Field of the Invention
The present invention relates to surgical instruments, and in particular to surgical instruments useful in biopsy and laparoscopic procedures.
Background of the Invention
Cutting instruments such as scissors and punches, and certain forceps have precisely aligned jaws which pivot to each other to provide the desired function, which if misaligned, severely reduces the performance of the tool, and if severe enough, causes damage if not complete destruction of the tool. Frequently, such pivoted cutting or clamping elements are mounted at the end of an operating rod or shaft, distal from the operator handle. Typically, when the working surfaces are experiencing difficulty, the operator twists the instrument by applying additional force to the cutting or clamping jaws via the handle, and also applies a torsion along the axis of the handle which is applied to the cutting or clamping jaws via the pivot point of the jaws. Moreover, when the jaws become misaligned through normal use, such misalignment often results in the instrument self-destructing.
The primary response of instrumentation manufacturers to minimize the problem of tip misalignment is to increase the relative size of the pivot points, which results in only a limited improvement in maintaining jaw tip alignment as the instrument is rotated or otherwise abused by the operator.
Moreover, cutting instruments such as scissors and punches typically have a continuous cutting surface to engage the tissue. The continuous cutting surface must be precisely aligned to provide optimal cutting, and further increases the necessity of the aforementioned tip alignment to provide optimal, if not useful instrument operation.
Furthermore, the amount of tissue which is excised by the cutting tool, or grasped by the jaws is largely determined by the effectiveness of the tip or most distal end of the cutting surfaces to engage the tissue, which is typically continuous with the adjacent perimeter portions of the jaw. However, the effectiveness of the continuous tip to engage the tissue is severely limited, and is further reduced as the tip becomes dull through use or misalignment.
Summary of the Invention
The surgical instrument according to the present invention provides confronting and sliding surfaces forward or distal of the pivot point, to provide an anti-racking cutting or clamping tool which maintains the tool tips in alignment despite shear forces applied to the tips by a translated rotational force applied to the instrument along the axis perpendicular to the pivot, as may be provided through operator abuse.
Furthermore, the present invention comprises complimentary asymmetrical or symmetrical bifurcated cutting jaws which are self aligning and reduce the requirement of precise hinge or pivot tolerance and alignment. The combined cutting surface formed by the mutual operation of the jaws is substantially continuous throughout the circumference of the cutting tool opening, while the cutting surface on each of the jaws is discontinuous.
Furthermore, tissue engagement via the tip of the jaws is significantly enhanced with the addition of protruding ends of the discontinuous cutting surfaces, which form an incisor-like cutting point to securely grasp the tissue in advance of the remaining jaw cutting surfaces as the jaws are moved together.
Brief Description of the Drawing
These and other features of the present invention will become more readily understood, or rendered obvious, upon a reading of the following detailed description, and upon an examination of the drawings, in which similar parts are identified by like reference numerals.
FIG. 1 is a side view of one embodiment of the present invention mounted on an elongated control arm;
FIG. 2A and FIG. 2B are embodiments of the present invention as affixed to the control arm, having one and two pivot points respectively;
FIG. 2C is an embodiment of the present invention having a sliding, non-pivoting jaw closure;
FIG. 3 is a plan view of the cutting surfaces of the jaws according to one embodiment of the present invention;
FIG. 3A-3D are plan views of the jaws according to alternate embodiments of the present invention;
FIG. 4A. 4B and 4C are pictorial representations of the cutting surfaces of the jaw according to the present invention from a frontal view;
FIGS. 5A, 5B, 5C are perspective drawings showing one embodiment of the present invention in the open, partially closed, and closed position; and
FIGS. 6A, 6B and 6C are partial side views of one embodiment of the present invention showing the relative engagement of the cutting surfaces for an open, partially closed, and closed relative position of the jaws.
Detailed Description of the Invention
The general configuration of surgical instrument 50 embodying the present invention wherein jaws 60A and 60B are connected to a control cable 70 having concentric operating members therein which are connected in turn to a control handle 75 including an outer concentric member 76 connected to the inner member of the control cable 70, and a handle inner member 78 connected to the control cable 70 external member, wherein the jaws 60A and 60B are closed with the movement of the control handle elements 76 and 78 together.
