Moreover, afirst nerve root318 and asecond nerve root320 extend from thespinal cord316.
• It is well known in the art that the vertebrae that make up the vertebral column have slightly different appearances as they range from the cervical region to the lumbar region of the vertebral column. However, all of the vertebrae, except the first and second cervical vertebrae, have the same basic structures, e.g., those structures described above in conjunction withFIG. 2 andFIG. 3. The first and second cervical vertebrae are structurally different than the rest of the vertebrae in order to support a skull.
Description of a First Embodiment of a Multi-Chamber Expandable Interspinous Process Brace
• Referring toFIG. 4 throughFIG. 6, a first embodiment of a multi-chamber expandable interspinous process brace is shown and is generally designated400. As shown, the multi-chamber expandableinterspinous process brace400 includes aninterior chamber402 and anexterior chamber404.
• In a particular embodiment, theinterior chamber402 can be generally elliptical. Alternatively, theinterior chamber402 can be generally spherical, generally pyramidal, generally conical, generally frustal, generally cubic, generally polyhedral, or a combination thereof. Theexterior chamber404 can be provided in a shape that can generally engage and/or stabilize at least one spinous process, such as, for example, the spinous processes of two adjacent vertebrae. In a particular embodiment, theexterior chamber404 can be generally H-shaped.
• Further, in a particular embodiment, thechambers402,404 can be made from one or more expandable biocompatible materials. For example, the materials can be silicones, polyurethanes, polycarbonate urethanes, polyethylene terephthalate, silicone copolymers, polyolefins, or any combination thereof. Also, thechambers402,404 can be non-porous or micro-porous, e.g., for venting purposes.
• As shown inFIG. 4, theinterior chamber402 can include afirst injection tube406. Further, theexterior chamber404 can include asecond injection tube408. Theinjection tubes406,408 can be used to provide an injectable biocompatible material to thechambers402,404. In a particular embodiment, each of theinterior chamber402 and theexterior chamber404 of the multi-chamber expandableinterspinous process brace400 can be expanded from a respective deflated configuration, shown inFIG. 4, to one of a plurality of inflated configurations, shown inFIG. 5, up to a maximum inflated configuration. Further, after theinterior chamber402 and theexterior chamber404 are inflated, or otherwise expanded, theinjection tubes406,408 can be removed, as depicted inFIG. 6.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace400 can include a first self-sealing valve (not shown) within theinterior chamber402, e.g., adjacent to thefirst injection tube406. Moreover, the multi-chamber expandableinterspinous process brace400 can include a second self-sealing valve (not shown) within theexterior chamber404, e.g., adjacent to thesecond injection tube408. The self-sealing valves can prevent thechambers402,404 from leaking material after thechambers402,404 are inflated and theinjection tubes406,408 are removed.
• As illustrated inFIG. 4 throughFIG. 6, theexterior chamber404 can include a superiorspinous process pocket410 and an inferiorspinous process pocket412. Further, a superior spinousprocess engagement structure420 can extend from theexterior chamber404 within the superiorspinous process pocket410. Also, an inferior spinousprocess engagement structure422 can extend from theexterior chamber404 within the inferiorspinous process pocket412. In a particular embodiment, each of the spinousprocess engagement structures420,422 can be one or more spikes, one or more teeth, a combination thereof, or some other structure configured to engage a spinous process.
• FIG. 4 throughFIG. 6 indicate that the multi-chamber expandableinterspinous process brace400 can be implanted between a superiorspinous process500 and an inferiorspinous process502. In a particular embodiment, thechambers402,404 can be inflated so theexterior chamber404 engages thespinous processes500,502. In a particular embodiment, when the multi-chamber expandableinterspinous process brace400 is properly installed and inflated between the superiorspinous process500 and the inferiorspinous process502, the superiorspinous process pocket410 can engage and support the superiorspinous process500. Further, the inferiorspinous process pocket412 can engage and support an inferiorspinous process502.
• More specifically, the superior spinousprocess engagement structure420 can extend slightly into and engage the superiorspinous process500. Also, the inferior spinousprocess engagement structure422 can extend slightly into and engage the inferiorspinous process502. Accordingly, the spinousprocess engagement structures420,422, the spinous process pockets410,412, or a combination thereof can substantially prevent the multi-chamber expandableinterspinous process brace400 from migrating with respect to thespinous processes500,502.
• Also, in a particular embodiment, the multi-chamber expandableinterspinous process brace400 can be movable between a deflated configuration, shown inFIG. 4, and one or more inflated configurations, shown inFIG. 5 andFIG. 6. In the deflated configuration, adistance512 between the superiorspinous process pocket410 and the inferiorspinous process pocket412 can be at a minimum. However, as one or more materials are injected into thechambers402,404, thedistance512 between the superiorspinous process pocket410 and the inferiorspinous process pocket412 can increase.
• Accordingly, the multi-chamber expandableinterspinous process brace400 can be installed between a superiorspinous process500 and an inferiorspinous process502. Further, the multi-chamber expandableinterspinous process brace400 can be expanded, e.g., by injecting one or more materials into thechambers402,404, in order to increase the distance between the superiorspinous process500 and the inferiorspinous process502.
• Alternatively, a distractor can be used to increase the distance between the superiorspinous process500 and the inferiorspinous process502 and the multi-chamber expandableinterspinous process brace400 can be expanded to support the superiorspinous process500 and the inferiorspinous process502. After the multi-chamber expandableinterspinous process brace400 is expanded accordingly, the distractor can be removed and the multi-chamber expandableinterspinous process brace400 can support the superiorspinous process500 and the inferiorspinous process502 to substantially prevent the distance between the superiorspinous process502 and the inferiorspinous process500 from returning to a pre-distraction value.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace400 can be injected with one or more injectable biocompatible materials that remain elastic after curing. Further, the injectable biocompatible materials can include polymer materials that remain elastic after curing. Also, the injectable biocompatible materials can include ceramics.
• For example, the polymer materials can include polyurethanes, polyolefins, silicones, silicone polyurethane copolymers, polymethylmethacrylate (PMMA), epoxies, cyanoacrylate, hydrogels, or a combination thereof. Further, the polyolefin materials can include polypropylenes, polyethylenes, halogenated polyolefins, or flouropolyolefins.
• The hydrogels can include polyacrylamide (PAAM), poly-N-isopropylacrylamine (PNIPAM), polyvinyl methylether (PVM), polyvinyl alcohol (PVA), polyethyl hydroxyethyl cellulose, poly(2-ethyl)oxazoline, polyethyleneoxide (PEO), polyethylglycol (PEG), polyacrylacid (PAA), polyacrylonitrile (PAN), polyvinylacrylate (PVA), polyvinylpyrrolidone (PVP), or a combination thereof.
• In a particular embodiment, the ceramics can include calcium phosphate, hydroxyapatite, calcium sulfate, bioactive glass, or a combination thereof. In an alternative embodiment, the injectable biocompatible materials can include one or more fluids such as sterile water, saline, or sterile air.
• In a particular embodiment, the hardness of the material used to inflate theinterior chamber402 can be less than or equal to the hardness of the material used to inflate theexterior chamber404, i.e., after the materials used to inflate theinterior chamber402 and theexterior chamber404 are cured. Alternatively, the viscosity of the material used to inflate theinterior chamber402 can be less than or equal to the viscosity of the material used to inflate theexterior chamber404. In a particular embodiment, certain or all of the injected materials can be cured or cross-linked in situ to form a solid interspinous process brace with non-uniform bulk properties.
• FIG. 6 indicates that atether600 can be installed around the multi-chamber expandableinterspinous process brace400, after the multi-chamber expandableinterspinous process brace400 is expanded as described herein. As shown, thetether600 can include aproximal end602 and adistal end604. In a particular embodiment, thetether600 can circumscribe the multi-chamber expandableinterspinous process brace400 and thespinous processes500,502. Further, theends602,604 of thetether600 can be brought together and one or more fasteners can be installed therethrough to connect theends602,604. Accordingly, thetether600 can be installed in order to prevent the distance between thespinous processes500,502 from substantially increasing beyond the distance provided by the multi-chamber expandableinterspinous process brace400 after it is expanded and to maintain engagement of the interspinous processes with the spinous process pockets410,412, theengagement structures420,422, or a combination thereof.
