Abstract:
A retractor system of the present invention includes an adjustable arm, a carriage, and an activating device disposed in the carriage. The activating device causes movement of at least the adjustable arm to selectively stiffen or release the adjustable arm. The activating device further includes an engagement mechanism that causes movement of at least the carriage to selectively move the carriage. The present invention further includes a tubular retractor distally attached to the adjustable arm having a fiber optic cable embedded in the case of the tubular retractor that is capable of lighting the distal end of the tubular retractor when connected to a light source.

Description:
This application claims benefit of Provisional Appl. No. 60/102,788, filed Oct. 2, 1998. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention generally relates to a retractor system that is useful in surgical procedures. More specifically, the present invention relates to a surgical support structure, such as a retractor apparatus, and to a clamping mechanism for a retractor system. The present invention further relates to illuminating a retractor apparatus. 
     During many types of surgical procedures, such as micro endoscopic and direct division discectomy, it is customary to use a retractor. The retractor is used to hold back tissue proximate a surgical incision to enable a surgeon to work at and in the surgical incision. Retractors typically include a blade and an arm, such as a shaft, to which the blade is attached. The retractor is generally held in place by attachment to a retractor support apparatus that is positioned over a support surface, such as an operating table. The retractor support is usually attached to a side rail located along one or more sides of the operating table by a clamping device, such as a fulcrum clamp or a cammed clamp. 
     During surgical procedures, it is highly desirable that the retractor be flexible in order to precisely position the retractor. Quickly securing the retractor in the desired position is also equally important in promoting efficient and safe surgical procedures. Simple horizontal and vertical adjustment of the retractor at the clamping device positioned along the sides of the operating table are also key requirements for successful surgical procedures. 
     Current retractors are not easy to manipulate and position over the surgical incision since the arm is typically a solid inflexible rod. Locking mechanisms to lock the retractors in a precise location are typically cumbersome and require complex maneuvers that may increase the risk of injury to the patient. Horizontal and vertical adjustment of the retractor at the clamping device that attaches the retractor to the sides of the operating table still remains challenging since the clamping device may be difficult to operate, or be located at a place that may increase the risk of contamination to the patient. Thus, an urgent need presently exists to produce a retractor that overcomes these challenges. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention includes a retractor system having a clamp system that adjustably secures the retractor system to a support surface; and, an adjustable arm including a cam-activated device that selectively stiffens or releases the adjustable arm. The present invention further includes an engagement mechanism of the cam-activated device that causes movement of a carriage in which the engagement mechanism, and thus, the cam-activated device is disposed. The present invention further includes illuminating the retractor apparatus with a fiber optic cable embedded in a light carrying case surrounding a tubular retractor distally attached to the adjustable arm. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a surgical retractor apparatus of the present invention. 
     FIG. 2 is an exploded view of an adjustable arm and a cam-activated device of the present invention. 
     FIG. 3 is a top plan view of the adjustable arm and cam-activated locking device depicted in FIG.  2 . 
     FIG. 4 is a perspective view of the adjustable arm and the cam-activated locking device depicted in FIG.  3 . 
     FIG. 5 is a side plan view of the cam-activated locking device depicted in FIG.  3 . 
     FIG. 6 is a schematic view of a tubular retractor having a fiber optic cable that can be used in the present invention. 
     FIG. 7 is a schematic view of a dilator that can be used in the present invention. 
    
    
     DETAILED DESCRIPTION 
     A retractor system of the present invention is generally depicted at  10  in FIG.  1 . The retractor system  10  includes a clamping system  12  and a retractor apparatus  30 . The clamping system  12  includes a support clamp  14 , a clamp support rod  16 , a clamp knob  18 , a retractor clamp  20 , and a retractor support rod  22 . A suitable clamping system  12 , assigned to the same assignee as the present invention, is described in U.S. Pat. No. 5,400,772 and incorporated herein by reference. The clamping system  12  adjustably secures the retractor apparatus  30  to the clamp support rod  16  through retractor clamp  20 , as best depicted in FIG.  1 . The support clamp  14  clamps to a support surface, such as a rail  24  of an operating table (not shown). Turning the clamp knob  18  releases the support clamp  14  and allows the clamping system  12  to move in a horizontal direction along the rail  24 . Vertical adjustment of the clamping system  12  is accomplished by releasing the retractor clamp  20  and sliding the retractor clamp  20  adjustably secured to the retractor support rod  22  to a different vertical position. Horizontal adjustment of the retractor apparatus  30  occurs by releasing the retractor clamp  20  secured to the retractor support rod  22  and moving the retractor support rod  22  in direction  21  if desired. Releasing the retractor clamp  20  also permits the retractor apparatus  30  to freely rotate 360° if desired, as indicated by arrow  23 . 
