Patent Description:
Electrosurgical instruments have become widely used by surgeons. Electrosurgery involves the application of electrical energy and/or electromagnetic energy to cut, dissect, ablate, coagulate, cauterize, seal or otherwise treat biological tissue during a surgical procedure. Electrosurgery is typically performed using an electrosurgical generator operable to output energy and a handpiece including a surgical instrument (e.g., end effector) adapted to transmit energy to a tissue site during electrosurgical procedures. Electrosurgery can be performed using either a monopolar or a bipolar instrument.

The basic purpose of both monopolar and bipolar electrosurgery is to produce heat to achieve the desired tissue/clinical effect. In monopolar electrosurgery, devices use an instrument with a single, active electrode to deliver energy from an electrosurgical generator to tissue. In monopolar electrosurgery, a patient return electrode, also called a grounding pad, bovie pad, neutral electrode or patient plate, is attached externally to the patient (e.g., a plate positioned on the patient's thigh or back) as the means to complete the electrical circuit between the electrosurgical generator and the patient. When the electrosurgical energy is applied, the energy travels from the active electrode, to the surgical site, through the patient and to the return electrode. In bipolar electrosurgery, both the active electrode and return electrode functions are performed at the site of surgery. Bipolar electrosurgical devices include two electrodes of opposite polarity that are located in proximity to one another for the application of current between their surfaces. Bipolar electrosurgical current travels from one electrode, through the intervening tissue to the other electrode to complete the electrical circuit, thereby eliminating the need for a remotely-located current return. Bipolar instruments generally include end-effectors, such as grippers, cutters, forceps, dissectors and the like.

Forceps utilize mechanical action to constrict, grasp, dissect and/or clamp tissue. By utilizing an electrosurgical forceps, a surgeon can utilize both mechanical clamping action and electrosurgical energy to effect hemostasis by heating the tissue and blood vessels to cauterize, coagulate/desiccate, seal and/or divide tissue. Bipolar electrosurgical forceps utilize two generally opposing electrodes that are operably associated with the inner opposing surfaces of an end effector and that are both electrically coupled to an electrosurgical generator. In bipolar forceps, the end-effector assembly generally includes opposing jaw assemblies pivotably mounted with respect to one another. In bipolar configuration, only the tissue grasped between the jaw assemblies is included in the electrical circuit.

By utilizing an electrosurgical forceps, a surgeon can cauterize, coagulate/desiccate and/or seal tissue and/or simply reduce or slow bleeding by controlling the intensity, frequency and duration of the electrosurgical energy applied through the jaw assemblies to the tissue. During the sealing process, mechanical factors such as the pressure applied between opposing jaw assemblies and the gap distance between the electrically-conductive tissue-contacting surfaces (electrodes) of the jaw assemblies play a role in determining the resulting thickness of the sealed tissue and effectiveness of the seal.

A variety of types of end-effector assemblies have been employed for various types of electrosurgery using a variety of types of monopolar and bipolar electrosurgical instruments. A device according to the preamble of claim <NUM> is known from <CIT>.

A continuing need exists for jaw assembly components that can be readily integrated into manufacturing assembly processes for the production of end-effector assemblies for use in electrosurgical instruments, such as electrosurgical forceps.

According to an aspect of the present disclosure, an end-effector assembly is provided. The end-effector assembly includes opposing first and second jaw assemblies, at least one of the first and second assemblies is movable relative to the other from a first position wherein the jaw assemblies are disposed in spaced relation relative to one another to at least a second position closer to one another wherein the jaw assemblies cooperate to grasp tissue therebetween. The first jaw assembly includes a first housing and a first electrically-conductive tissue-engaging structure associated with at least a portion of the first housing. The second jaw assembly includes a second housing and a second electrically-conductive tissue-engaging structure associated with at least a portion of the second housing. The end-effector assembly also includes a dissector electrode coupled along at least a portion of a lateral side portion of either one of the first housing or the second housing. The dissector electrode is electrically-isolated from the first and second electrically-conductive tissue-engaging structures.

According to another aspect of the present disclosure, a bipolar forceps is provided. The bipolar forceps includes a housing having a shaft affixed thereto. The shaft includes opposing jaw assemblies attached to a distal end thereof. At least one of jaw assemblies is movable relative to the other from a first position wherein the jaw assemblies are disposed in spaced relation relative to one another to at least a second position closer to one another wherein the jaw assemblies cooperate to grasp tissue therebetween. Each jaw assembly includes an outer housing and an electrically-conductive tissue-engaging structure associated with at least a portion of the outer housing. The bipolar forceps also includes one or more dissector electrodes coupled along at least a portion of a lateral side portion of either one of housings. The one or more dissector electrodes are electrically-isolated from the electrically-conductive tissue-engaging structures. A current return path during activation of the at least one dissector electrode includes either one of the electrically-conductive tissue-engaging structures.

