Patent Abstract:
A surgical clamp for occluding a body conduit includes first and second jaws moveable relative to each other in a generally parallel relationship. A handle assembly is operable to move the jaws relative to each other between a space position and proximate position. The first jaw has an elongate configuration characterized by a length and a width. First portions of the first jaw have in cross section a first shape which remains generally constant in area along the first jaw, while second portions have in cross section a second shape which varies in area along the length of the first jaw. The resulting clamp has a low profile jaw design which dimensional-shaped cross section which provide increased stiffness and reduced flexibility.

Full Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     This invention relates generally to surgical clamps, and more specifically to blood vessel occlusion clamps.  
         [0003]     2. Discussion of the Prior Art  
         [0004]     Surgical occlusion clamps are commonly used to close off or occlude body conduits, such as blood vessels. A common variety of vessel occlusion clamp is that referred to as a “Bahnson” clamp, which has small metal handles that operate a pair of opposing jaws. When the jaws are brought into close proximity on either side of a vessel, the vessel is squeezed against itself to achieve at least partial occlusion. It is of particular importance that the jaws of the clamp be stable, and sufficiently inflexible that the jaws do not cross over or scissor, but rather press directly against each other along their length to occlude any conduit disposed between the jaws.  
         [0005]     It is also desirable to have a thin, low-profile jaw design that can access narrow areas. In the past, this desire for a low-profile design has worked against the need for stability in the jaws. Jaw inserts have been provided, but typically have had exposed edges, ends, and corners, which tend to entrap or entangle surgical sutures.  
       SUMMARY OF THE INVENTION  
       [0006]     In accordance with the present invention, a vessel occlusion clamp of the Bahnson type is provided with improved stability and reduced flexibility, while maintaining a low-profile jaw design. In a preferred embodiment of the clamp, the jaws are provided with a receding or tapered T-beam cross section, which greatly reduces the bendibility or flexibility of the jaws. Other dimensional-shaped cross sections of interest include a U-beam cross section, an I-beam cross section, a trapezoidal I-beam cross section, a continuous or whole-length T-beam cross section, a B-channel cross section, and an L-beam cross section. With the dimensional-shaped, cross section design, beam stiffness is substantially increased, while transverse deflection is greatly reduced. In addition, the transverse members forming the beam cross sections can be relied on to provide shielding of the jaw insert edges. This shielding prevents entrapment or entanglement of surgical sutures. Scallops or hollowed recesses can be provided in the jaws to facilitate installation and removal of the inserts without degrading structural jaw stability.  
         [0007]     In one aspect of the invention a surgical clamp is adapted for use in occluding a body conduit. The clamp includes a first jaw, and a second jaw movable relative to the first jaw in a generally parallel relationship. A handle assembly is operable to move the first and second jaws relative to each other between a spaced position and a proximate position. The first jaw has an elongate configuration characterized by a length and a width. First portions of the first jaw have in radial cross section a first shape which remains generally constant in area along the length of the first jaw. Second portions of the first jaw have in cross section a second shape which changes in area along the length of the first jaw. The first portions will typically have a first width while the second portions will have a second width greater than the first width. An insert is adapted to be removably mounted on the first portions with the second portions extending laterally of the insert.  
         [0008]     In a further aspect of the invention, the surgical clamp includes a handle assembly and a pair of opposing jaws movable by the handle assembly in a plane of operation between a spaced orientation, wherein the jaws are spread to recede the body conduit, and a proximal orientation wherein the jaws are substantially closed to occlude the body conduit. At least one of the jaws has in cross section a non-rectangular configuration. An insert having a first width is carried by first portions of the jaw which have a second width. Second portions of the jaw have a third width which defines with the first portions the thickness of the jaw. The first width of the insert is less than the third width of the second portions and greater than the second width of the first portions.  
         [0009]     These and other features and advantageous of the invention will be better understood with a description of preferred embodiments and reference to the associated drawings. 
     
    
     DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is a front side perspective view of a vessel occlusion clamp of the Bahnson type, illustrating disposable inserts mounted on parallel jaws having a dimensional-shaped, cross section design;  
         [0011]      FIG. 2  is a perspective view similar to  FIG. 1 , showing the jaws with the disposable inserts removed;  
         [0012]      FIG. 3  is a side-elevation view of a clamp jaw illustrating a tapered, T-beam cross section;  
         [0013]      FIG. 4  is a cross section view taken along lines A-A of  FIG. 3 ;  
         [0014]      FIG. 5  is a cross section view taken along lines B-B of  FIG. 3 ;  
         [0015]      FIG. 6  is a cross section view similar to  FIG. 5  and illustrating a trapezoidal I-beam cross section;  
         [0016]      FIG. 7  is a cross section view similar to  FIG. 5  and illustrating a U-channel cross section;  
         [0017]      FIG. 8  is a cross section view similar to  FIG. 5  and illustrating a V-beam cross section;  
         [0018]      FIG. 9  is a cross section view similar to  FIG. 5  and illustrating an I-beam cross section; and  
         [0019]      FIG. 10  is a cross section view similar to  FIG. 5  and illustrating an L-beam cross section.  
