Wide handle for true multi-fire surgical stapler

[0001] This application claims priority to U.S. Provisional Patent Application Ser. No. 61/209,692, filed on Mar. 9, 2009, which is herein incorporated by reference in its entirety.

[0002] The invention generally relates to surgical instruments, and more specifically to surgical staplers.

[0003] An endocutter is a surgical tool that staples and cuts tissue to transect that tissue while leaving the cut ends hemostatic. An endocutter is small enough in diameter for use in minimally invasive surgery, where access to a surgical site is obtained through a trocar, port, or small incision in the body. An exemplary endocutter, with true multi-fire capability, is the MICROCUTTER™ brand endocutter proposed by Cardica, Inc. of Redwood City. That device is described in, for example, U.S. patent application Ser. No. 11/851,379, filed on Sep. 6, 2007, published as U.S. Patent Application Publication No. 2009/0065552 on Mar. 12, 2009 (the “Endocutter Application”), which is herein incorporated by reference in its entirety. The MICROCUTTER™ brand endocutter achieves true multi-fire capability through staple-on-a-strip technology, where staples are frangibly fixed to a feeder belt and sheared from the feeder belt during deployment, after which the feeder belt is advanced to place another set of staples in firing position. Each feeder belt may be slid about a nose located distally within the staple holder, where the nose may be a curved surface or pulley. In this way, two sections of the feeder belt may be generally parallel to one another and spaced apart from one another substantially the same distance as the diameter of the nose, to facilitate motion of the feeder belt through the staple holder and/or through a shaft connected to the staple holder.

[0005] Referring to FIG. 1, a surgical stapler 2 may include a handle 4 and a shaft 6 attached to the distal end of the handle 4, or to any other suitable part of the handle 4. The handle 4 is advantageously at least partially hollow, defining a plenum 8 within, and the shaft 6 is advantageously tubular, with a lumen 10 defined therein. Alternately, the handle 4 and shaft 6 may be shaped in any other suitable manner. The surgical stapler 2 may also include an end effector that includes a staple holder and anvil, as set forth in the Endocutter Application.

[0006] A feeder belt 12 may be received within the handle 4 and/or the shaft 6, where staples 14 are frangibly connected to the feeder belt 12. The feeder belt 12 and staples 14 may be substantially as set forth in the Endocutter Application. The feeder belt 12 may extend from the plenum 8 within the handle 4 into the lumen 10 of the shaft 6, and from there into the staple holder. The feeder belt 12 may be a continuous loop that wraps around a nose in the staple holder, as described in the Endocutter Application, then extends back through the lumen 10 of the shaft 6 into the plenum 8 within the handle 4. Alternately, the feeder belt 12 need not be continuous, and may have two discrete ends that are not connected to one another. Where the feeder belt 12 extends in both directions through the lumen 10 of the shaft 6, the feeder belt 12 may be considered to have two segments 16, 18, where those segments 16, 18 may be spaced apart from one another in the lumen 10 of the shaft 6. Advantageously, the segments 16, 18 may be substantially parallel to one another within the lumen 10 of the shaft 6 along the length of the shaft 6. Alternately, the segments 16, 18 may be oriented differently with regard to one another along at least part of the length of the shaft 6. The segments 16, 18 are not specific, discrete sections of the feeder belt 12; the portions of the feeder belt 12 that may be considered the segments 16, 18 change as the feeder belt 12 is advanced, as described in greater detail below.

