Abstract:
A surgical clamp 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 is positionable between a first position with the first and second clamping members being in a nonclamping position and a second position with the first and second clamping members being in a clamping position wherein the first and second sockets constrict to retain the first and second surgical rods in selected positions.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority of U.S. Provisional Application No. 60/535,910, filed on Jan. 12, 2004, the content of which is hereby incorporated by reference in its entirety.  
         [0002]     This application is also a continuation-in-part of application Ser. No. 10/732,491 filed on Dec. 10, 2003, the content of which is hereby incorporated by reference in its entirety, which is a continuation of application Ser. No. 10/664,195, filed Sep. 17, 2003, the contents of which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION  
       [0003]     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 threaded actuating mechanism flexing a fulcrum portion.  
         [0004]     Prior to performing a surgical procedure requiring retraction, a retractor support apparatus is typically positioned about the surgical site. Retractor clamps are commonly used to mount the retractor support apparatus with respect to an operating table, as well as to attach surgical retractors to the retractor support apparatus.  
         [0005]     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.  
         [0006]     However, the use U-shaped clamping structures may be cumbersome in certain surgical procedures. First, the U-shaped clamping structure must be positioned 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, an end of the retractor handle must be positioned through the other U-shaped clamps prior to positioning the retractor in the retracting position.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention includes a clamp for clamping two elongated members where each elongated member has a central axis. The clamp includes at least two clamping members both of which have clamping sockets with an opening for accepting an elongated member in a generally orthogonal direction to the axis of the member. The clamp also includes a mechanism that constricts the opening of the clamping socket of both members generally simultaneously such that the respective elongated member is captivated within each clamping socket.  
         [0008]     The present invention also includes a surgical clamp having a clamping portion with first and second legs that are spaced apart and extend from different sides of the clamping portion. A shaft extends through the first and second legs and has an actuating mechanism threadably engaging the shaft between the first and second legs. The actuating mechanism is movable to force the first and second legs to move in opposing directions thereby placing the clamping portion into a clamping position.  
         [0009]     The present invention also includes a surgical clamp 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 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 is positionable between a first position with the first and second clamping members being in a nonclamping position and a second position with the first and second clamping members being in a clamping position wherein the first and second sockets constrict to retain the first and second surgical rods in selected positions. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is a perspective view of the surgical clamp of the present invention in a non-clamping position.  
         [0011]      FIG. 2  is another perspective view of the surgical clamp of the present invention in a non-clamping position.  
         [0012]      FIG. 3  is an exploded view of the surgical clamp of the present invention.  
         [0013]      FIG. 4  is a sectional view of the surgical clamp of the present invention in a clamping position. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0014]     The present invention includes a low-profile surgical clamp generally illustrated at  FIG. 1  at  10 . The clamp is particularly suited for mounting a retractor (not shown) with respect to an operating table (not shown). The clamp  10  includes a bottom clamping member  12  having a support arm clamping surface  14  proximate a clamping end or portion  24  and a top clamping member  16  having a retractor clamping surface  18 . Other components may be substituted for the top clamping member  16  such as, but not limited to, permanently attached retractors, or retractors that are attached using other types of clamps or fasteners.  
         [0015]     Referring to  FIGS. 2-4 , the bottom clamping member  12  is positioned on a retractor support arm  11  by positioning the support arm clamping surface  14  that defines a support arm clamping socket  38  proximate the retractor support arm  11 . Manual force is placed upon the bottom clamping member  12  and the support arm  11  such that a constricted entrance  39  to support arm clamping socket  38  opens and the support arm  11  is forced into the clamping socket  38 .  
         [0016]     Referring to  FIGS. 1-4 , when the clamp  10  is in the non-clamping position, the bottom clamping member  12  is retained on the retractor support arm  11  by the constricted entrance  39  to the support arm clamping socket  38 . In an exemplary embodiment, a bead or raised surface  40  is disposed along lengths of resilient portions  45 ,  37  where the bead or raised surface  40  constricts the entrance  39 . However, other devices that constrict the entrance  39  to the first clamping socket  38  are within the scope of the present invention including, but not limited to, a clip, a roller or a spring-loaded device. As manual force is placed upon the bottom clamping member  12  and the support arm  11 , the resilient portions  45 ,  47  move to open the entrance  39  to the support arm clamping socket  38  thereby allowing the support arm  11  to be positioned within the support arm clamping socket  38 .  
