Abstract:
A surgical joint includes a first clamping member comprising a first clamping surface for engaging a first surgical rod and an attachment end. A second clamping member is mounted with respect to the first clamping member wherein the second clamping member comprises a second clamping surface for engaging a second surgical rod. A shaft is disposed through and positioned within the attachment end of the first clamping member and wherein the shaft is in communication with the second clamping member. A force providing mechanism is disposed between the first and second clamping members and disposed about the shaft wherein when the force providing mechanism and the shaft are movable with respect to each other and place the first and second clamping members in either a non-clamping position or a clamping position.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
   None. 
   BACKGROUND OF THE INVENTION 
   The present invention relates generally to a captivated clamp for use in mounting surgical retractors with respect to an operating table. More particularly, the present invention relates to a clamp that is positioned into a clamping position with a wedge. 
   Prior to performing a surgical procedure requiring retraction, a retractor support apparatus is typically disposed about the surgical site. Retractor clamps are commonly used to mount the retractor support apparatus with respect to an operating table. Retractor clamps are also used to attach surgical retractors to the retractor support apparatus. Some retractor clamps are manufactured in a captivated configuration so that users cannot disassemble the retractor clamp. 
   A retractor clamp typically includes a first clamping member, a second clamping member and a handle. A typical configuration for a clamping member is to have the clamping member fabricated from a unitary structure that is generally in the shape of the letter “U”. In each of the retractor clamps, the object to be clamped is placed between the legs of the U-shaped structure so that the object is proximate the base of the U-shaped structure. Movement of the legs of the U-shaped structure towards each other causes the object to be clamped with respect to the clamping member. 
   The use of clamping members having U-shaped structures has some disadvantages in particular surgical procedures. First, the U-shaped structure must be disposed over an end of a retractor support apparatus and slid into a desired position. When previously placed retractor clamps are disposed between the end of the support arm and the desired location, the interfering clamps must be removed to allow the additional surgical clamp to be disposed in the desired location. Having to disassemble at least a portion of the surgical support apparatus about a surgical site to add additional retractors adds unnecessary additional time and expense to the surgical procedure. 
   Additionally, the second U-shaped structure and the handle are typically disposed above the first U-shaped structure and the retractor support arm. Because the second U-shaped structure and the handle are located above the surgical support arm, the second U-shaped structure and the handle may obstruct access to the surgical site during some surgical procedures. 
   SUMMARY OF THE INVENTION 
   The present invention includes a surgical joint having a first clamping member comprising a first clamping surface for engaging a first surgical rod and an attachment end. A second clamping member is mounted with respect to the first clamping member where the second clamping member comprises a second clamping surface for engaging a second surgical rod. A shaft is disposed through and positioned within the attachment end of the first clamping member where the shaft is in communication with the second clamping member. A force providing mechanism is disposed between the first and second clamping members and disposed about the shaft where the force providing mechanism and the shaft are movable with respect to each other and place the first and second clamping members in either a non-clamping position or a clamping position. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of the surgical clamp of the present invention in a non-clamping position. 
       FIG. 2  is a perspective view of the surgical clamp of the present invention in a clamping position. 
       FIG. 3  is an exploded view of the surgical clamp of the present invention. 
       FIG. 4  is a perspective view of an actuating mechanism of the surgical clamp of the present invention. 
       FIG. 5  is a top view of the actuating mechanism of the surgical clamp of the present invention. 
       FIG. 6  is a partially exploded perspective view of the first alternative embodiment of the surgical clamp of the present invention. 
       FIG. 7  is a side view of the first alternative embodiment of the surgical clamp of the present invention. 
       FIG. 8  is a sectional view of the second alternative embodiment of the surgical clamp of the present invention. 
       FIG. 9  is an exploded view of the second alternative embodiment of the surgical clamp of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention includes a low profile surgical clamp generally illustrated in  FIG. 1  at  10 . The clamp  10  is particularly suited for mounting a retractor (not shown) with respect to an operating table (not shown). The clamp  10  includes a first clamping member  12  having a first clamping surface  14  and a second clamping member  16  having a second clamping surface  18 . Other components may be substituted for the second clamping member  16  such as, but not limited to, permanently attached retractors, or retractors that are attached using other types of clamps or fasteners. 
   To position the clamp  10  within the surgical site, a clamping end  24  of the first clamping member  12  is positioned proximate a retractor support arm  11 . The first clamping surface  14  proximate the clamping end  24  is disposed about the portion of the retractor support arm  11 . 
   The first clamping member  12  also includes an attachment end  26  and a fulcrum portion  28  between the clamping end  24  and the attachment end  26 . The first clamping member  12  has a recess  30  defined by an upper leg portion  32  and a lower leg portion  34  proximate the attachment end  26 . 
