Abstract:
Apparatus and methods for distracting or compressing distance between a first and second honey structure and for engaging a connecting element.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a continuation of co-pending U.S. patent application Ser. No. 11/604,134, entitled “Spinal Distractor, Compressor, and Rod Engaging System and Method,” filed Nov. 24, 2006, which claims the benefit of priority to U.S. Provisional Patent Application Ser. No. 60/739,268, filed Nov. 23, 2005. Priority of the aforementioned filing dates is hereby claimed and the entire disclosures of which are hereby incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    The invention relates generally to apparatus and methods for distracting or compressing the distance between a first and second boney structure. 
         [0003]    It is desirable to enable a user to distract or compress the distance between a first and second boney structure. The present invention provides such a system and method. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention includes apparatus and methods for controllably distracting or compressing the distance between a first and second boney structure via a connecting element. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    The features, objects, and advantages of the present invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings in which like reference characters identify correspondingly throughout and wherein: 
           [0006]      FIG. 1A  is an isometric diagram of a compressor and distracter apparatus coupled to a connecting element according to various embodiments; 
           [0007]      FIG. 1B  is a side, partial sectional diagram of a compressor and distracter apparatus coupled to a connecting element according to various embodiments; 
           [0008]      FIG. 1C  is a top diagram of a compressor and distracter apparatus coupled to a connecting element according to various embodiments; 
           [0009]      FIG. 1D  is a side, sectional diagram of a compressor and distracter apparatus coupled to a connecting element according to various embodiments; 
           [0010]      FIG. 1E  is an exploded diagram of a compressor and distracter apparatus and a connecting element according to various embodiments; 
           [0011]      FIG. 1F  is an exploded diagram of a section of a compressor and distracter apparatus according to various embodiments; 
           [0012]      FIG. 2A  is a diagram of a compressor and distracter apparatus coupled to a connecting element employed to compress or distract the disc space between two vertebra according to various embodiments; 
           [0013]      FIG. 2B  is a diagram of a connecting element and bony structure interface system for engaging the connecting element to a bony structure according to various embodiments; 
           [0014]      FIG. 2C  is a diagram of a compressor and distracter apparatus coupled to a connecting element and a bony structure interface system to distract the bony structure relative to another structure according to various embodiments; 
           [0015]      FIG. 2D  is a diagram of a compressor and distracter apparatus coupled to a connecting element and a bony structure interface system to compress the bony structure relative to another structure according to various embodiments; 
           [0016]      FIG. 2E  is a horizontal view of two connecting elements coupled to respective bony structure interface systems, the systems coupled to a bony structure according to various embodiments; and 
           [0017]      FIG. 2F  is a sagittal view of a connecting element coupled to a first and a second bony structure interface system, the first system coupled to a first bony structure and the second system coupled to the second bony structure according to various embodiments. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    Throughout this description, embodiments and variations are described for the purpose of illustrating uses and implementations of the invention. The illustrative description should be understood as presenting examples of the invention, rather than as limiting the scope of the invention. 
         [0019]      FIG. 1A  is an isometric diagram of a compressor and distracter apparatus  100  coupled to a connecting element  120  according to various embodiments. The apparatus  100  includes a ratchet body or base  104 , ratchet mechanism  117 , ratchet actuator handle  106 , ratchet direction selector  102 , slidable hook  105 , and hook slide recess and connecting element holder  126 . The hook slide  105  is coupled to the ratchet mechanism  117  where the slide  105  moves relative to the connecting element holder  126 . The slide  105  may move toward or away from the connecting element  126  as a function of the ratchet direction selection  102 . In operation, the connecting element  120  distal end  123  may be fixably coupled to a first bony structure ( 12  in  FIG. 2A ). The hook slide catch  125  may be physically coupled to a second bony structure ( 14  in  FIG. 2A ). As the ratchet mechanism  117  is operated by handle  106  the second bony structure  14  may be compressed toward or distracted away the first bony structure  12 . Due the ratchet mechanism  117 , the compression or distraction is controllably performed in discrete increments based on the direction  102  and handle actuations  106 . 
