Patent Publication Number: US-2005131394-A1

Title: Clamping device

Description:
CROSS REFERENCE TO RELATED APPLICATION(S)  
      None.  
     BACKGROUND OF THE INVENTION  
      The present invention relates generally to a surgical clamp for use in mounting a surgical apparatus within a surgical site. More particularly, the present invention relates to a clamping device that precisely repositions a surgical apparatus in a selected position within a surgical site.  
      Many surgical procedures that are performed minimize access to a surgical site to minimize trauma to a patient. An exemplary procedure where access to the surgical site is minimized is a spinal procedure performed within a spinal cavity.  
      After the incision is made, a hole is bored through a vertebrae making up a portion of the spinal column. A surgical apparatus is typically positioned in a selected position within the hole to perform the initial steps of the surgical procedure.  
      Once initial steps of the surgical procedure are performed, the surgical apparatus is removed from the surgical site to provide access for additional surgical equipment. The additional surgical equipment is used to perform additional steps in the procedure. After the additional steps have been performed, the original surgical apparatus is precisely repositioned in the selected position within the surgical site to prevent additional trauma from occurring to the spinal cavity.  
      The surgical apparatus is typically clamped in the selected position to a support rod that extends over the surgical site. The support rod is clamped to a surgical support apparatus that is positioned about the surgical site. The surgical apparatus is removed from the surgical site by either removing the surgical apparatus from the support rod or removing the support rod from the surgical support apparatus.  
      By removing the surgical apparatus from the support rod or moving the surgical rod with respect to the surgical support apparatus, precisely repositioning the surgical apparatus in the selected position within the surgical site is difficult. Therefore, the patient may incur additional unnecessary trauma from the imprecise repositioning of the surgical apparatus within the surgical site.  
     SUMMARY OF THE INVENTION  
      The present invention includes a device for positioning a surgical apparatus in a selected position within a surgical site. The device includes a housing attached to a rod positioned over the surgical site. The housing includes an internal cavity into which a force providing mechanism is positioned. A clamping mechanism is attached to the housing wherein the clamping mechanism includes a bore for engaging the surgical apparatus. The force providing mechanism moves to secure the surgical apparatus to the clamping mechanism in the selected position within the surgical site. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view of the clamping device of the present invention proximate a surgical site.  
       FIG. 2  is a partial exploded view of the clamping device of the present invention.  
       FIG. 3  is an exploded view of the clamping device of the present invention.  
       FIG. 4  is a cut away view of the clamping device of the present invention.  
       FIG. 5  is a sectional view of the clamping member within the housing of the clamping device of the present invention.  
       FIG. 6  is a perspective view of an alternative embodiment of the clamping device of the present invention.  
       FIG. 7  is an exploded view of the alternative embodiment of the clamping device of the present invention.  
       FIG. 8  is a cut-away view of the alternative embodiment of the clamping device of the present invention.  
       FIG. 9  is a perspective view of another alternative embodiment of the present invention.  
       FIG. 10  is an exploded view of the alternative embodiment of the present invention.  
       FIG. 11  is a perspective view of another alternative embodiment of the present invention.  
       FIG. 12  is an exploded view of the alternative embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      A surgical apparatus-retaining device of the present invention is generally illustrated at  10  in  FIG. 1 . The surgical apparatus-retaining device  10  secures a surgical apparatus  24  in a selected location within a surgical site  12 . A housing  22  of the surgical apparatus-retaining device  10  is fixedly attached to an end of a support rod  16  that extends over the surgical site  12  where the support rod  16  is attached to a support apparatus  18  with a clamp  20 . The support apparatus  18  is attached to a field post  17  that is attached to a rail  13  of a surgical table  11 . The surgical apparatus-retaining device  10  allows the surgical apparatus  24  to be removed from the surgical site  12  and precisely repositioned in the selected location within the surgical site  12  provided the surgical apparatus-retaining device  10  remains stationary during a surgical procedure.  