• In a particular embodiment, thetether600 can comprise a biocompatible elastomeric material that flexes during installation and provides a resistance fit against the inferior process. Further, thetether600 can comprise a substantially non-resorbable suture or the like.
Description of a Second Embodiment of a Multi-Chamber Expandable Interspinous Process Brace
• Referring toFIG. 7 throughFIG. 9, a second embodiment of a multi-chamber expandable interspinous process brace is shown and is generally designated700. As shown, the multi-chamber expandableinterspinous process brace700 includes aninterior chamber702 and anexterior chamber704.
• Theinterior chamber702 and theexterior chamber704 can be provided in a shape that can generally engage and/or stabilize at least one spinous process, such as, for example, the spinous processes of two adjacent vertebrae. In a particular embodiment, theinterior chamber702 can be generally H-shaped. Also, in a particular embodiment, theexterior chamber704 can be hollow and generally H-shaped. More specifically, theexterior chamber704 can be shaped to match the outer perimeter of theinterior chamber702.
• Further, in a particular embodiment, thechambers702,704 can be made from one or more expandable biocompatible materials. For example, the materials can be silicones, polyurethanes, polycarbonate urethanes, polyethylene terephthalate, silicone copolymers, polyolefins, or any combination thereof. Also, thechambers702,704 can be non-porous or micro-porous, e.g., for venting purposes.
• As shown inFIG. 7, theinterior chamber702 can include afirst injection tube706. Further, theexterior chamber704 can include asecond injection tube708. Theinjection tubes706,708 can be used to provide an injectable biocompatible material to thechambers702,704. In a particular embodiment, each of theinterior chamber702 and theexterior chamber704 of the multi-chamber expandableinterspinous process brace700 can be expanded from a respective deflated configuration, shown inFIG. 7, to one of a plurality of inflated configurations, shown inFIG. 8, up to a maximum inflated configuration. Further, after theinterior chamber702 and theexterior chamber704 are inflated, or otherwise expanded, theinjection tubes706,708 can be removed, as depicted inFIG. 9.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace700 can include a first self-sealing valve (not shown) within theinterior chamber702, e.g., adjacent to thefirst injection tube706. Moreover, the multi-chamber expandableinterspinous process brace700 can include a second self-sealing valve (not shown) within theexterior chamber704, e.g., adjacent to thesecond injection tube708. The self-sealing valves can prevent thechambers702,704 from leaking material after thechambers702,704 are inflated and theinjection tubes706,708 are removed.
• As illustrated inFIG. 7 throughFIG. 9, theexterior chamber704 can include a superiorspinous process pocket710 and an inferiorspinous process pocket712. Further, a superior spinousprocess engagement structure720 can extend from theexterior chamber704 within the superiorspinous process pocket710. Also, an inferior spinousprocess engagement structure722 can extend from theexterior chamber704 within the inferiorspinous process pocket712. In a particular embodiment, each of the spinousprocess engagement structures720,722 can be one or more spikes, one or more teeth, a combination thereof, or some other structure configured to engage a spinous process.
• FIG. 7 throughFIG. 9 indicate that the multi-chamber expandableinterspinous process brace700 can be implanted between a superiorspinous process800 and an inferiorspinous process802. In a particular embodiment, thechambers702,704 can be inflated so theexterior chamber704 engages thespinous processes800,802. In a particular embodiment, when the multi-chamber expandableinterspinous process brace700 is properly installed and inflated between the superiorspinous process800 and the inferiorspinous process802, the superiorspinous process pocket710 can engage and support the superiorspinous process800. Further, the inferiorspinous process pocket712 can engage and support an inferiorspinous process802.
• More specifically, the superior spinousprocess engagement structure720 can extend slightly into and engage the superiorspinous process800. Also, the inferior spinousprocess engagement structure722 can extend slightly into and engage the inferiorspinous process802. Accordingly, the spinousprocess engagement structures720,722, the spinous process pockets710,712, or a combination thereof can substantially prevent the multi-chamber expandableinterspinous process brace700 from migrating with respect to thespinous processes800,802.
• Also, in a particular embodiment, the multi-chamber expandableinterspinous process brace700 can be movable between a deflated configuration, shown inFIG. 7, and one or more inflated configurations, shown inFIG. 8 andFIG. 9. In the deflated configuration, adistance812 between the superiorspinous process pocket710 and the inferiorspinous process pocket712 can be at a minimum. However, as one or more materials are injected into thechambers702,704, thedistance812 between the superiorspinous process pocket710 and the inferiorspinous process pocket712 can increase.
• Accordingly, the multi-chamber expandableinterspinous process brace700 can be installed between a superiorspinous process800 and an inferiorspinous process802. Further, the multi-chamber expandableinterspinous process brace700 can be expanded, e.g., by injecting one or more materials into thechambers702,704, in order to increase the distance between the superiorspinous process800 and the inferiorspinous process802.
• Alternatively, a distractor can be used to increase the distance between the superiorspinous process800 and the inferiorspinous process802 and the multi-chamber expandableinterspinous process brace700 can be expanded to support the superiorspinous process800 and the inferiorspinous process802. After the multi-chamber expandableinterspinous process brace700 is expanded accordingly, the distractor can be removed and the multi-chamber expandableinterspinous process brace700 can support the superiorspinous process800 and the inferiorspinous process802 to substantially prevent the distance between the superiorspinous process802 and the inferiorspinous process800 from returning to a pre-distraction value.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace700 can be injected with one or more injectable biocompatible materials that remain elastic after curing. Further, the injectable biocompatible materials can include polymer materials that remain elastic after curing. Also, the injectable biocompatible materials can include ceramics.
• For example, the polymer materials can include polyurethanes, polyolefins, silicones, silicone polyurethane copolymers, polymethylmethacrylate (PMMA), epoxies, cyanoacrylates, hydrogels, or a combination thereof. Further, the polyolefin materials can include polypropylenes, polyethylenes, halogenated polyolefins, or flouropolyolefins.
• The hydrogels can include polyacrylamide (PAAM), poly-N-isopropylacrylamine (PNIPAM), polyvinyl methylether (PVM), polyvinyl alcohol (PVA), polyethyl hydroxyethyl cellulose, poly(2-ethyl)oxazoline, polyethyleneoxide (PEO), polyethylglycol (PEG), polyacrylacid (PAA), polyacrylonitrile (PAN), polyvinylacrylate (PVA), polyvinylpyrrolidone (PVP), or a combination thereof.
• In a particular embodiment, the ceramics can include calcium phosphate, hydroxyapatite, calcium sulfate, bioactive glass, or a combination thereof. In an alternative embodiment, the injectable biocompatible materials can include one or more fluids such as sterile water, saline, or sterile air.
• In a particular embodiment, the hardness of the material used to inflate theinterior chamber702 can be greater than or equal to the hardness of the material used to inflate theexterior chamber704, i.e., after the materials used to inflate theinterior chamber702 and theexterior chamber704 are cured. Alternatively, the viscosity of the material used to inflate theinterior chamber702 can be greater than or equal to the viscosity of the material used to inflate theexterior chamber704. In a particular embodiment, certain or all of the injected materials can be cured or cross-linked in situ to form a solid interspinous process brace with non-uniform bulk properties.
• FIG. 9 indicates that atether900 can be installed around the multi-chamber expandableinterspinous process brace700, after the multi-chamber expandableinterspinous process brace700 is expanded as described herein. As shown, thetether900 can include aproximal end902 and adistal end904. In a particular embodiment, thetether900 can circumscribe the multi-chamber expandableinterspinous process brace700 and thespinous processes800,802. Further, theends902,904 of thetether900 can be brought together and one or more fasteners can be installed therethrough to connect theends902,904. Accordingly, thetether900 can be installed in order to prevent the distance between thespinous processes800,802 from substantially increasing beyond the distance provided by the multi-chamber expandableinterspinous process brace700 after it is expanded and to maintain engagement of the interspinous processes with the spinous process pockets710,712, theengagement structures720,722, or a combination thereof.
