Patent Publication Number: US-2022226024-A1

Title: Bony fusion system with porous material regions

Description:
TECHNICAL FIELD 
     Various embodiments described herein relate generally to stabilizing, promoting fusion between, and fusing mammalian bony segments, including systems and methods for stabilizing adjacent level mammalian bony segments. 
     BACKGROUND INFORMATION 
     It may be desirable to stabilize and fuse one or more adjacent level bony segments; the present invention provides such stabilization and fusion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a simplified posterior diagram of mammalian bony segment where the invention may be employed according to various embodiments. 
         FIG. 1B  is a simplified posterior diagram of mammalian bony segment with decorticated regions where the invention may be employed according to various embodiments. 
         FIG. 2A  is an isometric image of a mammalian bony segment adjacent level stabilization and fusion promoting system according to various embodiments. 
         FIG. 2B  is a front side image of a screw of a mammalian bony segment adjacent level stabilization system according to various embodiments. 
         FIG. 2C  is an enlarged image of section AA shown in  FIG. 2A  according to various embodiments. 
         FIG. 2D  is an enlarged image of section CC of section AA shown in  FIG. 2C  according to various embodiments. 
         FIG. 2E  is an enlarged image of another section CC of section AA shown in  FIG. 2C  according to various embodiments. 
         FIG. 2F  is an enlarged image of section BB shown in  FIG. 2A  according to various embodiments. 
         FIG. 3A  is a simplified diagram of mammalian bony segment adjacent level stabilization and fusion architecture shown in  FIG. 2A  coupled to a mammalian bony segment shown in  FIG. 1A  according to various embodiments. 
         FIG. 3B  is a simplified diagram of mammalian bony segment adjacent level stabilization and fusion architecture shown in  FIG. 2A  coupled to a mammalian bony segment with decorticated regions shown in  FIG. 1B  according to various embodiments. 
         FIG. 4A  is an isometric image of another mammalian bony segment adjacent level stabilization and fusion promoting system according to various embodiments. 
         FIG. 4B  is an isometric image of a rod with an empty bone graph compartment of a mammalian bony segment adjacent level stabilization system shown in  FIG. 3A  according to various embodiments. 
         FIG. 4C  is an isometric image of a rod with bone graph material embedded in its compartment of a mammalian bony segment adjacent level stabilization system shown in  FIG. 4B  according to various embodiments. 
         FIG. 5A  is a simplified diagram of mammalian bony segment adjacent level stabilization and fusion architecture shown in  FIG. 4A  coupled to a mammalian bony segment shown in  FIG. 1A  according to various embodiments. 
         FIG. 5B  is a simplified diagram of mammalian bony segment adjacent level stabilization and fusion architecture shown in  FIG. 4A  coupled to a mammalian bony segment with decorticated regions shown in  FIG. 1B  according to various embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Human structures such as adjacent bony elements (such as human vertebrae) separated by non-bony elements (such as disc nucleus) may become unstable due to injury or natural processes including aging. To help stabilize such human structures, one or more adjacent bony elements may be coupled together via a fusion promoting system. Apparatus may also be placed between one or more adjacent bony elements to help stabilize their relationship. In an embodiment, one or more adjacent bony elements may also desirably become fused over time to ensure stabilization of the related human structure including such elements. In an embodiment, a fusion promoting system used or employed to stabilize one or more adjacent bony elements may also become part of the fusion construct of the human structure. 
       FIG. 1A  is a simplified posterior diagram of a human structure including a mammalian bony segment  220 A where embodiments of the invention may be employed according to various embodiments. The bony segment  220 A includes adjacent bony structures  222 A-C. In an embodiment one or more bony regions or structures  222 A,  222 B,  222 C may be separated by one or more non-bony elements  240 A,  240 B,  240 C. In an embodiment, the bony regions  222 A,  222 B,  222 C may be vertebra separated by spinal discs  240 A,  240 B,  240 C in a cervical, thoracic, or lumbar region of a mammal including a human. In embodiment, each bony element  222 A-C may include a pedicle pair  232 A-C,  234 A-C, and a dorsal spinous process  236 A-C. 
       FIG. 1B  is a simplified posterior diagram of a mammalian bony segment  220 B with decorticated regions  238 A where embodiments of the invention may be employed according to various embodiments. Regions  238 A may be decorticated to aid in the possible fusion of adjacent bony elements  222 A-C. In an embodiment, a mammalian bony segment adjacent level stabilization and fusion promoting system  100 A-B (shown in  FIGS. 2A-3B ) may be employed in segments  220 A-B. 