      Referring to  FIGS. 2-5 , the surgical apparatus  24  is positioned in the selected position by positioning a shaft  26  of the surgical apparatus  24  through a through bore  30  of a cylindrical extension  28  that is attached to the housing  22 . The through bore  30  intersects a cavity  23  of the housing  22  where the through bore  30  is aligned with a slot  34  within an actuating mechanism  32  positioned within the cavity  23  of the housing  22  as best illustrated in  FIG. 4 . When the actuating mechanism  32  is positioned in a first non-clamping position, a generally circular opening  36  at an end of the slot  34  aligns with the through bore  30  such that a head  27  of the shaft  26  passes through the generally circular opening  36  and into a void  38  of the actuating mechanism  32 .  
      The head  27  of the shaft  26  preferably has a generally circular cross-section that is positionable within the generally circular opening  36 . However, a different cross-sectionally configured head and a differently configured opening that accepts the head are within the scope of the present invention.  
      The actuating mechanism  32  includes a shaft  40  positioned about an axis  42  of the actuating mechanism  32  where the shaft  40  extends through a through hole  46  in an upper wall  44  attached to an end of the housing  22 . A hub  48  is positioned over the shaft  40  where the hub  48  includes a generally cylindrical recess  50  that accepts the shaft  40 . The hub  48  is attached to the shaft  40  by a pin  52  that is inserted into aligned through bores  54  positioned on opposing sides of the recess  50  and a bore  56  of the shaft  40 .  
      With the shaft  40  fixedly attached to the hub  48  by the pin  52 , the actuating mechanism  32  is captivated within the cavity  23  by the upper wall  44  and the hub  48 . The upper wall  44  prevents the actuating mechanism  32  from exiting the cavity  23  through the top end of the housing  22  and the hub  48  engages the upper wall  44  to prevent the actuating mechanism  32  from falling out of the cavity  23  through a bottom end.  
      Rotation of the hub  48  and the actuating mechanism  32  about the axis  42  is limited by a stop  58  extending from the upper wall  44  and into an arcuate groove  60  of the generally cylindrical recess  50 . The stop  58  limits movement of the hub  48  and the actuating mechanism  32  by engaging either a first end  62  or a second end  64  of the arcuate groove  60  which corresponds to the actuating mechanism  32  being in either a first non-clamping position or a second clamping position, respectively.  
      With the actuating mechanism  32  in the first non-clamping position, the generally circular opening  36  of the slot  32  is aligned with the through bore  30  of the cylindrical extension  28 . The shaft  26  of a surgical apparatus  24  is positioned within the through bore  30  of the cylindrical extension  28  wherein the head  27  of the shaft  26  is positioned through the circular opening  36  of the slot  34  and within the void  38  of the actuating mechanism  32 . With the shaft  26  positioned within the through bore  30  and the head  27  positioned within the void  38 , an annular groove  25  proximate the head  27  is aligned with the slot  34 .  
      As the actuating mechanism  32  is rotated from the first non-clamping position to the second clamping position, the annular groove  25  moves along the slot  34  and an inner surface  66  of a wall  68  defining a portion of the void  38  engages the head  27  and draws the head  27  into the void  38 . The thickness of the wall  68  adjacent the slot  34  increases from a first end  33  adjacent the circular opening  36  to a location  35 . A rotatable wedge portion  67  that when moved increases its thickness (or width) thereby generating a force on the head  27  to draw the head  27  within the void  38  while the annular groove  25  moves along the slot  34  as the actuating mechanism  32  is rotated from the first non-clamping position to the second clamping position.  
      When the actuating mechanism  32  is moved to the second clamping position, a frusto-conical surface  29  of the shaft  26  frictionally engages a frusto-conical surface  31  of the through bore  30 . The location  35  is that position on the wedge portion  67  where the wedge portion  67  cannot be moved further due to the engagement of the surface  31  with the surface  29 . The frictional engagement of the frusto-conical surfaces  29 ,  31  secures the surgical apparatus  24  in the selected position. Preferably, a conduit  21  is attached to the shaft  26 , although any surgical apparatus having a similarly configured shaft  26  is securable within the surgical apparatus-retaining device  10 . The conduit  21  represents conventional surgical apparatus such as, but not limited to, retractors, endoscopes, arthroscopes, surgical microscopes, bronchoscopes, colonoscopes, proctoscopes and the like.  