     
    
     DESCRIPTION OF PREFERRED EMBODIMENT  
       [0020]     A vascular occlusion clamp of the Bahnson type is illustrated in  FIG. 1  and designated generally by the referenced numeral  10 . The clamp  10  includes a pair of handles  12  and  14  with a ratchet lock  16 , which pivot on a fulcrum  18  to move jaws  21  and  23  in a generally parallel relationship. Disposable inserts  25  and  27  are removably mounted on the associated jaws  21 ,  23 . In  FIG. 2 , the inserts  25  and  27  have been removed in order to illustrate the dimensional-shaped design of the jaws  21  and  23 . From this view it can be seen that the jaws  21  and  23  extend along a Z axis but move generally along an X axis. The width of the jaws is measured along a Y axis. Thus the jaws having a length along the Z axis, a width along the Y axis, and a thickness along the X axis.  
         [0021]     This dimensional-shaped design is further illustrated in the side-elevation view of  FIG. 3  and the associated cross sectional views of  FIGS. 4 and 5 . The side elevation view of  FIG. 3  is drawn in the YZ plane while the cross sectional views of  FIGS. 4 and 5  are drawn in the XY plane. In all of the cross sectional views of  FIGS. 4-10 , a preferred disposition of the associated insert  25  is illustrated in dotted lines.  
         [0022]     In this embodiment, the jaw  21  has an engagement section  29  with a generally constant profile along its length. This engagement section  29  is intended to occupy a channel within the associated insert  25 . The jaw  21  also includes a support section  31  which, in cross section forms a T with the elongate section  29 . It is this support section  31  that provides this embodiment with its dimensional-shaped structure. In this case, the support section  31  tapers from a narrow width at the distal end of the jaw  21  to a maximum width near the proximal end of the jaw  21 . With this dimensional-shaped configuration, the cross section of the jaw  21  is provided with substantially increased beam stiffness along the X axis and reduced transverse deflection along the Y axis.  
         [0023]     The support section  31  can also be relied on to shield the edges, ends, and corners of the insert  25  that can entrap or entangle surgical sutures. With the shielding provided by these transverse elements, the edges, ends, and corners are not as prominent. While this prevents entrapment of surgical sutures, it can also make it more difficult to remove the inserts  25  and  27  for disposal. It is for this reason that the embodiment of  FIG. 3  is provided with scallops or hollow recesses  33  and  35 , which provide shallow access to a proximal edge of each insert. With these recesses  33  and  35  provided in proximity to counterbored pin recesses  37 ,  39  ( FIG. 2 ), the inserts  25  and  27  can be easily engaged and removed.  
         [0024]     Other dimensional-shaped cross sectional designs providing these advantages are illustrated in  FIGS. 6-10 . Each of these non-rectangular shaped cross sections provide increased beam stiffness and reduce transverse deflection, compared to the rectangular cross sections of prior designs.  
         [0025]     In the embodiment of  FIG. 6 , the jaw  21  has a trapezoidal I-beam shape characterized by an inner flange  41  joined to an outer flange  43  by a center flange  45 . In this case, the inner flange  41  and the center flange  45  formed the engagement section  29  which is disposed in the channel of the insert  25 . The outer flange  43  forms the support section  31  and maintains an abutting relationship with the insert  25 . This I-beam shape has a trapezoidal configuration in that the inner flange  41  has a width less than the outer flange  43 .  
         [0026]     In the embodiment of  FIG. 7 , the jaw  21  in cross section has a generally U-shaped configuration. A center flange  50  is supported by two side flanges  52  and  54  which extend to outwardly directed flanges  56  and  58  respectively. In this embodiment, the center flange  50  and side flanges  52  and  54  form the engagement section  29  while the outwardly directed flanges  56  and  58  form the support section  31 . As in previously embodiments, the engagement section  29  is received within a center channel of the insert  25  while the support section  31  is disposed in an abutting relationship with the insert  25 .  
         [0027]     The embodiment of  FIG. 8  includes a jaw  21  having in cross section a V-shaped configuration. This embodiment includes a top flange  61  supported by side flanges  63  and  65  which extend to outwardly directed flanges  67  and  69 , respectively. In this embodiment, the side flanges  63  and  65  are disposed at an acute angle with respect to the top flange  61  and are also disposed at an angle with respect to each other. The top flange  61  and side flanges  63  and  65  form the engagement section  29  and are adapted to be disposed within a channel of the insert  25 . The outwardly directed flanges  67  and  69  form the support section  31  and are disposed in an abutting relationship with the insert  25 .  