According to another aspect of the present disclosure, a bipolar forceps is provided that includes a housing having a shaft affixed thereto. The shaft includes first and second jaw assemblies attached to a distal end thereof. At least one of the first and second jaw assemblies is movable relative to the other from a first position wherein the jaw assemblies are disposed in spaced relation relative to one another to at least a second position closer to one another wherein the jaw assemblies cooperate to grasp tissue therebetween. The first jaw assembly includes a first outer housing and a first electrically-conductive tissue-engaging structure disposed in association with at least a portion of the first outer housing. The second jaw assembly includes a second outer housing and a second electrically-conductive tissue-engaging structure disposed in association with at least a portion of the second outer housing. The bipolar forceps also includes first and second dissector electrodes. The first dissector electrode is coupled along at least a portion of a first lateral side of the first outer housing, wherein the first dissector electrode is electrically-isolated from the first electrically-conductive tissue-engaging structure. The second dissector electrode is coupled along at least a portion of a second lateral side of the second outer housing, wherein the second dissector electrode is electrically-isolated from the second electrically-conductive tissue-engaging structure. The bipolar forceps is adapted to allow each one of the first and second dissector electrodes to be individually activated.

Objects and features of the presently-disclosed jaw assemblies including an electrode adapted for tissue dissection and coagulation for use in electrosurgical instruments will become apparent to those of ordinary skill in the art when descriptions of various embodiments thereof are read with reference to the accompanying drawings, of which:.

Hereinafter, embodiments of jaw assemblies for use in electrosurgical instruments of the present disclosure are described with reference to the accompanying drawings. Like reference numerals may refer to similar or identical elements throughout the description of the figures. As shown in the drawings and as used in this description, and as is traditional when referring to relative positioning on an object, the term "proximal" refers to that portion of the apparatus, or component thereof, closer to the user and the term "distal" refers to that portion of the apparatus, or component thereof, farther from the user.

This description may use the phrases "in an embodiment," "in embodiments," "in some embodiments," or "in other embodiments," which may each refer to one or more of the same or different embodiments in accordance with the present disclosure.

Various embodiments of the present disclosure provide electrosurgical instruments suitable for sealing, cauterizing, coagulating/desiccating, cutting and/or dissecting vessels and vascular tissue. Various embodiments of the present disclosure provide an electrosurgical forceps with an end-effector assembly including two jaw assemblies disposed in opposing relation relative to one another. Various embodiments of the presently-disclosed jaw assemblies include one or more dissector electrodes adapted for tissue dissection and coagulation. Embodiments of the presently-disclosed end-effector assemblies may include jaw assemblies arranged in a unilateral or bilateral configuration.

Embodiments of the presently-disclosed electrosurgical forceps including a dissector electrode may be suitable for utilization in endoscopic surgical procedures and/or suitable for utilization in open surgical applications. Embodiments of the presently-disclosed electrosurgical instruments may be connected through a suitable bipolar cable to a generator and/or other suitable power source. Although the following description describes the use of an endoscopic bipolar forceps, the teachings of the present disclosure may also apply to a variety of electrosurgical devices that include jaw assemblies.

The various embodiments disclosed herein may also be configured to work with robotic surgical systems and what is commonly referred to as "Telesurgery. " Such systems employ various robotic elements to assist the surgeon in the operating theater and allow remote operation (or partial remote operation) of surgical instrumentation. Various robotic arms, gears, cams, pulleys, electric and mechanical motors, etc. may be employed for this purpose and may be designed with a robotic surgical system to assist the surgeon during the course of an operation or treatment. Such robotic systems may include remotely steerable systems, automatically flexible surgical systems, remotely flexible surgical systems, remotely articulating surgical systems, wireless surgical systems, modular or selectively configurable remotely operated surgical systems, etc..

The robotic surgical systems may be employed with one or more consoles that are next to the operating theater or located in a remote location. In this instance, one team of surgeons or nurses may prep the patient for surgery and configure the robotic surgical system with one or more of the instruments disclosed herein while another surgeon (or group of surgeons) remotely control the instruments via the robotic surgical system. As can be appreciated, a highly skilled surgeon may perform multiple operations in multiple locations without leaving his/her remote console which can be both economically advantageous and a benefit to the patient or a series of patients.

The robotic arms of the surgical system are typically coupled to a pair of master handles by a controller. The handles can be moved by the surgeon to produce a corresponding movement of the working ends of any type of surgical instrument (e.g., end effectors, graspers, knifes, scissors, etc.) which may complement the use of one or more of the embodiments described herein. The movement of the master handles may be scaled so that the working ends have a corresponding movement that is different, smaller or larger, than the movement performed by the operating hands of the surgeon. The scale factor or gearing ratio may be adjustable so that the operator can control the resolution of the working ends of the surgical instrument(s).