• In a particular embodiment, thetether900 can comprise a biocompatible elastomeric material that flexes during installation and provides a resistance fit against the inferior process. Further, thetether900 can comprise a substantially non-resorbable suture or the like.
Description of a Third Embodiment of a Multi-Chamber Expandable Interspinous Process Brace
• Referring toFIG. 10 throughFIG. 12, a third embodiment of a multi-chamber expandable interspinous process brace is shown and is generally designated1000. As shown, the multi-chamber expandableinterspinous process brace1000 includes acentral chamber1002, asuperior chamber1004, and aninferior chamber1006.
• In a particular embodiment, thecentral chamber1002 can be generally horizontally elongated. Also, in a particular embodiment, thesuperior chamber1004 can be shaped similar to the top half of a letter H and theinferior chamber1006 can be shaped similar to the bottom half of a letter H. Together, thecentral chamber1002, thesuperior chamber1004, and theinferior chamber1006 can be provided in a shape that can generally engage and/or stabilize at least one spinous process, such as, for example, the spinous processes of two adjacent vertebrae. In a particular embodiment, together, thechambers1002,1004 and1006 can be generally H-shaped.
• Further, in a particular embodiment, thechambers1002,1004,1006 can be made from one or more expandable biocompatible materials. For example, the materials can be silicones, polyurethanes, polycarbonate urethanes, polyethylene terephthalate, silicone copolymers, polyolefins, or any combination thereof. Also, thechambers1002,1004,1006 can be non-porous or micro-porous, e.g., for venting purposes.
• As shown inFIG. 10, thecentral chamber1002 can include afirst injection tube1008. Thesuperior chamber1004 can include asecond injection tube1010 and theinferior chamber1006 can include athird injection tube1012. Theinjection tubes1008,1010,1012 can be used to provide one or more injectable biocompatible material to thechambers1002,1004,1006. In a particular embodiment, each of thecentral chamber1002, thesuperior chamber1004, and theinferior chamber1006 of the multi-chamber expandableinterspinous process brace1000 can be expanded from a respective deflated configuration, shown inFIG. 10, to one of a plurality of inflated configurations, shown inFIG. 11 andFIG. 12, up to a maximum inflated configuration. Further, after thechambers1002,1004,1006 are inflated, or otherwise expanded, theinjection tubes1008,1010,1012 can be removed, as depicted inFIG. 12.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace1000 can include a first self-sealing valve (not shown) within thecentral chamber1002, e.g., adjacent to thefirst injection tube1008. Moreover, the multi-chamber expandableinterspinous process brace1000 can include a second self-sealing valve (not shown) within thesuperior chamber1004, e.g., adjacent to thesecond injection tube1010. The multi-chamber expandableinterspinous process brace1000 can also include a third self-sealing valve (not shown) within theinferior chamber1006. The self-sealing valves can prevent thechambers1002,1004,1006 from leaking material after thechambers1002,1004,1006 are inflated and theinjection tubes1008,1010,1012 are removed.
• As illustrated inFIG. 10 throughFIG. 12, thesuperior chamber1004 can include a superiorspinous process pocket1014 and theinferior chamber1006 can include an inferiorspinous process pocket1016. Further, a superior spinousprocess engagement structure1020 can extend from thesuperior chamber1004 within the superiorspinous process pocket1014. Also, an inferior spinousprocess engagement structure1022 can extend from theinferior chamber1004 within the inferiorspinous process pocket1016. In a particular embodiment, each of the spinousprocess engagement structures1020,1022 can be one or more spikes, one or more teeth, a combination thereof, or some other structure configured to engage a spinous process.
• FIG. 10 throughFIG. 12 indicate that the multi-chamber expandableinterspinous process brace1000 can be implanted between a superiorspinous process1100 and aninferior spinous process1102. In a particular embodiment, thechambers1002,1004,1006 can be inflated so thesuperior chamber1004 engages the superiorspinous process1100 and theinferior chamber1006 engages theinferior spinous process1102. In a particular embodiment, when the multi-chamber expandableinterspinous process brace1000 is properly installed and inflated between the superiorspinous process1100 and theinferior spinous process1102, the superiorspinous process pocket1014 can engage and support the superiorspinous process1100. Further, the inferiorspinous process pocket1016 can engage and support aninferior spinous process1102.
• More specifically, the superior spinousprocess engagement structure1020 can extend slightly into and engage the superiorspinous process1100. Also, the inferior spinousprocess engagement structure1022 can extend slightly into and engage theinferior spinous process1102. Accordingly, the spinousprocess engagement structures1020,1022, the spinous process pockets1014,1016, or a combination thereof can substantially prevent the multi-chamber expandableinterspinous process brace1000 from migrating with respect to thespinous processes1100,1102.
• Also, in a particular embodiment, the multi-chamber expandableinterspinous process brace1000 can be movable between a deflated configuration, shown inFIG. 10, and one or more inflated configurations, shown inFIG. 11 andFIG. 12. In the deflated configuration, adistance1112 between the superiorspinous process pocket1014 and the inferiorspinous process pocket1016 can be at a minimum. However, as one or more materials are injected into thechambers1002,1004,1006 thedistance1112 between the superiorspinous process pocket1014 and the inferiorspinous process pocket1016 can increase.
• Accordingly, the multi-chamber expandableinterspinous process brace1000 can be installed between a superiorspinous process1100 and aninferior spinous process1102. Further, the multi-chamber expandableinterspinous process brace1000 can be expanded, e.g., by injecting one or more materials into thechambers1002,1004,1006 in order to increase the distance between the superiorspinous process1100 and theinferior spinous process1102.
• Alternatively, a distractor can be used to increase the distance between the superiorspinous process1100 and theinferior spinous process1102 and the multi-chamber expandableinterspinous process brace1000 can be expanded to support the superiorspinous process1100 and theinferior spinous process1102. After the multi-chamber expandableinterspinous process brace1000 is expanded accordingly, the distractor can be removed and the multi-chamber expandableinterspinous process brace1000 can support the superiorspinous process1100 and theinferior spinous process1102 to substantially prevent the distance between the superiorspinous process1102 and theinferior spinous process1100 from returning to a pre-distraction value.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace1000 can be injected with one or more injectable biocompatible materials that remain elastic after curing. Further, the injectable biocompatible materials can include polymer materials that remain elastic after curing. Also, the injectable biocompatible materials can include ceramics.
• For example, the polymer materials can include polyurethanes, polyolefins, silicones, silicone polyurethane copolymers, polymethylmethacrylate (PMMA), epoxies, cyanoacrylates, hydrogels, or a combination thereof. Further, the polyolefin materials can include polypropylenes, polyethylenes, halogenated polyolefins, or flouropolyolefins.
• The hydrogels can include polyacrylamide (PAAM), poly-N-isopropylacrylamine (PNIPAM), polyvinyl methylether (PVM), polyvinyl alcohol (PVA), polyethyl hydroxyethyl cellulose, poly(2-ethyl)oxazoline, polyethyleneoxide (PEO), polyethylglycol (PEG), polyacrylacid (PAA), polyacrylonitrile (PAN), polyvinylacrylate (PVA), polyvinylpyrrolidone (PVP), or a combination thereof.
• In a particular embodiment, the ceramics can include calcium phosphate, hydroxyapatite, calcium sulfate, bioactive glass, or a combination thereof. In an alternative embodiment, the injectable biocompatible materials can include one or more fluids such as sterile water, saline, or sterile air.
• In a particular embodiment, the hardness of the material used to inflate thecentral chamber1002 can be less than or equal to the hardness of the material used to inflate thesuperior chamber1004 and theinferior chamber1006, i.e., after the materials used to inflate thecentral chamber1002, thesuperior chamber1004, and theinferior chamber1006 are cured. Alternatively, the viscosity of the material used to inflate thecentral chamber1002 can be less than or equal to the viscosity of the material used to inflate thesuperior chamber1004 and theinferior chamber1006. In a particular embodiment, certain or all of the injected materials can be cured or cross-linked in situ to form a solid interspinous process brace with non-uniform bulk properties.