   The fulcrum portion  28  extends between the upper leg portion  32  and the lower leg portion  34  as best illustrated in  FIG. 3 . The fulcrum portion  28  allows the upper leg portion  32  to move with respect to the lower leg portion  34  so that the retractor support arm  11  may be clamped within the first clamping surface  14 . 
   An actuating mechanism  80  is disposed within the recess  30  between the upper leg portion  32  and the lower leg portion  34  of the first clamping member  12  as illustrated in  FIGS. 1 and 2 . The actuating mechanism  80  preferably is a wedge. By the term wedge is meant a component that progressively increases in cross-sectional thickness such that when the wedge is moved or rotated in a restricted space, the movement or rotation of the wedge causes progressive increase in thickness to cause a force to be applied, such as a leverage action, to spread apart leg portions of the clamp. The wedge may take on forms other than those specifically described herein. 
   The wedge  80  is movable within the recess  30  and forces the upper and lower leg portions  32 ,  34  apart and causes the fulcrum portion  28  to flex. As the fulcrum portion  18  flexes, the first clamping member  12  constricts. When constricted, the first clamping surface  14  frictionally engages the retractor support arm  11  in a clamped relationship. 
   The first clamping surface  14  is configured to generally conform to the cross-sectional configuration of the retractor support arm  11 , but may be configured to conform to other shaped cross-sections. In a preferred embodiment, the first clamping surface  14  conforms to a substantially circular cross-sectional configuration of the retractor support arm  11 . 
   Referring to  FIG. 3 , the first clamping surface  14  defines a clamping slot  38  that permits the first clamping member  12  to be placed on the retractor support arm  11  without moving any other surgical equipment that has been previously disposed upon the retractor support arm  11 . When the clamp  10  is in a non-clamping position, the first clamping member  12  is retained upon the retractor support arm  11  by a constricted entrance  39  to the clamping slot  38 . In an exemplary embodiment, a bead or raised surface  40  is disposed along a length of resilient portions  35 ,  37  that move as the retractor support arm  11  is positioned within the clamping slot  38  where the bead  40  constricts the entrance  39 . However other devices that constrict the entrance  39  to the clamping slot  38  are within the scope of the present invention including, but not limited to, a clip, a roller or a spring loaded device. 
   The constricted entrance  39  provides a preliminary clamping force around the portion of the retractor support arm  11  such that the constricted entrance  39  to the clamping slot  38  prevents the clamp  10  from slipping off the retractor support arm  11  when the clamp  10  is in non-clamping position. The entrance  39  of the clamping slot  38  should not be so constricted to prevent use of manual force to position the first clamping member  12  about the portion of the retractor support arm  11 . However, the entrance  39  of the clamping slot  38  should be sufficiently constricted to prevent the first clamping member  12  from accidentally slipping off of the retractor support arm  11 . An exemplary amount of constriction of the entrance  39  of the clamping slot  38  is between about 0.010 inches and 0.020 inches and preferably about 0.015 inches. 
   The second clamping member  16  extends through a through bore  48  defined by a frusto-conical surface  49  within the upper leg portion  32  of the first clamping member  12 . The second clamping member  16  includes a frusto-conical surface  50  at a proximal end  52  that cooperates with the frusto-conical surface  49 . 
   With the second clamping member  16  being positioned within the upper leg portion  32 , an annular groove  56  on the second clamping member  16  is positioned above an upper surface  33  of the upper leg portion  32 . A snap ring  58  is disposed within the annular groove  56  and rotatably captivates the second clamping member  16  within the upper leg portion  32  of the first clamping member  12  as illustrated in  FIGS. 1 and 2 . 
   Referring to  FIGS. 1-3 , the second clamping surface  18  is positioned on a distal end portion  54 . A retractor handle  20  is disposed within an opening  17  defined by the second clamping surface  18 . An arcuate upper portion  62  and an end  102  of the shaft  100  constrict an entrance  19  of the opening  17  and retain the retractor handle  20  within the second clamping surface  18 . Although the second clamping member  16  is described and illustrated in the drawings as retaining and clamping a retractor handle  20 , the second clamping member  16  can also retain and clamp other surgical devices. By surgical devices is meant any element that is useful in conducting a surgical procedure including, but not limited to, a retractor support apparatus, a retractor or any other medical instrument that is used during a surgical procedure such as a camera, a light or a catheter. 
   The second clamping member  16  is positioned into a clamping position at approximately the same time that the wedge  80  forces the first and second leg portions  32 ,  34  apart. When the second clamping member  16  is in the clamping position, the second clamping member  16  is non-rotatably fixed with respect to the first clamping member  12  and the retractor handle  20  is frictionally engaged within the second clamping surface  18 . 
   In the clamping position, the second clamping member  16  is rotatably fixed within the upper leg portion  32  by a frictional engagement of the cooperating frusto-conical surfaces  49 ,  50 . The retractor handle  20  is frictionally engaged between the arcuate upper portion  62  and an end  102  of a shaft  100  positioned through a through bore  72 . The through bore  72  extends through the second clamping member  16  along an axis  73  and intersects a bottom portion  61  of the clamping surface  18 . 
   Referring to  FIG. 3 , an upper substantially circular cross-section portion  111  of a shaft  100  extends through an elongated slot  42  within the lower leg portion  34 , a washer  98 , a compression spring  109 , a through bore  94  of the wedge  80 , the through bore  48  of the upper leg portion  32  and into the through bore  72  of the second clamping member  16 . The end  102  of the upper portion  111  extends into the opening  17 . 
   A lower portion  110  of the shaft  100  captivates the washer  98  and the compression spring  109  between the lower leg portion  34  and the wedge  80 . With the shaft  100  disposed within the clamp  10 , a shoulder  113  is positioned proximate the proximal end  52  of the second clamping member  16 . The shoulder  113  cooperates with the proximal end  52  to prevent the shaft  100  from being further inserted into the clamp  10 . 
   Referring to  FIGS. 1-3 , the washer  98  is positioned between a bottom surface  96  of the wedge  80  and the lower leg portion  34 . The washer  98  prevents wear of the lower leg portion  34  and the wedge  80  as the clamp  10  is used over time. 
   The lower portion  110  of the shaft  100  has substantially flat, parallel sides  112 ,  114 , respectively, that cooperate with substantially flat, parallel sides  44 ,  46 , respectively, of the elongated slot  42 . The cooperation of the lower portion  110  within the elongated slot  42  prevents rotation of the shaft  100  within the clamp  10  while allowing the shaft  100  to move slightly with respect to the first and second clamping members  12 ,  16 . 
   The shaft includes a bore  106  that is in a substantially perpendicular relationship with the axis  73 . With the lower portion  110  of the shaft  100  positioned within the elongated slot  42 , the bore  106  is positioned between the proximal end  52  of the second clamping member  16  and the wedge  80 . A pin  108  is positioned through the bore  106  in the shaft  100 . 
   The compression spring  109  biases the wedge  80  toward the second clamping member  16  such that first and second ramped surfaces  82 ,  84 , respectively, of the wedge  80  engage the pin  108 . The engagement of the pin  108  with the first and second ramped surfaces  82 ,  84 , respectively, of the wedge  80  prevents the shaft  100  from exiting from the lower leg portion  34 . The compression spring  109  also biases the end  102  of the shaft  100  into the opening  17  by forcing the shoulder  113  into the proximal end  52  of the second clamping member  16   
   Referring to  FIGS. 4 and 5 , the wedge  80  includes the first and second ramped surfaces  82 ,  84 , respectively, that are symmetric about the axis  73 . Arcuate indentions  86 ,  90  are located each at a base of the first and second ramped surfaces  82 ,  84 , respectively, and opposite each other. Arcuate indentions  88 ,  92  are located each at an apex of the first and second ramped surfaces  82 ,  84 , respectively, and opposite each other. 
   The pin  108  engages the arcuate indentions  86 ,  90  each at the base of the first and second ramped surfaces  82 ,  84 , respectively, to retain the wedge  80  in a first position where the first and second clamping members  12 ,  16 , respectively are in non-clamping positions. The pin  108  engages the arcuate indentions  88 ,  92  each at the apex of the first and second ramped surfaces  82 ,  84 , respectively, to retain the wedge  80  in a second position where the first and second clamping member  12 ,  16 , respectively, are in clamping positions. 
   In operation, the wedge  80  is positioned in the first position when the pin  108  is engaged with the arcuate indentions  86 ,  90  each at the base of the first and second ramped surfaces  82 ,  84 , respectively, as best illustrated in  FIG. 1 . With the wedge  80  in the first position, the first clamping member  12  and the second clamping member  16  can accept the retractor support arm  11  and the retractor handle  20 , respectively, and the second clamping member  16  is rotatable with respect to the first clamping member  12 . 
   The first clamping member  12  is disposed in a selected position on the retractor support arm  11  by positioning the constricted entrance  39  of the clamping slot  38  proximate the retractor support arm  11 . Manual force is applied to the first clamping member  12  substantially perpendicular to an axis of the retractor support arm  11  to overcome the constricted entrance  39  of the clamping slot  38 , thereby disposing the first clamping member  12  about the retractor support arm  11 . With the wedge  80  in the first position, the first clamping member  12  is slidably positionable on the retractor support arm  11 . 
   With the first clamping member  12  positioned on the retractor support arm  11 , the retractor handle  20  is positioned proximate the constricted entrance  19  of the opening  17  within the second clamping member  16 . Manual force is applied substantially perpendicular to an axis of the retractor handle  20  to overcome the bias of the compression spring  109  and force the end  102  of the shaft  100  from the opening  17  and dispose the retractor handle  20  within the opening  17 . With the retractor handle  20  positioned within the opening  17 , the end  102  of the shaft  100  is biased back into the opening  17  such that the retractor handle  20  is slidably retained within the second clamping member  16 . 
   To position the wedge  80  into the second or clamping position, a handle  22  fixedly attached to the wedge  80  is moved in the direction of arrows  23  as illustrated in  FIG. 1 , which rotates the wedge  80  about the shaft  100  and axis  73 . Although the preferred embodiment includes a rotatable wedge, one skilled in the art will recognize that moving a wedge in other manners such as sliding is also within the scope of the invention. The purpose of the wedge  80  is to increase the wedge&#39;s thickness within the recess  30  to force the upper and lower leg portions  32 ,  34 , respectively, apart. 
   As the wedge  80  is rotated about the shaft  100 , the pin  108  moves along the first and second ramped surfaces  82 ,  84  toward the apexes of the first and second ramped surfaces  82 ,  84 , respectively. As the pin  108  rises on the first and second ramped surfaces,  82 ,  84 , respectively, an increasing force is placed upon the pin  108 . A maximum force is placed upon the pin  108  when the wedge  80  is positioned into the second position when the pin  108  is disposed within the arcuate indentions  88 ,  92  each at the apex of the first and second ramped surfaces  82 ,  84 , respectively, as best illustrated in  FIG. 2 . The wedge  80  includes first and second strengthening portions  83 ,  85  to stiffen the wedge  80  and prevent the wedge  80  from flexing as the wedge  80  is rotated, as best illustrated in  FIGS. 1-5 . 
   Referring to  FIGS. 1 and 2 , as the wedge  80  is rotated from the first position to the second position, the wedge  80  compresses the compression spring  109 , and the distance between the pin  108  and the washer  72  becomes less than the height of the wedge  80 . With the wedge  80  in the second position, the height of the wedge  80  is greater than the distance between the pin  108  and the washer  72 , such that the wedge  80  forces the first and second leg portions  32 ,  34  apart by forcing the shoulder  113  of the shaft into the proximal end  52  of the second clamping member  16  and transferring the force to the first leg portion  32 . With the first and second leg portions  32 ,  34  forced apart, the fulcrum portion  28  flexes which causes the first clamping slot  38  to constrict such that the first clamping surface  14  frictionally engages the retractor support arm  11 . 
   With the wedge  80  in the second position, the shoulder  113  is forced upward and into the proximal end  52  of the second clamping member  16  and creates a frictional engagement between the cooperating frusto-conical surface  49  of the through bore  48  in the upper leg portion  32  and the frusto-conical surface  50  of the second clamping member  16 . The frictional engagement of the frusto-conical surfaces  49 ,  50  prevents rotational movement of the second clamping member  16  with respect to the first clamping member  12 . 
   With the wedge  80  in the second position, the end  102  of the shaft  100  is raised into the opening  17  through the through bore  72 . The raised end  102  of the shaft  100  contacts the retractor handle  20  and creates a frictional engagement between the arcuate upper portion  62  of the second clamping surface  18 , the retractor handle  20  and the end  102  of the shaft  100 . 
   One skilled in the art will recognize that a plane of movement of the handle  22  approximately intersects an axis of the retractor support arm  11  as best illustrated in  FIGS. 1 and 2 . Therefore, the operator can conveniently manipulate the wedge  80  from the first position to the second position by gripping the handle  22  and the retractor support arm  11  with one hand and forcing the handle  22  toward the retractor support arm  11 . 
   The surgical clamp  10  of the present invention also provides a low profile clamping device for conducting the surgical procedure. What is meant by low profile is that the second clamping member  16  and a handle  22  are disposed proximate the retractor support arm  11  as best illustrated in  FIGS. 1 and 2 . By disposing the second clamping member  16  and the handle  22  proximate the retractor support arm  11 , the surgical site remains relatively open and free of obstruction thereby providing better access to the surgical site. 
   An advantage of the clamp  10  of the present invention is that the clamp  10  does not have to be slid along the retractor support arm  11  to a new selected position. The retractor clamp  10  can be repositioned on the support arm  11  by first positioning the wedge  80  into the first position such that the first clamping slot  38  is not constricted and detaching the first clamping member  12  from the retractor support arm  11 . The first clamping member  12  is detachable from the retractor support arm  11  by applying manual force in an opposite direction as used to position the first clamping member  12  on the support arm  11 . After the clamp  10  has been removed from the retractor support arm  11 , the clamp  10  is repositionable on the retractor support arm  11  by positioning an entrance  39  to the clamping slot  38  against the retractor support arm  11  and applying manual force substantially perpendicular to the axis of that portion of the retractor support arm  11 . 
   The retractor handle  20  can also be repositioned within the second clamping member  16  without having to slide the retractor handle  20  with respect to the second clamping surface  18 . The retractor handle  20  is removed from the second clamping member  16  by providing manual force in the opposite direction of the force used to position the retractor handle  20  within the opening  17  of the second clamping member  16 . The retractor handle  20  can be reinserted into the opening  17  by reapplying manual force generally perpendicular to the axis of the retractor handle  20 . 
   The surgical clamp  10  of the present invention, having the first and second clamping surfaces  14 ,  18 , respectively, enables the clamp  10  to be positioned upon the retractor support arm  11  in a selected position. Further, an additional retractor can be easily and conveniently positioned within a surgical site without having to dispose the end of the retractor through the opening  17  defined by the second clamping surface  18 . The convenience of the surgical clamp  10  of the present invention allows the surgical site to be quickly assembled, modified during a surgical procedure, and disassembled, which enables a surgical team to conduct a more efficient surgical procedure. 
   An alternative embodiment of the surgical clamp of the present invention is illustrated in  FIGS. 6 and 7  at  210 . The clamp  210  includes a first clamping member  212  and a second clamping member  216  separated by a washer  220 . A shaft  222  is disposed through the first and second clamping members  212 ,  216 , respectively. The shaft  222  includes an externally threaded portion  224  proximate a first end  226 , a head  228  proximate a second end  227  and an intermediate portion (not shown) between the head  228  and the threaded portion  224 . 
   The threaded portion  224  of the shaft  222  is disposed through an elongated bore  240  within the first clamping member  212  and through a bore  241  within the second clamping member  216 . A nut  225  threadably engages the threaded portion  224  and retains the first and second clamping members  212 ,  216 , respectively, about the shaft  222 . 
   The first clamping member  212  is preferably made of a unitary structure having a surface  214  defining a first clamping slot  221  proximate a first end  215  and a first pivot surface  234  proximate a second end  236  which contacts an upper surface of the washer  220 . The first clamping member  212  includes the elongated bore  240  for accepting the head  228  of the shaft  222 . 
   The first clamping member  212  includes an integral collar  260  that cooperates with a camming pin  242 . The camming pin  242  includes end portions  250 ,  252 , respectively and an intermediate portion  254 . The end portions  250 ,  252  and the intermediate portion  254  are generally cylindrical in shape and are located adjacent one to another. The end portions  250 ,  252  are centered about a rotational axis and are captivated within first and second through bores  262 ,  264 , respectively. The captivated end portions  250 ,  252  rotatably support the intermediate portion  254  within the collar  260  and a through bore (not shown) within the head  228  of the shaft  222 . 
   The shaft  222  is positioned through the elongated bore  240  within the first clamping member  212  including the integral collar  260  and the through bore  241  within the second clamping member  216 , respectively, such that the head  228  is disposed within the elongated bore  240 . The elongated bore  240  is elongated to allow the required movement of a head  228  of the shaft  222  when the clamp  210  is positioned from the first position to the second position and also in the reverse direction. The head  228  includes the through bore (not shown) that is aligned with the first and second through bores  262 ,  264 , respectively, within the collar  260  and engages the intermediate portion  254  of the camming pin  242 . 
   The intermediate portion  254  is eccentrically coupled between the end portions  250 ,  252 , respectively. The intermediate portion  254  includes an outer circumferential surface  256  having an axis that is spaced from the rotational axis the camming pin  242  by a selected distance. The distance separating the axis of the camming pin  242  and the axis of the intermediate portion  256  generally determines the maximum distance that the camming pin  242  moves the shaft  222  relative to the first and second clamping members  212 ,  216 , respectively. Preferably, the distance separating the axis of the camming pin  242  and the axis of the intermediate portion  254  is sufficient to frictionally secure first and second surgical rods  246 ,  248  within the first and second clamping members  212 ,  216 , respectively. 
   The second clamping member  216  is also preferably a unitary structure having a surface  218  defining a second clamping slot  217  proximate a first end  219  and a second pivot surface  230  proximate a second end  232 . The second pivot surface  230  contacts a bottom surface of the washer  220 . 
   In operation, a handle  244 , fixedly attached to the camming pin  242 , is in a first position such that the first and second clamping slots  221 ,  217  of the first and second clamping members  212 ,  216  accept first and second support members  246 ,  248 , all respectively. The movement of the handle  244  from the first position to a second position causes the intermediate portion  254  to engage the shaft  222 . As the shaft  222  is engaged, a force is applied to the first clamping member  212 . 
   The force causes the first clamping member  212  to pivot about the first pivot surface  234  such that the first support member  246  is frictionally engaged between the first clamping member  212  and the upper surface of the washer  220 . The force is also applied to the second clamping member  216  and causes the second clamping member  216  to pivot about the second pivot surface  230  and causes the second support member  248  to be frictionally engaged between the bottom surface of the washer  220  and the second clamping member  216 . 
   Thus, a simple actuation of the handle  244  and the camming pin  242  frictionally clamps the first and second support members  246 ,  248  within the first and second clamping members  212 ,  216 , respectively, in selected rotational and axial positions. Conversely, the opposite movement of the handle  244  and rotation of the camming member  242  moves the head portion  228  of the shaft  222  relative to the first and second clamping members  212 ,  216  to reduce the forces that frictionally bind the first and second support members  246 ,  268  and thereby allow the first and second support members  246 ,  248  to be removed from the first and second clamping surfaces  214 ,  218 , respectively. 
   The surgical clamp  210  enables a physician to quickly and easily adjust and re-adjust the rotational positions of the first and second clamping members  212 ,  216  as well as the position of the first and second support members  246 ,  248 , respectively, within the first and second clamping members  212 ,  216  by providing a force perpendicular to an axis of the first and second surgical rods  246 ,  248 . As a result, the surgeon can easily add an additional retractor where needed by disposing the clamp  210  about the second surgical rod  248  and providing a force perpendicular to an axis of the second support member  248  thereby disposing the second support member within the second clamping slot  217 . 
   Further, the first support member  246 , in this instance a retractor handle, is easily disposed within the first clamping slot  221  without having to dispose an end of the first support member  246  through the first clamping slot  221 . By rotating the handle  244  and camming pin  242  between the first non-clamping position and the second clamping position, the clamp  210  frictionally engages the first surgical rod  246  and the second surgical rod  248 . As a result, adding an additional retractor within a surgical site is simple, quick and does not require the surgical team to break down any of the apparatus surrounding the surgical site. 
   A second alternative embodiment of the surgical clamp of the present invention is generally illustrated in  FIG. 8  at  310 . The clamp  310  includes a first clamping member  312  having a first clamping surface  314  and a second clamping member  316  having a second clamping surface  318 . Other components may be substituted for the second clamping member  316  such as, but not limited to, permanently attached retractors, or retractors that are attached using other types of clamps or fasteners. 
   To position the clamp  310  within the surgical site, a clamping end  324  of the first clamping member  312  is positioned proximate a retractor support arm  311 . The first clamping surface  314  proximate the clamping end  324  is disposed about the portion of the retractor support arm  311  by applying manual force substantially perpendicular to an axis of the retractor support arm  311 . 
   The first clamping member  312  also includes a fulcrum portion  328  proximate the clamping surface  314  and located between an upper leg portion  332  and a lower leg portion  334  as best illustrated in  FIGS. 8 and 9 . The fulcrum portion  328  allows the upper leg portion  332  to move with respect to the lower leg portion  334  so that the retractor support arm  311  may be clamped within the first clamping surface  314 . 
   An actuating mechanism  380  is disposed within a recess  330  defined by the upper leg portion  332  and the lower leg portion  334  of the first clamping member  312  as illustrated in  FIG. 8 . The actuating mechanism  380  preferably is a camming pin. 
   The camming pin  380  is movable within the recess  330  and forces the upper and lower leg portions  332 ,  334  apart and causes the fulcrum portion  328  to flex. As the fulcrum portion  318  flexes, a clamping slot  338  defined by the first clamping surface  314  constricts such that the first clamping surface  314  frictionally engages the retractor support arm  311 . The first clamping surface  314  is configured to generally conform to the cross-sectional configuration of the retractor support arm  311 , but may be configured to conform to other shaped cross-sections. 
   Referring to  FIGS. 8 and 9 , the clamping slot  338  permits the first clamping member  312  to be placed on the retractor support arm  311  without moving any other surgical equipment that has been previously disposed upon the retractor support arm  311 . When the clamp  310  is in a non-clamping position, the first clamping member  312  is retained upon the retractor support arm  311  by a constricted entrance  339  to the clamping slot  338 . A bead or raised surface  340  is disposed substantially along a length of the clamping slot  338  to constrict the entrance  339 . 
   The constricted entrance  339  provides a preliminary clamping force around the portion of the retractor support arm  311  such that the constricted entrance  339  to the clamping slot  338  prevents the clamp  310  from slipping off the retractor support arm  311  when the clamp  310  is in non-clamping position. The entrance  339  of the clamping slot  338  should not be so constricted to prevent use of manual force to position the first clamping member  312  about the portion of the retractor support arm  311 . However, the entrance  339  of the clamping slot  338  should be sufficiently constricted to prevent the first clamping member  312  from accidentally slipping off of the retractor support arm  311 . 
   The second clamping member  316  extends through a through bore  348  defined by a frusto-conical surface  349  within the upper leg portion  332  of the first clamping member  312 . The second clamping member  316  includes a frusto-conical surface  350  at a proximal end  352  that cooperates with the frusto-conical surface  349  of the upper leg portion  332 . 
   With the second clamping member  316  being positioned within the upper leg portion  332 , an annular groove  356  on the second clamping member  316  is positioned above an upper surface  333  of the upper leg portion  332 . A snap ring  358  is disposed within the annular groove  356  that rotatably captivates the second clamping member  316  within the upper leg portion  332  of the first clamping member  312  as illustrated in  FIG. 8 . 
   Referring to  FIGS. 8 and 9 , the second clamping surface  318  is positioned on a distal end portion  354 . A retractor handle  320  is disposed proximate an entrance  319  to an opening  317  defined by the second clamping surface  318 . Manual force is applied to the retractor handle  320  substantially perpendicularly to an axis to position the retractor handle  320  within the opening  317  by displacing an end  402  of a shaft  400  from the opening  317 . The end  402  is positioned into the opening  317  through a through bore  372  extending through the second clamping member  316  along an axis  373  and intersects a bottom portion  361  of the clamping surface  318 . With the end  402  displaced from the opening  317 , the entrance  319  to the opening  317  is not constricted thereby allowing the retractor handle  320  to be disposed within the opening  317 . 
   With the retractor handle  320  positioned within the opening  317 , a compression spring  409 , disposed between the shaft  400  and a spacer  430  that contacts the camming pin  380 , biases the end  402  of the shaft  400  back into the opening  317 . The end  402  and the arcuate upper portion  362  retain the retractor handle within the opening  317  such that the retractor handle is slidably positionable with respect to the second clamping surface  318 . 
   The second clamping member  316  is positioned into a clamping position at approximately the same time that the camming pin  380  forces the first and second leg portions  332 ,  334  apart. When the second clamping member  316  is in the clamping position, the second clamping member  316  is non-rotatably fixed with respect to the first clamping member  312  and the retractor handle  320  is frictionally engaged within the second clamping surface  318 . 
   The camming pin  380  is positionable between a first non-clamping position and a second clamping position. In the first non-clamping position the first and second clamping members  312 ,  316 , respectively, are in a non-clamping position and the second clamping member  316  is rotatable within the first clamping member  312 . In the second clamping position, the retractor support apparatus  311  is frictionally engaged with the first clamping surface  314  and a retractor support handle  320  is frictionally engaged between the arcuate upper portion  362  of the second clamping surface  318  and the end  402  of the shaft  400 . Additionally, the second clamping member  316  is rotatably fixed with respect to the first clamping member  312  by a frictional engagement of the cooperating frusto-conical surfaces  349 ,  350 . 
   The camming pin  380  is positioned within the recess  330  where the camming pin  380  includes a first cylindrical portion  388  and a second cylindrical portion  390  that are separated by the camming surface  382  which has an axis offset from the axis of rotation of the camming pin  380 . Although a specific cam is described and illustrated in the drawings, other cam configurations are included within the present invention. By cam is meant an element having a raised surface or projecting part that when moved or rotated imparts an intermittent, alternate or variable motion. 
   The first and second cylindrical portions  388 ,  390 , respectively, are rotatably positioned within first and second arcuate recesses  436 ,  438 , respectively, within the lower leg portion  334  and first and second arcuate recesses  440 ,  442 , respectively, within a lower portion  404  of the shaft  400 . The first arcuate recesses  436 ,  440 , respectively, cooperate to rotatably retain the first cylindrical portion  388  and the second arcuate recesses  438 ,  442 , respectively, cooperate to rotatably retain the second cylindrical portion  390  such that the camming pin  380  is rotatable between the first and second positions. 
   With the camming pin  380  in the first position, the spacer  430  is positioned on a flat surface  384  of the camming pin  380 . With the spacer  430  positioned on the flat surface  384 , the compression spring  409  biases a shoulder  413  towards the proximal end  350  of the second clamping member  316  and biases the end  402  of the shaft  400  into the opening  317 . A first end of the compression spring  409  is disposed within a cavity  420  of the shaft  400 . A second end of the compression spring  409  is disposed within the cavity  432  within a spacer  430  where the spacer  430  is slidably positionable within the cavity  420 . 
   As the camming pin  380  is rotated into the second position, the spacer  430  is positioned on and raised by the camming surface  382 . As the spacer  430  is raised, the compression spring  409  compresses until an end  431  of the spacer  430  contacts a surface  421  within the cavity  420 . With the surfaces  421 ,  431  contacting and the camming pin  380  in the second clamping position, the shoulder  413  is forced into the proximal end  352  of the second clamping member  316  creating a frictional engagement with the frusto-conical surfaces  349 ,  350 . Additionally, the end  402  of the shaft  400  is forced into the opening  317  such that the retractor handle  320  is secured within the opening  317  by a frictional engagement between the end  402  of the shaft  400 , the retractor handle  320  and the arcuate upper surface  362 . 