The master handles may include various sensors to provide feedback to the surgeon relating to various tissue parameters or conditions, e.g., tissue resistance due to manipulation, cutting or otherwise treating, pressure by the instrument onto the tissue, tissue temperature, tissue impedance, etc. As can be appreciated, such sensors provide the surgeon with enhanced tactile feedback simulating actual operating conditions. The master handles may also include a variety of different actuators for delicate tissue manipulation or treatment further enhancing the surgeon's ability to mimic actual operating conditions.

in <FIG>, an embodiment of an endoscopic bipolar forceps <NUM> is shown for use with various surgical procedures and generally includes a housing <NUM>, a handle assembly <NUM>, a rotatable assembly <NUM>, a trigger assembly <NUM>, and an end-effector assembly <NUM>. End-effector assembly <NUM> generally includes two jaw assemblies <NUM> and <NUM> disposed in opposing relation relative to one another. An embodiment of the end-effector assembly <NUM>, in accordance with the present disclosure, is shown in more detail in <FIG>. It is to be understood, however, that other end-effector embodiments may also be used. One or more components of the bipolar forceps <NUM>, e.g., the housing <NUM>, the handle assembly <NUM>, the rotatable assembly <NUM>, the trigger assembly <NUM>, and/or the end-effector assembly <NUM>, may be adapted to mutually cooperate to grasp, seal and/or divide tissue, e.g., tubular vessels and vascular tissue (not shown). Forceps <NUM> may include additional, fewer, or different components than shown in <FIG>, depending upon a particular purpose or to achieve a desired result.

End-effector assembly <NUM> includes a dissector electrode <NUM> adapted for tissue dissection and coagulation. Dissector electrode <NUM>, which is described in more detail later in this description, may include any suitable electrically-conductive material, including, without limitation, metals, metal alloys, electrically-conductive polymers, and composite materials. Dissector electrode <NUM> may be formed as a multi-layer configuration of materials. In some embodiments, one or more portions of the dissector electrode <NUM>, e.g., an inner-facing surface(s) thereof, may include an non-electrically-conductive or substantially non-electrically-conductive material configured to provide for electrical isolation between electrically-conductive elements of the dissector electrode <NUM> (e.g., tip portion <NUM> and/or shoulder portion <NUM>) and one or more jaw assembly components, e.g., to reduce the chances of short circuiting the jaw assemblies <NUM> and <NUM> during activation, and/or to facilitate assembly and/or to meet specific tolerance requirements for proper jaw alignment, thermal resistance, strength and rigidity, which play a role in determining the reliability and effectiveness of electrosurgical instruments.

In some embodiments, as shown in <FIG>, the end-effector assembly <NUM> includes jaw assemblies <NUM> and <NUM> in a unilateral configuration and the dissector electrode <NUM> is disposed in association with the movable jaw assembly <NUM>. In alternative embodiments, a dissector electrode adapted for tissue dissection and coagulation (e.g., dissector electrode <NUM> shown in <FIG>) may be disposed in association with the fixed jaw assembly (e.g., <NUM> shown in <FIG>). In alternative embodiments, wherein two jaw assemblies disposed in opposing relation relative to one another are arranged in a bilateral configuration, a dissector electrode in accordance with the present disclosure may be disposed in association either one of the bilateral jaw assemblies.

Although <FIG> depicts a bipolar forceps <NUM> for use in connection with endoscopic surgical procedures, the teachings of the present disclosure may also apply to more traditional open surgical procedures. For the purposes herein, the forceps <NUM> is described in terms of an endoscopic instrument; however, an open version of the forceps (e.g., bipolar forceps <NUM> shown in <FIG>) may also include the same or similar operating components and features as described below.

Forceps <NUM> includes a shaft <NUM> having a distal end <NUM> configured to mechanically engage the end-effector assembly <NUM> and a proximal end <NUM> configured to mechanically engage the housing <NUM>. In some embodiments, the shaft <NUM> has a length from the proximal side of the handle assembly <NUM> to the distal side of the forceps <NUM> in a range of about <NUM> centimeters to about <NUM> centimeters. End-effector assembly <NUM> may be selectively and releaseably engageable with the distal end <NUM> of the shaft <NUM>, and/or the proximal end <NUM> of the shaft <NUM> may be selectively and releaseably engageable with the housing <NUM> and the handle assembly <NUM>.