• FIG. 12 indicates that atether1200 can be installed around the multi-chamber expandableinterspinous process brace1000, after the multi-chamber expandableinterspinous process brace1000 is expanded as described herein. As shown, thetether1200 can include aproximal end1202 and adistal end1204. In a particular embodiment, thetether1200 can circumscribe the multi-chamber expandableinterspinous process brace1000 and thespinous processes1100,1102. Further, theends1202,1204 of thetether1200 can be brought together and one or more fasteners can be installed therethrough to connect theends1202,1204. Accordingly, thetether1200 can be installed in order to prevent the distance between thespinous processes1100,1102 from substantially increasing beyond the distance provided by the multi-chamber expandableinterspinous process brace1000 after it is expanded and to maintain engagement of the interspinous processes with the spinous process pockets1014,1016,engagement structures1020,1022, or a combination thereof.
• In a particular embodiment, thetether1200 can comprise a biocompatible elastomeric material that flexes during installation and provides a resistance fit against the inferior process. Further, thetether1200 can comprise a substantially non-resorbable suture or the like.
Description of a Fourth Embodiment of a Multi-Chamber Expandable Interspinous Process Brace
• Referring toFIG. 13 throughFIG. 15, a fourth embodiment of a multi-chamber expandable interspinous process brace is shown and is generally designated1300. As shown, the multi-chamber expandableinterspinous process brace1300 includes acentral chamber1302, a firstlateral chamber1304, and a secondlateral chamber1306.
• In a particular embodiment, thecentral chamber1302 can be generally vertically elongated. Also, in a particular embodiment, the firstlateral chamber1304 can be vertically elongated and can extend along a first side of thecentral chamber1302. The secondlateral chamber1306 can also be vertically elongated and can extend along a second side of thecentral chamber1302. As shown, thelateral chambers1304,1306 can extend beyond a top and bottom of thecentral chamber1302. Together, thecentral chamber1302, the firstlateral chamber1304, and the secondlateral chamber1306 can be provided in a shape that can generally engage and/or stabilize at least one spinous process, such as, for example, the spinous processes of two adjacent vertebrae. In a particular embodiment, together, thechambers1302,1304 and1306 can be generally H-shaped.
• Further, in a particular embodiment, thechambers1302,1304,1306 can be made from one or more expandable biocompatible materials. For example, the materials can be silicones, polyurethanes, polycarbonate urethanes, polyethylene terephthalate, silicone copolymers, polyolefins, or any combination thereof. Also, thechambers1302,1304,1306 can be non-porous or micro-porous, e.g., for venting purposes.
• As shown inFIG. 13, thecentral chamber1302 can include afirst injection tube1308. The firstlateral chamber1304 can include asecond injection tube1310 and the secondlateral chamber1306 can include athird injection tube1312. Theinjection tubes1308,1310,1312 can be used to provide one or more injectable biocompatible material to thechambers1302,1304,1306. In a particular embodiment, each of thecentral chamber1302, the firstlateral chamber1304, and the secondlateral chamber1306 of the multi-chamber expandableinterspinous process brace1300 can be expanded from a respective deflated configuration, shown inFIG. 13, to one of a plurality of inflated configurations, shown inFIG. 14 andFIG. 15, up to a maximum inflated configuration. Further, after thechambers1302,1304,1306 are inflated, or otherwise expanded, theinjection tubes1308,1310,1312 can be removed, as depicted inFIG. 15.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace1300 can include a first self-sealing valve (not shown) within thecentral chamber1302, e.g., adjacent to thefirst injection tube1308. Moreover, the multi-chamber expandableinterspinous process brace1300 can include a second self-sealing valve (not shown) within the firstlateral chamber1304, e.g., adjacent to thesecond injection tube1310. The multi-chamber expandableinterspinous process brace1300 can also include a third self-sealing valve (not shown) within the secondlateral chamber1306. The self-sealing valves can prevent thechambers1302,1304,1306 from leaking material after thechambers1302,1304,1306 are inflated and theinjection tubes1308,1310,1312 are removed.
• As illustrated inFIG. 13 throughFIG. 15, the multi-chamber expandableinterspinous process brace1300 can include a superiorspinous process pocket1314 that is formed by a top portion of thecentral chamber1302, a top portion of the firstlateral chamber1304, and a top portion of the secondlateral chamber1306. The multi-chamber expandableinterspinous process brace1300 can also include an inferiorspinous process pocket1316 that can be formed by a bottom portion of thecentral chamber1302, a bottom portion of the firstlateral chamber1304, and a bottom portion of the secondlateral chamber1306.
• Further, a superior spinousprocess engagement structure1320 can extend from thecentral chamber1304 within the superiorspinous process pocket1314. Also, an inferior spinousprocess engagement structure1322 can extend from thecentral chamber1304 within the inferiorspinous process pocket1316. In a particular embodiment, each of the spinousprocess engagement structures1320,1322 can be one or more spikes, one or more teeth, a combination thereof, or some other structure configured to engage a spinous process.
• FIG. 13 throughFIG. 15 indicate that the multi-chamber expandableinterspinous process brace1300 can be implanted between a superiorspinous process1400 and aninferior spinous process1402. In a particular embodiment, thechambers1302,1304,1306 can be inflated so the superiorspinous process pocket1314 can engage and support the superiorspinous process1400 and so the inferiorspinous process pocket1316 can engage and support aninferior spinous process1402.
• More specifically, the superior spinousprocess engagement structure1320 can extend slightly into and engage the superiorspinous process1400. Also, the inferior spinousprocess engagement structure1322 can extend slightly into and engage theinferior spinous process1402. Accordingly, the spinousprocess engagement structures1320,1322, the spinous process pockets1314,1316, or a combination thereof can substantially prevent the multi-chamber expandableinterspinous process brace1300 from migrating with respect to thespinous processes1400,1402.
• Also, in a particular embodiment, the multi-chamber expandableinterspinous process brace1300 can be movable between a deflated configuration, shown inFIG. 13, and one or more inflated configurations, shown inFIG. 14 andFIG. 15. In the deflated configuration, adistance1412 between the superiorspinous process pocket1314 and the inferiorspinous process pocket1316 can be at a minimum. However, as one or more materials are injected into thechambers1302,1304,1306 thedistance1412 between the superiorspinous process pocket1314 and the inferiorspinous process pocket1316 can increase.
• Accordingly, the multi-chamber expandableinterspinous process brace1300 can be installed between a superiorspinous process1400 and aninferior spinous process1402. Further, the multi-chamber expandableinterspinous process brace1300 can be expanded, e.g., by injecting one or more materials into thechambers1302,1304,1306 in order to increase the distance between the superiorspinous process1400 and theinferior spinous process1402.
• Alternatively, a distractor can be used to increase the distance between the superiorspinous process1400 and theinferior spinous process1402 and the multi-chamber expandableinterspinous process brace1300 can be expanded to support the superiorspinous process1400 and theinferior spinous process1402. After the multi-chamber expandableinterspinous process brace1300 is expanded accordingly, the distractor can be removed and the multi-chamber expandableinterspinous process brace1300 can support the superiorspinous process1400 and theinferior spinous process1402 to substantially prevent the distance between the superiorspinous process1402 and theinferior spinous process1400 from returning to a pre-distraction value.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace1300 can be injected with one or more injectable biocompatible materials that remain elastic after curing. Further, the injectable biocompatible materials can include polymer materials that remain elastic after curing. Also, the injectable biocompatible materials can include ceramics.
• For example, the polymer materials can include polyurethanes, polyolefins, silicones, silicone polyurethane copolymers, polymethylmethacrylate (PMMA), epoxies, cyanoacrylates, hydrogels, or a combination thereof. Further, the polyolefin materials can include polypropylenes, polyethylenes, halogenated polyolefins, or flouropolyolefins.
• The hydrogels can include polyacrylamide (PAAM), poly-N-isopropylacrylamine (PNIPAM), polyvinyl methylether (PVM), polyvinyl alcohol (PVA), polyethyl hydroxyethyl cellulose, poly(2-ethyl)oxazoline, polyethyleneoxide (PEO), polyethylglycol (PEG), polyacrylacid (PAA), polyacrylonitrile (PAN), polyvinylacrylate (PVA), polyvinylpyrrolidone (PVP), or a combination thereof.