      In operation, the surgical apparatus-retaining device  10  is secured in a selected position proximate a surgical site  12  by clamping the support rod  16  to support apparatus  18 . A handle  47  attached to the hub  48  is moved which rotates the actuating mechanism  32  into the first non-clamping position where the generally circular opening  36  of the slot  34  is aligned with the through bore  30  of the cylindrical extension  28 .  
      The shaft  26  of the surgical apparatus  24  is positioned within the through bore  30  of the cylindrical extension  28  and the head  27  is positioned within the void  38  such that the annular groove  25  is aligned with the slot  34 . With the actuating mechanism  32  in the first non-clamping position, the shaft  26  is rotatable within the through bore  30  and the surgical apparatus  24  is positioned into a selected position within a surgical site  12 .  
      With the surgical apparatus  24  positioned into the selected position within the surgical site  12 , the handle  47  is moved which rotates the hub  48  and the actuating mechanism  32  from the first non-clamping position toward the second clamping position. As the actuating mechanism  32  is rotated, the annular groove  25  moves along the slot  34  and the inner surface  66  engages the head  27  and draws the head  27  into the void  38 .  
      With the actuating mechanism  32  in the second clamping position, the frusto-conical surface  29  of the shaft  26  frictionally engages the frusto-conical surface  31  of the through bore  30 . The frictional engagement of the frusto-conical surfaces  29 ,  31  fixedly retains the surgical apparatus  24  in the selected position.  
      The surgical apparatus  24  is removable from the surgical site by moving the handle  47  such that the actuating mechanism  32  is positioned into the first non-clamping position. With the actuating mechanism  32  in the first non-clamping position, the circular opening  36  of the slot  34  is aligned with the through bore  36 . Manual force is applied to the surgical apparatus  24  to remove the head  27  from the void  38  and the shaft  26  from the through bore  30 .  
      The surgical apparatus  24  can be repositioned precisely in the same location in the surgical site  12  by retaining the surgical apparatus-retaining device  10  in the selected position proximate the surgical site  12 . With the surgical apparatus-retaining device  10  in the selected position and the actuating mechanism  32  in the first position, the shaft  24  of the surgical apparatus is positioned within the through bore  30  with the head  27  positioned within the void  38  and the annular groove  25  aligned with the slot  34 .  
      The actuating mechanism  32  is rotated into the second clamping position where the inner surface  66  draws the head  27  into the void  38  such that the frusto-conical surface  29  of the shaft  26  is forced into a frictional engagement with the frusto-conical surface  31  of the through bore  30 . With the frusto-conical surfaces  29 ,  31  frictionally engaged, the surgical apparatus  24  is precisely relocated in the selected position within the surgical site  12 .  
      An alternative embodiment of the surgical apparatus-retaining device of the present invention is generally illustrated at  110  in  FIG. 6 . The surgical apparatus-retaining device  110  secures a surgical apparatus  112  in a selected location within a surgical site (not shown). A housing  114  of the surgical apparatus-retaining device  110  is fixedly attached to an end of a support rod  116  that extends over the surgical site where the support rod  116  is attached to a support apparatus with a clamp as previously illustrated in  FIG. 1 .  
      The surgical apparatus  112  is positioned within a socket  122  of a clamping member  120  extending from the housing  114  by applying manual force substantially perpendicular to a back surface  124  of the socket  122  (or within a substantially 180° range from the back surface) that overcomes a bias of a compression spring  126  positioned between the clamping member  120  and a follower  128  positioned within an internal void  115  of the housing  114 . By socket is meant an opening or a cavity into which an inserted part, such as a surgical apparatus, is designed to fit and wherein the surgical apparatus can be inserted into the socket from an infinite number of directions in a 180° range starting from a substantially parallel position to the back surface of the socket to a position substantially perpendicular to the back surface and continuing to position again substantially parallel to the back surface of the socket.  
      The clamping member  120  is operably attached to the follower  128  with a threaded bolt  130  positioned through a through bore  132  in the clamping member  120  that threadably engages a threaded bore  134  within the follower  128 . The clamping member  120  is positioned within the housing  114  through a bore  138  of a bushing  136 .  
      The bushing  136  includes a cylindrical portion  140  positioned within an internal cavity  115  of the housing  114  through a through hole  142  of a plate  144  that is attached to the housing  114 . An annular groove  146  on the cylindrical portion  140  is positioned within the internal cavity  115  and a snap ring  148  is positioned within the annular groove  146  to rotatably captivate the bushing  136  to the housing  114 .  