         [0028]     The embodiment of  FIG. 9  includes a jaw  21 , having in cross section an I-Beam shape similar to that of  FIG. 6 . Thus, the jaw  21  has a top flange  72 , joined to a bottom flange  74  by a center flange  76 . In this embodiment, the top flange  72  has the same width as the bottom flange  74 , but a greater thickness than the bottom flange  74 . Also, the flanges  72 ,  74  and  76  are all disposed within the channel of the insert  25 . Accordingly, these three flanges in the illustrated embodiment form the engagement section  29  of the jaw  21 .  
         [0029]     In the embodiment of  FIG. 10 , the jaw  21  in cross section has a U-shaped configuration. This embodiment is characterized by a bottom flange  81 , side flanges  83  and  85 , and a center flange  87 . The side flanges  83  and  85  are equally spaced from the bottom flange  87  and extend from a side of the bottom flange  81 , opposite to that of the center flange  87 . Outwardly directed flanges  89  and  91  extend from the bottom flange  81  outwardly of the side flanges  83  and  85 . In this embodiment, portions of the bottom flange  81  together with the side flanges  83  and  85  form the engagement section  29 . The remaining portions of the bottom flange  81  together with the outwardly directed flanges  89  and  91  and the bottom flange  87  form the support section  31 .  
         [0030]     The resulting clamp  10  maintains the desired low profile jaw design, while the dimensional-shaped cross sections provide increased stiffness and reduced flexibility. As a result, transverse deflection is substantially avoided. The dimensional-shaped cross section also provides shielding to prevent entanglement of surgical sutures, while the scalloped and hollowed recessed  33  and  35  facilitate removal of the inserts  25  and  27 .  
         [0031]     Many alterations and modifications can be made to the foregoing preferred embodiments without departing from the spirit and scope of the invention. Therefore it must be understood that the illustrated embodiments have been set forth only by way of example, and should not be taken as limiting the invention. For example, notwithstanding the fact that the claims set forth below recite certain elements and combinations, it must be expressly understood that the invention includes other combinations of fewer, more or different elements, which are not disclosed above even when not initially claimed in such combinations.  
         [0032]     In addition, the words used in this specification to describe the invention and its various embodiments are to be understood not only in the sense of their commonly defined meanings, but also in the sense of any special definitions used in this specification, which may extend beyond the scope of the commonly defined meanings. Thus if an element can be understood in the context of this specification as including more than one meaning, than its use in the claims must be understood as being generic to all possible meanings supported by the specification and by the word itself.  
         [0033]     The definitions of the words or elements of the following claims are, therefore, defined in the specification to include not only the combination of the elements which are literally set forth, but all equivalent structure, material or method steps for performing substantially the same function, in substantially the same way, to obtain substantially the same way to obtain substantially the same result. In this sense it is therefore contemplated that an equivalent substitution of two or more elements may be made for any one of the elements in the claims below or that a single element may be substituted for two or more elements in a claim.  
         [0034]     Insubstantial changes from the claimed subject matter, now known or later devised, are expressly contemplated as being equivalently within the scope of the claims. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are deemed to be within the scope of the defined elements.  
         [0035]     The claims are thus to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, what can be obviously substituted, and also what essentially incorporates the idea of the invention. Many alterations and modifications can be made to the foregoing preferred embodiments without departing from the spirit and scope of the invention. Therefore it must be understood that the illustrated embodiments have been set forth only by way of example, and should not be taken as limiting the invention. For example, notwithstanding the fact that the claims set forth below recite certain elements and combinations, it must be expressly understood that the invention includes other combinations of fewer, more or different elements, which are not disclosed above even when not initially claimed in such combinations.  
         [0036]     In addition, the words used in this specification to describe the invention and its various embodiments are to be understood not only in the sense of their commonly defined meanings, but also in the sense of any special definitions used in this specification, which may extend beyond the scope of the commonly defined meanings. Thus if an element can be understood in the context of this specification as including more than one meaning, than its use in the claims must be understood as being generic to all possible meanings supported by the specification and by the word itself.  
         [0037]     The definitions of the words or elements of the following claims are, therefore, defined in the specification to include not only the combination of the elements which are literally set forth, but all equivalent structure, material or method steps for performing substantially the same function, in substantially the same way, to obtain substantially the same way to obtain substantially the same result. In this sense it is therefore contemplated that an equivalent substitution of two or more elements may be made for any one of the elements in the claims below or that a single element may be substituted for two or more elements in a claim.  
         [0038]     Insubstantial changes from the claimed subject matter, now known or later devised, are expressly contemplated as being equivalently within the scope of the claims. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are deemed to be within the scope of the defined elements.  
         [0039]     The claims are thus to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, what can be obviously substituted, and also what essentially incorporates the idea of the invention.

Technology Classification (CPC): 0