• In a particular embodiment, the ceramics can include calcium phosphate, hydroxyapatite, calcium sulfate, bioactive glass, or a combination thereof. In an alternative embodiment, the injectable biocompatible materials can include one or more fluids such as sterile water, saline, or sterile air.
• In a particular embodiment, the hardness of the material used to inflate thecentral chamber1302 can be less than or equal to the hardness of the material used to inflate the firstlateral chamber1304 and the secondlateral chamber1306, i.e., after the materials used to inflate thecentral chamber1302, the firstlateral chamber1304, and the secondlateral chamber1306 are cured. Alternatively, the viscosity of the material used to inflate thecentral chamber1302 can be less than or equal to the viscosity of the material used to inflate the firstlateral chamber1304 and the secondlateral chamber1306. In a particular embodiment, certain or all of the injected materials can be cured or cross-linked in situ to form a solid interspinous process brace with non-uniform bulk properties.
• FIG. 15 indicates that atether1500 can be installed around the multi-chamber expandableinterspinous process brace1300, after the multi-chamber expandableinterspinous process brace1300 is expanded as described herein. As shown, thetether1500 can include aproximal end1502 and adistal end1504. In a particular embodiment, thetether1500 can circumscribe the multi-chamber expandableinterspinous process brace1300 and thespinous processes1400,1402. Further, theends1502,1504 of thetether1500 can be brought together and one or more fasteners can be installed therethrough to connect theends1502,1504. Accordingly, thetether1500 can be installed in order to prevent the distance between thespinous processes1400,1402 from substantially increasing beyond the distance provided by the multi-chamber expandableinterspinous process brace1300 after it is expanded and to maintain engagement of the interspinous processes with the spinous process pockets1314,1316,engagement structures1320,1322, or a combination thereof.
• In a particular embodiment, thetether1500 can comprise a biocompatible elastomeric material that flexes during installation and provides a resistance fit against the inferior process. Further, thetether1500 can comprise a substantially non-resorbable suture or the like.
Description of a Fifth Embodiment of a Multi-Chamber Expandable Interspinous Process Brace
• Referring toFIG. 16 throughFIG. 18, a fifth embodiment of a multi-chamber expandable interspinous process brace is shown and is generally designated1600. As shown, the multi-chamber expandableinterspinous process brace1600 includes acentral chamber1602, a firstlateral chamber1604, and a secondlateral chamber1606.
• In a particular embodiment, thecentral chamber1602 can be generally vertically elongated. Also, in a particular embodiment, the firstlateral chamber1604 can be vertically elongated and can extend along a first side of thecentral chamber1602. The secondlateral chamber1606 can also be vertically elongated and can extend along a second side of thecentral chamber1602. Together, thecentral chamber1602, the firstlateral chamber1604, and the secondlateral chamber1606 can be provided in a shape that can generally engage and/or stabilize at least one spinous process, such as, for example, the spinous processes of two adjacent vertebrae. In a particular embodiment, together, thechambers1602,1604 and1606 can be generally H-shaped.
• Further, in a particular embodiment, thechambers1602,1604,1606 can be made from one or more expandable biocompatible materials. For example, the materials can be silicones, polyurethanes, polycarbonate urethanes, polyethylene terephthalate, silicone copolymers, polyolefins, or any combination thereof. Also, thechambers1602,1604,1606 can be non-porous or micro-porous, e.g., for venting purposes.
• As shown inFIG. 16, thecentral chamber1602 can include afirst injection tube1608. The firstlateral chamber1604 can include asecond injection tube1610 and the secondlateral chamber1606 can include athird injection tube1612. Theinjection tubes1608,1610,1612 can be used to provide one or more injectable biocompatible material to thechambers1602,1604,1606. In a particular embodiment, each of thecentral chamber1602, the firstlateral chamber1604, and the secondlateral chamber1606 of the multi-chamber expandableinterspinous process brace1600 can be expanded from a respective deflated configuration, shown inFIG. 16, to one of a plurality of inflated configurations, shown inFIG. 17 andFIG. 18, up to a maximum inflated configuration. Further, after thechambers1602,1604,1606 are inflated, or otherwise expanded, theinjection tubes1608,1610,1612 can be removed, as depicted inFIG. 18.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace1600 can include a first self-sealing valve (not shown) within thecentral chamber1602, e.g., adjacent to thefirst injection tube1608. Moreover, the multi-chamber expandableinterspinous process brace1600 can include a second self-sealing valve (not shown) within the firstlateral chamber1604, e.g., adjacent to thesecond injection tube1610. The multi-chamber expandableinterspinous process brace1600 can also include a third self-sealing valve (not shown) within the secondlateral chamber1606. The self-sealing valves can prevent thechambers1602,1604,1606 from leaking material after thechambers1602,1604,1606 are inflated and theinjection tubes1608,1610,1612 are removed.
• As illustrated inFIG. 16 throughFIG. 18,central chamber1602 of the multi-chamber expandableinterspinous process brace1600 can include a superiorspinous process pocket1614. Thecentral chamber1602 of the multi-chamber expandableinterspinous process brace1600 can also include an inferiorspinous process pocket1616. Further, a superior spinousprocess engagement structure1620 can extend from thecentral chamber1604 within the superiorspinous process pocket1614. Also, an inferior spinousprocess engagement structure1622 can extend from thecentral chamber1604 within the inferiorspinous process pocket1616. In a particular embodiment, each of the spinousprocess engagement structures1620,1622 can be one or more spikes, one or more teeth, a combination thereof, or some other structure configured to engage a spinous process.
• FIG. 16 throughFIG. 18 indicate that the multi-chamber expandableinterspinous process brace1600 can be implanted between a superiorspinous process1700 and aninferior spinous process1702. In a particular embodiment, thechambers1602,1604,1606 can be inflated so the superiorspinous process pocket1614 can engage and support the superiorspinous process1700 and so the inferiorspinous process pocket1616 can engage and support aninferior spinous process1702.
• More specifically, the superior spinousprocess engagement structure1620 can extend slightly into and engage the superiorspinous process1700. Also, the inferior spinousprocess engagement structure1622 can extend slightly into and engage theinferior spinous process1702. Accordingly, the spinousprocess engagement structures1620,1622, the spinous process pockets1614,1616, or a combination thereof can substantially prevent the multi-chamber expandableinterspinous process brace1600 from migrating with respect to thespinous processes1700,1702.
• Also, in a particular embodiment, the multi-chamber expandableinterspinous process brace1600 can be movable between a deflated configuration, shown inFIG. 16, and one or more inflated configurations, shown inFIG. 17 andFIG. 18. In the deflated configuration, adistance1712 between the superiorspinous process pocket1614 and the inferiorspinous process pocket1616 can be at a minimum. However, as one or more materials are injected into thechambers1602,1604,1606 thedistance1712 between the superiorspinous process pocket1614 and the inferiorspinous process pocket1616 can increase.
• Accordingly, the multi-chamber expandableinterspinous process brace1600 can be installed between a superiorspinous process1700 and aninferior spinous process1702. Further, the multi-chamber expandableinterspinous process brace1600 can be expanded, e.g., by injecting one or more materials into thechambers1602,1604,1606 in order to increase the distance between the superiorspinous process1700 and theinferior spinous process1702.
• Alternatively, a distractor can be used to increase the distance between the superiorspinous process1700 and theinferior spinous process1702 and the multi-chamber expandableinterspinous process brace1600 can be expanded to support the superiorspinous process1700 and theinferior spinous process1702. After the multi-chamber expandableinterspinous process brace1600 is expanded accordingly, the distractor can be removed and the multi-chamber expandableinterspinous process brace1600 can support the superiorspinous process1700 and theinferior spinous process1702 to substantially prevent the distance between the superiorspinous process1702 and theinferior spinous process1700 from returning to a pre-distraction value.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace1600 can be injected with one or more injectable biocompatible materials that remain elastic after curing. Further, the injectable biocompatible materials can include polymer materials that remain elastic after curing. Also, the injectable biocompatible materials can include ceramics.
