Patent Publication Number: US-2023149006-A1

Title: Tricuspid Retractor Blade Assembly

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     In general, the present invention relates to blade retractors that are used during surgical procedures. More particularly, the present invention relates to surgical retractors having blades that can be selectively adjusted in orientation to meet the needs of a surgeon. 
     2. Prior Art Description 
     Surgical retractors are used to manipulate tissue during surgery. Simple retractors have a blade head at the end of an elongated handle that is typically used to push or pull tissue away from a targeted area. More complex retractors have blade heads that can be manipulated to either separate or compress tissue as the retractor is manipulated. Retractors can be made for general use or can be specifically designed for particular surgical procedures. For example, the Cosgrove™ mitral valve retractor sold by Kapp Surgical Instrument Inc., and the cardiac tissue retractor disclosed in U.S. Pat. Application Publication No. 2011/0046448 to Paolitto are both retractors that are specifically designed to move cardiac tissue during valve replacement surgery. 
     A problem associated with many prior art retractors is that they have blade heads that are cumbersome. As such, many prior art retractors are limited to use during invasive surgical procedures. However, in modern surgery, invasive surgical procedures are becoming less common. Rather, many traditionally invasive surgical procedures are being replaced with minimally invasive surgical procedures. In a minimally invasive surgical procedure, very small incisions are made into the body. Elongated instruments are then inserted into the small incisions to access the area within the body cavity needing surgery. The small incisions cause much less injury to the body than does an invasive surgical procedure. Accordingly, the patient typically recovers more rapidly from the surgery with less adverse side effects. 
     During some surgical procedures, such as heart valve surgery, a specialized retractor is needed to manipulate the heart muscle so that unobstructed access is provided to the surgical site. However, if the surgery is minimally invasive, traditional retractors cannot be brought into the surgery site. The surgeon is therefore limited to small retractors and probes that can be inserted through the small surgical incisions. These retractors are typically inadequate in their capabilities. Furthermore, the space available to manipulate the retractors is severely limited by the surgical incisions. As a result, a small retractor cannot always be manipulated into a position where it is of the most use to the surgeon. 
     In U.S. Pat. No. 8,460,185 to Epstein, a retractor system is disclosed that is intended for use during a minimally intrusive surgical procedure. However, the size of the blade head utilized on the retractor is directly proportional to the size of the incision that must be made in the body. This is because the blade head must be passed through the incision when entering the body. Accordingly, a surgeon must balance the size of the retractor against the size of the incision. 
     A need therefore exists for a specialized retractor having an expandable blade head that can be used in a minimally invasive surgical procedure. In this manner, the blade head can be inserted into the body through a small incision and then expanded into a larger size within the body. A need also exists for a retractor system, where a blade can be selectively configured into different shapes in order to better serve the needs of the surgeon. In this manner, one retractor system can be utilized in a large array of roles during a surgical procedure. These needs are met by the present invention as described and claimed below. 
     SUMMARY OF THE INVENTION 
     The present invention is a retractor with a specialized blade head assembly. The blade head assembly has a central plate. The central plate extends between a first side edge and a second side edge. A first rotatable arm is attached to the first side edge of the central plate with a first hinge joint. The first rotatable arm can be rotated about the first hinge joint through a first range of motion. A second rotatable arm is attached to the second side edge of the central plate with a second hinge joint. The second rotatable arm can be rotated about the second hinge joint through a second range of motion. Both the first hinge joint and the second hinge joint are friction hinges that require a threshold force to move. The threshold force is selectively adjustable. 
     An elongated shaft interconnects with the central plate at a pivot joint midway between the first side edge and the second side edge. The elongated shaft can be attached to the blade head assembly after the blade head assembly has been inserted into a patient’s body. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a better understanding of the present invention, reference is made to the following description of an exemplary embodiment thereof, considered in conjunction with the accompanying drawings, in which: 
         FIG.  1    is a perspective view of an exemplary embodiment of a retractor; 
         FIG.  2    is perspective view of the blade head assembly with rotatable arms in an open configuration; 
         FIG.  3    is an exploded view of the blade head assembly shown in  FIG.  2   ; 
         FIG.  4    is a bottom view of the blade head assembly shown in an open configuration; and 
         FIG.  5    is a bottom view of the blade head assembly shown in a closed configuration. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     Although the present invention retractor can be embodied in different ways for different surgical procedures, the illustrations show only one configuration of a retractor that is particularly useful in a cardiac tricuspid valve surgery. This embodiment is selected in order to set forth one of the best modes contemplated for the invention. The illustrated embodiment, however, is merely exemplary and should not be considered a limitation when interpreting the scope of the appended claims. 