The proximal end <NUM> of the shaft <NUM> is received within the housing <NUM>, and connections relating thereto are disclosed in commonly assigned <CIT> entitled "METHOD OF MANUFACTURING JAW ASSEMBLY FOR VESSEL SEALER AND DIVIDER," commonly assigned <CIT> entitled "VESSEL SEALER AND DIVIDER FOR USE WITH SMALL TROCARS AND CANNULAS," commonly assigned <CIT> entitled "VESSEL SEALER AND DIVIDER FOR USE WITH SMALL TROCARS AND CANNULAS" and commonly assigned <CIT> entitled "VESSEL SEALER AND DIVIDER HAVING A VARIABLE JAW CLAMPING MECHANISM.

In some embodiments, as shown in <FIG>, forceps <NUM> includes an electrosurgical cable <NUM>. Electrosurgical cable <NUM> may be formed from a suitable flexible, semi-rigid or rigid cable, and may connect directly to an electrosurgical power generating source <NUM>. In some embodiments, the electrosurgical cable <NUM> connects the forceps <NUM> to a connector <NUM>, which further operably connects the instrument <NUM> to the electrosurgical power generating source <NUM>. Cable <NUM> may be internally divided into one or more cable leads each of which transmits energy through their respective feed paths to the end-effector assembly <NUM>.

Electrosurgical power generating source <NUM> may be any generator suitable for use with electrosurgical devices, and may be configured to provide various frequencies of electromagnetic energy. Examples of electrosurgical generators that may be suitable for use as a source of electrosurgical energy are commercially available under the trademarks FORCE EZ™, FORCE FX™, and FORCE TRIAD™ sold by Covidien Surgical Solutions of Boulder, CO. Forceps <NUM> may alternatively be configured as a battery-powered wireless instrument.

End-effector assembly <NUM> may be configured as a unilateral assembly, i.e., the end-effector assembly <NUM> may include a stationary or fixed jaw assembly, e.g., <NUM>, mounted in fixed relation to the shaft <NUM>, and a moveable jaw assembly, e.g., <NUM>, mounted about a pivot pin <NUM> coupled to the fixed jaw assembly. Alternatively, the forceps <NUM> may include a bilateral assembly, i.e., both jaw assemblies <NUM> and <NUM> are moveable relative to one another. Jaw assemblies <NUM> and <NUM> may be curved at various angles to facilitate manipulation of tissue and/or to provide enhanced line-of-sight for accessing targeted tissues.

As shown in <FIG>, the end-effector assembly <NUM> is rotatable about a longitudinal axis "X - X" through rotation, either manually or otherwise, of the rotatable assembly <NUM>. Rotatable assembly <NUM> generally includes two halves (not shown), which, when assembled about a tube of shaft <NUM>, form a generally circular rotatable member <NUM>. Rotatable assembly <NUM>, or portions thereof, may be configured to house a drive assembly (not shown) and/or a knife assembly (not shown), or components thereof. A reciprocating sleeve (not shown) is slidingly disposed within the shaft <NUM> and remotely operable by the drive assembly (not shown). Examples of rotatable assembly embodiments, drive assembly embodiments, and knife assembly embodiments of the forceps <NUM> are described in the above-mentioned, commonly-assigned <CIT>, <CIT>, <CIT>and<CIT>.

Handle assembly <NUM> includes a fixed handle <NUM> and a movable handle <NUM>. In some embodiments, the fixed handle <NUM> is integrally associated with the housing <NUM>, and the movable handle <NUM> is selectively movable relative to the fixed handle <NUM>. Movable handle <NUM> of the handle assembly <NUM> is ultimately connected to the drive assembly (not shown). As can be appreciated, applying force to move the movable handle <NUM> toward the fixed handle <NUM> pulls the drive sleeve (not shown) proximally to impart movement to the jaw assemblies <NUM> and <NUM> from an open position, wherein the jaw assemblies <NUM> and <NUM> are disposed in spaced relation relative to one another, to a clamping or closed position, wherein the jaw assemblies <NUM> and <NUM> cooperate to grasp tissue therebetween. Examples of handle assembly embodiments of the forceps <NUM> are described in the above-mentioned, commonly-assigned <CIT>, <CIT>, <CIT> and <CIT>.

Forceps <NUM> includes a switch <NUM> configured to permit the user to selectively activate the forceps <NUM> in a variety of different orientations, i.e., multi-oriented activation. As can be appreciated, this simplifies activation. When the switch <NUM> is depressed, electrosurgical energy is transferred through one or more electrical leads (not shown) to the jaw assemblies <NUM> and <NUM>. Although <FIG> depicts the switch <NUM> disposed at the proximal end of the housing assembly <NUM>, switch <NUM> may be disposed on another part of the forceps <NUM> (e.g., the fixed handle <NUM>, rotatable member <NUM>, etc.) or another location on the housing assembly <NUM>.