   In operation, the camming pin  380  is positioned in the first position when the spacer  430  is positioned on the flat surface  384 . With the camming pin  380  in the first position, the first clamping member  312  and the second clamping member  316  can accept the retractor support arm  311  and the retractor handle  320 , respectively, and the second clamping member  316  is rotatable with respect to the first clamping member  312 . 
   The first clamping member  312  is disposed in a selected position on the retractor support arm  311  by positioning the constricted entrance  339  of the clamping slot  338  proximate the retractor support arm  311 . Manual force is applied to the first clamping member  312  substantially perpendicular to an axis of the retractor support arm  311  to overcome the constricted entrance  339  of the clamping slot  338 , thereby disposing the first clamping member  312  about the retractor support arm  311 . With the camming pin  380  in the first position, the first clamping member  312  is slidably positionable on the retractor support arm  311 . 
   With the first clamping member  312  positioned on the retractor support arm  311 , the retractor handle  320  is positioned proximate the constricted entrance  319  of the opening  317  within the second clamping member  316 . Manual force is applied substantially perpendicular to an axis of the retractor handle  320  to force the end  402  of the shaft  400  from the opening  317  and position the retractor handle  320  within the opening  317 . With the retractor handle  320  positioned within the opening  317 , the compression spring  409  biases the end  402  of the shaft  400  into the opening  317  such that the retractor handle  320  is slidably retained within the second clamping surface  318 . 
   To position the camming pin  380  into the second or clamping position, a handle  322  fixedly attached to the camming pin  380  is moved in the direction of arrows  323  as illustrated in  FIG. 8 , which rotates the camming pin  380  about the first and second cylindrical portions  388 ,  390 , respectively. As the camming pin  380  is rotated about the first and second cylindrical portions  388 ,  390 , the spacer  430  is raised into the cavity  420  and compresses the compression spring  409 . A maximum force is placed upon the spacer  430  and shaft  400  when the camming pin  380  is positioned into the second position when the end  431  of the spacer  430  contacts the surface  421  within the cavity  420  and applies the force to the shaft  400 . 
   Referring to  FIG. 8 , with the camming pin  380  in the second clamping position, a distance between the spacer  430  and the lower leg portion  334  is less than the distance between portions of the cylindrical portions  388 ,  390  within the arcuate recesses  436 ,  438 , respectively, and an upper edge of the camming surface  382  thereby forcing the first and second leg portions  332 ,  334  apart. With the first and second leg portions  332 ,  334  forced apart, the fulcrum portion  328  flexes which causes the first clamping slot  338  to constrict such that the first clamping surface  314  frictionally engages the retractor support arm  311 . 
   With the camming pin  380  in the second position, the shoulder  413  is forced into the proximal end  352  of the second clamping member  316  and creates a frictional engagement between the cooperating frusto-conical surface  349  of the through bore  348  in the upper leg portion  332  and the frusto-conical surface  350  of the second clamping member  316 . The frictional engagement of the frusto-conical surfaces  349 ,  350  prevents rotational movement of the second clamping member  316  with respect to the first clamping member  312 . 
   With the camming pin  380  in the second position, the first end  402  of the shaft  400  is raised into the opening  417  through the through bore  372 . The raised first end  402  of the shaft  400  contacts the retractor handle  320  and creates a frictional engagement between the arcuate upper portion  362  of the second clamping surface  318 , the retractor handle  320  and the first end  402  of the shaft  400 . 
   The retractor clamp  310  can be repositioned on the support arm  311  by first positioning the camming pin  380  into the first position such that the first clamping slot  338  is not constricted and detaching the first clamping member  312  from the retractor support arm  311 . The first clamping member  312  is detachable from the retractor support arm  311  by applying manual force in an opposite direction as used to position the first clamping member  312  on the support arm  311 . After the clamp  310  has been removed from the retractor support arm  311 , the clamp  310  is repositionable on the retractor support arm  311  by positioning an entrance  339  to the clamping slot  338  against the retractor support arm  311  and applying manual force substantially perpendicular to the axis of that portion of the retractor support arm  311 . 
   The retractor handle  320  can also be repositioned within the second clamping member  316  without having to slide the retractor handle  320  with respect to the second clamping surface  318 . The retractor handle  320  is removed from the second clamping member  316  by providing manual force in the opposite direction of the force used to position the retractor handle  320  within the opening  317  of the second clamping member  316 . The retractor handle  320  can be reinserted into the opening  317  by reapplying manual force generally perpendicular to the axis of the retractor handle  320 . 
   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.