     Referring to  FIG.  1   , a retractor  10  is shown. The retractor  10  has a handle  12 , an elongated shaft  14 , and a blade head assembly  16 . The handle  12  is used by a surgeon to manipulate the blade head assembly  16  through an incision and into the body. The elongated shaft  14  has a first end  17  and an opposite second end  18 . The first end  17  of the elongated shaft  14  engages the blade head assembly  16 . The second end  18  of the elongated shaft  14  is coupled to the handle  12 . The elongated shaft  14  is illustrated as being straight and unistructural. However, it will be understood that the elongated shaft  14  can contain bends and/or joints that enable the shape of the elongated shaft  14  to better meet the needs of a surgeon during a particular procedure. 
     Referring to  FIG.  2    and  FIG.  3    in conjunction with  FIG.  1   , it can be seen that the blade head assembly  16  has a shaped central plate  20 . The central plate  20  has a front surface  21  and a back surface  23  that are defined between a top edge  22 , a bottom edge  24  and two side edges  26 ,  28 . The central plate  20  is curved, wherein the front surface  21  is concave and the back surface  23  is convex. The central plate  20  also contains a plurality of openings  30  that extend through the central plate  20 . The openings  30  enable blood, surgical rinse, and other liquids to flow through the central plate  20 . The openings  30  also enable a surgeon to view tissue through the central plate  20 . Lastly, the openings  30  reduce the weight and materials needed to manufacture the central plate  20  and the overall retractor  10 . 
     A joint recess  32  is formed in the middle of the central plate  20  adjacent to the bottom edge  24 . A hinge knuckle  34  is disposed in the joint recess  32 . The hinge knuckle  34  is locked in place by a base plate  36  that attaches to the bottom edge  24  of the central plate  20  with mechanical fasteners  38 . When locked in the joint recess  32 , the hinge knuckle  34  is free to rotate about a rotational axis  40  that is parallel to the side edges  26 ,  28  of the central plate  20  and perpendicular to the bottom edge  24 . A mounting hole  42  is formed through the hinge knuckle  34 . The mounting hole  42  receives and engages the first end  17  of the elongated shaft  14 . As such, it will be understood that when the elongated shaft  14  is engaged with the hinge knuckle  34 , the hinge knuckle  34  can rotate about its rotational axis  40 , and the orientation of the elongated shaft  14  relative the central plate  20  can be selectively adjusted throughout a range of movement. 
     The top edge  22  of the central plate  20  is bent toward the back surface  23  and terminates in a direction at or about ninety degrees from the rotational axis  40  of the hinge knuckle  34 . In addition to being curved, the top edge  22  of the central plate  20  contains scalloped protrusions  25  along its length. The scalloped protrusions  25  and the complex curvature of the top edge  22  form a surgical rake that is effective of engaging tissue while the retractor  10  is in use. 
     Hinge barrel sets  44 ,  46  are formed on the side edges  26 ,  28  of the central plate  20 . The first hinge barrel set  44  includes a first upper hinge barrel  48  and a first lower hinge barrel  49  that are spaced apart by a first gap  50 . Likewise, the second hinge barrel set  46  includes a second upper hinge barrel  52  and a second lower hinge barrel  53  that are spaced apart by a second gap  54 . Both the first lower hinge barrel  49  and the second lower hinge barrel  53  are internally threaded. Furthermore, both the first lower hinge barrel  49  and the second lower hinge barrel  53  contain limiting notches  55 ,  56 , the purpose for which are later described. 
     A first rotatable arm  58  and a second rotatable arm  60  are provided. The first and second rotatable arms  58 ,  60  are mirrored in size and shape. The first rotatable arm  58  has base  62 . A first knuckle cylinder  64  is affixed to the first rotatable arm  58 . The first knuckle cylinder  64  is sized and shaped to fit into the first gap  50  between the first upper hinge barrel  48  and the first lower hinge barrel  49  on the first side edge  26  of the central plate  20 . Likewise, the second rotatable arm  60  has base  66 . A second knuckle cylinder  68  is affixed to the second rotatable arm  60 . The second knuckle cylinder  68  is sized and shaped to fit into the second gap  54  between the second upper hinge  52  barrel and the second lower hinge barrel  53  on the second side edge  28  of the central plate  20 . 
     A first hook-shaped extension  70  extends from the first base  62  to complete the first rotatable arm  58 . The first hook-shaped extension  70  and the first base  62  define a first open central area  72 . A second hook-shaped extension  74  extends from the second base  66  to complete the second rotatable arm  60 . The second hook-shaped extension  74  and the second base  66  define a second open central area  76 . The hook shape enables the first rotatable arm  58  and the second rotatable arm  60  to not only displace tissue within the body, but hook around elongated features, such as arteries. 
     A first hinge pin  78  is used to join the first rotatable arm  58  to the central plate  20 . The first hinge pin  78  has a threaded head  80 , a threaded foot  82  and a smooth shaft  84  between the threaded head  80  and the threaded foot  82 . The threaded shaft  84  extends through the first lower hinge barrel  49 , the first knuckle cylinder  64  and the first upper hinge barrel  48 , therein forming a first hinge joint  86  between the first rotatable arm  58  and the central plate  20 . The threaded head  80  of the first hinge pin  78  threads into the first lower hinge barrel  49 . The threaded foot  82  of the first hinge pin  78  threads into a first end nut  88  beyond the first upper hinge barrel  48 . A first hinge cam  90  is provided. The hinge cam  90  engages the limiting notch  55  in the first lower hinge barrel  49 . This limits the rotational range of the first rotatable arm  58  about the first hinge joint  86 . 