Jaw assemblies <NUM> and <NUM>, as shown in <FIG> and <FIG>, include an electrically-conductive tissue-engaging surface or sealing plate <NUM> and <NUM>, respectively, arranged in opposed relation relative to one another and disposed in association with an outer housing <NUM> and <NUM>, respectively (<FIG>). In some embodiments, the outer housings <NUM> and <NUM> define a cavity therein configured to at least partially encapsulate and/or securely engage the sealing plates <NUM> and <NUM>, respectively, and/or other jaw assembly components.

In some embodiments, the outer housings <NUM> and <NUM> may be formed, at least in part, of an non-electrically-conductive or substantially non-electrically-conductive material. Outer housing <NUM> and/or the outer housing <NUM> include one or more electrically-conductive portions suitably disposed relative to the dissector electrode <NUM> to provide a current return path. In some embodiments, as shown in <FIG>, the outer housing <NUM> includes two electrically-conductive portions <NUM> and <NUM> configured to provide a current return path. The shape, size, and relative location of the electrically-conductive portions <NUM> and <NUM>, e.g., in relation to the dissector electrode <NUM>, may be varied from the configuration depicted in <FIG>. Additionally, or alternatively, the outer housing <NUM> may include one or more electrically-conductive portions suitably disposed to provide a current return path.

Dissector electrode <NUM> includes a tip portion <NUM> and a shoulder portion <NUM>. In some embodiments, the tip portion <NUM> may extend distally beyond the distal end <NUM> of the outer housing <NUM>. Tip portion <NUM> may be configured to provide a desired function, and may include curves at various angles to facilitate contact with targeted tissue. In some embodiments, the tip portion <NUM> is configured for dissection, and may include a sharp knife edge, a blunt tip, a blunt edge, paddle, hook, a ball-shaped portion, or another shape. Shoulder portion <NUM> extends along at least a portion of a lateral side portion of the outer housing <NUM>. In some embodiments, the shoulder portion <NUM> is configured for coagulation. The shape and size of the shoulder portion <NUM> may be varied from the configuration depicted in <FIG> and <FIG>, e.g., depending upon a particular purpose.

Sealing plates <NUM> and <NUM> may be adapted to connect to an electrosurgical energy source (e.g., <NUM> shown in <FIG>) independently of one another such that either or both of the sealing plates <NUM> and <NUM> may be selectively energized, depending on a particular purpose. In some embodiments, the jaw assembly <NUM> is connected to a first electrical lead (not shown) and the jaw assembly <NUM> is connected to a second electrical lead (not shown), which, in turn, are electrically coupled with an electrosurgical energy source (e.g., <NUM> shown in <FIG>). In some embodiments, the first and second electrical leads terminate within the outer housings <NUM> and <NUM>, respectively, e.g., electro-mechanically coupled to the sealing plates <NUM> and <NUM>, respectively, and may allow a user to selectively supply either bipolar or monopolar electrosurgical energy to the jaw assemblies <NUM> and <NUM> as needed during surgery. Activation switch <NUM> (<FIG>) is selectively actuatable to control the supply of energy to the sealing plates <NUM> and <NUM>. Activation switch <NUM> may include one or more switch components to facilitate selective activation of either or both of the sealing plates <NUM> and <NUM>.

One or both of the jaw assemblies <NUM> and <NUM> include a longitudinally-oriented slot or knife channel configured to permit reciprocation of a knife blade (not shown). In some embodiments, as shown in <FIG>, the knife channel <NUM> may be completely disposed in one of the two jaw assemblies, e.g., jaw assembly <NUM>, depending upon a particular purpose.

Examples of sealing plate <NUM>, <NUM>, outer housing <NUM>, <NUM>, and knife blade embodiments are disclosed in commonly assigned International Application Serial No. <CIT>, entitled "ELECTROSURGICAL INSTRUMENT WHICH REDUCES COLLATERAL DAMAGE TO ADJACENT TISSUE," and commonly assigned International Application Serial No. <CIT>, entitled "ELECTROSURGICAL INSTRUMENT REDUCING FLASHOVER.

In <FIG>, an embodiment of an open forceps <NUM> is shown for use with various surgical procedures and generally includes an end effector assembly <NUM> operably associated with a pair of opposing shafts 212a and 212b and disposed in association with the distal ends 216a and 216b thereof, respectively. End effector assembly <NUM> includes a first jaw member <NUM> and a second jaw member <NUM> disposed in opposing relation relative to one another and pivotably connected about a pivot pin <NUM> and movable relative to one another to grasp tissue.