      An extension  150  of the clamping member  120  is positioned within a slot  152  of the bushing  136  proximate the through bore  138 . The extension  150  has a substantially complementary configuration to a surface  154  defining the slot  152  where the extension  150  engages the surface  154  to rotatably fix the clamping member  120  in relationship to the bushing  136 .  
      With the surgical apparatus  112  with the socket  122 , the compression spring  126  biases the clamping member  120  toward the bushing  136  to constrict an opening  123  of the socket  122  and retain the surgical apparatus  112  within the socket  122 . With the surgical apparatus  112  retained within the socket  122 , the surgical apparatus  112  is slidably positionable along an axis  113  and is rotatable along with the bushing  136  and the clamping member  120  with respect to the housing  114  such that the surgical apparatus  112  is positioned into a selected position.  
      The surgical apparatus  112  is fixed in the select position with a camming pin  156  positioned through through bores  117  of the housing  114  opposite each other and a through bore  127  of the follower  128 . The camming pin  156  includes proximal and distal end portions  158 ,  160  and an intermediate portion  162  that are adjacent one to another. The proximal end portion  158  and the intermediate portion  162  are generally cylindrical in configuration. The distal end portion  160  has arcuate portions  164  separated by flat sides  166  that allow the distal end portion  160  to pass through the through bore  127  within the follower  128 . The proximal and distal end portions  158 ,  162  are centered about a rotational axis  168  of the camming pin  156  and are captivated within the first and second through bores  117 .  
      The captivated proximal and distal end portions  158 ,  162  rotatably support the intermediate portion  162  within the through bore  127  of the follower  128  where the intermediate portion  162  is eccentrically coupled between the proximal and distal end portions  158 ,  162 . The intermediate portion  162  includes a camming surface  161  and has an axis  170  that is spaced from the rotational axis  168  the camming pin  156  by a selected distance. The distance separating the rotational axis  168  of the camming pin  156  and the axis  170  of the intermediate portion  160  generally determines the maximum distance that the camming pin  156  moves the follower  128  within the internal void  115  of the housing  114 .  
      As the camming pin  156  is moved from a first non-clamping position where the surgical apparatus  112  is positionable within the surgical site to a second clamping position, the camming surface  161  of the intermediate portion  160  engages the through bore  127  of the follower  128  and forces the follower  128  away from the bushing  136  and the clamping member  120 . As the follower  128  is forced away from the bushing  136  and the clamping member  120 , a head  131  of the bolt  130  engages a shoulder  133  of the through bore  134  and forces the clamping member  120  into the bushing  136 .  
      The force created by the bolt  130  upon the clamping member  120  creates the frictional engagement between an arcuate upper portion  174  of a clamping surface  172 , the surgical apparatus  112  and a top surface  137  of the bushing  136 . The surgical apparatus  112  also forces the bushing  136  into a frictional engagement between the plate  144  and the surgical apparatus  112 .  
      To remove the surgical apparatus  112  from the surgical apparatus-retaining device  116 , the camming pin  156  is positioned from the second clamping position to the first non-clamping position where the follower  128  is forced toward the bushing  136  and the clamping member  120  and wherein the head  131  of the bolt  130  disengages the shoulder  133 . With the camming pin  156  in the first non-clamping position, the compression spring  126  biases the clamping member  120  toward the clamping position to slidably retain the surgical apparatus  112  within the socket  122 . With the camming pin  156  in the first position, the bushing  136  is rotatable within the housing  114 , the clamping member  160  is slidable within the bushing  136  and the surgical apparatus  112  is removable from the socket  122  with manual force.  
      Another alternative embodiment of the surgical apparatus-retaining device of the present invention is generally illustrated in  FIG. 8  at  210 . The surgical apparatus-retaining device  210  secures a surgical apparatus  212  in a selected location within a surgical site. A housing  216  of the surgical apparatus-retaining device  210  is fixedly attached to an end of a support rod  214  that extends over the surgical site where the support rod  214  is fixedly attached to a support apparatus (not shown) with a clamp (not shown).  
