INTERSPINOUS PROCESS IMPLANT INCLUDING A BINDER AND METHOD OF IMPLANTATION
Systems in accordance with embodiments of the present invention can include an implant comprising a spacer for defining a minimum space between adjacent spinous processes, a distraction guide for piercing and distracting an interspinous ligament during implantation, and a binder for limiting or preventing flexion motion of the targeted motion segment. The binder can be secured to a brace associated with the implant during implantation by a capture device. In one embodiment, the capture device includes a fixed piece extending from the brace and a slidable piece associated with the fixed piece. A fastener can be rotated to pinch the binder between the slidable piece and a wall of the brace, securing the binder. A physician need not know the length of the binder prior to implantation, reducing the time required to perform a procedure.
This application is a continuation of U.S. patent application Ser. No. 11/095,680, entitled “Interspinous Process Implant Including a Binder and Method of Implantation,” filed Mar. 31, 2005, which claims priority to U.S. Provisional Patent Application No. 60/612,465, entitled “Interspinous Process Implant Including a Binder and Method of Implantation,” filed Sep. 23, 2004; each of which is incorporated herein by reference in its entirety.
This U.S. Patent Application incorporates by reference all of the following co-pending applications and issued patents:
U.S. patent application Ser. No. 10/850,267 (now Publication No. 2005-0010293), entitled “Distractible Interspinous Process Implant and Method of Implantation,” filed May 20, 2004;
U.S. Pat. No. 6,419,676, entitled “Spine Distraction Implant and Method,” issued Jul. 16, 2002 to Zucherman, et al.;
U.S. Pat. No. 6,451,019, entitled “Supplemental Spine Fixation Device and Method,” issued Sep. 17, 2002 to Zucherman, et al.;
U.S. Pat. No. 6,582,433, entitled “Spine Fixation Device and Method,” issued Jun. 24, 2003 to Yun;
U.S. Pat. No. 6,652,527, entitled “Supplemental Spine Fixation Device and Method, issued Nov. 25, 2003 to Zucherman, et al.;
U.S. Pat. No. 6,695,842, entitled “Interspinous Process Distraction System and Method with Positionable Wing and Method,” issued Feb. 24, 2004 to Zucherman, et al.;
U.S. Pat. No. 6,699,246, entitled “Spine Distraction Implant,” issued Mar. 2, 2004 to Zucherman, et al.; and
U.S. Pat. No. 6,712,819, entitled “Mating Insertion Instruments for Spinal Implants and Methods of Use,” issued Mar. 30, 2004 to Zuchennan, et al.
BACKGROUNDThis invention relates to interspinous process implants. As the present society ages, it is anticipated that there will be an increase in adverse spinal conditions which are characteristic of older people. Certain biochemical changes can occur with aging, affecting tissue found throughout the body. In the spine, the structure of the intervertebral disks can be compromised, in part as the structure of the annulus fibrosus of the intervertebral disk weakens due to degenerative effects. Spondylosis (also referred to as spinal osteoarthritis) is one example of a degenerative disorder that can cause loss of normal spinal structure and function. The degenerative process can impact the cervical, thoracic, and/or lumbar regions of the spine, affecting the intervertebral disks and the facet joints. Pain associated with degenerative disorders is often triggered by one or both of forward flexion and hyperextension. Spondylosis in the thoracic region of the spine can cause disk pain during flexion and facet pain during hyperextension. Spondylosis can affect the lumbar region of the spine, which carries most of the body's weight, and movement can stimulate pain fibers in the annulus fibrosus and facet joints.
Over time, loss of disk height can result in a degenerative cascade with deterioration of all components of the motion segment resulting in segment instability and ultimately in spinal stenosis (including, but not limited to, central canal and lateral stenosis). Spinal stenosis results in a reduction in foraminal area (i.e., the available space for the passage of nerves and blood vessels) which compresses the nerve roots and causes radicular pain. Another symptom of spinal stenosis is myelopathy. Extension and ipsilateral rotation further reduces the foraminal area and contributes to pain, nerve root compression and neural injury. During the process of deterioration, disks can become herniated and/or become internally torn and chronically painful. When symptoms seem to emanate from both anterior (disk) and posterior (facets and foramen) structures, patients cannot tolerate positions of extension or flexion.
A common procedure for handling pain associated with degenerative spinal disk disease is the use of devices for fusing together two or more adjacent vertebral bodies. The procedure is known by a number of terms, one of which is interbody fusion. Interbody fusion can be accomplished through the use of a number of devices and methods known in the art. These include screw arrangements, solid bone implant methodologies, and fusion devices which include a cage or other mechanism which is packed with bone and/or bone growth inducing substances. All of the above are implanted between adjacent vertebral bodies in order to fuse the vertebral bodies together, alleviating associated pain.
Depending on the degree of slip and other factors, a physician may fuse the vertebra “as is,” or fuse the vertebrae and also use a supplemental device. Supplemental devices are often associated with primary fusion devices and methods, and assist in the fusion process. Supplemental devices assist during the several month period when bone from the adjacent vertebral bodies is growing together through the primary fusion device in order to fuse the adjacent vertebral bodies. During this period it is advantageous to have the vertebral bodies held immobile with respect to each other so that sufficient bone growth can be established. Supplemental devices can include hook and rod arrangements, screw arrangements, and a number of other devices which include straps, wires, and bands, all of which are used to immobilize one portion of the spine relative to another. Supplemental devices have the disadvantage that they generally require extensive surgical procedures in addition to the extensive procedure surrounding the primary fusion implant. Such extensive surgical procedures include additional risks, including risk of causing damage to the spinal nerves during implantation. Spinal fusion can include highly invasive surgery requiring use of a general anesthetic, which itself includes additional risks. Risks further include the possibility of infection, and extensive trauma and damage to the bone of the vertebrae caused either by anchoring of the primary fusion device or the supplemental device. Finally, spinal fusion can result in an absolute loss of relative movement between vertebral bodies.
U.S. Pat. No. 5,496,318 to Howland, et al. teaches supplemental devices for the stabilization of the spine for use with surgical procedures to implant a primary fusion device. Howland '318 teaches an H-shaped spacer having two pieces held together by a belt, steel cable, or polytetrafluoroethane web material, one or both ends of which includes an attachment device fixedly connected with the respective end. Howland '318 teaches that the vertebra are preferably surgically modified to include a square notch to locate the fixation device in a preferred location. Howland '318 has the further disadvantage that the belt, cable or web material must be sized before implantation, increasing the procedure time to include sizing time and reducing the precision of the fit where both ends of the belt, cable or web material include attachment devices (and as such are incrementally sized).
U.S. Pat. No. 5,609,634 to Voydeville teaches a prosthesis including a semi-flexible interspinous block positioned between adjacent spinous processes and a ligament made from the same material. A physician must lace the ligament through the interspinous block and around the spinous processes in a figure of eight, through the interspinous block and around the spinous processes in an oval, and suture the ligament to itself to fix the interspinous block in place. Voydeville has the disadvantage of requiring significant displacement and/or removal of tissue associated with the spinous processes, potentially resulting in significant trauma and damage. Voydeville has the further disadvantage of requiring the physician to lace the interspinous ligament through the interspinous block. Such a procedure can require care and time, particularly because a physician's ability to view the area of interest is complicated by suffusion of blood in the area of interest.
It would be advantageous if a device and procedure for limiting flexion and extension of adjacent vertebral bodies were as simple and easy to perform as possible, and would preferably (though not necessarily) leave intact all bone, ligament, and other tissue which comprise and surround the spine. Accordingly, there is a need for procedures and implants which are minimally invasive and which can supplement or substitute for primary fusion devices and methods, or other spine fixation devices and methods. Accordingly, a need exists to develop spine implants that alleviate pain caused by spinal stenosis and other such conditions caused by damage to, or degeneration of, the spine. Such implants would distract (increase) or maintain the space between the vertebrae to increase the foraminal area and reduce pressure on the nerves and blood vessels of the spine, and limit or block flexion to reduce pain resulting from spondylosis and other such degenerative conditions.
A further need exists for development of a minimally invasive surgical implantation method for spine implants that preserves the physiology of the spine. A still further need exists for an implant that accommodates the distinct anatomical structures of the spine, minimizes further trauma to the spine, and obviates the need for invasive methods of surgical implantation. Additionally, a need exists to address adverse spinal conditions that are exacerbated by spinal extension and flexion.
BRIEF DESCRIPTION OF THE DRAWINGSFurther details of embodiments of the present invention are explained with the help of the attached drawings in which:
The distraction guide 106 includes a tip from which the distraction guide 106 expands, the tip having a diameter sufficiently small such that the tip can pierce an opening in an interspinous ligament and/or can be inserted into a small initial dilated opening. The diameter and/or cross-sectional area of the distraction guide 106 then gradually increases until it is substantially similar to the diameter of the main body 101 and spacer 102. The tapered front end eases the ability of a physician to urge the implant 100 between adjacent spinous processes. When urging the main body 101 between adjacent spinous processes, the front end of the distraction guide 106 distracts the adjacent spinous processes and dilates the interspinous ligament so that a space between the adjacent spinous processes is approximately the diameter of the spacer 102.
The shape of the spacer 102 is such that for purposes of insertion between the spinous processes, the spinous processes need not be altered or cut away in order to accommodate the spacer 102. Additionally, associated ligaments need not be cut away and there is little or no damage to the adjacent or surrounding tissues. As shown in
The first wing 108 has a lower portion 113 and an upper portion 112. As shown in
The implant 100 further includes an adjustable wing 150 (also referred to herein as a second wing). The adjustable wing 150 has a lower portion 152 and an upper portion 153. Similar to the first wing 108, the adjustable wing 150 is designed to accommodate the anatomical form or contour of the spinous processes and/or lamina. The adjustable wing 150 is secured to the main body 101 with a fastener 154. The adjustable wing 150 also has an alignment tab 158. When the adjustable wing 150 is initially placed on the main body 101, the alignment tab 158 engages the alignment track 103. The alignment tab 158 slides within the alignment track 103 and helps to maintain the adjustable wing 150 substantially parallel with the first wing 108. When the main body 101 is inserted into the patient and the adjustable wing 150 has been attached, the adjustable wing 150 also can prevent side-to-side, or posterior-to-anterior movement.
Referring to
In some circumstances, for example where a patient develops spondylosis or other degenerative disorder that makes both flexion and extension painful and uncomfortable, it can be desired that the spinous processes be further immobilized, while providing the same ease of implantation as provided with implants described above. Referring to
As can be seen in
The brace 308 can include a height along the spine greater than a height of the spacer 302 so that movement along a longitudinal axis L in the direction of insertion is limited or blocked by the brace 308 when the brace 308 contacts the lateral surfaces of the spinous processes. In this way, the brace 308 can function similarly to the wing 108 of the above described implant 100. In other embodiments, the brace 308 can have a height greater or smaller than as shown. Once the binder 330 is positioned around the spinous processes and secured, movement of the implant 300 relative to the spinous processes is limited by the binder 330 along the longitudinal axis as well as along the spinous processes (i.e., anterior-to-posterior movement).
A free end of the binder 330 can be secured to the brace 308 by a capture device 320 associated with the brace 308. The brace 308 can include a flange 310 from which the capture device 320 can extend. In the embodiment shown in
The binder 330 can comprise a strap, ribbon, tether, cord, or some other flexible (or semi-flexible), and preferably threadable structure. The binder 330 can be made from a biocompatible material. In an embodiment, the binder 330 can be made from a braided polyester suture material. Braided polyester suture materials include, for example, Ethibond, Ethiflex, Mersilene, and Dacron, and are nonabsorbable, having high tensile strength, low tissue reactivity and improved handling. In other embodiments, the binder 330 can be made from stainless steel (i.e., surgical steel), which can be braided into a tether or woven into a strap, for example. In still other embodiments, the binder 330 can be made from some other material (or combination of materials) having similar properties.
The distraction guide 306 can optionally include a slot, bore, cut-out or other cavity 309 formed in the distraction guide 306 through which the binder 330 can be threaded or positioned. Such a cavity can allow on-axis positioning of the binder 330 (i.e., the binder can be substantially aligned with the longitudinal axis L of the implant 300). Further, capturing the binder 330 within a slot or bore can prevent or limit shifting of the distraction guide 306 relative to the binder 330 to further secure the implant 300 between the spinous processes.
As will be readily apparent to one of skill in the art, implants in accordance with the present invention provide significant benefits to a physician by simplifying an implantation procedure and reducing procedure time, while providing an implant that can limit or block flexion and extension of the spine. A physician can position an implant between adjacent spinous processes and can position a binder 330 connected with the brace 308 around the spinous processes without requiring the physician to measure an appropriate length of the binder 330 prior to implantation. The capture device 320 allows the binder 330 to be secured to the brace 308 anywhere along a portion of the binder 330, the portion being between a distal end 334 of the binder 330 and the proximal end 332. The physician can secure the binder 330 to the brace 308 to achieve the desired range of movement (if any) of the spinous processes during flexion.
The capture device 320 and brace 308 can have alternative designs to that shown in
Referring to
Embodiments of implants have been described in
Implants in accordance with the present invention can enable a physician to limit or block flexion and extension in a targeted motion segment while minifying invasiveness of an implantation procedure (relative to implantation procedures of the prior art). However, such implants can also be used where more extensive implantation procedures are desired. For example, as shown in
Still another embodiment of an implant 700 in accordance with the present invention is shown in the end view of
Use of a binder to limit or prevent flexion can provide an additional benefit of limiting movement along the longitudinal axis L (shown in
Referring to
In other embodiments, implants in accordance with the present invention can include a second wing (or an upper portion and/or lower portion) extendable from the distraction guide. In this way an implant and a device for limiting or blocking movement along a longitudinal axis of the implant can be included in a single piece, possibly simplifying implantation. Referring to
In an alternative embodiment, implants 1100 in accordance with the present invention can include spring-loaded upper and/or lower portions 653,652 such as shown in
In still further embodiments, implants in accordance with the present invention can optionally employ some other additional mechanism for limiting or blocking motion along the longitudinal axis of the implant. Mechanisms shown and described in
As can be seen in
The distraction guide 806 of the implant 1300 can be wedge-shaped, as described above, or approximately conical, as shown in
The capture device 820 is shown in cross-section in
The slidable piece 827 can optionally further include a guide 912 extending from the slidable piece 827 so that the guide 912 overlaps a portion of the brace 908. The guide 912 can extend, for example, a distance roughly similar to the maximum distance between the capture surface 898 and the brace wall 914, and can help ensure that the binder 330 is captured between the capture surface 898 and the brace wall 914. In other embodiments, the capture device 820 of
A method of surgically implanting an implant 1300 in accordance with an embodiment as described above in
In some embodiments, the implant can be fabricated from medical grade metals such as titanium, stainless steel, cobalt chrome, and alloys thereof, or other suitable implant material having similar high strength and biocompatible properties. Additionally, the implant can be at least partially fabricated from a shape memory metal, for example Nitinol, which is a combination of titanium and nickel. Such materials are typically radiopaque, and appear during x-ray imaging, and other types of imaging. Implants in accordance with the present invention, and/or portions thereof can also be fabricated from somewhat flexible and/or deflectable material. In these embodiments, the implant and/or portions thereof can be fabricated in whole or in part from medical grade biocompatible polymers, copolymers, blends, and composites of polymers. A copolymer is a polymer derived from more than one species of monomer. A polymer composite is a heterogeneous combination of two or more materials, wherein the constituents are not miscible, and therefore exhibit an interface between one another. A polymer blend is a macroscopically homogeneous mixture of two or more different species of polymer. Many polymers, copolymers, blends, and composites of polymers are radiolucent and do not appear during x-ray or other types of imaging. Implants comprising such materials can provide a physician with a less obstructed view of the spine under imaging, than with an implant comprising radiopaque materials entirely. However, the implant need not comprise any radiolucent materials.
One group of biocompatible polymers is the polyaryletherketone group which has several members including polyetheretherketone (PEEK), and polyetherketoneketone (PEKK). PEEK is proven as a durable material for implants, and meets the criterion of biocompatibility. Medical grade PEEK is available from Victrex Corporation of Lancashire, Great Britain under the product name PEEK-OPTIMA. Medical grade PEKK is available from Oxford Performance Materials under the name OXPEKK, and also from CoorsTek under the name BioPEKK. These medical grade materials are also available as reinforced polymer resins, such reinforced resins displaying even greater material strength. In an embodiment, the implant can be fabricated from PEEK 450 G, which is an unfilled PEEK approved for medical implantation available from Victrex. Other sources of this material include Gharda located in Panoli, India. PEEK 450 G has the following approximate properties:
PEEK 450 G has appropriate physical and mechanical properties and is suitable for carrying and spreading a physical load between the adjacent spinous processes. The implant and/or portions thereof can be formed by extrusion, injection, compression molding and/or machining techniques.
It should be noted that the material selected can also be filled. Fillers can be added to a polymer, copolymer, polymer blend, or polymer composite to reinforce a polymeric material. Fillers are added to modify properties such as mechanical, optical, and thermal properties. For example, carbon fibers can be added to reinforce polymers mechanically to enhance strength for certain uses, such as for load bearing devices. In some embodiments, other grades of PEEK are available and contemplated for use in implants in accordance with the present invention, such as 30% glass-filled or 30% carbon-filled grades, provided such materials are cleared for use in implantable devices by the FDA, or other regulatory body. Glass-filled PEEK reduces the expansion rate and increases the flexural modulus of PEEK relative to unfilled PEEK. The resulting product is known to be ideal for improved strength, stiffness, or stability. Carbon-filled PEEK is known to have enhanced compressive strength and stiffness, and a lower expansion rate relative to unfilled PEEK. Carbon-filled PEEK also offers wear resistance and load carrying capability.
As will be appreciated, other suitable similarly biocompatible thermoplastic or thermoplastic polycondensate materials that resist fatigue, have good memory, are flexible, and/or deflectable, have very low moisture absorption, and good wear and/or abrasion resistance, can be used without departing from the scope of the invention. As mentioned, the implant can be comprised of polyetherketoneketone (PEKK). Other material that can be used include polyetherketone (PEK), polyetherketoneetherketoneketone (PEKEKK), polyetheretherketoneketone (PEEKK), and generally a polyaryletheretherketone. Further, other polyketones can be used as well as other thermoplastics. Reference to appropriate polymers that can be used in the implant can be made to the following documents, all of which are incorporated herein by reference. These documents include: PCT Publication WO 02/02158 A1, dated Jan. 10, 2002, entitled “Bio-Compatible Polymeric Materials;” PCT Publication WO 02/00275 A1, dated Jan. 3, 2002, entitled “Bio-Compatible Polymeric Materials;” and, PCT Publication WO 02/00270 A1, dated Jan. 3, 2002, entitled “Bio-Compatible Polymeric Materials.” Other materials such as Bionate®, polycarbonate urethane, available from the Polymer Technology Group, Berkeley, Calif., may also be appropriate because of the good oxidative stability, biocompatibility, mechanical strength and abrasion resistance. Other thermoplastic materials and other high molecular weight polymers can be used.
As described above, the binder can be made from a biocompatible material. In an embodiment, the binder can be made from a braided polyester suture material. Braided polyester suture materials include, for example, Ethibond, Ethiflex, Mersilene, and Dacron, and are nonabsorbable, having high tensile strength, low tissue reactivity and improved handling. In other embodiments, the binder can be made from stainless steel (i.e., surgical steel), which can be braided into a tether or woven into a strap, for example. In still other embodiments, the binder can be made from some other material (or combination of materials) having similar properties.
The foregoing description of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations will be apparent to practitioners skilled in this art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.
Claims
1. A method, comprising:
- disposing an elongated member substantially around a pair of adjacent spinous processes; and
- rotating a distal end portion of a tool to couple a first end portion of the elongated member to a second end portion of the elongated member after the disposing.
2. The method of claim 1, further comprising:
- adjusting, before the rotating, a length of the elongated member substantially around the pair of adjacent spinous processes such that an amount of flexion associated with the pair of adjacent spinous processes is limited.
3. The method of claim 1, further comprising:
- adjusting, before the rotating, a tension of the elongated member substantially around the pair of adjacent spinous processes such that an amount of flexion associated with the pair of adjacent spinous processes is limited.
4. The method of claim 1, wherein the tool is a first tool, the method further comprising:
- inserting, before the disposing, the elongated member into a patient's body via a second tool.
5. The method of claim 1, wherein the disposing include threading the elongated member between interspinous ligaments of the pair of adjacent spinous processes so that the pair of adjacent spinous processes are disposed within a loop defined by the elongated member.
6. The method of claim 1, wherein the rotating includes rotating a capture device such that the second end portion of the elongated member is coupled to a brace, the first end portion of the elongated member is fixedly coupled to the brace.
7. The method of claim 1, further comprising:
- forming, before the inserting, an incision in the patient's body; and
- inserting, before the disposing, the elongated member into the patient's body through the incision.
8. The method of claim 1, further comprising:
- forming, before the inserting, an incision in the patient's body;
- inserting, before the disposing, the elongated member into the patient's body through the incision; and
- inserting, before the rotating, a distal end portion of the tool into the patient's body through the incision such that a proximal end portion of the tool is disposed outside of the patient's body.
9. The method of claim 1, wherein the tool is a first tool, further comprising:
- forming, before the inserting, the incision in the patient's body;
- inserting, before the disposing, the elongated member into the patient's body through the incision via a second tool; and
- inserting, before the actuating, a distal end portion of the first tool into the patient's body through the incision such that a proximal end portion of the first tool is disposed outside of the patient's body.