[0007] Within the plenum 8 in the handle 4, the segments 16, 18 may diverge, such that the segments 16, 18 are not parallel. A mandrel 20 may be positioned within the plenum 8 in the handle 4. such that the feeder belt 12 engages at least part of the surface 22 of the mandrel 20. In this way, at least part of the surface 22 of the mandrel 20 defines a path within the handle 4 along which the feeder belt 12 extends, and along which the feeder belt 12 is slidable. That is, the feeder belt 12 wraps around at least part of the surface 22 of the mandrel 20. The mandrel 20 may have any suitable shape. As one example, the proximal surface 24 of the mandrel 20 may be a convex curve. As another example, the mandrel 20 may also, or instead, include two surfaces 26, 28 that form a nonzero angle relative to one another. Those surfaces 26, 28 may be located distal to the proximal surface 24 of the mandrel, and those surfaces 26, 28 may form an acute angle relative to one another. Alternately, the surface 26, 28 may be nonparallel to one another in a different manner; for example, at least one surface 26, 28 may be curved. The surfaces 26, 28 may be spaced apart from one another, or may contact one another. Alternately, the surface 22 of the mandrel 20 may be configured in any other suitable manner. The mandrel 20 may be wider than the diameter of the shaft 6, such that the path along which the feeder belt 12 travels is wider than the diameter of the shaft 6. The mandrel 20 defines a nonlinear path along which the feeder belt 12 extends in order to allow the placement of more staples within the handle 4 than would be possible if the feeder belt 12 merely extended linearly within the handle, thereby allowing more actuations of the surgical stapler 2. Further, the mandrel 20 allows the feeder belt 12 to be a continuous loop, such that unfired staples on the feeder belt 12, prior to the first actuation of the surgical stapler 2, may extend proximally from the distal end of the shaft 6, along the nonlinear mandrel 20, then distally to the distal end of the shaft 6, maximizing the number of times the surgical stapler 2 can be actuated.

[0008] The surgical stapler 2 may be actuated substantially as set forth in the Endocutter Application, with the differences set forth herein. A plurality of staples 14 are deformed and then frangibly separated from the feeder belt 12, at the staple holder. The feeder belt 12 is then advanced through the lumen 10 of the shaft 6, to bring a new set of unfired staples 14 into the staple holder. As the feeder belt 12 is advanced, at least part of the feeder belt 12 slides or otherwise travels along a nonlinear path. For example, motion of the feeder belt 12 along the nonlinear surface 22 of the mandrel 20 results in advancement of the feeder belt 12 along a nonlinear path. The feeder belt 12 may be advanced such that the lower segment 18 of the feeder belt 12 moves proximally into the plenum 8 within the handle 4, moves away from the longitudinal centerline of the shaft 6 along a lower surface 28 of the mandrel 20, moves along the curved proximal surface 24 of the mandrel 20, then moves distally along an upper surface 26 of the mandrel 20 and distally into the lumen 10 of the shaft 6. Alternately, the feeder belt 12 may move in the opposite direction. In either direction, one segment of the feeder belt 12 moving proximally out of the lumen 10 of the shaft 6 moves away from the segment of the feeder belt 12 moving distally into the lumen 10 of the shaft 6. Further, in either direction, one segment of the feeder belt 12 moving distally into the lumen 10 of the shaft 6 moves toward the segment of the feeder belt 12 moving proximally out of the lumen 10 of the shaft 6. The staples 14 are oriented away from the mandrel 20 such that travel of the feeder belt 12 along the mandrel 20 does not deform the staples 14. Once the feeder belt 12 has moved such that fresh, unfired staples 14 are present in the staple holder, the surgical stapler 2 may be actuated again, without the need for replacement of a cartridge or disposable loading unit.

[0009] While the invention has been described in detail, it will be apparent to one skilled in the art that various changes and modifications can be made and equivalents employed, without departing from the present invention. It is to be understood that the invention is not limited to the details of construction, the arrangements of components, and/or the method set forth in the above description or illustrated in the drawings. Statements in the abstract of this document, and any summary statements in this document, are merely exemplary; they are not, and cannot be interpreted as, limiting the scope of the claims. Further, the figures are merely exemplary and not limiting. Topical headings and subheadings are for the convenience of the reader only. They should not and cannot be construed to have any substantive significance, meaning or interpretation, and should not and cannot be deemed to indicate that all of the information relating to any particular topic is to be found under or limited to any particular heading or subheading. Therefore, the invention is not to be restricted or limited except in accordance with the following claims and their legal equivalents.