         [0020]    The connecting element holder  126  may have a curvature radius, R 1 . The connecting element  120  may a curvature radius, R 2 . In embodiment R 1  may be similar to R 2  to enable smooth compression or distraction between two bony structures  12 ,  14 . Further, movement between the bony structures  12 ,  14  may follow a curvature radius, R 3  where R 1  and R 2  are similar to R 3 . In spinal applications R 3  may be approximately equal to the lordosis between a first vertebra  12  and a second vertebra  14 .  FIG. 1B  is a side, partial sectional diagram of the compressor and distracter apparatus  100  coupled to a connecting element  120  according to various embodiments. The apparatus  100  includes a master pin  109  and main ratchet gear  101 . The master pin  109  is couples the direction selector  102  to the ratchet mechanism  117 . The main ratchet gear  101  have a fixed number of gears having a fixed tooth shape and size. The gear  101  is coupled to reciprocal teeth in the hook slide ( 124  in  FIGS. 1D and 1E ). Accordingly, when the ratchet mechanism  117  is actuated (via handle  106 ), the hook slide  105  is moved a fixed, predetermined distance, permitting an apparatus  100  user to controllably distract or compress the space or distance between two bony structures  12 ,  14 . 
         [0021]      FIG. 1C  is a top diagram of a compressor and distracter apparatus  100  coupled to a connecting element  120  according to various embodiments. The apparatus  100  may include a connecting element connector  121 . The connecting element connector  121  may include a compressible collet that may be inserted into a connecting element  120  recess ( 122  in  FIG. 1E ). In an embodiment after the collet  121  is inserted into the connecting element  120  recess  122 , a locking pin ( 109  in  FIG. 1E ) may be inserted into the collet  121  via the locking pin  109  actuator  128  ( FIG. 1C ). The locking pin  109  insertion may fixably expand the collet  121  within the connecting element  120  recess  122  and prevent separation of the connecting element  120  from the holder  126 . In an embodiment the connecting element  120  is a cylindrical rod that is substantially incompressible along its longitudinal axis. The connecting element  120  may be any element  120  may span between two bony structures and a substantially incompressible longitudinal axis. The connecting element  120  may include a dynamic connector where the dynamic connector may be made substantially incompressible along its longitudinal axis during insertion or implantation. 
         [0022]      FIG. 1D  is a side, sectional diagram of the compressor and distracter apparatus  100  coupled to a connecting element  120  according to various embodiments. As shown in  FIG. 1D  the connecting element holder  126  includes a sleeve for the hook slide  105 . The hook slide  105  includes a plurality of teeth  124  at is proximal end. The teeth  124  are configured to mate with the ratchet mechanism  117  main ratchet gears  101 . When the ratchet mechanism  117  is actuated via the handle  106  the hook slide  105  is translated with the connecting element holder  126  so the hook slide  105  catch  125  is moved relative to the fixed connecting element coupler (collet in an embodiment)  121 . In an embodiment a first bony structure is fixably coupled to connecting element  120  distal end  123 . A second bony structure may be fixably coupled to another apparatus that is releasably couplable to the hook slide  105  catch  125 . The apparatus  100  may then be actuated to translate the hook slide  105  relative the coupled connecting element  120 . Accordingly the second bony structure  14  may be compressed toward or distracted away from the first bony structure  12 . In an embodiment the first and the second bony structure may be single anatomical bony structure that has been separated such as long bone fracture. 