10. A method, comprising:
- inserting an elongated member into a patient's body through an incision in the body;
- disposing, after the inserting, the elongated member substantially around a pair of adjacent spinous processes; and
- actuating, after the disposing, a tool through the incision to couple a first end portion of the elongated member to a second end portion of the elongated member.
11. The method of claim 10, further comprising:
- adjusting, before the actuating, a length of the elongated member substantially around the pair of adjacent spinous processes such that an amount of flexion associated with the pair of adjacent spinous processes is limited.
12. The method of claim 10, further comprising:
- adjusting, before the actuating, a tension of the elongated member substantially around the pair of adjacent spinous processes such that an amount of flexion associated with the pair of adjacent spinous processes is limited.
13. The method of claim 10, wherein the disposing include threading the elongated member between interspinous ligaments of the pair of adjacent spinous processes so that the pair of adjacent spinous processes are disposed within a loop defined by the elongated member.
14. The method of claim 10, wherein the actuating includes rotating a distal end portion of the tool such that a capture device couples the second end portion of the elongated member to a brace, the first end portion of the elongated member is fixedly coupled to the brace.
15. The method of claim 10, further comprising:
- forming, before the inserting, the incision in the patient's body; and
- inserting, before the disposing, the elongated member into the patient's body through the incision.
16. The method of claim 10, further comprising:
- forming, before the inserting, the incision in the patient's body;
- inserting, before the disposing, the elongated member into the patient's body through the incision; and
- inserting, before the actuating, a distal end portion of the tool into the patient's body through the incision such that a proximal end portion of the tool is disposed outside of the patient's body.
17. A kit, comprising:
- a coupler;
- an elongated member, a first end portion of the elongated member being fixedly coupled to the coupler; and
- a tool configured to couple a second end portion of the elongated member to the coupler while the elongated member is disposed substantially around a pair of adjacent spinous processes.
18. The kit of claim 17, wherein:
- the coupler includes a brace and a capture device;
- the first end portion of the elongated member fixedly coupled to the brace, the second end portion of the elongated member removably coupleable to the brace via the capture device; and
- the tool configured to rotate the capture device while the elongated member is disposed around the pair of adjacent spinous processes.
19. The kit of claim 17, wherein the tool is a first tool, the kit further comprising:
- a second tool configured to insert the coupler and the elongated member into a patient's body through an incision.
20. The kit of claim 17, wherein the tool is a first tool, the kit further comprising:
- a second tool configured to insert the coupler and the elongated member into a patient's body through an incision,
- a distal end portion of the first tool is configured to be inserted into the patient's body through the incision and couple the second end portion of the elongated member to the coupler.
21. A method, comprising:
- placing an elongated member around a pair of adjacent spinous processes in a patient's body, the elongated member having a distal end and a proximal end; and
- coupling a distal portion of the elongated member to a proximal portion of the elongated member, via a tool, such that a displacement of the two adjacent spinous processes away from each other is limited.
22. The method of claim 21, further comprising:
- adjusting a coupling member, the coupling member engaging the distal portion and the proximal portion of the elongated member, such that the displacement of the two adjacent spinous processes away from each other is further limited.
23. The method of claim 21, further comprising:
- adjusting a coupling member via tool, the coupling member moveably engaged with the distal portion and the proximal portion of the elongated member, such that a displacement of the two adjacent spinous processes away from each other after the adjusting is greater than the displacement of the two adjacent spinous processes before the adjusting.
24. The method of claim 21, further comprising:
- positioning a spacer between the pair of adjacent spinous processes.
25. The method of claim 21, further comprising:
- positioning, before the coupling, a spacer between the pair of adjacent spinous processes, the spacer being coupled to the elongated member.
Type: Application
Filed: Oct 25, 2007
Publication Date: Feb 21, 2008
Inventors: James Zucherman (San Francisco, CA), Ken Hsu (San Francisco, CA), Henry Klyce (Piedmont, CA), Charles Winslow (Walnut Creek, CA), Scott Yerby (Montara, CA), John Flynn (Concord, CA), Steven Mitchell (Pleasant Hill, CA), John Markwart (Castro Valley, CA)
Application Number: 11/923,814
International Classification: A61F 2/44 (20060101); A61B 17/58 (20060101);