Abstract:
A PEEK spacer for use in the spine is disclosed. The PEEK spacer may be configured to fit through Kambin&#39;s Triangle and expand upon insertion.

Description:
PRIORITY 
     This application claims the benefit of U.S. Provisional Application Ser. No. 61/511,502, filed on Jul. 25, 2011, which is hereby incorporated by reference in its entirety herein. 
    
    
     FIELD 
     The present invention generally relates to a PEEK spacer for use in the spine. More particularly, the present invention relates to a PEEK spacer configured to fit through Kambin&#39;s Triangle and expand upon insertion. 
     SUMMARY 
     It is desirable to spare the facet joint when placing spacers for intervertebral stabilization, support and fusion. There is a need for a PEEK spacer that is small enough to fit through Kambin&#39;s Triangle, yet able to expand upon insertion to fully support and/or stabilize the intervertebral space. According to one embodiment of the present invention, the PEEK spacer may be placed via a facet sparing, transforaminal approach. In an embodiment, the PEEK spacer of the present invention may be placed through a minimally invasive operative access. In another embodiment, the PEEK spacer of the present invention may be placed through a percutaneous operative access. 
     According to one embodiment of the present invention, the PEEK spacer may be sized to be placed through a 15 mm×6 mm area at the L4-L5 vertebra. According to another aspect, the PEEK spacer of the present invention may be placed at any other desired vertebral level. In another embodiment of the present invention, the PEEK spacer may contain bone graft. According to one aspect, the PEEK spacer of the present invention may include an opening for bone graft insertion. In yet another embodiment of the present invention, the PEEK spacer may be configured to allow bony ingrowth through the spacer. According to one aspect of the present invention, the PEEK spacer may include an anti-backout feature. 
     In yet another embodiment, the PEEK spacer of the present invention may be configured to rotate from a first insertion position to a second implanted position. In an embodiment of the present invention, the PEEK spacer may be inserted in a first collapsed geometry and expanded to a second geometry after placement. In one embodiment of the present invention, the PEEK spacer may include arms, wings or other expandable members. In an embodiment of the present invention, expandable members may be solid such that fill material cannot escape back out of the entrance hole. In another embodiment expandable members may include slots or slits to allow bone ingrowth. 
     According to one embodiment of the present invention, the PEEK spacer may include a PEEK film configured to maintain the spacer in a collapsed geometry. In one aspect of the present invention, an expansion tool may be configured to pierce the PEEK film allowing the arms, wings or other expandable members to expand. 
     In yet another embodiment, the PEEK spacer of the present invention may be expanded using a screw or other suitable mechanism. According to another aspect of the present invention, the PEEK spacer may employ a ramp mechanism for expansion. 
     In an embodiment of the present invention, the PEEK spacer may include a central strut having a diversion configured to split a stream of bone or other fill material directing the fill material to both sides of the strut. 
     In yet another embodiment of the present invention, the arms, wings or other expandable members may be pivotally or otherwise movably attached to the spacer body. According to one aspect of the present invention, the PEEK spacer may include an asymmetrical taper along the implant width. In another embodiment, the PEEK spacer of the present invention may include lateral support features to help the implant stay upright when the disc space is subjected to shear forces. 
     According to one embodiment, a mesh container may be used with the PEEK spacer to contain fill material. 
     The detailed technology and preferred embodiments implemented for the subject invention are described in the following paragraphs accompanying the appended drawings for people skilled in this field to well appreciate the features of the claimed invention. It is understood that the features mentioned hereinbefore and those to be commented on hereinafter may be used not only in the specified combinations, but also in other combinations or in isolation, without departing from the scope of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts a perspective view of an embodiment of the present invention. 
         FIG. 2  depicts a perspective view of an embodiment of the present invention. 
         FIG. 3  depicts a perspective view of an embodiment of the present invention in an expanded configuration. 
         FIG. 4  depicts a side perspective view of an embodiment of the present invention in an expanded configuration. 
         FIG. 5  depicts a perspective view of an embodiment of the present invention. 
         FIG. 6  depicts a perspective view of an embodiment of the present invention. 
         FIG. 7  depicts a perspective view of an embodiment of the present invention. 
         FIG. 8  depicts a perspective view of an embodiment of the present invention. 
         FIG. 9  depicts a perspective view of an embodiment of the present invention. 
         FIG. 10  depicts a perspective view of an embodiment of the present invention. 
         FIG. 11  depicts a perspective view of an embodiment of the present invention. 
         FIG. 12  depicts a perspective view of an embodiment of the present invention. 
         FIG. 13  depicts a perspective view of an embodiment of the present invention. 
         FIG. 14  depicts a perspective view of an embodiment of the present invention. 
         FIG. 15  depicts a perspective view of an embodiment of the present invention. 
         FIG. 16  depicts a perspective view of an embodiment of the present invention. 
         FIG. 17  depicts a perspective view of an embodiment of the present invention. 
     