     The retractor apparatus  30  includes a cam-activated device  32 , and an adjustable arm  40 , as illustrated in FIG.  1 . The cam-activated device  32  locks the adjustable arm  40  in a selected position. The cam-activated device  32  has a clamp support portion  34  and a distal end  36  as best depicted in FIG.  1 . The clamp support portion  34  has an aperture (not shown) to receive the retractor support rod  22  to attach the clamping system  12  to the retractor apparatus  30 . The distal end  36  receives a proximal end  42  of the adjustable arm  40 . 
     The adjustable arm  40 , as illustrated in FIGS. 1 and 2, is constructed of alternating cylinder(s)  46  and adjacent sphere(s)  48 , connected to each other by a cable  50  extending centrally therethrough. The cable  50  is housed in a bore  52  that extends through each cylinder  46  and adjacent sphere  48  as depicted in FIGS. 3 and 5. The alternating cylinder(s)  46  and adjacent sphere(s)  48  form the adjustable arm  40  that is highly flexible and is easy to manipulate in any direction by the surgeon. Preferably, each cylinder  46  and adjacent sphere  48  are integral with each other being machined from a single piece of metal. 
     Although alternating cylinders  46  and spheres  48  are used to practice the present invention, any pieced shape may be used to construct the adjustable arm  40 , such as barrels, buckets, or the like. Other forms of pieced shapes may be chosen based upon the need to impart more or less flexibility to the adjustable arm  40 . 
     The cam-activated device  32 , as best depicted in FIG. 2, includes a housing  70 , and a bore  76  that extends centrally through the housing  70 . The housing  70  has a proximal portion  72  and a distal portion  74 . Likewise, the centrally located bore  76  has a proximal end  78  and a distal end  80 . 
     A frustro-conical surface  54  integral to a cylindrical surface  56  extends above an externally threaded portion  60  of the adjustable arm  40  to form an annular shoulder  58 . An internally threaded section (not shown) at the distal end  80  of the bore  76  threadably engages the externally threaded portion  60  of the adjustable arm  40  to securely fix the adjustable arm  40  to the housing  70 . 
     The retractor apparatus  30  further includes a carriage  90  that engages a camming structure  100  for causing a camming action. The carriage is disposed within the proximal end  78  of the bore  76  and extends into a slot  71  of the housing  70 . The carriage  90  prevents the camming structure  100  from moving when disposed in slot  71 . 
     The carriage  90  has a groove  93  disposed on a distal end  92  for receiving the cable  50 . The cable  50  is attached to a spherical ball  98 , as illustrated in FIGS. 3 and 5. The spherical ball  98  is fixedly attached to a spherical groove  94  illustrated in FIG.  2 . The spherical groove has a surface conforming to the surface of the spherical ball  98 . Therefore, the spherical ball  98  attaches the cable  50  to the carriage  90  as best depicted in FIG.  5 . The groove  93  is substantially perpendicular to a cam slot  95  that has a lower semi-cylindrical surface  96  that engages the camming structure  100 . 
     The camming structure  100  has a cylindrical handle section  102  that includes a cam handle bore  104  for engaging a cam handle  106 , and two cylindrical sections  110  and  112  of equal diameter disposed on an axis  113 . The two cylindrical sections  110  and  112  are preferably oriented substantially perpendicular to the cam handle  106  as illustrated in FIG.  2 . The cylindrical section  112  is proximate to the cylindrical handle section  102 . The cylindrical sections  110  and  112  engages the cam slot  95  and prevents the cam structure  100  from moving independently of the carriage  90 . The cylindrical section  112  is proximate to the cylindrical handle section  102 . 
     The camming action is provided by a cam section  114  preferably at an intermediate location between the cylindrical sections  110  and  112 . The cam section  114  is smaller in diameter than the cylindrical section  110  and  112 . The cam section  114  has a cam axis  115  that is offset from the cylindrical axis  113 . When the cam handle  106  on the cylindrical handle section  102  is rotated about the axis  113 , the cam section  114  engages the cam slot  95  and thereby moves the carriage  90  in either direction A or in direction B, as best depicted in FIGS. 3,  4 , and  5 . When the carriage  90  is moved in either direction A or in direction B, the spherical ball  98  attached to the cable  50  is also moved in direction A or in direction B and thereby releases or stiffens the cable  50  in the adjustable arm  40 . 