      The surgical apparatus  212  is positioned within a socket  220  within a distal portion  222  of a clamping member  218 . A proximal cylindrical portion  224  of a clamping member is positioned within an internal cavity  217  of the housing  216  between a follower  230  and a lip  226  of the housing  216  where the cylindrical portion  224  is rotatable within internal cavity  217 .  
      Referring to  FIGS. 8-10 , the follower  230  includes a through bore  232  that is aligned with through bores  215  opposite each other within the housing  216 . A camming pin  236  is positioned through the bores  215  of the housing  216  and the through bore  232  of the follower  230 .  
      A bore  225  axially located within the cylindrical portion  224  intersects the socket  220 . A clamping pin  240  is disposed within the bore  225  where an end  242  of the clamping pin  240  is disposed proximate the socket  220  and a head  244  of the clamping pin  240  is positioned within a “T” shaped channel  231  within the follower  230 . The “T” shaped channel  231  engages the head  244  and retains the clamping pin  240  to the follower  230 .  
      The surgical apparatus  212  is fixed in a selected position by positioning the camming pin  236  from a first non-clamping position where the surgical apparatus  212  is movable within the socket  220  to a second clamping position where the surgical apparatus  212  is secured within the socket  220  in a selected position. The camming pin  236  includes proximal and distal end portions  238 ,  240  and an intermediate portion  242  that are adjacent one to another. The proximal end portion  238  and the intermediate portion  242  are generally cylindrical in shape. The distal end portion  240  has arcuate portions  244  separated by flat sides  246  that allow the distal end portion  240  to pass through the through bore  232  within the follower  230 . The proximal and distal end portions  238 ,  240  are centered about a rotational axis  248  of the camming pin  236  and are captivated within the first and second through bores  215 .  
      The captivated proximal and distal end portions  238 ,  240  rotatably support the intermediate portion  242  within the through bore  232  of the follower  230  where the intermediate portion  242  is eccentrically coupled between the proximal and distal end portions  238 ,  240 . The intermediate portion  242  includes a camming surface  250  and has an axis  252  that is spaced from the rotational axis  240  of the camming pin  236  by a selected distance. The distance separating the rotational axis  248  of the camming pin  236  and the axis  252  of the intermediate portion  242  generally determines the maximum distance that the camming pin  236  moves the follower  230  within the housing  216 .  
      As the camming pin  236  is rotated from a non-clamping to a clamping position, the follower  230  is forced into contact with the cylindrical portion  224  wherein the cylindrical portion  224  is frictionally engaged between the follower  230  and the lip  226 . The follower  230  engages the head  244  of the shaft  240 , positioned within the “T” shaped channel  231 , and forces the end  242  into the socket  220  such that the surgical apparatus  212  is frictionally engaged between an arcuate upper surface  260  defining a portion of the socket  220  and the end  242  of the shaft  240 .  
      In operation, the surgical apparatus-retaining device  210  is secured in a selected position about a surgical site by clamping the support rod  216  to the support apparatus (not shown). The camming pin  236  is positioned into the first non-clamping position wherein the end  242  of the shaft  240  is positioned away from the socket  220 . The surgical apparatus  212  is positioned within the socket  220  and the clamping member  218  is rotated within the housing  216  such that the surgical apparatus  212  is in the selected position.  
      A handle  235  which is attached to the camming pin  236  is moved such that the camming pin  236  is rotated from the first non-clamping position to the second clamping position. As the camming pin  236  is rotated into the second clamping position, the follower  230  is forced into the cylindrical portion  224  and frictionally engages the cylindrical portion  224  between the lip  226  and the follower  230 . The frictional engagement of the cylindrical portion  224  between the follower  230  and the lip  226  fixes the position of the clamping member  218  with respect to the housing  216 .  
      As the follower  230  is moved into contact with the cylindrical portion  224 , the follower  230  engages the head  244  of the shaft  240  and forces the end  242  into the socket  220 . The surgical apparatus  212  is frictionally engaged between the arcuate upper surface  260  and the end  242  of the shaft  240 .  
      The surgical apparatus  212  is removed from the socket  220  by rotating the camming pin  236  from the second clamping position to the first non-clamping position where the end  242  of the shaft  240  is removed from the socket  220 . With the end  242  removed from the socket  240 , the surgical apparatus  212  is removed from the socket  220  with manual force.  