Shaft 212a includes a handle <NUM> disposed in association with the proximal end 214a thereof. Shaft 212b includes a handle <NUM> disposed in association with the proximal end 214b thereof. Handles <NUM> and <NUM> define a finger and/or thumb hole 215a and 217a, respectively, therethrough for receiving the user's finger or thumb. Finger and/or thumb holes 215a and 217a facilitate movement of the shafts 212a and 212b relative to one another to pivot the first and second jaw members <NUM> and <NUM> from an open position, wherein the first and second jaw members <NUM> and <NUM> are disposed in spaced relation relative to one another, to a clamping or closed position, wherein the first and second jaw members <NUM> and <NUM> cooperate to grasp tissue therebetween.

End-effector assembly <NUM> includes a dissector electrode <NUM> adapted for tissue dissection and coagulation. Dissector electrode <NUM> includes a shoulder portion <NUM>. The shape and size of the shoulder portion <NUM> may be varied from the configuration depicted in <FIG>, e.g., depending upon a particular purpose. Dissector electrode <NUM> may include a tip portion <NUM>.

In some embodiments, as shown in <FIG>, the dissector electrode <NUM> is disposed in association with the first jaw member <NUM>. In alternative embodiments, the dissector electrode <NUM> may be disposed in association with the second jaw member <NUM>. Dissector electrode <NUM> include any suitable electrically-conductive material, and may be formed as a multi-layer configuration of materials. In some embodiments, one or more portions of the dissector electrode <NUM> may include an non-electrically-conductive or substantially non-electrically-conductive material. Dissector electrode <NUM> shown in <FIG> is similar to the dissector electrode <NUM> shown in <FIG> and <FIG>, and further description of the like elements is omitted in the interests of brevity.

<FIG> show an end-effector assembly <NUM> in accordance with an embodiment of the present disclosure that includes a dissector electrode <NUM> adapted for tissue dissection and coagulation. Dissector electrode <NUM> includes a tip portion <NUM> and a shoulder portion <NUM> as best shown in <FIG>.

End-effector assembly <NUM> generally includes two jaw assemblies <NUM> and <NUM> disposed in opposing relation relative to one another. Jaw assemblies <NUM> and <NUM> each include an electrically-conductive tissue-engaging surface or sealing plate <NUM> and <NUM>, respectively, arranged in opposed relation relative to one another and disposed in association with an outer housing <NUM> and <NUM>, respectively.

Outer housings <NUM> and <NUM> generally include a distal end <NUM> and <NUM>, respectively, and two lateral side portions (e.g., first lateral side portion "S1" and second lateral side portion "S2" of the housing <NUM> shown in <FIG>). In some embodiments, the outer housings <NUM> and <NUM> may be formed, at least in part, of an non-electrically-conductive or substantially non-electrically-conductive material. Outer housing <NUM> and/or the outer housing <NUM> may include one or more electrically-conductive portions of suitable conductivity and so disposed in relation to one or more features of the dissector electrode <NUM> (e.g., tip portion <NUM> and/or shoulder portion <NUM>) to provide a current return path. In some embodiments, as shown in <FIG>, the outer housing <NUM> includes two electrically-conductive portions <NUM> and <NUM> configured to provide a current return path. The shape, size, and relative location of the electrically-conductive portions <NUM> and <NUM>, e.g., in relation to the dissector electrode <NUM>, may be varied from the configuration depicted in <FIG>.

In some embodiments, the tip portion <NUM> of the dissector electrode <NUM> may extend distally beyond the distal end <NUM> of the outer housing <NUM>. Tip portion <NUM> may be configured to provide a desired function, and may include curves at various angles to facilitate contact with targeted tissue. Tip portion <NUM> may include a sharp knife edge, a blunt tip, a blunt edge, paddle, hook, a ball-shaped portion, or another shape. Shoulder portion <NUM> extends along at least a portion of the first lateral side portion "S1" of the outer housing <NUM>. Shoulder portion <NUM> may have any suitable dimensions, e.g., length, width and height. The shape and size of the shoulder portion <NUM> may be varied from the configuration depicted in <FIG>. In some embodiments, the tip portion <NUM> is configured for dissection, and the shoulder portion <NUM> is configured for coagulation.

Dissector electrode <NUM> may include any suitable electrically-conductive material, including, without limitation, metals, metal alloys, electrically-conductive polymers, and composite materials. In some embodiments, one or more portions of the dissector electrode <NUM>, e.g., an inner-facing surface(s) thereof, may include an non-electrically-conductive or substantially non-electrically-conductive material configured to provide for electrical isolation between electrically-conductive elements of the dissector electrode <NUM> (e.g., tip portion <NUM> and/or shoulder portion <NUM>) and one or more jaw assembly components, e.g., to reduce the chances of short circuiting the jaw assemblies <NUM> and <NUM> during activation, and/or to facilitate assembly and/or to meet specific tolerance requirements for proper jaw alignment, thermal resistance, strength and rigidity, which play a role in determining the reliability and effectiveness of electrosurgical instruments.