One and two pivot embodiments 80, 90 respectively, are shown in FIGS. 2A and 2B. The jaws 61A and 61B are moveable about a single pivot point 81 which is rigidly affixed to the outer member 72 of the control cable 70. As shown in FIG. 2B, in a two pivot embodiment, the pivot points 91 and 92 are rigidly affixed to the outer member 72 of the control cable 70. The jaw 62A is connected so as to pivot about point 91, and the jaw 62B is connected so as to pivot about point 92. The control cable inner member 71 is connected to the lever (proximal) ends of the jaws 62A and 62B. The jaws 61A and 61B are caused to move together as the center element 71 of the control cable 70 is withdrawn relative to the cable outer portion 72, which is connected to the proximal end of each jaw 61A and 61B. In the embodiment of the present invention having two pivot points 91 and 92 is shown in FIG. 2B, wherein the jaws 62A and 62B are moveable relative to each other when pivoted on pivot points 91 and 92 respectively. As the center portion 71 of the control cable 70 is withdrawn relative to the exterior member 72 of the control cable 70, the jaws 62A and 62B are moved towards each other.
A no-pivot embodiment 95 is provided in FIG. 2C, wherein jaws 67A, 67B are closed as center portion 71 of the cable 70 causes the arms 96A, 96B to be drawn against the end 97 of the exterior member of the control cable 70.
A plan view 100 of the confronting cutting surfaces of the jaws 63A and 63B according to one embodiment of the present invention is shown in FIG. 3. The jaw 63A includes a discontinuous cutting surface including portions 102A, 102B, 102C and 102D. The jaw 63B provides a complementary asymmetric jaw structure comprising a discontinuous cutting surface including portions 104A, 104B, 104C and 104D which mate in close proximity with the respective portions 102A, 102B, 102C and 102D when the taws 63A and 63B are moved towards one another about the pivot 110. In the embodiment shown in FIG. 3, the end surfaces 106A, 106B and 106C, as well as the cutting surface portions 102B and 102D of jaw 63A, are generally rounded downwardly into the plane of the drawing. Similarly, the end surfaces 108A, 108B and 108C, as well as the cutting surface portions 104A and 104C of jaw 63B, are generally rounded downwardly into the plane of the drawing. The end surfaces 114A, 114B and 114C, as well as the cutting surface portions 103A and 103C of jaw 63A, are raised upward and extend outward of the plane of the drawing. Similarly, the end surfaces 116A, 116B and 116C, as well as the cutting surface portions 105B and 105D of jaw 63B, are raised upward and extend outward out of the plane of the drawing. As a result of this construction, as the jaws 63A and 63B are pivoted towards one another on the pivot 110, the cutting surface 120A formed on the raised end surface 114A of jaw 63A, and the cutting surface 120B formed on the raised end surface 116A of jaw 63B, slide upon one another. In a similar manner, a pair of complementary slidable cutting surfaces 122A and 124A are provided by the ends of the cutting members 103A and 105D, respectively; and a pair of complementary slidable cutting surfaces 122B and 124B are provided by the ends of the cutting members 103C and 105B, respectively.
The cutting surfaces 102A and 102C are formed along the exterior edge of internal cutting members 103A and 103C; similarly, the cutting surfaces 104B and 104D are on the exterior edge of internal cutting members 105B and 105D of jaw 63B. The cutting surface 102B and 102D are formed on the interior edge of the exterior cutting member 103B and 103D of jaw 63A; similarly, the cutting surface 104A and 104C are formed on the interior edge of exterior cutting members 105A and 105C of jaw 63B. The jaws 63A and 63B are connected to lever arms 112A and 112B respectively and are relatively moveable about the pivot 110. The lever arms 112A and 112B each comprise a pair of lever arms spaced apart on said pivot to economically provide further structural integrity.
As can be seen in FIG. 3, internal cutting members 103A and 103C are laterally offset from exterior cutting members 103B and 103D. Cutting surfaces 102A, 102B, 102C and 102D, however, are substantially continuous when viewed from the position shown in FIG. 3 in that there is no lateral offset.