     The camming structure  100  also engages the slot  71  in the housing  70 . The slot  71  has lower semi-cylindrical bottom surfaces  73  and  75  (not shown) that accepts cylindrical sections  110  and  112 , respectively. 
     A cap  130  fits into slot  71  of the housing  70 . The cap  130  secures the camming structure  100  in slot  71  while permitting the camming structure  100  to rotate about axis  113 . The cap  130  engages cylindrical sections  110  and  112  with arcuate downwardly facing surfaces  132  and  134 , respectively. When the cap  130  is positioned within slot  71 , apertures  136  and  138  are aligned with apertures  77  and  79 , respectively. Cap screws (not shown) are inserted into apertures  77  and  79  and extend into apertures  136  and  138  of the cap  130 . The cap  130  also prevents the camming structure  100  from moving upward and downward when disposed in slot  71 . 
     The housing  70  further includes coaxially disposed apertures  81 ,  83 ,  85  and  87 . Apertures  81  and  83  are located at the proximal portion  72  of the housing  70 . Apertures  85  and  87  are positioned at the distal portion  74  of the housing  70 . Apertures  81  and  85  are internally threaded (not shown) to accept set screws (not shown) that extend into the apertures  83  and  87  past the bore  76 . The set screws (not shown) that are threadably inserted into apertures  81 ,  83 ,  85  and  87  may be used to engage a mounting rail (not shown) to secure the retractor apparatus  30  to a support surface (not shown). 
     Set screws (not shown) that are threadably inserted into apertures  85  and  87  engage the externally threaded portion  60  of the adjustable arm  40 . The externally threaded portion  60  may be turned to decrease or increase the tension in the cable  50  with respect to the carriage  90 . This feature is important since the appropriate tension in the cable  50  must be maintained so that when the carriage  90  is moved in direction A or in direction B, the cylinders  46  and adjacent spheres  48  are selectively placed in a relaxed or locked position. The set screws (not shown) that are threadably inserted into apertures  85  and  87  engage the externally threaded portion  60  to lock the externally threaded portion  60  in a selected position in the housing  70  and at a selected distance from the carriage  90 . 
     In a preferred embodiment (not shown), a microscope is adjustably secured above the proximal end  202  of the tubular retractor  200  for use in surgical procedures, such as direct vision or micro endoscopic discectomy. The microscope has a light fixedly attached to the microscope for viewing a surgical incision under the microscope. The tubular retractor  200  with the microscope is positioned over the surgical incision and the light of the microscope illuminates the surgical incision by transmission of light through the distal end  204  of the tubular retractor  200 . Furthermore, the light from the microscope is transmitted along the entire circumference of the distal end  204  of the tubular retractor  200  and illuminates, without shadow formation, an entire portion of the surgical incision. 
     In another embodiment, the present invention further includes the use of a fiber optic cable  210  that carries light (not shown) from a source (not shown) and transmits the light to a distal end  204  of a tubular retractor  200  as illustrated in FIG.  6 . In the prior art, the fiber optic cable  210  was positioned within the tubular retractor  200 . The transmission of the light into the tubular retractor  200  provided light from a single point. When instrumentation was inserted into the tubular retractor  200  shadows would develop on a side of the instrument opposite of the light to distort the view for the surgeon. 
     The present embodiment eliminates this problem since the fiber optic cable  210  is positioned within a light carrying case  220  encasing the tubular, retractor  200 . The fiber optic cable  210  is positioned at least about one-half inch from the distal end  204 . When the fiber optic cable  210  is connected to a light source (not shown), light is transmitted through the light carrying case  220  through the distal end  204  and emitted along the entire circumference of the distal end  204 . Emission of light along the entire circumference of the distal end  204  eliminates shadows developing on any side of the instrument placed in the tubular retractor  200 . Eliminating the fiber optic cable  210  from within the tubular retractor  200  also maximizes working area for any instruments that are placed within the tubular retractor  200 . 
     By selectively extending the dilator  250  into the incision site, more precise positioning of the tubular retractor  200  can occur. 
     A set of dilators is used to separate muscle tissue and localize a site for the introduction of dilator retractor. 
     All though the present invention has been described with reference to preferred embodiments workers skilled in the art would recognize that changes maybe made in form and detail without departing from the spirit and scope of the invention.