In some embodiments, one or more portions of the dissector electrode <NUM>, e.g., an inner-facing surface(s) thereof, may include an non-electrically-conductive or substantially non-electrically-conductive material suitably configured to provide for electrical isolation between electrically-conductive elements of the dissector electrode <NUM> (e.g., tip portion <NUM> and/or shoulder portion <NUM>) and one or more jaw assembly components, e.g., to facilitate assembly and/or to meet specific tolerance requirements for proper jaw alignment, thermal resistance, strength and rigidity.

<FIG> show an end-effector assembly <NUM> in accordance with an embodiment of the present disclosure that includes a dissector electrode <NUM> adapted for tissue dissection and coagulation. End-effector assembly <NUM> generally includes two jaw assemblies <NUM> and <NUM> disposed in opposing relation relative to one another. Jaw assemblies <NUM> and <NUM> each include an tissue-engaging surface or sealing plate <NUM> and <NUM>, respectively, disposed in association with an outer housing <NUM> and <NUM>, respectively, and arranged in opposed relation relative to one another. Dissector electrode <NUM> is generally insulated from the sealing plates <NUM> and <NUM>. Dissector electrode <NUM> may be insulated, at least in part, from one or more electrically-conductive portions of the outer housing <NUM> and/or the outer housing <NUM>.

Outer housings <NUM> and <NUM> include distal ends <NUM> and <NUM>, respectively, and are configured to define two lateral side portions (e.g., first lateral side portion "S1" and second lateral side portion "S3" extending distally from the distal end <NUM> of the housing <NUM> as shown in <FIG>). Outer housings <NUM> and <NUM> may be formed, at least in part, of an electrically-insulative material. In some embodiments, the outer housing <NUM> and/or the outer housing <NUM> include a configuration of one or more electrically-conductive portions suitably disposed relative to the dissector electrode <NUM> to provide a current return path. In some embodiments, as shown in <FIG>, the outer housing <NUM> includes two electrically-conductive portions <NUM> and <NUM> configured to provide a current return path. The shape, size, and relative location of the electrically-conductive portions <NUM> and <NUM>, e.g., in relation to the dissector electrode <NUM>, may be varied from the configuration depicted in <FIG>.

Dissector electrode <NUM> may include any suitable electrically-conductive material, including, without limitation, metals, metal alloys, polymers, and composite materials. Dissector electrode <NUM> may be formed as a multi-layer configuration of materials. In some embodiments, one or more portions of the dissector electrode <NUM>, e.g., an inner-facing surface(s) thereof, may include an non-electrically-conductive or substantially non-electrically-conductive material suitably configured to provide for electrical isolation between electrically-conductive elements of the dissector electrode <NUM> (e.g., tip portion <NUM> and/or shoulder portion <NUM>) and a configuration of one or more electrically-conductive portions of the jaw assemblies <NUM> and <NUM>, e.g., to facilitate assembly, and/or to ensure electrical isolation either in connection with, or independently from, the configuration of electrically-insulative bushings used to electrically isolate the opposing jaw assemblies <NUM> and <NUM> from one another.

In alternative embodiments, a dissector electrode, and/or components thereof, e.g., a shoulder portion, may be disposed in association with the second lateral side portion "S4" of the outer housing <NUM>. In some embodiments, the end-effector assembly <NUM> may be configured with two dissector electrodes, e.g., disposed in association with each of the first and second lateral side portions "S3" and "S4", respectively, e.g., to allow the user flexibility in the use of the end-effector assembly <NUM> to facilitate tissue dissection and coagulation.

<FIG> shows an end-effector assembly <NUM> in accordance with an embodiment of the present disclosure that includes a first dissector electrode <NUM> and a second dissector electrode <NUM>, e.g., adapted for tissue dissection and coagulation. End-effector assembly <NUM> generally includes two jaw assemblies <NUM> and <NUM> disposed in opposing relation relative to one another. Jaw assemblies <NUM> and <NUM> each include an electrically-conductive tissue-engaging surface or sealing plate <NUM> and <NUM>, respectively, arranged in opposed relation relative to one another and disposed in association with an outer housing <NUM> and <NUM>, respectively. Jaw assemblies <NUM> and <NUM> shown in <FIG> are similar to the jaw assemblies <NUM> and <NUM>, respectively, shown in <FIG>, and further description thereof is omitted in the interests of brevity.

First dissector electrode <NUM> is coupled along at least a portion of a lateral side portion "S5" of the outer housing <NUM> and the second dissector electrode <NUM> is coupled along at least a portion of a lateral side portion "S6" of the outer housing <NUM>, such that the first and second dissector electrode <NUM> and <NUM>, respectively, are disposed on the opposite sides of the jaw assembly <NUM>. The first and second dissector electrodes <NUM> and <NUM>, respectively, are similar to the dissector electrode <NUM> shown in <FIG> and further description thereof is omitted in the interests of brevity.