     A second hinge pin  92  is used to join the second rotatable arm  60  to the central plate  20 . The second hinge pin  92  has a threaded head  94 , a threaded foot  96  and a smooth shaft  98  between the threaded head  94  and the threaded foot  96 . The shaft  98  extends through the second lower hinge barrel  53 , the second knuckle cylinder  68  and the second upper hinge barrel  52 , therein forming a second hinge joint  100  between the second rotatable arm  60  and the central plate  20 . The second hinge joint  100  is parallel to the first hinge joint  86 . The threaded head  94  of the second hinge pin  92  threads into the second lower hinge barrel  53 . The threaded foot  96  of the second hinge pin  92  threads into a second end nut  99  beyond the second upper hinge barrel  52 . A second hinge cam  102  is provided. The second hinge cam  102  engages the limiting notch  56  in the second lower hinge barrel  53 . This limits the ability of the second rotatable arm  60  to rotate about the second hinge joint  100 . 
     Referring to  FIG.  4    in conjunction with  FIG.  3   , it can be seen that the first rotatable arm  58  and the second rotatable arm  60  can be rotated about the first hinge joint  86  and the second hinge joint  100  respectively to fully open positions. In the fully open positions, it can be seen that the central plate  20 , the first rotatable arm  58  and the second rotatable arm  60  are all curved and share a common radius of curvature R 1 . The radius of curvature R 1  is equal to the width of the central plate  20  between the side edges  26 ,  28  of the central plate  20 , plus or minus twenty percent. 
     Referring to  FIG.  5    in conjunction with  FIG.  3   , it can be seen that the first rotatable arm  58  and the second rotatable arm  60  can be rotated about the first hinge joint  86  and the second hinge joint  100  respectively to fully folded positions. In the fully folded positions, the first rotatable arm  58  and the second rotatable arm  60  overlap. Furthermore, it should be noted that the first rotatable arm  58  and the second rotatable arm  60  do not contact the elongated shaft  14  as either the elongated shaft  14  or the rotatable arms  58 ,  60  move. 
     The first rotatable arm  58  and the second rotatable arm  60  can be selectively rotated about the first hinge joint  86  and the second hinge joint  100  to any positions between the fully open positions of  FIG.  4    and the fully closed positions of  FIG.  5   . The positions of the first rotatable arm  58  and the second rotatable arm  60  are set by the surgeon. The surgeon selects a configuration that he/she requires. The first hinge joint  86  and the second hinge joint  100  are both adjustable friction joints. That is, the force needed to rotate the first rotatable arm  58  about the first hinge joint  86  and to rotate the second rotatable arm  60  about the second hinge joint  100  can be selectively adjusted. The force needed to rotate the first rotatable arm  58  and/or the second rotatable arm  60  is adjusted by tightening and/or loosening the hinge pins  78 ,  92 . Likewise, by firmly tightening the hinge pins  78 ,  92 , the position of the first rotatable arm  58  and the position of the second rotatable arm  60  can be locked in place. As has been previously explained, the first hinge pin  78  has a threaded head  80  that engages the first lower hinge barrel  49 . By selectively tightening or loosening the first hinge pin  78 , the tension within the first hinge joint  86  can be altered. As tension forces increase, friction increases as does the force needed to alter the first hinge joint  86 . Likewise, the second hinge pin  92  has a threaded head  94  that engages the second lower hinge barrel  53 . By selectively tightening and loosening the second hinge pin  92 , the tension within the second hinge joint  100  can be altered. As tension forces increase, friction increases as does the force needed to alter the second hinge joint  100 . 
     Returning to  FIG.  1   , it will be understood that to use the present invention retractor  10 , a first incision is made in a body cavity. The blade head assembly  16  is then inserted into the body cavity through that the incision using any appropriately sized set of forceps. The blade head assembly  16  has a narrow cross section. As such, only a narrow incision needs to be made and the blade head assembly  16  can be advanced through the incision with minimal disruption to surrounding tissue. 
     Once the blade head assembly  16  is in place, another small incision is made into the body cavity. The elongated shaft  14  is then advanced through the second incision. Once in the body cavity, the elongated shaft  14  is connected to the blade head assembly  16 . Once the blade head assembly  16  is in place, the orientation of the central plate  20  and the two rotatable arms  58 ,  60  can then be altered to the needs of the surgeon. 
     It will be understood that the embodiment of the present invention that is illustrated and described is merely exemplary and that a person skilled in the art can make many variations to that embodiment. All such embodiments are intended to be included within the scope of the present invention as defined by the appended claims.