       FIG. 2A  is an isometric image of a mammalian bony segment adjacent level stabilization and fusion promoting system  100 A that may be employed in the bony segments  220 A,  220 B as shown in  FIGS. 3A-B  according to various embodiments to couple bony elements  222 A-B via their pedicles  232 A-B. As shown in  FIG. 2A , a fusion promoting system  100 A may include several apparatus including bone engaging members  110 A that are coupled together via an engaging member coupling system  150 A,  150 B. The coupling system  150 A may securely and fixably couple a plurality of bone engaging members  110 A where the bone engaging members  110 A may be securely and fixably coupled to separate bony segments. The coupling system  150 A,  150 B may include a cross member  140 A,  140 B that is coupled to the bone engaging members  110 A via a lockable coupler  120 A,  120 B and a locking mechanism  130 A. The locking mechanism  130 A may hold the cross member  140 A,  140 B, bone engaging member  150 A,  150 B and lockable coupler  120 A,  120 B in a fixed relationship when engaged. 
     In an embodiment, the bone engaging members  110 A,  110 B,  110 C may be screws such as pedicle screws  110 A. The coupling system  150 A may fixably couple two or more screws via a cross member  140 A,  140 B that is coupled to the bone engaging members  110 A via a lockable coupler  120 A,  120 B and a locking mechanism  130 A. The locking mechanism  130 A may hold the cross member  140 A,  140 B, bone engaging member  150 A,  150 B and lockable coupler  120 A,  120 B in a fixed relationship when engaged. 
     In an embodiment, the coupling system  150 A,  150 B lockable coupler  120 A,  120 B include rod receiving heads  120 A,  120 B. The locking mechanism  130 A,  130 B may include set screws  130 A,  130 B. The cross member  140 A,  140 B may include rods  140 A,  140 B. In an embodiment, each rod receiving head  120 A,  120 B may engages screw  110 A,  110 B,  110 C such as via a polyaxial head  114 C. 
     In an embodiment, two pedicle screws  110 A,  110 B,  110 C each engaging a bony element may be coupled together via a coupling system  150 A,  150 B. The coupling system  150 A,  105 B may include rod receiving heads (lockable coupler)  120 A,  120 B, set screws (locking mechanism)  130 A,  130 B, and a rod (cross member)  140 A,  140 B. The rod receiving heads  120 A,  120 B may include set screws  130 A,  130 B than enable a rod  140 A,  140 B end  142 A to be secured to the head  120 A,  120 B and thus a pedicle screw  110 A,  110 B,  110 C. 
     In an embodiment, portions of the fusion promoting system  100 A apparatus may include porous regions such as shown in  FIGS. 2D-2F . In an embodiment, any of or all of the pedicle screws  110 A,  110 B,  110 C may include porous regions or osteo conductive regions as shown in  FIGS. 2A, 2B, 4A . In an embodiment, any of or all of the coupling system  150 A,  150 B may include porous regions or osteo conductive regions as shown in  FIG. 2A, 4A . In an embodiment, any of or all of the bone engaging members  110 A  110 B,  110 C, the lockable couplers  120 A,  120 B, the locking mechanisms  130 A,  130 B, and the cross members  140 A,  140 B may include porous regions or osteo conductive regions as shown in  FIG. 2A, 4A . 
     In an embodiment, a majority or all of the bone engaging member (pedicle screw&#39;s)  110 A shaft  112 A surface area may include porous regions or osteo conductive regions. In an embodiment, a majority or all of the cross members (rod&#39;s)  140 A surface area may include porous regions or osteo conductive regions. In an embodiment, a majority or all of the lockable coupler (rod receiving heads&#39;)  120 A surface area may include porous regions or osteo conductive regions other than the thread receiving area (that mate with locking mechanism (set screws)  130  threads). In an embodiment, a majority or all of the locking mechanism (set screws&#39;)  130 A surface area may include porous regions or osteo conductive regions other than its thread (that mate with lockable coupler (rod receiving heads&#39;)  102  thread receiving areas). 
     As shown in  FIG. 2B , a bone engaging member herein after pedicle screw  110 A,  110 C may include a shaft  112 A,  112 C and a polyaxial head  114 C. The shaft  112 A,  112 C may include a thread  116 C. In an embodiment, the pedicle screw  110 C shaft  112 C may include one or more fenestrations or slots  118 C creating an opening in the shaft  112 C. The fenestrations or slots  118 C may enable or promote bony fusion between a pedicle screw  110 C and bony elements  222 A-C where the pedicle screw  110 C may be employed as shown in  FIGS. 3A and 3B . In an embodiment, the inside of the fenestrations  118 C may include porous sections  119 C that may aid or promote bony fusion or conduction. 