         [0017]     The constricted entrance  39  provides a preliminary clamping force around the portion of the retractor support arm  11  such that the bottom clamping member  12  does not slip off of the support arm  11  when the clamp  10  is in the non-clamping position. The entrance  39  of the support arm clamping socket  38  should not be so constricted to prevent use of manual force positioned in the bottom clamping member  12  about the portion of the retractor support arm  11 . However, the entrance  39  of the support arm clamping socket  38  should be sufficiently constricted to prevent the bottom clamping member  12  from accidentally slipping off of the retractor support arm  11 . An exemplary amount of constriction of the entrance  39  of the support arm clamping socket  38  is between about 0.010 inches and 0.020 inches and preferably about 0.015 inches.  
         [0018]     The support arm clamping socket  38  permits the bottom clamping member  12  to be placed on the retractor support arm  11  without moving any other surgical equipment having been previously positioned on the retractor support arm  11 . By socket is meant an opening or a cavity into which an inserted part such as a retractor support apparatus, is designed to fit and wherein the retractor support apparatus can be inserted into the socket from an infinite number of directions in a 180 degree range starting from a substantially parallel position to a 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. By opening is meant an entrance to the clamping socket from an external surface of the clamping member into which a portion of a part such as the retractor support apparatus is inserted in a direction that is not parallel to a central axis of the part where the opening may be constricted or non-constricted. Preferably the part is inserted through the opening and into the clamping socket in a direction substantially perpendicular to the central axis of the part, although other directions are within the scope of the present invention.  
         [0019]     Referring to  FIGS. 2-4 , the support arm clamping surface  14  is configured to generally conform to the cross sectional configuration of the retractor support arm  11 , but may be configured to other shaped cross sections. In a preferred embodiment, the support arm clamping surface  14  conforms to a substantially circular cross sectional configuration of the retractor support arm  11 .  
         [0020]     The bottom clamping member  12  is preferably of a unitary construction and includes a fulcrum portion  28  between the clamping end  24  and an attachment end  26 . The fulcrum portion  28  extends between an upper leg portion  32  and a lower leg portion  34 , which define a recess  30  proximate the attachment end  26 . As the upper and lower leg portions  32 ,  34  are spread apart, the fulcrum portion  28  flexes resulting in a contraction of the support arm clamping socket  38 . The contracted support arm clamping socket  38  creates a frictional engagement between the support arm  11  and the support arm clamping surface  14 .  
         [0021]     The upper and lower leg portions  32 ,  34  are spread apart with an actuating mechanism  80  positioned within the recess  30 . Referring to  FIGS. 3 and 4 , the actuating mechanism  80  preferably includes a threaded bore  84  which engages a threaded region  102  of a shaft  100  that is non-rotatably positioned within the recess  30  between the upper and lower leg portions  32  and  34 .  
         [0022]     Referring to  FIGS. 1-4 , the actuating mechanism  80  rotates and travels down the threaded region  102  such that the actuating mechanism  80  engages the bottom leg portion  34 . Further rotation of the actuating mechanism  80  forces the shaft  100  toward the upper leg portion  32 . As the shaft  100  is forced upward, a shoulder  113  on the shaft engages a proximal end  52  of the top clamping member  16 .  
         [0023]     As the shoulder  113  engages the proximal end  52 , the top clamping member  16  is fixed in a selected rotational position by a frictional engagement with the upper leg portion  32  of the bottom clamping member  12 . The force from the shoulder  113  causes a frusto-conical surface  50  of the top clamping member  16  to frictionally engage a frusto-conical surface  49  defining a through bore  48  in the upper leg portion  32  and thereby prevents rotation of the top clamping member  16 . When the actuating mechanism  80  is positioned in the non-clamping position, the top clamping member  16  rotates within the through bore  48  and is captivated to the upper leg portion  16  with a snap ring  58  positioned within an annular groove  56  about a perimeter of the top clamping member  16 .  
         [0024]     A retractor handle  20  is manually forced within a retractor clamping socket  17  defined by the retractor clamping surface  18  positioned on a distal end portion  54  of the top clamping member  16  with manual force. An arcuate upper portion  62  of the retractor clamping surface  18  and an end  102  of the shaft  100  positioned through a through bore  72  constrict an entrance  19  of the retractor clamping socket  17 . The through bore  72  extends through the top clamping member  16  along an axis  73  and intersects a bottom portion  61  of the retractor clamping surface  18  as best illustrated in  FIGS. 3 and 4 .  
         [0025]     The end  102  of the shaft is biased into the retractor clamping socket  17  with a compression spring  109  positioned about the shaft  100  and between the actuating mechanism  80  and the lower leg portion  34 . Manual force on the retractor handle  20  forces the end  102  of the shaft  100  from the retractor clamping socket  17  by compressing the compression spring  109  into a recess  85  in the actuating mechanism  80  which allows the retractor handle  20  to be positioned therein. With the retractor handle  20  positioned within the retractor clamping socket  17 , the compression spring  109  biases the end  102  of the shaft  100  back into the retractor clamping socket  17  and thereby slidably retains the retractor handle  20  therein.  
         [0026]     Alternatively, the shaft  100  may threadably engage a threaded through bore  42  in the lower leg portion  34 . A handle  22  may be fixedly attached to the shaft  100  to rotate the shaft  100  into the clamping position from the non-clamping position. Because the shaft  100  does not move or float along the axis  73 , when the clamp  10  is in the non-clamping position the end  102  of the shaft  100  is positioned away from the retractor clamping socket  17 . When the shaft  100  is rotated into the clamping position, the end  102  of the shaft  100  is forced into the retractor clamping socket to frictionally retain the retractor handle  20  therein.  
         [0027]     Although the top clamping member  16  is described and illustrated in the drawings as retaining and clamping a retractor handle  20 , the top 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.  
         [0028]     Prior to using the clamp  10 , a position of the shaft  100  within the clamp  10  is adjusted with a screwdriver engaging a slot  111  such that the top and bottom clamps  16 ,  12 , respectively, are in a non-clamping position when the actuating mechanism  80  is in a non-clamping position and the top and bottom clamps  16 ,  12 , respectively, are in a clamping position when the actuating mechanism  80  is in the clamping position. The threaded engagement of the threaded region  112  with the threaded bore  84  adjusts the position of the shaft  100  with respect to the actuating mechanism  80  such that the clamp  10  functions properly.  
         [0029]     With the shaft  100  in the selected positioned within the clamp  10 , a cap  116  is fixedly attached to the shaft  100 , preferably with a weld. The cap  116  has substantially flat, parallel sides  112 ,  114  that cooperate with substantially flat parallel sides  44 ,  46 , respectively, of an elongated slot  42  in the lower leg portion  34 . The engagement of the sides  112 ,  114  of the cap  116  with the sides  44 ,  46  of the elongated slot  42  prevent rotation of the shaft  100  within the clamp  10  while allowing the shaft  100  to move along the axis  73  with respect to the bottom and top clamping members  12 ,  16 .  
         [0030]     A washer  98 , although not necessary to practice the present invention, is positioned between the actuating mechanism  80  and the lower leg portion  34  to prevent either a actuating mechanism  80  or the lower leg portion  34  from wearing over time with use. The washer  98  is preferably made of a wear resistant polymer such as PEEK.  
         [0031]     The top clamping member  16  is positioned into a clamping position at approximately the same time that the actuating mechanism  80  forces the upper and lower leg portions  32 ,  34  apart by positioning the actuating mechanism  80  into the second clamping position. To position the actuating mechanism  80  into the second clamping position, a handle  22  fixedly attached to the actuating mechanism  80  is moved in a direction of arrows  23 , as illustrated in  FIG. 1 , which rotates the actuating mechanism  80  about an shaft  100  and the axis  73 . A pitch of threads of the threaded region  102  of the shaft  100  and the threads within the bore  84  of the actuating mechanism  80  are designed such that as the actuating mechanism  80  is rotated about 180 degrees, the clamp  10  is positioned from the first non-clamping position to the second clamping position.  
         [0032]     As the actuating mechanism  80  is rotated, the bore  84  threadably engages the threaded region  102  of the shaft  100  and forces the actuating mechanism  80  towards the lower leg portion  34 . As the actuating mechanism  80  is forced into the lower leg portion  34 , and a force is placed upon the lower leg portion  34 , the actuating mechanism  80  and the shaft  100 . A maximum force is placed upon the lower leg  34 , the actuating mechanism  80  and the shaft  100  when the actuating mechanism  80  is rotated approximately 180 degrees opposite the non-clamping position where an extension  81  from the actuating mechanism  80  contacts a surface  29  defining an inner region of the recess  30  as best illustrated in  FIGS. 2 and 3 .  
         [0033]     Referring to  FIG. 4 , with the actuating mechanism  80  in the second position, the compression spring  109  is compressed within the recess  85  and the actuating mechanism  80  transfers the force to the lower leg portion  34 . The end  102  of the shaft  100  is forced into the retractor clamping socket  17  of the top clamping member  16  and frictionally secures the retractor handle  20  within the retractor clamping socket  17  between the end  102  of the shaft  100  and the arcuate upper portion  62 .  
         [0034]     Further, with the actuating mechanism  80  in the second position, the shoulder  113  of the shaft  100  is forced into the proximal end  52  of the top clamping member  16  thereby causing a frictional engagement between the frusto-conical surfaces  49 ,  50  of the top clamping member  16  and the upper leg portion  32 . The frictional engagement of the frusto-conical surfaces  49 ,  50  secures the top clamping member  16  in a selected position with respect to the bottom clamping member  12 .  
         [0035]     Further, with the actuating mechanism  80  in the second position, the distance between the shoulder  113  and a bottom surface  96  of the actuating mechanism  80  is greater than the distance between the washer  98  and the upper leg portion  32  such that the upper and lower leg portions  32 ,  34  are forced apart thereby transferring the force to the upper leg portion  32  from the shaft  100 . One skilled in the art will recognize that the pitch of threads on the threaded region  102  and the threaded bore  84  can be adapted to increase or decrease the distance of travel of the actuating mechanism  80  on the shaft  100  as is necessary to place the clamp  10  into the clamping position.  
         [0036]     With the upper and lower leg portions  32 ,  34  forced apart, the fulcrum portion  28  flexes which causes the support arm clamping socket  38  to constrict such that the support arm clamping surface  14  frictionally engages the retractor support arm  11 .  
         [0037]     Referring to  FIG. 3 , an upper surface  97  of the actuating mechanism  80  includes an indention  86  which engages a pin  88  extending from the upper leg portion  34  and into the recess  30  when the actuating mechanism  80  is in a non-clamping position. The engagement of the pin  88  with the indention  86  retains the actuating mechanism  80  in the first non-clamping position such that the bottom and top clamping members  12 ,  16  are in non-clamping positions.  
         [0038]     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  FIG. 1 . Therefore, the operator can conveniently manipulate the actuating mechanism  80  from the first non-clamping position to the second clamping position by gripping the handle  22  and the retractor support arm  11  with one hand and forcing the handle  22  towards the retractor support arm  11 .  
         [0039]     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 top clamping member  16  and the handle  22  are disposed proximate the retractor support arm  11 . By disposing the top clamping member  16  and the handle  22  proximate the retractor support arm  11 , a surgical site remains relatively open and free of obstruction thereby providing better access to the surgical site.  
         [0040]     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 actuating mechanism  80  into the first non-clamping position such that the support arm clamping socket  38  is not constricted. The bottom clamping member  12  is then detached from the retractor support arm  11  with manual force in an opposite direction as used to position the bottom clamping member  12  on the retractor 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 the entrance  39  to the support arm clamping socket  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 .  
         [0041]     The retractor handle  20  can also be repositioned within the top 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 top clamping member  16  by providing manual force in the opposite direction of the force used to position the retractor handle  20  within the retractor clamping socket  17 . The retractor handle  20  can be reinserted into the retractor clamping socket  17  by reapplying manual force generally perpendicular to the axis of the retractor handle  20 .  
         [0042]     The surgical clamp  10  of the present invention having the support arm clamping surface  14  and the retractor clamping surface  18  enables the clamp  10  to be positioned upon the retractor support arm  11  in a selected position. Further, an additional retractor  20  can be easily and conveniently positioned within a surgical site without having to position the end of the retractor through the retractor clamping socket  17  defined by the retractor 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.  
         [0043]     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.