<FIG> shows an end-effector assembly <NUM> in accordance with an embodiment of the present disclosure that includes a first dissector electrode <NUM> and a second dissector electrode <NUM>, e.g., adapted for tissue dissection and coagulation. End-effector assembly <NUM> generally includes two jaw assemblies <NUM> and <NUM> disposed in opposing relation relative to one another. Jaw assemblies <NUM> and <NUM> each include an electrically-conductive tissue-engaging surface or sealing plate <NUM> and <NUM>, respectively, arranged in opposed relation relative to one another and disposed in association with an outer housing <NUM> and <NUM>, respectively. Outer housing <NUM> includes a lateral side portion "S7" and a lateral side portion "S8", and the outer housing <NUM> includes a lateral side portion "S9" and a lateral side portion "S10".

In some embodiments, as show in <FIG>, the first dissector electrode <NUM> is coupled along at least a portion of the lateral side portion "S7" of the outer housing <NUM>, and the second dissector electrode <NUM> is coupled along at least a portion of the lateral side portion "S10" of the outer housing <NUM>, such that the first and second dissector electrode <NUM> and <NUM>, respectively, are disposed on the opposite sides of the jaw assemblies <NUM> and <NUM>, respectively. The first and second dissector electrodes <NUM> and <NUM>, respectively, are similar to the dissector electrode <NUM> shown in <FIG> and further description thereof is omitted in the interests of brevity. In any of the above-described embodiments, an end-effector assembly having a plurality of dissector electrodes may be adapted to allow the dissector electrodes to be individually activated, e.g., depending upon a particular purpose.

In alternative embodiments compatible with any of the above embodiments of dissector electrodes for assembly into jaw assembly configurations, an electrically-insulative bushing may be used to electrically isolate the opposing jaw members from one another, wherein a configuration of one or more electrically-insulative bushings may be associated with either or both jaw assemblies.

In some embodiments, a configuration of one or more electrically-insulative bushings may additionally, or alternatively, be associated with one or more dissector electrodes. In some embodiments, the electrically-insulative bushing may include ceramic or any of a variety of suitable non-electrically conductive materials such as polymeric materials, e.g., plastics, and/or other insulative materials. In other embodiments, other non-electrically conductive synthetic and/or natural materials having suitable weight, strength, cost and/or other characteristics may be used for the electrically-insulative bushing(s).

The above-described bipolar forceps embodiments that include a dissector electrode adapted for tissue dissection and coagulation are capable of directing energy into tissue, and may be suitable for use in a variety of procedures and operations. The above-described end-effector embodiments may utilize both mechanical clamping action and electrical energy to effect hemostasis by heating tissue and blood vessels to coagulate, cauterize, cut and/or seal tissue. The jaw assemblies may be either unilateral or bilateral. The above-described bipolar forceps embodiments that include a dissector electrode adapted for tissue dissection and coagulation may be suitable for utilization with endoscopic surgical procedures and/or hand-assisted, endoscopic and laparoscopic surgical procedures. The above-described bipolar forceps embodiments that include a dissector electrode adapted for tissue dissection and coagulation may be suitable for utilization in open surgical applications.

The above-described end-effector embodiments may be used in connection with sealing plates and support bases of jaw assemblies of varied geometries, e.g., lengths and curvatures, such that variously-configured jaw assemblies may be fabricated and assembled into various end-effector configurations that include a dissector electrode adapted for tissue dissection and coagulation, e.g., depending upon design of specialized electrosurgical instruments.

Claim 1:
An end-effector assembly (<NUM>), comprising:
opposing first (<NUM>) and second (<NUM>) jaw assemblies, at least one of the first and second jaw assemblies movable relative to the other from a first position wherein the jaw assemblies are disposed in spaced relation relative to one another to at least a second position wherein the jaw assemblies are closer to one another;
the first jaw assembly including:
a first housing (<NUM>); and
a first electrically-conductive tissue-engaging structure associated with at least a portion of the first housing;
the second jaw assembly including a second housing (<NUM>), a second electrically-conductive tissue-engaging structure associated with at least a portion of the second housing, and at least one of the first or second housings of the first and second jaw assemblies having an electrically-conductive outer surface (<NUM>, <NUM>) configured to be coupled to an electrosurgical power generating source; and characterised by
a dissector electrode (<NUM>) coupled along at least a portion of a lateral side of either one of the first housing or the second housing, wherein the dissector electrode is electrically-isolated from the first electrically-conductive tissue-engaging structure and the electrically-conductive outer surface of the at least one first or second housings.