     In an embodiment, the portions porous regions of a pedicle screw  110 A and coupling system  150 A,  150 B (including a lockable coupler hereinafter receiving head  120 A, a locking mechanism hereinafter set screw  130 A, and a cross member hereinafter rod  140 A) may be formed during production of the each.  FIG. 2C  is an enlarged image of section AA shown in  FIG. 2A  according to various embodiments. As shown in  FIGS. 2A and 2C  in an embodiment not all portions of the fusion promoting system  100 A may include porous regions. As shown in these figures, the set screw  130 A tool interface  132 A and threads or flange  134 A may not include porous regions. In another embodiment, all or a portions of the screw  110 A and the set screw  130 A tool interface  132 A and threads or flange  134 A may include porous regions. 
       FIG. 2D  is an enlarged image of an embodiment CC- 1  of a porous region area CC of section AA of the rod receiving head  120 A shown in  FIG. 2A  according to various embodiments. In an embodiment, the porous region CC- 1  may include a solid metal or alloy  152  covered with a porous 3-D metal surface  154 . In an embodiment, the metal  152  and porous metal surface  154  may be titanium and all or a portion may be formed via 3-D printing. 
       FIG. 2E  is an enlarged image of another embodiment CC- 2  of section CC of section AA shown in  FIG. 4A  according to various embodiments. Porous region CC- 2  may be a surface  156  of a material that is formed by etching the material. In an embodiment, sections or the entire surface of screws  110 A may be covered by a bone conduction material such as hydroxyapatite.  FIG. 2F  is an enlarged image of section BB of pedicle screw  110 A shaft  112 A shown in  FIG. 2A  according to various embodiments showing the coating of the surface  158  with a bone conduction material. 
     The porous regions of fusion promoting system  100 A may have sizing and shaping similar to trabecular bone regions to aid the bone conduction and fusion of the regions to bony elements  222 A-C so the fusion promoting system  100 A provides stabilization during a fusion process and becomes part of the bony fusion in an embodiment. cancellous bone, is typically found at the ends of long bones and within the vertebral bodies. Trabecular bone regions may higher porosity with more space resembling a lattice-like structure than other bone regions such as cortical bone where individual trabeculae of humans may be about 500-200 μm thick. The spacing between walls may be about 150 to 300 μm and with wall thickness of about 50-100 μm for the porous regions in an embodiment. The fusion promoting system  100 A may aid in the fusion process by creating more regions that enable bony fusion. 
       FIG. 4A  is an isometric image of another mammalian bony segment adjacent level stabilization and fusion promoting system  100 B that may be employed in the bony segments  220 A,  220 B as shown in  FIGS. 5A-B  according to various embodiments to couple two bony elements  222 A-B via their pedicles  232 A-B. As shown in  FIG. 4A , a fusion promoting system  100 B may include several pedicle screws  110 B coupled together via a coupling system  150 B including rod receiving heads  120 B, set screws  130 B, and a cavity rod  140 B. Fusion promoting system  100 B is similar to system  100 A except coupling system  150 B includes a rod  140 B with open space  142 B where material such as autogenous bone, bone matrix, or other osteo conductive material may be placed as shown in  FIG. 4C . The system  100 B cavity rod  140 B is shown in more detail in  FIGS. 4B and 4C  may include arms  144 B between ends  142 B that form a cavity  146 B (empty in  FIG. 4B  and filled with autogenous bone, bone matrix, or other osteo conductive material  148 B in  FIG. 4C ). In an embodiment, all or a portion of the rod  140 B may be covered with porous, bone fusion or osteo conductive enabling or promoting regions. The cavity  146 B may be filled with autogenous bone, bone matrix, or other osteo conductive material  148 B in an embodiment. 
     In an embodiment the systems  100 A,  100 B may be comprised of metal, metal polymer, ceramics, polymers, and combinations thereof. The polymers may include PEEK (Polyether ether ketone) in an embodiment. The accompanying drawings that form a part hereof show, by way of illustration and not of limitation, specific embodiments in which the subject matter may be practiced. The embodiments illustrated are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed herein. Other embodiments may be utilized and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. This Detailed Description, therefore, is not to be taken in a limiting sense, and the scope of various embodiments is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled. 
     Such embodiments of the inventive subject matter may be referred to herein individually or collectively by the term “invention” merely for convenience and without intending to voluntarily limit the scope of this application to any single invention or inventive concept, if more than one is in fact disclosed. Thus, although specific embodiments have been illustrated and described herein, any arrangement calculated to achieve the same purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the above description. 
     The Abstract of the Disclosure is provided to comply with 37 C.F.R. § 1.72(b), requiring an abstract that will allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In the foregoing Detailed Description, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted to require more features than are expressly recited in each claim. Rather, inventive subject matter may be found in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.