• For example, the polymer materials can include polyurethanes, polyolefins, silicones, silicone polyurethane copolymers, polymethylmethacrylate (PMMA), epoxies, cyanoacrylates, hydrogels, or a combination thereof. Further, the polyolefin materials can include polypropylenes, polyethylenes, halogenated polyolefins, or flouropolyolefins.
• The hydrogels can include polyacrylamide (PAAM), poly-N-isopropylacrylamine (PNIPAM), polyvinyl methylether (PVM), polyvinyl alcohol (PVA), polyethyl hydroxyethyl cellulose, poly(2-ethyl)oxazoline, polyethyleneoxide (PEO), polyethylglycol (PEG), polyacrylacid (PAA), polyacrylonitrile (PAN), polyvinylacrylate (PVA), polyvinylpyrrolidone (PVP), or a combination thereof.
• In a particular embodiment, the ceramics can include calcium phosphate, hydroxyapatite, calcium sulfate, bioactive glass, or a combination thereof. In an alternative embodiment, the injectable biocompatible materials can include one or more fluids such as sterile water, saline, or sterile air.
• In a particular embodiment, the hardness of the material used to inflate thecentral chamber1602 can be less than or equal to the hardness of the material used to inflate the firstlateral chamber1604 and the secondlateral chamber1606, i.e., after the materials used to inflate thecentral chamber1602, the firstlateral chamber1604, and the secondlateral chamber1606 are cured. Alternatively, the viscosity of the material used to inflate thecentral chamber1602 can be less than or equal to the viscosity of the material used to inflate the firstlateral chamber1604 and the secondlateral chamber1606. In a particular embodiment, certain or all of the injected materials can be cured or cross-linked in situ to form a solid interspinous process brace with non-uniform bulk properties.
• FIG. 18 indicates that atether1800 can be installed around the multi-chamber expandableinterspinous process brace1600, after the multi-chamber expandableinterspinous process brace1600 is expanded as described herein. As shown, thetether1800 can include aproximal end1802 and adistal end1804. In a particular embodiment, thetether1800 can circumscribe the multi-chamber expandableinterspinous process brace1600 and thespinous processes1700,1702. Further, theends1802,1804 of thetether1800 can be brought together and one or more fasteners can be installed therethrough to connect theends1802,1804. Accordingly, thetether1800 can be installed in order to prevent the distance between thespinous processes1700,1702 from substantially increasing beyond the distance provided by the multi-chamber expandableinterspinous process brace1600 after it is expanded and to maintain engagement of the interspinous processes with the spinous process pockets1614,1616,engagement structures1620,1622, or a combination thereof.
• In a particular embodiment, thetether1800 can comprise a biocompatible elastomeric material that flexes during installation and provides a resistance fit against the inferior process. Further, thetether1800 can comprise a substantially non-resorbable suture or the like.
Description of a Sixth Embodiment of a Multi-Chamber Expandable Interspinous Process Brace
• Referring toFIG. 19 throughFIG. 21, a sixth embodiment of a multi-chamber expandable interspinous process brace is shown and is generally designated1900. As shown, the multi-chamber expandableinterspinous process brace1900 includes anexterior chamber1902, a firstinterior chamber1904, and a secondinterior chamber1906.
• In a particular embodiment, theexterior chamber1902 can be provided in a shape that can generally engage and/or stabilize at least one spinous process, such as, for example, the spinous processes of two adjacent vertebrae. In a particular embodiment, theexterior chamber1902 can be generally H-shaped. Also, in a particular embodiment, the firstinterior chamber1904 can be vertically elongated and can be disposed within a first side of theexterior chamber1902. The secondinterior chamber1906 can also be vertically elongated and can be disposed within a second side of theexterior chamber1902.
• Further, in a particular embodiment, thechambers1902,1904,1906 can be made from one or more expandable biocompatible materials. For example, the materials can be silicones, polyurethanes, polycarbonate urethanes, polyethylene terephthalate, silicone copolymers, polyolefins, or any combination thereof. Also, thechambers1902,1904,1906 can be non-porous or micro-porous, e.g., for venting purposes.
• As shown inFIG. 19, theexterior chamber1902 can include afirst injection tube1908. The firstinterior chamber1904 can include asecond injection tube1910 and the secondinterior chamber1906 can include athird injection tube1912. Theinjection tubes1908,1910,1912 can be used to provide one or more injectable biocompatible material to thechambers1902,1904,1906. In a particular embodiment, each of theexterior chamber1902, the firstinterior chamber1904, and the secondinterior chamber1906 of the multi-chamber expandableinterspinous process brace1900 can be expanded from a respective deflated configuration, shown inFIG. 19, to one of a plurality of inflated configurations, shown inFIG. 20 andFIG. 21, up to a maximum inflated configuration. Further, after thechambers1902,1904,1906 are inflated, or otherwise expanded, theinjection tubes1908,1910,1912 can be removed, as depicted inFIG. 21.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace1900 can include a first self-sealing valve (not shown) within theexterior chamber1902, e.g., adjacent to thefirst injection tube1908. Moreover, the multi-chamber expandableinterspinous process brace1900 can include a second self-sealing valve (not shown) within the firstinterior chamber1904, e.g., adjacent to thesecond injection tube1910. The multi-chamber expandableinterspinous process brace1900 can also include a third self-sealing valve (not shown) within the secondinterior chamber1906. The self-sealing valves can prevent thechambers1902,1904,1906 from leaking material after thechambers1902,1904,1906 are inflated and theinjection tubes1908,1910,1912 are removed.
• As illustrated inFIG. 19 throughFIG. 21,exterior chamber1902 of the multi-chamber expandableinterspinous process brace1900 can include a superiorspinous process pocket1914. Theexterior chamber1902 of the multi-chamber expandableinterspinous process brace1900 can also include an inferiorspinous process pocket1916. Further, a superior spinousprocess engagement structure1922 can extend from theexterior chamber1902 within the superiorspinous process pocket1914. Also, an inferior spinousprocess engagement structure1920 can extend from theexterior chamber1902 within the inferiorspinous process pocket1916. In a particular embodiment, each of the spinousprocess engagement structures1920,1922 can be one or more spikes, one or more teeth, a combination thereof, or some other structure configured to engage a spinous process.
• FIG. 19 throughFIG. 21 indicate that the multi-chamber expandableinterspinous process brace1900 can be implanted between a superiorspinous process2000 and aninferior spinous process2002. In a particular embodiment, thechambers1902,1904,1906 can be inflated so the superiorspinous process pocket1914 can engage and support the superiorspinous process2000 and so the inferiorspinous process pocket1916 can engage and support aninferior spinous process2002.
• More specifically, the superior spinousprocess engagement structure1922 can extend slightly into and engage the superiorspinous process2000. Also, the inferior spinousprocess engagement structure1920 can extend slightly into and engage theinferior spinous process2002. Accordingly, the spinousprocess engagement structures1920,1922, the spinous process pockets1914,1916, or a combination thereof can substantially prevent the multi-chamber expandableinterspinous process brace1900 from migrating with respect to thespinous processes2000,2002.
• Also, in a particular embodiment, the multi-chamber expandableinterspinous process brace1900 can be movable between a deflated configuration, shown inFIG. 19, and one or more inflated configurations, shown inFIG. 20 andFIG. 21. In the deflated configuration, adistance2012 between the superiorspinous process pocket1914 and the inferiorspinous process pocket1916 can be at a minimum. However, as one or more materials are injected into thechambers1902,1904,1906 thedistance2012 between the superiorspinous process pocket1914 and the inferiorspinous process pocket1916 can increase.
• Accordingly, the multi-chamber expandableinterspinous process brace1900 can be installed between a superiorspinous process2000 and aninferior spinous process2002. Further, the multi-chamber expandableinterspinous process brace1900 can be expanded, e.g., by injecting one or more materials into thechambers1902,1904,1906 in order to increase the distance between the superiorspinous process2000 and theinferior spinous process2002.
• Alternatively, a distractor can be used to increase the distance between the superiorspinous process2000 and theinferior spinous process2002 and the multi-chamber expandableinterspinous process brace1900 can be expanded to support the superiorspinous process2000 and theinferior spinous process2002. After the multi-chamber expandableinterspinous process brace1900 is expanded accordingly, the distractor can be removed and the multi-chamber expandableinterspinous process brace1900 can support the superiorspinous process2000 and theinferior spinous process2002 to substantially prevent the distance between the superiorspinous process2002 and theinferior spinous process2000 from returning to a pre-distraction value.