      The surgical apparatus  212  is repositionable in the selected position by positioning the surgical apparatus  212  in the socket  240  and rotating the camming pin  236  from the first non-clamping to the second clamping position. Provided the surgical apparatus-retaining device  210  remains stationary proximate the surgical site, the surgical apparatus  212  is repositionable in the selected position.  
      Another alternative embodiment of the clamping device of the present invention is generally illustrated in  FIG. 11  at  310 . The surgical apparatus-retaining device  310  secures a surgical apparatus  312  in a selected location within a surgical site. A housing  316  of the surgical apparatus-retaining device is fixedly attached to an end of a support rod  314  that extends over a surgical site where the support rod  314  is attached to a support apparatus (not shown) with a clamp (not shown).  
      Referring to  FIGS. 11 and 12 , the surgical apparatus  312  includes a conduit  318 . A through bore  322  of the conduit  318  provides access to the surgical site and retains another surgical apparatus (not shown) within the surgical site.  
      The conduit  318  is attached to a cylindrical portion  322  of the surgical apparatus  316  with a shaft  320  positioned through a constricted opening  324  of a cylindrical extension  326  attached to the housing  316 . The cylindrical portion  322  is rotatably positionable within the cylindrical extension  326 .  
      The surgical retaining apparatus  312  is secured in a selected position by forcing an end  332  of a clamping pin  360  operably attached to a follower  342  into contact with the cylindrical portion  322  and creating a frictional engagement between a lip  336  constricting the opening  324  to the cylindrical extension  326 , the cylindrical portion  322  and the end  332  of the clamping pin  330 .  
      A head  335  of the clamping pin  330  is positioned within a “T” shaped channel  344  of the follower  342 . As the follower  342  is moved into a clamping position with a camming pin  346 , a surface  343  defining the “T” shaped channel  344  engages the head  335  of the pin  330  and forces the end  332  of the clamping pin  330  into the cylindrical portion  324 . The cylindrical portion  324  is fixed in a selected position by a frictional engagement between the shoulder  338  and the end  332  of the clamping pin  330 .  
      The camming pin  346  is positioned through the bores  349  of the housing  316  and a through bore  343  of the follower  342 . The camming pin  346  includes proximal and distal end portions  348 ,  350  and an intermediate portion  352  that are adjacent one to another. The proximal end portion  348  and the intermediate portion  352  are generally cylindrical in shape. The distal end portion  350  has arcuate portions  354  separated by flat sides  356  that allow the distal end  350  portion to pass through the through bore  343  within the follower  342 . The proximal and distal end portions  348 ,  350  are centered about a rotational axis  358  and are captivated within the first and second through bores  349 .  
      The captivated proximal and distal end portions  348 ,  350  rotatably support the intermediate portion  352  within the through bore  343  of the follower  342  where the intermediate portion  352  is eccentrically coupled between the proximal and distal end portions  348 ,  350 . The intermediate portion  352  includes a camming surface  353  and has an axis  360  that is spaced from the rotational axis  358  the camming pin  346  by a selected distance. The distance separating the rotational axis  358  of the camming pin  346  and the axis  360  of the intermediate portion  352  generally determines the maximum distance that the camming pin  346  moves the follower  342  within the housing  316 .  
      With the camming pin  346  a first non-clamping position the cylindrical portion  324  is rotatable within the cylindrical extension  326 . With the camming pin  346  in a second clamping position the cylindrical portion  324  is secured between the lip  338  and the end  332  of the clamping pin  330 .  
      In operation, the surgical apparatus-retaining device  310  is secured in a selected position within a surgical site by clamping the support rod  314  to the support apparatus (not shown). A handle  347  which is attached to the camming pin  346  is moved which rotates the camming pin  346  into the first position where the surgical apparatus  312  is rotatable with respect to the housing. With the camming pin  346  in the first position, the surgical apparatus  312  is rotated into a selected position.  
      With the surgical apparatus  312  in the selected position, the camming pin  346  is rotated into the second clamping position. In the second clamping position the cylindrical portion  322  of the surgical apparatus  312  is frictionally engaged between the lip  338  and the end  332  of the clamping pin  330 .  
      Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.