A plan view 100A of a jaw 163A according to an alternate embodiment is shown in FIG. 3A, including a greater number of cutting members 203A, 202B, 202C, 202D, 202E, 202F, 202G, 202H, 202I and 202J. A plan view 100B of a jaw according to a further embodiment is shown in FIG. 3B having parallel cutting members 204A, 204D and right-angled cutting members 204B, 204C.
Three simplified drawings 140A, 140B and 140C showing a partial cross section of one embodiment of the present invention in various stages of engagement of the jaws 64A and 64B is shown in FIGS. 4A, 4B, and 4C. As illustrated in FIGS. 4A-4C, the incisor-like protrusions 114A and 116A extend towards each other, presenting confronting and relatively slidable surfaces 120A and 120B. With the jaws 64A and 64B open in FIG. 4A, the tips of the protrusions 114A and 116A do not meet, and the cutting members 103A-103D and 105A-105D do not meet. As the jaws 64A and 64B are brought into a partially closed position as illustrated by FIG. 4B, the cutting member 103A and its complementary cutting member 105A, as well as the cutting member 103B and its complementary cutting member 105B, engage tissue (not shown). At the same time, the tips of the incisor-like protrusions 114A and 116A (see FIG. 4A) pierce the tissue, thus allowing the confronting surfaces 120A and 120B to slide relative to one another through the tissue.
As the jaws 64A and 64B are completely closed, as shown in FIG. 4C, the cutting surfaces discussed above are fully engaged as are the protrusions 114A and 116A and the sliding surfaces 122A, 124A and 122B, 124B (not numbered or illustrated in FIG. 4C for the sake of clarity, but indicated in FIG. 3).
Perspective drawings 150A, 150B and 150C showing an opened, partially closed and closed position of one embodiment of the present invention are shown in FIGS. 5A, 5B and 5C. As can be observed in FIGS. 5A-5C, the inner cutting members 103A and 105B are obscured by overlapping outer cutting members 105A and 103B when the jaws are in a completely closed position.
Simplified longitudinal cross sectional drawings 160A, 160B and 160C, showing one embodiment of the present invention in an open, partially closed, and closed position is shown in FIGS. 6A, 6B and 6C respectively. The anti-racking feature of the present invention can be appreciated by observing the sliding and overlapping motion of surfaces 122A and 124A of protrusions 114C and 116C respectively as the jaws 66A and 66B move from an open to a closed position, FIGS. 6A-6C. Thus according to the present invention as the cutting surfaces and the incisor-like protrusions 114A and 116A engage the tissue forward of the pivot 110, the intervening sliding surfaces 122A and 124A, as well as the surfaces 122B and 124B (not shown in FIGS. 6A, 6B and 6C, but indicated in FIG. 3 with respect to similar jaws 63A and 63B), engage, providing structural reinforcement of the jaws 66A and 66B allowing such to remain in precise alignment as the jaws are brought to a closed position.
The scope of the present invention includes further embodiments wherein the frontal portion of the jaws forward of dotted line 162 (distal from the pivot 110) is replaced with other surgical tip functions which require similar precise alignment, as may be applied to surgical procedures other than biopsy removal, such as laparoscopic surgery. Exemplary devices are shown in plan views 100C and 100D of FIG. 3C and FIG. 3D. The continuous edge 207 defines an enclosed volume 206, and ridges 208 form corrugated surfaces which grip tissue when each jaw mates with a complementary confronting jaw (not shown). Accordingly, the present invention includes the attachment of such surgical devices forward to provide a surgical instrument including the anti-racking structure having sliding surfaces 122A, 124A and 122B and 124B. Moreover, implementations embodying the dual pivot of FIG. 2B would provide the curved surfaces 122A, 124A and 122B, 124B having the appropriate curvature to mate and provide a transmission of force between as the jaws are brought to a full closed position. Further modifications and substitutions made by one of ordinary skill in the art is considered to be within the scope of the present invention, which is not to be limited except by the claims which follows: