US 20050085832 A1
A device is disclosed for introducing a flexible elongated element through at least two portions of a subject. In an embodiment, the device includes a proximal end and a distal end, as well as an advancement unit for longitudinally advancing the flexible elongated element toward the distal end such that a proximal end of the elongated element may pass from the distal end of said device with sufficient force to pass through the portions of the subject. The device also includes a securing unit for variably adjusting a securing force applied by the flexible elongated element to secure together the portions of the subject.
1. A device for fixing a flexible elongated element to a portion of a subject, said device comprising:
structure for retaining the flexible elongated element;
advancement means for longitudinally advancing the flexible elongated element from a proximal end of said device toward a distal end of said device with sufficient force to pass the element through the portion of the subject; and
securing means for securing the element to the subject and for variably adjusting a securing force applied by the flexible elongated element to the portion of the subject;
wherein said advancement means comprises a collect drive system.
This application is a continuation of U.S. application Ser. No. 09/496,305, filed Feb. 1, 2000, which claims the benefit of U.S. provisional application No. 60/118,039, filed Feb. 1, 1999. This application is also a continuation-in-part of U.S. application Ser. No. 10/014,991, filed Dec. 11, 2001, which is a continuation of U.S. application Ser. No. 09/368,273, filed Aug. 3, 1999 which claims the benefit of U.S. provisional application No. 60/118,039, filed Feb. 1, 1999 and U.S. provisional application No. 60/098,152, filed Aug. 27, 1998. Each of the above identified applications are hereby incorporated by reference in their entirety.
This invention relates to medical instruments and procedures in general, and more particularly to suturing instruments and methods for suturing.
Suturing instruments are typically used to draw together two or more portions of a subject patient (e.g., tissue such as muscle or skin) or to attach an object to the patient (e.g., to attach a piece of surgical mesh to the abdominal wall of the patient during hernia repair surgery).
Certain suturing instruments employ a needle that precedes a length of suture material through a subject.
For example, U.S. Pat. Nos. 3,470,875; 4,027,608; 4,747,358; 5,308,353; 5,674,230; 5,690,653; 5,759,188; and 5,766,186 generally disclose suturing instruments in which a needle, with trailing suture material, is passed through a subject.
U.S. Pat. Nos. 4,890,615; 4,935,027; 5,417,700; and 5,728,112 generally disclose suturing instruments in which suture material is passed through the end of a hollow needle after that needle has passed through a subject.
With all of the foregoing devices, a needle must be passed through the subject in order to deploy the suture. This is generally undesirable, since the needle typically leaves a larger hole in the subject than is necessary to accommodate only the suture material. In this respect it should be appreciated that it is generally desirable to alter each portion of the material being sutured as little as possible.
A suturing instrument has been devised which permits the suture material itself to pierce the subject without the use of a needle. However, this device does not permit sufficient flexibility with regard to the amount of tension that may be applied to the suture and tissue.
More particularly, U.S. Pat. No. 5,499,990 discloses a suturing instrument in which a 0.25 mm stainless steel suturing wire is advanced to the distal end of a suturing instrument, whereupon the distal end of the suturing wire is caused to travel in a spiral direction so as to effect stitches joining together two portions of a subject. After the spiral is formed, the beginning and end portions of the suture may be bent toward the tissue in order to inhibit retraction of the suture wire into the tissue upon removal of the suturing instrument. The stainless steel wire is sufficiently firm to hold this locking set. In addition, after the spiral is formed, the radius of the deployed suture spiral may then be decreased by advancing an outer tube over a portion of the distal end of the instrument. Again, the stainless steel wire is sufficiently firm to hold this reducing set.
Unfortunately, however, such a system does not permit sufficient flexibility in all situations with regard to the appropriate amount of tension to be applied to the subject, since the wire is relatively firm (i.e., firm enough to hold its sets). Such a system also does not provide sufficient flexibility with regard to the appropriate type of suture stitch to be applied, since the device is specifically configured to provide only a spiral suture stitch.
In contrast to the aforementioned limitations of the suturing instrument of U.S. Pat. No. 5,499,990, it is desirable that a suturing instrument approximate the portions of the material which is to be joined in the correct physiological relationship, and to urge the portions together with an appropriate amount of force. If too much force (or tension) is applied to the suture material, then the subject portions may become necrotic or the sutures may cut through the subject. If too little tension is applied to the suture material, then the healing process may be impaired.
U.S. Pat. No. 4,453,661 discloses a surgical instrument for applying staples. The staples are formed from the distal end of a length of wire. The distal end of the wire is passed through a subject, and thereafter contacts a die that causes the wire to bend, thereby forming the staple. The wire is sufficiently firm to take the set imposed by the die. The staple portion is then cut from the wire by a knife. Again, such a system suffers from the fact that it does not permit sufficient flexibility in all situations with regard to the appropriate tension to be applied to the subject, since the attachment is made by a staple which has a predefined geometry and is formed with relatively firm wire. In addition, the system is limited as to the type of fastening which may be applied, since the surgical instrument is limited to only applying wire staples.
There is a need, therefore, for a new suturing device that permits minimally disruptive suturing and permits flexibility in the placement, application, and tensioning of the suture material.
The invention provides a device for introducing a flexible elongated element through a subject. In one embodiment, the device includes a proximal end and a distal end, as well as an advancement unit for longitudinally advancing the flexible elongated element toward the distal end of the device such that a distal end of the flexible elongated element may pass from the distal end of the device with sufficient force to pass through the subject. The device also includes a securing unit for variably adjusting a securing force applied by the flexible elongated element so as to provide the desired securement to the subject.
In further embodiments, the device includes a guide tube for guiding the flexible elongated element through the device, toward the distal end of the device, as well as a rotation unit for rotating the distal end of the device so as to cause the flexible elongated element to wrap around itself, whereby to adjustably apply the securing force to the flexible elongated element.
These and other objects and features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiment of the invention, which is to be considered together with the accompanying drawings wherein like numbers refer to like parts, and further wherein:
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As will be discussed in further detail below, generally during use, suture wire (comprising wire formed of metal or any other suitable material having the required flexibility and stiffness) is drawn from a winding in wire supply cartridge 30 and is pushed through housing 12 and shaft 16 to end effector 18, which includes a pair of opposing jaw portions. The jaw portions may be brought together around the material which is to be sutured by actuating jaw closing actuator 22 when the jaw portions are positioned at an appropriate surgical location. The suture wire is driven through housing 12 and shaft 16 to end effector 18 by actuating wire advance button 20. The suture wire is driven from one jaw portion to the other jaw portion with sufficient force to penetrate the tissue placed between the jaw portions, and the suture wire is permitted to pass through the second jaw portion. The jaw portions are then permitted to separate and move away from the tissue, leaving the suture wire extending from the subject tissue to each of the two jaw portions. Shaft 16 and end effector 18 (together with wire supply cartridge 30) may then be rotated with respect to housing 12 and handle 14 by actuating either left-thumb-actuated rotation button 26 or right-thumb-actuated rotation button 28. This causes the portions of the suture wire that extend from the tissue to be twisted about one another so as to form a closed loop extending through the tissue. It will be appreciated that the size of this closed loop may be adjustably reduced by increasing the degree of twisting in the wire. The twisted loop of suture wire may then be cut off, at end effector 18, from the remaining portion of the suture wire that extends back through the suturing instrument. Such cutting may be effected by actuating wire cutting actuator 24.
As will be discussed in further detail below, wire supply cartridge 30 may be supplied separately from suturing instrument 10, with the wire supply cartridge 30 being loaded into suturing instrument 10 prior to commencing a suturing operation. As will also be discussed in further detail below, wire supply cartridge 30 may be disposable, such that the cartridge may be discarded after all of its wire has been used up.
As shown in
Batteries 34 supply a ground (or negative) potential to a ground connector post 36 (
Batteries 34 supply a positive potential to wire advance button 20, and to a first connector post 40, which in turn communicates with a first rotary electrical communicator 42. First rotary electrical communicator 42 permits electrical contact to be maintained with first connector post 40 when first rotary electrical communicator 42 is rotated with respect to first connector post 40. The positive potential from batteries 34 is also supplied (in parallel) to each thumb-activated rotation button 26, 28 (
First rotary electrical communicator 42 is in electrical communication with a wire advance motor 50 shown in
Second rotary electrical communicator 46 is in electrical communication with a shaft rotation motor 60 (
Jaw closing actuator 22 (
Wire cutting actuator 24 is coupled to a wire cutting linkage coupler 70 (
The wire supply cartridge 30 shown in
By way of example but not limitation, where suture wire 58 is formed out of stainless steel and has a diameter of 0.005 inch, wire guide 76 might have an inside diameter of 0.008 inch and an outside diameter of 0.016 inch. In addition, wire guide 76 is preferably formed out of polytetrafluoroethylene (PTFE) or some other relatively lubricious material. Alternatively, the interior of wire guide 76 may be coated with a lubricant so as to facilitate closely-supported, low-friction passage of the suture wire through the wire guide.
Further by way of example but not limitation, in one preferred form of the invention, suture wire 58 may comprise 316 LVM stainless steel having a tensile strength of 170 kpsi.
Although wire guide 76 extends through support unit 74 (
As shown in
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Pinion gear 62 (
End effector 18 (
Wire cutting linkage 72 (
It will be appreciated that the force of biasing spring 69 will normally keep cutting bar 104 in its distal position (i.e., with the cutting bar's opening 106 aligned with the fixed jaw portion's channel 108), unless and until wire cutting actuator 24 is activated so as to overcome the bias of spring 69.
In view of the foregoing construction, it will be seen that: (1) release lever 87 (
Suturing instrument 10 may be used to apply wire suture 58 to a subject so as to effect a desired suturing operation.
By way of example but not limitation, and looking now at
In any case, suturing instrument 10 is initially prepared for use by installing batteries 34 into handle 14, if batteries 34 are not already installed, and by installing wire supply cartridge 30 into the suturing instrument, if a cartridge 30 is not yet installed. As noted above, wire supply cartridge 30 is installed in suturing instrument 10 by (1) moving the drive barrel assembly's release lever 87 to its open position (
At this point suturing instrument 10 will be ready for use, with its movable jaw portion 98 being opened away from its fixed jaw portion 96, and with its cutting bar 104 being in its forward (
Next, suturing instrument 10 has its movable jaw portion 98 moved into engagement with its fixed jaw portion 96 (i.e., the jaws 96, 98 are placed in their “closed” position) by pulling jaw closing actuator 22 toward handle 14, and then the distal end of suturing instrument 10 is moved adjacent to subject portions 110, 112 (
In the case of a so-called closed surgical procedure, such positioning will generally involve moving the distal end of the suturing instrument through a cannula and into an interior body cavity; however, it is also envisioned that one might move the distal end of the suturing instrument directly into an otherwise-accessible body cavity, e.g., directly into the colon or esophagus, etc. In the case of a so-called open surgical procedure, such positioning might involve positioning the distal end of the suturing instrument adjacent to more readily accessible subject portions 110, 112.
In any case, once the distal end of suturing instrument 10 has been placed adjacent to subject portions 110, 112, jaw closing actuator 22 is released, such that biasing spring 69 (
Next, wire advance button 20 is activated so as to cause suture wire 58 to be driven forward, out of the distal end of wire guide 76, through the fixed jaw portion's channel 108, through opening 106 in cutting bar 104, through the fixed jaw portion's channel extension 108A, through subject portions 110, 112, and finally through an opening 113 (
Once this has been done, jaw closing actuator 22 is released so as to permit movable jaw portion 98 to return to its “open” position relative to fixed jaw portion 96, and then wire advance button 20 is used to pay out additional suture wire 58 as the distal end of suturing instrument 10 is stepped back (e.g., by about a centimeter or so) from subject portions 110, 112 (
Then jaw closing actuator 22 is used to move jaw portion 98 back into engagement with fixed jaw portion 96 once more (
Next, left-thumb-actuated rotation button 26, or right-thumb-actuated rotation button 28, is used to rotate shaft 16 and hence end effector 18. This causes suture wire 58 to twist on itself, initially creating a relatively large loop 116 (
Once suture wire 58 has been tightened to the desired degree, rotation of shaft 16 and end effector 18 is stopped, i.e., by releasing button 26 or button 28. Then wire cutting actuator 24 is depressed (e.g., it is pulled back toward handle 14) so as to pull cutting bar 104 proximally and thereby sever the suture wire 58 as the suture wire emerges from the fixed jaw portion's channel 108 and enters the cutting bar's opening 106 (
Then wire cutting actuator 24 is released, allowing biasing spring 69 to return cutting bar 104 to return to its distal position, and then jaw closing actuator 22 is released, allowing movable jaw portion 98 to move away from fixed jaw portion 96. Suturing instrument 10 may then be removed from subject portions 110, 112, which action will pull wire length 58A from movable jaw portion 98 (
The deployed suture wire 58 may then be pressed down flat against subject portions 110, 112, or rounded into a ball, or otherwise operated upon, so as to reduce the profile of, or reduce the tendency to snag on, the deployed suture wire (
It will be appreciated that suturing instrument 10 will have application in a broad range of different suturing operations. More particularly, it will be appreciated that suturing instrument 10 will have application in both “open” and “closed” surgical procedures, with the former including, but not limited to, large entry procedures, relatively shallow procedures, and surface procedures; and with the latter including, but not limited to, surgical procedures where access is gained to an interior structure through the use of a cannula, and surgical procedures where access is gained directly to an internal body cavity without the use of a cannula, e.g., such as a procedure conducted within the colon or the esophagus.
It will also be appreciated that suturing instrument 10 will have application where two portions of tissue must be attached to one another (e.g., where two severed pieces of tissue must be re-attached to one another, or where two separate pieces of tissue must be attached to one another, or where two sections of a single piece of tissue must be approximated to one another), and where an object must be attached to the patient (e.g., where surgical mesh must be attached to the patient's abdominal wall during hernia repair surgery, etc.).
Among other things, it is believed that suturing instrument 10 will have particular application in the areas of general laparoscopic surgery, general thoracic surgery, cardiac surgery, general intestinal surgery, vascular surgery, skin surgery and plastic surgery.
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It is also possible to use suturing instrument 10 to ligate a subject rather than to pass a suture through the subject. For example, suturing instrument 10 might be used to ligate a blood vessel with suture wire 58. In this case, suturing instrument 10 is deployed so that suture wire 58 will pass around the far side of the subject, rather than through the subject as in the case of the suturing operation of the type described above.
By way of example but not limitation, in a typical ligating operation, movable jaw portion 98 is first opened relative to fixed jaw portion 96. Then suturing instrument 10 is positioned about the subject so that when movable jaw portion 98 is thereafter closed toward fixed jaw portion 96, the fixed jaw portion's channel 108 and the movable jaw portion's opening 113 will both lie on the far side of the subject. The movable jaw portion 98 is then closed against the fixed jaw portion 96, and suture wire 58 is passed from fixed jaw portion 96 to movable jaw portion 98, i.e., around the far side of the subject. The movable jaw portion 98 is then opened, and suture wire 58 is payed out as the instrument is stepped back from the subject. Then the movable jaw portion 98 is again closed against the fixed jaw portion 96. The shaft of the instrument is then rotated so as to form, and then close down, the ligating loop. Then cutting bar 104 is activated so as to cut the ligating loop from the remainder of the suture wire still in the tool, the movable jaw member 98 is opened, and the instrument is withdrawn from the surgical site. The deployed suture wire 58 may then be pressed down flat against the subject, or rounded into a ball, or otherwise operated upon, so as to reduce the profile of, or reduce the tendency to snag on, the deployed suture wire. As will be appreciated by a person skilled in the art, where instrument 10 is to be used for ligating purposes, fixed jaw portion 96 and movable jaw portion 98 might be formed with a greater longitudinal length so as to facilitate passing the suture wire around the far side of the subject. Furthermore, movable jaw member 98 might be formed with a recess, intermediate its jaw linkage pin 100 (
Suture wire 58 may comprise a wire formed out of a metal or any other suitable material having the required flexibility and stiffness. By way of example but not limitation, suture wire 58 may comprise stainless steel, titanium, tantalum, etc.
If desired, suture wire 58 may also be coated with various active agents. For example, suture wire 58 may be coated with an anti-inflammatory agent, or an anti-coagulant agent, or an antibiotic, or a radioactive agent, etc.
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A piezoelectric element 200 is placed at the outside radius of the wire guide path 108 at the right angle bend in the fixed jaw portion 96 just before where the wire enters the tissue. The piezoelectric element 200 vibrates at a position along this bend such that it supports the wire in completing the turn but also imparts a component of displacement in the direction of the tissue. Displacement of this kind at ultrasonic frequencies, in addition to the existing wire driving means, would cause the tip of the wire to penetrate the tissue using less force. In addition to reducing the tendency for outright wire buckling, lowering the wire loads will also allow the wire penetration to proceed in a straighter path.
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If desired, the end effector 18 of suturing instrument 10 may be constructed so as to have two movable, opposing jaws, rather than one fixed jaw and one movable jaw as described above.
Also, if desired, shaft rotation motor 60 and thumb buttons 26, 28 may be configured so that depressing one button (e.g., button 26) will cause end effector 18 to rotate in one direction (e.g., clockwise), and depressing the other button (e.g., button 28) will cause end effector 18 to rotate in the opposite direction (e.g., counterclockwise).
Other Suture Materials
It is possible to use other suture wire materials provided they are stiff enough to penetrate the tissue. Other medical grade metals such as ASTM 1341 titanium and ASTM F 1091 cobalt-chromium alloy. Plastic materials that are sufficiently stiff could also be used such as polymide thermoplastics, Nylon, and polypropylene.
Collet Wire Drive Mechanism
Pushing the wire forward could also be done using a collet system such as sometimes used to drive lead in a mechanical pencil. The collet system could be smaller than the drive wheel mechanism and would allow it to be placed near the end of the instrument shaft. The collet would hold the wire and a mechanism would then push the collet and wire forward. An example of a collet wire drive mechanism 500 is shown in
As the collet 515 advances, wire 520 in front of collet 515 needs to be supported to prevent wire 515 from buckling, yet the support must shrink and expand with the motion of the collet movement. As shown in
Because collets for very small wires can be difficult to manufacture, small pieces of plastic tubing 565 with a small internal diameter sufficient to accommodate the wire with some clearance, can be placed in collet 515 as an interface between collet 515 and the wire. The deformability of the plastic tubing will allow collet 515 to collapse plastic tube 565 enough to press and hold the wire (see
It is advantageous to cut wire 520 with a minimum of force since the mechanism for cutting wire 520 has to be at the end of a small shaft. Providing the cutting surfaces with stress concentrators 570, 575 can substantially reduce the load required to cut the wire (see
It is also advantageous to provide wire 520 with a sharp tip 580 after cutting so that when it is pushed through tissue during the next suture placement it can be done with a minimum of force. Forcing a symmetric wedge-shaped cutting surface 570 into wire 520 from both sides will cause wire 520 to have a tip 585 with sloped sides making it sharper for tissue penetration (see
Wire Feed Stop
The moveable side of the jaw that accommodates the distal end of wire 520 as it passes through tissue 605 may include a stop to prevent excess wire advancement into surrounding tissues in surgical settings where it is difficult to see. The stop can be as simple as a physical end 610 to the hole in the jaw that the wire moves into after it has passed through the tissue. Alternatively, the wire end could be sensed as it passes into the moveable side of the jaw with devices such as an optical interrupter 615, pressure switch 620, or the like that would be used to provide an audible, tactile, or visual feedback to the surgeon indicating that they should stop advancing wire (see
Jaw Surfaces that Enhance Tissue Grasping
A large function of the jaw is to bring together the two pieces of tissue that are to be sutured. To facilitate this, the jaw surface may have undulations 625, abrasive surfaces 630, or concave areas 635 that create a ridge at the tip of the jaw. The jaw may also be tapered to a pointed tip 640 to increase its ability to pinch or isolate smaller sections of tissue. During hernia repairs, it is often necessary to attach a tightly woven mesh to the inside of the abdominal wall. The mesh can be anchored by using sutures placed through the mesh and into the tissue on the other side. In order for this to be feasible with the present device, the jaws must be able to grab a substantially flat section of mesh overlying tissue and pinch them in order to position them in the jaw. Once the mesh and tissue is properly positioned in the jaw, the wire can be passed through the tissue and twisted as is normally done (see
Jaw Feature that Facilitates Wire Penetration
A raised portion 645 on the jaw surface where wire 520 exists and also on the opposite jaw surface through which wire 520 passes after penetrating tissue 605, can reduce the travel distance of the wire. This reduces the chances that the wire will deviate from the intended path through the tissue (see
It is often necessary to surgically occlude a tubular structure 650 by tying a suture 655 tightly around the circumference so that the lumen is collapsed and closed. By placing a space 660 in the jaw proximal to where wire 520 emanates, a tubular structure 650 can be held in the closed jaw while wire is passed around the distal side of the structure. The jaw is then opened and pulled back while wire is being advanced. When wire is completely around it, the jaws are closed and the wire is twisted until the structure is occluded (see
The wire may be colored to make it easier to see in the video monitors used for minimally invasive surgery. The colorings may also be striped so that wire advance can more easily be seen. The wire may also be made with a matte finish to reduce the glare and enhance visibility.
The wire can be coated with anti-coagulant materials so that when it is used in vascular procedures it will not promote the formation of clots. To decrease the chances of infection, the wire can be coated with antibiotics. In order to reduce damage and inflammation to the vessel wall due to the presence of the wire, the wire can be coated with an anti-inflammatory agent. The wire may also be coated with a lubricant to facilitate its penetration through tissue.
To increase the outer diameter of the wire without making it more stiff, the wire can be coated with a biologically inert material such as Teflon. This would be useful when suturing tissue that is weak or thin because the larger diameter would decrease the stress that the suture places on those tissues. It would also require less torque to twist the ends together than a solid metal wire of comparable size.
Shaft that Allows Angled Orientation of Jaw
The surgical field often requires that the device access an area that is not in a straight line from the entrance point of the Instrument 662. One method for doing this with the present device is to give the outer tube 665 of the device shaft a permanent bend θ and allow all the inner tubes 670 (e.g. those that control the jaw, wire cutting, jaw rotation, etc.) to flex through this region. The outer tube of the shaft must be rigid so that the jaw maintains its orientation when it is rotated during wire twisting (see
Wire Disposable Details
The instrument will use single-use quantities of wire 520 that are sterile and disposable. The disposable consists of a plastic container 685 that contains the wire and a tube 690 that supports wire 520. Tube 690 projects from the middle of container 685 and is open to the wire reservoir at the proximal end. The disposable is manufactured with wire coiled in the container and fed through the distal end of the tube (see
The wire tube has a section 710 at the position of the drive wheels that is cut away on both sides to expose the wire to the drive wheel surfaces 700 (see
Because the wire tube is weak at the cutaway section for the wire, a structure that is connected to the container supports this section of the tube (see
Lubricious Wire Pathways
In order to reduce the forces needed to drive the wire and to increase the amount of force reaching the tip of the wire during tissue penetration, the frictional resistance of the wire moving against the walls of the wire tube can be reduced by using a material with a low coefficient of friction. This is especially important where the wire makes a 90 degree turn from a longitudinal direction along the instrument shaft to a direction that is perpendicular to the jaw structure. Teflon is very lubricous and it can easily be made into tubes with small internal diameters.
Wire Drive Wheels with Enhanced Frictional Force against the Wire
Because the contact area of the drive wheel to the wire is very small and a normal force is required to develop a frictional force to thrust the wire, the stresses in the wire can become large enough to permanently deform the wire. If the wire encounters a very hard material that stops its advance, the drive wheel can skid along the surface causing more stresses that can cause further permanent deformations, principally on one side of the wire. Those permanent deformations can cause the drive wheel to become stuck in a section of reduced wire diameter such that the wire cannot advance. Also, sections of wire can be created that have unilateral and bilateral radii that can promote premature buckling of the wire either within the instrument or at the site of tissue penetration. To decrease the normal force of the drive wheel against the wire, the coefficient of friction between the two can be increased by treating the surface 715 of the drive wheel 700A. Examples of such treatments are machining small scratches on the drive wheel surface perpendicular to the direction of wire travel or bead blasting a rough surface onto the drive wheel. Material coatings can also be added to the surface of the drive wheel such as deposition of diamond particles (see
Another means of increasing the frictional force is to increase the area of contact between drive wheel 700A and wire 520. This could be accomplished by placing a groove 720 into the drive wheel surface that wire 520 can partially fit into so that the drive wheel 700A also contacts the sides of wire 520. Also, both wheels 700A, 700B could be driven to increase the driving force. Yet another method to increase the surface area between the drive wheel and the wire, is to have multiple drive wheels 725 in series driven by a common or separate linkage (see
Jaw Rotational Symmetry
After the wire has been passed through the tissue and the wire ends are to be twisted together, it is important that the jaws have rotational symmetry so that while they are rotating they do not scrape or catch the surrounding tissue.
Means to Grab Separated Pieces of Tissue
Because the tissue pieces 730A, 730B to be approximated are often not near each other in the surgical field, it is beneficial for the instrument to bring them together. One or more of the jaw surfaces may have a small tooth or fang 740 that catches the tissue so that the jaw can be left open and moved to the other piece of tissue and positioned such that when the jaw is closed it has grasped both pieces of tissue in an optimized approximation. Wire suturing and twisting proceeds as normal thereafter (see
It will be appreciated by those skilled in the art that numerous modifications and variations may be made to the above-disclosed embodiments without departing from the spirit and scope of the present invention.