    
    
     While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular example embodiments described. On the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims. For illustrative purposes, cross-hatching, dashing or shading in the figures is provided to demonstrate sealed portions and/or integrated regions or devices for the package. 
     DETAILED DESCRIPTION 
     In the following descriptions, the present invention will be explained with reference to example embodiments thereof. However, these embodiments are not intended to limit the present invention to any specific example, embodiment, environment, applications or particular implementations described in these embodiments. Therefore, description of these embodiments is only for purpose of illustration rather than to limit the present invention. It should be appreciated that, in the following embodiments and the attached drawings, elements unrelated to the present invention are omitted from depiction; and dimensional relationships among individual elements in the attached drawings are illustrated only for ease of understanding, but not to limit the actual scale. 
     As shown in  FIGS. 1-5 , an embodiment of the present invention may include spacer body  12  and expandable members  14   a  and  14   b . According to an embodiment of the present invention, the spacer of the present invention may be inserted into an intervertebral disc space while sparing the facet joint. The spacer of the present invention is sized to fit through Kambin&#39;s triangle via a far lateral surgical approach thus sparing the facet joint. 
     Expandable members  14   a  and  14   b  may be movably attached to spacer body  12 . Peek or other suitable film  16  may be wrapped around spacer  10  such that spacer  10  remains in a collapsed geometry during insertion. In another embodiment, any thin thread, woven tape or other suitable material may be wrapped around spacer  10  such that spacer  10  remains in a collapsed geometry during insertion. 
     After placement of spacer  10  is complete, expansion tool  18  may be inserted through channels  20   a  and  20   b  such that tool  18  pierces film  16  allowing spacer  10  to be expanded into its expanded configuration. In an embodiment, film  16  may be pulled to expand spacer  10 . Spacer  10  may be rotated once placed. Bone graft or other desired bone substitute or fill material, may be inserted through an opening in spacer  10 . 
       FIG. 6  depicts another embodiment of spacer  30  having spacer body  32  and expandable member  34 . Opening  36  may accept the introduction of fill material. 
       FIG. 7  depicts an alternate embodiment of spacer  40  having spacer body  42  and expandable members  44   a  and  44   b.    
       FIG. 8  depicts another embodiment of spacer  50  having spacer body  52  and expandable members  54   a  and  54   b.    
       FIG. 9  depicts an embodiment of spacer  60  having spacer body  62  and expandable members  64   a  and  64   b.    
       FIG. 10  depicts an embodiment of spacer  70  having spacer body  72 , wherein only one expandable member  74   a  is shown to illustrate ramp  76 . 
       FIG. 11  depicts spacer  80  having spacer body  82  and expandable members  84   a  and  84   b . Spacer  80  is shown in the expanded position illustrating expansion tool  86 . 
       FIG. 12  depicts an alternate embodiment of spacer  90  having spacer body  92  and expandable members  94   a  and  94   b . Opening  96  may accept the introduction of fill material. 
       FIG. 13  depicts another embodiment of spacer  100  having spacer body  102  and an expandable member  104 . Opening  106  may accept the introduction of fill material. 
       FIG. 14  depicts an alternate embodiment of spacer  110  having expandable members  112 ,  114 ,  116 , and  118 . Expandable members  112 ,  114 ,  116 , and  118  are movably connected to one another such that spacer  110  may be inserted in a collapsed geometry and opened to an expanded geometry after placement. 
       FIG. 15  depicts spacer  120  having spacer body  122  and expandable members  124   a  and  124   b . Spacer  120  may be opened to an expanded configuration by drawing back distal ramp  128  back with a screw or other suitable mechanism. 
       FIG. 16  depicts an embodiment of spacer  130  having spacer body  132  and expandable member  134 . 
       FIG. 17  depicts an embodiment of spacer  140  having spacer body  142  and expandable members  144   a  and  144   b . Any of the embodiments of the present invention may include expandable members which may be expanded from a first closed position to a second open position, or any position therebetween, in a variety of ways. According to one aspect of the present invention, expandable members may be expanded by a mechanical expansion tool such as for example, a paddle or rod. In such an example embodiment, a mechanical expansion tool may be inserted through an opening in spacer body  142  and in between expandable members  144   a  and  144   b . A mechanical expansion tool may then be actuated to move expandable members from a first closed position to a second open position. Expandable members  144   a  and  144   b  may be partially opened, fully opened or opened to any position therebetween. 
     In another embodiment, expandable members may be expanded by the introduction of a balloon. In such an example embodiment, a deflated balloon may be inserted through an opening in spacer body  142  and in between expandable members  144   a  and  144   b . The balloon may then be inflated, moving expandable members  144   a  and  144   b  from a first closed position to a second open position. Expandable members  144   a  and  144   b  may be partially opened, fully opened or opened to any position therebetween. 
     In yet another embodiment, expandable members may be expanded by the introduction of fill material, such as for example bone graft, bone substitute or any biocompatible fill material or any combination thereof. Expandable members may be partially opened, fully opened or any opened to any position therebetween. 
     Although the description of the invention generally contemplates placing the PEEK spacer of the present invention in the intervertebral space, the PEEK spacer of the present invention may also be placed within a vertebral body. 
     Although the description of the invention generally contemplates using spacer comprised of PEEK, any biocompatible material or combination thereof may be used in the composition of the spacer. 
     The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is, therefore, desired that the present embodiment be considered in all respects as illustrative and not restrictive. Those skilled in the art may recognize other equivalents to the specific embodiment described herein which equivalents are intended to be encompassed by the claims attached hereto.