US20120323276A1 - Expandable interspinous device - Google Patents

Abstract

Disclosed is a device that is configured to be implanted adjacent interspinous processes of a patient. In one aspect, a spinal implant device comprises: a spacer region adapted to be positioned between first and second spinous processes of first and second vertebral bodies to limit movement of the first spinous process and the second spinous process toward one another; and an attachment region attached to the spacer region, the attachment region adapted to attach to the first spinous process via a fastener, the attachment region comprising a pair of pads having attachment elements that are configured to attach onto the spinous process

Description

REFERENCE TO PRIORITY DOCUMENTS
• This application claims priority of co-pending U.S. Provisional Patent Application Ser. No. 61/515,541 entitled EXPANDABLE INTERSPINOUS DEVICE and filed on Aug. 5, 2011, and co-pending U.S. Provisional Patent Application Ser. No. 61/498,354 entitled EXPANDABLE INTERSPINOUS DEVICE and filed on Jun. 17, 2011. The disclosures of the Provisional Patent Applications are hereby incorporated by reference in their entirety.
BACKGROUND
• Many people suffers from back pain due to any of a variety of factors. Such back pain can sometime be treated by introducing interspinous implants between the spinous processes of adjacent vertebral bodies in a patient's spine. This can maintain the stability of the vertebral column to increase the size of the spinal canal and allow the patient to have normal mobility.
• There currently is need for improved device that can be implanted between spinous processes.
SUMMARY
• Disclosed is a device that is configured to be implanted adjacent interspinous processes of a patient. In one aspect, a spinal implant device comprises: a spacer region adapted to be positioned between first and second spinous processes of first and second vertebral bodies to limit movement of the first spinous process and the second spinous process toward one another; and an attachment region attached to the spacer region, the attachment region adapted to attach to the first spinous process via a fastener, the attachment region comprising a pair of pads having attachment elements that are configured to attach onto the spinous process.
• Other features and advantages should be apparent from the following description of various embodiments, which illustrate, by way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 shows a perspective view of a device that is configured for placement between the spinous processes of two adjacent vertebral bodies.
• FIG. 2 shows an enlarged, perspective view of the device ofFIG. 1
• FIG. 3 shows a side view of the device ofFIG. 1.
• FIG. 4 shows the device positioned between a pair of spinous processes.
• FIGS. 5-6 show another embodiment of an interspinous device.
• FIGS. 6-10A show another embodiment of an interspinous device.
• FIGS. 10B-11 show another embodiment of an interspinous device.
• FIG. 12 shows another embodiment of an interspinous device.
• FIG. 13 shows another embodiment of an interspinous device.
DETAILED DESCRIPTION
• Before the present subject matter is further described, it is to be understood that this subject matter described herein is not limited to particular embodiments described, as such may of course vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting. Unless defined otherwise, all technical terms used herein have the same meaning as commonly understood by one skilled in the art to which this subject matter belongs.
• As will be apparent to those of skill in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope of the subject matter described herein. Any recited method can be carried out in the order of events recited or in any other order which is logically possible.
• FIG. 1 shows a perspective view of adevice105 that is configured for placement between the spinous processes SP1 and SP2 of two adjacent vertebral bodies.FIG. 2 shows an enlarged, perspective view of thedevice105 andFIG. 3 shows a side view of thedevice105. Thedevice105 includes a spacer orcentral region205 that is sized and shaped to fit between the spinous processes of the two adjacent vertebral bodies. Thedevice105 further includes a pair ofprotrusions210 that extend outward from the central region. The protrusions are size and shaped to couple to the spinous processes, as described more fully below.
• With reference toFIGS. 2 and 3, thecentral region205 comprises a cylindrical body having one or more openings that extend through the walls of the body. In the illustrated embodiment, thecentral region205 is cylindrical and substantially circular when viewed from the side (as shown inFIG. 3). Acentral shaft305 extends through thecentral region205. Along an upper portion of thecentral region205, anelongated gap208 is formed, which is sized and shaped to receive alocking member215, as described below. It should be appreciated that thecentral region205 can have other shapes.
• With reference still toFIGS. 2 and 3, theprotrusions210 comprise outwardly extending bodies or tabs. A pair of such protrusions extends outwardly from thecentral region205 on each side of thegap208. A space between each of the protrusions is sized and shaped to receive at least a portion of a spinous process. For example, as shown inFIG. 1, theprotrusions210aand210bdefine a space therebetween that is sized and shaped to receive the spinous process SP1. In this manner, thedevice105 can be positioned between the spinous processes SP1 and SP2 with theprotrusions210 coupling to respective spinous processes to thereby serve anchoring or stabilizing functions.
• As shown inFIGS. 2 and 3, thelocking member215 is sized and shaped to fit within theelongated gap215. In this regard, as shown inFIG. 3, theelongated gap215 forms a pair of slots that are sized and shaped to receive complementary-shaped tabs on thelocking member215. This permits thelocking member215 to be slidably positioned into thegap215 by properly aligning the locking member adjacent thegap215 and then sliding the locking member into the gap along a vector that would be normal to the plane ofFIG. 3. After the locking member is positioned in thegap215, locking member may be rotated to cause a cam portion of the locking member to outwardly separate the central region along opposite sides of thegap215 and thereby lock the central region onto the spinous processes.
• This is described in more detail with reference toFIG. 4, which shows thecentral region205 of thedevice105 positioned between a pair of spinous processes SP1 and SP2. At this stage, thelocking member215 is not coupled to thecentral region205. Thelocking member215 can now be slid into the central region and rotated to cause the cam to expand the central region such that it exerts a force onto the spinous processes and fixes thereto. Note that a series of slots220 (FIG. 2) are located along the wall of thecentral region205. The slots are sized and shaped to receive at least a portion of a spinous process when thedevice105 is implanted.
• FIG. 5 shows another embodiment of the ISP device, referred to asdevice505. Thedevice505 includes four members including afirst member510,second member515,third member520, andfourth member525. Each of the second, third, and fourth member has a central shaft or opening that is sized and shaped to receive anelongated shank530 such that the members may be coupled to one another by inserting theshank530 through the central openings of the other members. Thefourth member525 serves as a cap with internal threads that couple to external threads on theshank530. In this manner, thefourth member525 can be secured to theshank530 with the second andthird members515 and520 secured along theshank530 between thefourth member525 and an enlarged head535 of thefirst member510.
• With reference still toFIG. 5, thesecond member515 andthird member520 may be positioned with a space S therebetween. Each of the second member and third member are sized and shaped to be positioned adjacent or juxtaposed with a spinous process of a respective vertebra. The spinous process can be positioned within the space S and the second and third members tightened about the spinous process. The cap of the fourth member can then be tightened to secure the spinous process within the space S.
• FIG. 6 shows another embodiment of the ISP device, referred to asdevice605. Thedevice605 includes amain body610 that is sized and shaped to be positioned within the space between a pair of spinous processes. The main body may be coupled to an expander member615 that threadably inserts into anopening625 in themain body610.
• Themain body610 has a substantially tubular configuration with an internal shaft and an out wall that forms a substantially cylindrical shape. A plurality of openings extend through the outer wall and communicate with the internal shaft.
• The expander member615 is elongated in shape and has a threaded shank that fits into theopening625 of the main body. The expander member615 can be rotated to engage with threads inside theopening625 to engage the expander member615 with themain body610.
• Any of the device embodiments can be made of any biologically adaptable or compatible materials such as Polyether ether ketone (PEEK). Additional materials considered acceptable for biological implantation are well known and include, but are not limited to, stainless steel, titanium, tantalum, combination metallic alloys, various plastics, resins, ceramics, biologically absorbable materials and the like. In addition, any of the devices may be packed with a bone graft or other suitable material for fusing to adjacent bone.
• FIGS. 7 and 8 show another embodiment of adevice705 that is configured for placement between the spinous processes SP1 and SP2 of two adjacent vertebral bodies. Thedevice705 includes two pairs of arms including a first pair with first andsecond arms710aand710b,as well as a second pair with third andfourth arms710cand710d.Thearms710aand710bin the first pair of arms are sized and shaped to grasp or otherwise couple to the spinous process SP1. Likewise, thearms710cand710din the second pair of arms are sized and shaped to grasp or otherwise couple to the spinous process SP2. As described in detail below, the relative positions of the arms can be adjusted by rotatingactuator715.
• Rotation of theactuator715 causes the arms in a respective pair to rotate about an axis of rotation of theactuator715. That is, the arms rotate about the axis in a scissor-like manner. This permits the arms to be opened up to a size that would accept a respective spinous process and then closed to a size that grasps the respective spinous process. In an embodiment, each arm has a flat inner surface with projections that are configured to increase a frictional hold with the spinous process to which the arm is coupled, as shown inFIGS. 9 and 10.
• FIG. 9 shows a perspective view of thedevice705 in an assembled state andFIG. 10A shows thedevice705 in an exploded state. Thedevice705 includes afirst arm member905 that includes a pair of arms. Asecond arm member910 includes another pair of arms. Each arm member includes a central shaft in which acoupler member915 and a screw member920 may be co-axially positioned. The screw member920 couples to acap925 that is positioned on an opposite end of the screw member920 to secure thedevice705 in an assembled state. Thecoupler member915 and screw member rotatably attach to thearm members905 and910. When the screw member is rotated, it causes thearm members905 and910 to also rotate such that the arms may be rotated toward and away from another.
• FIGS. 10B and 11 show another embodiment of the ISP device, referred to asdevice1005. Thedevice505 includes a pair ofopposed members1010 that define a space S therebetween. Each of themembers1005 is sized and shaped to be positioned adjacent or juxtaposed with a spinous process of a respective vertebra. The spinous process can be positioned within the space S. In this regard, each of themembers1010 includes one ormore pads1017 having attachment elements, such as spikes, that are configured to attach onto the spinous process. The pads are attached to the members in a ball and socket manner such that the pads are configured to rotate and pivot about the ball and socket attachment.
• With reference still toFIGS. 10B and 11, aconnector1020 connects the twomembers1010 to one another. Theconnector1010 is an elongated shaft having a first end with ahead1025 that sits in a seat in one of themembers1010. A second end region of theconnector1010 extends through a hole in thesecond member1010. Theconnector1020 and hole may be threaded such that rotation of theconnector1010 causes the twomembers1010 to move toward or away from one another depending on the direction of rotation. In this manner, the spinous process may be secured between the twomembers1010. Anouter housing1030 is positioned around theconnector1020. The outer housing is sized and shaped to receive bone material for fusing with the spine.
• In another embodiment, shown inFIG. 12, the device includes a pair ofmembers1005 and aconnector1010 therebetween. The connector is formed of afirst connector member1205 and asecond connector member1210 that coupled to one another such as in a male-female relationship. The connector members include a ratchet interface that permits the two connector members to be pushed toward one another in an interlocking fashion. The ratchet interface permits the twomembers1005 to be successively moved toward one another and locked in successively closer positions so as to vary the size of the space S. The configuration of the ratchet can be varied to permit various increments of relative movement between the twomembers1005.
• In yet another embodiment, shown inFIG. 13, the device includes a pair ofmembers1005 that are monolithically coupled to one another via aconnector1305 that is monolithically attached to the two members. A set ofpads1317 are positioned on the members wherein thepads1317 include attachment elements such as spikes. Thepads1317 define a space therebetween that is sized to receive an interspinous process. The positions of at least some of the pads can be moveably adjusted to vary the size of the space S between facing pads.
• Although embodiments of various methods and devices are described herein in detail with reference to certain versions, it should be appreciated that other versions, embodiments, methods of use, and combinations thereof are also possible. Therefore the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein.

Claims (4)

1. A spinal implant device, comprising:

a spacer region adapted to be positioned between first and second spinous processes of first and second vertebral bodies to limit movement of the first spinous process and the second spinous process toward one another; and

an attachment region attached to the spacer region, the attachment region adapted to attach to the first spinous process via a fastener, the attachment region comprising a pair of pads having attachment elements that are configured to attach onto the spinous process.

2. A device as inclaim 1, wherein the attachment region attaches to an anterior segment of the spinous process.

3. A device as inclaim 1, wherein the attachment region attaches to a laminal segment of the spinous process.

4. A device as inclaim 1, wherein the attachment region attaches an anterior segment and a laminal segment of the spinous process.

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