• In a particular embodiment, the multi-chamber expandableinterspinous process brace1900 can be injected with one or more injectable biocompatible materials that remain elastic after curing. Further, the injectable biocompatible materials can include polymer materials that remain elastic after curing. Also, the injectable biocompatible materials can include ceramics.
• For example, the polymer materials can include polyurethanes, polyolefins, silicones, silicone polyurethane copolymers, polymethylmethacrylate (PMMA), epoxies, cyanoacrylates, hydrogels, or a combination thereof. Further, the polyolefin materials can include polypropylenes, polyethylenes, halogenated polyolefins, or flouropolyolefins.
• The hydrogels can include polyacrylamide (PAAM), poly-N-isopropylacrylamine (PNIPAM), polyvinyl methylether (PVM), polyvinyl alcohol (PVA), polyethyl hydroxyethyl cellulose, poly(2-ethyl)oxazoline, polyethyleneoxide (PEO), polyethylglycol (PEG), polyacrylacid (PAA), polyacrylonitrile (PAN), polyvinylacrylate (PVA), polyvinylpyrrolidone (PVP), or a combination thereof.
• In a particular embodiment, the ceramics can include calcium phosphate, hydroxyapatite, calcium sulfate, bioactive glass, or a combination thereof. In an alternative embodiment, the injectable biocompatible materials can include one or more fluids such as sterile water, saline, or sterile air.
• In a particular embodiment, the hardness of the material used to inflate theexterior chamber1902 can be less than or equal to the hardness of the material used to inflate the firstinterior chamber1904 and the secondinterior chamber1906, i.e., after the materials used to inflate theexterior chamber1902, the firstinterior chamber1904, and the secondinterior chamber1906 are cured. Alternatively, the viscosity of the material used to inflate theexterior chamber1902 can be less than or equal to the viscosity of the material used to inflate the firstinterior chamber1904 and the secondinterior chamber1906. In a particular embodiment, certain or all of the injected materials can be cured or cross-linked in situ to form a solid interspinous process brace with non-uniform bulk properties.
• FIG. 21 indicates that atether2100 can be installed around the multi-chamber expandableinterspinous process brace1900, after the multi-chamber expandableinterspinous process brace1900 is expanded as described herein. As shown, thetether2100 can include aproximal end2102 and adistal end2104. In a particular embodiment, thetether2100 can circumscribe the multi-chamber expandableinterspinous process brace1900 and thespinous processes2000,2002. Further, theends2102,2104 of thetether2100 can be brought together and one or more fasteners can be installed therethrough to connect theends2102,2104. Accordingly, thetether2100 can be installed in order to prevent the distance between thespinous processes2000,2002 from substantially increasing beyond the distance provided by the multi-chamber expandableinterspinous process brace1900 after it is expanded and to maintain engagement of the interspinous processes with the spinous process pockets1914,1916,engagement structures1920,1922, or a combination thereof.
• In a particular embodiment, thetether2100 can comprise a biocompatible elastomeric material that flexes during installation and provides a resistance fit against the inferior process. Further, thetether2100 can comprise a substantially non-resorbable suture or the like.
• Description of a Method of Treating a Spine
• Referring toFIG. 22, a method of treating a spine is shown and commences atblock2200. Atblock2200, a patient can be secured on an operating table. Depending on the surgical approach to be used, the patient can be secured in a prone position for a posterior approach, a supine position for an anterior approach, a lateral decubitus position for a lateral approach, or another position well known in the art. Atblock2202, the spine can be exposed in order to expose adjacent spinous processes. Further, atblock2204, a surgical retractor system can be installed to keep a surgical field open.
• Moving to block2206, a superior vertebra and inferior vertebra can be distracted. In a particular embodiment, the superior vertebra and inferior vertebra can be distracted using a distractor. Atblock2208, a distance between the adjacent spinous processes can be measured. Thereafter, atblock2210 it is determined whether the distraction is correct, e.g., has the superior vertebra and inferior vertebral been distracted such that a distance between the adjacent spinous processes has reached a value that a surgeon has deemed therapeutic. For example, the superior vertebra and inferior vertebra can be distracted in order to reduce impingement on a nerve root.
• If the distraction is not correct, the method can return to block2206 and the superior vertebra and inferior vertebra can be further distracted. Conversely, if the distraction is correct, the method can move to block2212 and a multi-chamber expandable interspinous process brace can be installed between a superior spinous process and an inferior spinous process. Thereafter, atblock2214, each chamber within the multi-chamber expandable interspinous process brace can be inflated.
• Moving to block2216, each chamber within the multi-chamber expandable interspinous process brace can be sealed. In a particular embodiment, each chamber within the multi-chamber expandable interspinous process brace can be sealed by curing the material within the each chamber of the multi-chamber expandable interspinous process brace. Alternatively, a plug, a dowel, or another similar device can be used to seal each chamber within the multi-chamber expandable interspinous process brace. Further, a one-way valve can be incorporated into each chamber of the multi-chamber expandable interspinous process brace and can allow material to be injected into each chamber of the multi-chamber expandable interspinous process brace, but prevent the same material from being expelled from each chamber of the multi-chamber expandable interspinous process brace.
• Atblock2218, each injection tube can be removed from the multi-chamber expandable interspinous process brace. Moreover, atblock2220, the material within one or more chambers of the multi-chamber expandable interspinous process brace can be cured. In a particular embodiment, the material within the multi-chamber expandable interspinous process brace can cure naturally, i.e., under ambient conditions, in situ. Alternatively, the material within one or more of the multi-chamber expandable interspinous process brace can be cured or crosslinked in situ using an energy source. For example, the energy source can be a light source that emits visible light, infrared (IR) light, or ultra-violet (UV) light. Further, the energy source can be a heating device, a radiation device, or other mechanical device. Alternatively or in addition, the material in one or more of the chambers can be crosslinked by introducing a chemical crosslinking agent into the chamber before removing the injection tube from the chamber.
• Proceeding to block2222, a tether can be installed around the multi-chamber expandable interspinous process brace. The tether can be installed in order to prevent a distance between the superior spinous process and the inferior spinous process from increasing substantially beyond the distance provided by the multi-chamber expandable interspinous process brace. Atblock2224, the surgical area can be irrigated. Atblock2226, the distractor can be removed. Also, atblock2228, the retractor system can be removed. Further, atblock2230, the surgical wound can be closed. The surgical wound can be closed by simply allowing the patient's skin to close due to the elasticity of the skin. Alternatively, the surgical wound can be closed using sutures, surgical staples, or any other suitable surgical technique well known in the art. Atblock2232, postoperative care can be initiated. The method can end atstate2232.
CONCLUSION
• With the configuration of structure described above, the multi-chamber expandable interspinous process brace provides a device that can be used to treat a spine and substantially alleviate or minimize one or more symptoms associated with disc degeneration, facet joint degeneration, or a combination thereof. For example, the multi-chamber expandable interspinous process brace can be installed between adjacent spinous processes in order to support the spinous processes and maintain them at or near a predetermined distance therebetween.
• As described above, the multi-chamber expandable interspinous process brace can include two or three chambers. Alternatively, the multi-chamber expandable interspinous process brace can include four chambers, five chambers, six chambers, seven chambers, eight chambers, nine chambers, ten chambers, etc. Also, the chambers can be separate chambers, as described above, or the chambers can be interconnected to allow material to flow therebetween. The chambers can be inflated sequentially or simultaneously.

Claims (13)

1. An expandable interspinous process spacer comprising:

an outer chamber formed of an expandable material, the outer chamber having a generally H-shape in both a relatively smaller deflated configuration and a relatively larger inflated configuration;

an inner expandable chamber disposed within and generally surrounded by the outer chamber;

the outer chamber being changeable from the relatively smaller deflated configuration to the relatively larger inflated configuration via injection of a first biocompatible material;

the inner chamber changeable from a relatively smaller deflated configuration to a relatively larger inflated configuration via injection of a second biocompatible material; the inner chamber changeable from the deflated configuration to the inflated configuration independently of the outer chamber.

2. The expandable spacer ofclaim 1 wherein the H-shape of the outer chamber forms first and second spinous process-receiving notches, oriented in generally opposite directions.

3. The expandable spacer ofclaim 1 further comprising the first biocompatible material disposed in the outer chamber and the second biocompatible material disposed in the inner chamber; wherein the first and second biocompatible materials are different.

4. The expandable spacer ofclaim 3 wherein the first biocompatible material is harder than the second biocompatible material.

5. The expandable spacer ofclaim 4 wherein the first biocompatible material in the outer chamber has a higher degree of cross-linking than the second biocompatible material in the inner chamber.

6. The expandable spacer ofclaim 3 wherein the first biocompatible material comprises at least one of a polymer and a ceramic.

7. The expandable spacer ofclaim 1 further comprising a first injection tube operatively connected to the outer chamber and a second injection tube operatively connected to the inner chamber.

8. The expandable spacer ofclaim 7 further comprising a self-sealing valve operatively disposed between the second injection tube and the inner chamber.

9. The expandable spacer ofclaim 1 further comprising a tether having a length sufficient to wrap around an exterior of the outer chamber when the outer chamber is in the inflated configuration.

10. The expandable spacer ofclaim 1 wherein the second biocompatible material comprises a fluid.

11. An interspinous process spacer comprising:

an outer chamber formed of an expandable material, the outer chamber having a generally H-shape in both a relatively smaller deflated configuration and a relatively larger inflated configuration;

a first biocompatible material disposed in the outer chamber, wherein injection of the first biocompatible material causes expansion of the outer chamber from the first relatively smaller deflated configuration to the second relatively larger inflated configuration;

an inner expandable chamber disposed within and generally surrounded by the outer chamber, the inner chamber having a generally H-shape in both a relatively smaller deflated configuration and a relatively larger inflated configuration;

a second biocompatible material disposed in the inner chamber; wherein injection of the second biocompatible material causes expansion of the inner chamber from the first relatively smaller deflated configuration to the second relatively larger inflated configuration;

wherein the inner chamber is changeable from the deflated configuration to the inflated configuration independently of the outer chamber;

wherein the first biocompatible material and the second biocompatible material have at least one different material property such that the first biocompatible material has greater hardness than the second biocompatible material.

12. The spacer ofclaim 11 wherein the first and second biocompatible materials are the same during injection, with the at least one different material property being degree of cross-linking after curing.

13. The spacer ofclaim 11 further comprising a first injection tube operatively connected to the outer chamber and a second injection tube operatively connected to the inner chamber.

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