         [0023]      FIG. 1E  is an exploded diagram of the compressor and distracter apparatus  100  and a connecting element  120  according to various embodiments.  FIG. 1F  is an exploded diagram of a section of the ratchet mechanism  117  of the compressor and distracter apparatus  100  according to various embodiments. The apparatus  100  may include a ratchet housing/handle  104 , director selector  102 , main ratchet gear  101 , pin advancer  103 , hook slide  105 , ratchet actuator  106 , hook slide cover  107 , lee spring  108 , master pin  109 , ball spring plunger  110 , screw  111 , lee spring  112 , ratchet lock pin  113 , ratchet lock pin  114 , block pin advancer  115 , pin advancer  116 , ratchet mechanism  117 , screws  118 , connecting element locking pin  119 , connecting element coupler (collet)  121 , hook slide gear  124 , hook slide recess/connecting element holder  126 , slide path  127 , and locking pin control  128 . As can be shown in  FIGS. 1E and 1F  the apparatus  100  enables a user to incrementally translate the hook slide  105  relative to the hook slide recess/connecting element holder  126 . 
         [0024]      FIG. 2A  is a diagram of a compressor and distracter apparatus  100  coupled to a connecting element  120  employed to compress or distract the disc space  13  between two vertebra  12 ,  14  of a spine  10  according to various embodiments. The spine  10  may include a plurality of vertebra  12 ,  14  covered by skin  16 . The connecting element  120  may be fixably coupled to the first vertebra  12  via a bone connecting element ( 30  in  FIG. 2B ). The hook slide  105  may be coupled to the second vertebra  14  via a bone connecting element  30  and connecting cannula  22 B. A connecting cannula  22 A may be coupled to first vertebra  12  via the bone connecting element. Depending on the direction selection  102 , actuation of handle  106  may distract the second vertebra  14  away from the first vertebra  12  ( FIG. 2C ) or may compress the second vertebra  14  toward the first vertebra  12  ( FIG. 2D ). 
         [0025]      FIG. 2B  is a diagram of a connecting element  120  and bony structure coupling system  200  for engaging the connecting element to a bony structure according to various embodiments. The bony structure coupling system  200  may include a bone screw  30  coupled to a connecting element  120  receiver  32  via a pin  38 , a connecting element engaging saddle  34  rotatably coupled to a receiver locking element  36 , a locking element driver  40 , and a cannula couplable to the receiver  32 . The locking element driver  40  may be releasably coupled to the receiver locking element  36 . The cannula  22  may include a cannula slot  24  that the hook slide catch  125  of the hook slide  105  may releasably engage. 
         [0026]      FIG. 2C  is a diagram of the compressor and distracter apparatus  100  coupled to a connecting element  120  and a bony structure coupling system  200  to distract a bony structure coupled to the system  200  relative to another bony structure fixably coupled to the connecting element  120  according to various embodiments. As shown in  FIG. 2C  as the hook slide is incrementally slide away from the connecting element  120  (force vector  130 ), the system  200  is also distracted away from the connecting element  120 .  FIG. 2D  is a diagram of the compressor and distracter apparatus  100  coupled to a connecting element  120  and a bony structure coupling system  200  to compress a bony structure coupled to the system  200  toward another bony structure fixably coupled to the connecting element  120  according to various embodiments. As shown in  FIG. 2D  as the hook slide is incrementally slide toward the connecting element  120  (force vectors  130 ), the system  200  is also compressed toward the connecting element  120 . 
         [0027]      FIG. 2E  is a horizontal view of two connecting elements coupled to respective bony structure system  200 , the systems coupled to a bony structure  14  according to various embodiments. In  FIG. 2E  a bone screw  30  in placed on a left and a right pedicle of a vertebra  14 . Bone dowels  42  may also be placed in a facet joints.  FIG. 2F  is a sagittal view of a connecting element  120  coupled to a first and a second bony structure coupling system  200 . The first system  200  may be coupled to a first bony structure  14  and the second system  200  may be coupled to the second bony structure  12  according to various embodiments. The compressor and distracter apparatus  100  may be used to distract or compress the disc space  13 . 
         [0028]    While this invention has been described in terms of a best mode for achieving the objectives of the invention, it will be appreciated by those skilled in the art that variations may be accomplished in view of these teachings without deviating from the spirit or scope of the present invention.