Electrosurgical electrodes, methods for making electrosurgical electrodes, and electrosurgical instruments including electrosurgical electrodes

Abstract

The electrosurgical electrode (1; 23) comprises a conductive electrode body (2; 24) having a cutting portion (3; 25) configured to apply RF electrical energy to tissue and an opposing shank portion (5; 26) configured to couple to an electrosurgical instrument, and a coating (6; 27) on at least a portion (2; 24) of the conductive electrode body. The coating (6; 27) is a one-piece coating (6; 27) consisting of a first coating portion (15; 32) on the shank portion (5; 26) and a second coating portion (20; 37) on the cutting portion (3; 25), the coating (6; 27) preferably being provided by plastic injection molding onto the metal injection molded electrode body (2; 24).

Description

[Technical Field]

[0001] The present invention provides an electrosurgical electrode comprising: a conductive electrode body having a cutting portion configured to apply radio frequency electrical energy to tissue and an opposing shank portion configured to couple to an electrosurgical instrument; and a coating on at least a portion of the conductive electrode body; The present invention relates to an electrosurgical electrode comprising:

[0002] Electrosurgery involves using a single surgical instrument for both cutting and coagulation during surgery on a patient. This instrument can be an electrosurgical pencil (ESU) configured to use high frequency electrical energy to remove tissue and control bleeding. Today, most ESUs and many other types of electrosurgical instruments are completely disposable; only a few parts are replaceable or reusable.

[0003] A typical electrosurgical electrode has a non-stick coating applied to the cutting portion by a dipping or spraying process and a sleeve attached around a portion of the shank at the extension of the cutting portion. Some electrosurgical electrodes also include a heat-shrunk sleeve to cover the transition between the sleeve and the non-stick coating. For electrosurgical electrodes that do not have a non-stick coating in the energy transfer cutting region of the cutting portion, such cutting region must be masked before dipping or spraying, and the non-stick coating must be cured before the mask(s) can be removed. This conventional method of manufacturing electrosurgical electrodes is expensive because it requires many process steps and is time-consuming.

[0004] A primary aspect of the present invention is to provide an electrosurgical electrode that can be manufactured in fewer process steps than conventional electrosurgical electrodes.

[0005] In another aspect of the present invention, an electrosurgical electrode is provided that is cost-effective to manufacture.

[0006] Another aspect of the present invention provides an electrosurgical electrode that is simple and efficient to manufacture.

[0007] In another aspect of the present invention, an electrosurgical electrode is provided that effectively inhibits the accumulation of charred tissue on a patient's tissue during an electrosurgical procedure.

[0008] In another aspect of the present invention, an electrosurgical instrument, such as an electrosurgical pencil, is provided having a novel conductive electrode.

[0009] In accordance with the present invention, these and other aspects are achieved by a new and unique feature in that the coating is an integral coating consisting of a first coating portion on the shank portion and a second coating portion on the cutting portion of the conductive electrode body, the conductive electrode body being the substrate for said coating.

[0010] A significant difference between conventional electrosurgical electrodes and the electrosurgical electrode of the present invention is that the sleeve on the shank and the coating on the cutting portion are integrated into a one-piece coating that can be produced in a single application step. Thus, the second coating is an integral extension of the first coating, and the first coating of the present invention replaces the conventional sleeve on the shank, and the second coating replaces the conventional non-stick coating on the cutting portion of a conventional electrosurgical electrode. Also, there is no need to use an additional heat-shrink sleeve.

[0011] Thus, with respect to the electrosurgical electrodes of the present invention, the first coating portion of the one-piece coating functions as a sleeve and thus as an insulator. The first coating portion also provides protection and facilitates secure fixation of the electrosurgical electrode to the electrosurgical instrument. The second coating portion of the one-piece coating functions as a cutting area coating that resists eschar buildup, or at least allows for easy removal of such eschar if it does build up despite the potential non-stick properties of the coating.

[0012] The first covering portion may conveniently be integrally moulded with the second covering portion on the shank portion and the cutting portion, respectively, in an injection moulding process.

[0013] The first and second covering parts are preferably made of the same material, preferably a plastic material. In this case, the injection molding process can be a one-component injection molding process (1K) in which, for example, a plastic material or silicone rubber is applied to the relevant areas of the conductive electrode body in a single molding. However, within the scope of the present invention, a multi-component injection molding process (multi-K, for example, 2K or 3K) is not excluded. This process can be useful when two or more different materials are used in the integrated covering of the present invention (for example, to provide the layered structure of the integrated covering and / or to create the integrated covering), so that the first and second covering parts are different materials that are extended from each other but are fused to each other.

[0014] In principle, the conductive electrode body, which serves as the substrate for the coating, can be manufactured by a suitable casting process or by stamping, however in a preferred embodiment the conductive electrode body is manufactured by metal injection molding (MIM).

[0015] In MIM, fine metal powder is mixed with a binder and injected into a mold, in a manner similar to plastic injection molding. After molding, the binder is removed from the part, leaving a dense part that is sintered and shrinks. During sintering and subsequent shrinkage, microscopic changes occur in the surface structure of the substrate, improving the bonding of the coating to the substrate.

[0016] Metal injection molding is generally known to those skilled in the art and will not be discussed in further detail, but its advantages are clear: its use in the manufacture of conductive electrode bodies allows for mass production of finished electrosurgical electrodes with high precision, close tolerances, precise detail, and high coating bond strength.

[0017] Preferably, the integral coating comprises a fluoropolymer, such as polytetrafluoroethylene (PTFE), and / or silicone. The most preferred coating is entirely Teflon. (R) It is made of polytetrafluoroethylene, known by the trademark Teflon. (R) is chemically inert, durable and heat resistant up to 260°C, with excellent non-stick properties, providing the necessary high resistance to crust build-up and allowing it to be removed when required.

[0018] The cutting region of the cutting section may be free of the second coating to allow RF electrical energy to be applied to the patient's tissue through the cutting region to effect the necessary cutting during the electrosurgical procedure.

[0019] The shank portion may have a free end that is not covered by the first coating portion, the free end serving to establish electrical contact between the active conductive electrode body and a conductive circuit that conducts current from a generator to the conductive electrode body. When the shank portion is attached to an electrosurgical instrument, the first coating portion on the shank portion is conveniently sized and configured to securely mount the electrosurgical electrode within the mounting end of a handpiece of the electrosurgical instrument.

[0020] The coating can conveniently have both non-stick and insulating properties, since it functions as both a sleeve and a non-stick coating on the conductive electrode body.

[0021] The electrosurgical electrode may be a blade electrode, where the cutting portion is a blade and the cutting region is a free cutting edge. Such an embodiment of the electrosurgical electrode is particularly useful for both disposable and non-disposable electrosurgical pencils.

[0022] It should be emphasized that the present invention is not limited to blade electrodes. Any design of electrosurgical electrode is within the scope of the present invention, such as, for example, L-shaped, J-shaped, needle-shaped, loop electrodes, spatula electrodes, and ball electrodes. This list is not to be considered exhaustive or to limit the scope of the present invention.

[0023] The present invention further relates to methods of manufacturing electrosurgical electrodes, such as the electrosurgical electrodes described above.

[0024] The method comprises the steps of: a) manufacturing a conductive electrode body having a cutting portion and a shank portion; the manufacturing method is preferably metal injection molding; and b) overmolding a first covering portion on the shank portion and a second covering portion on the cutting portion (3; 25), wherein the first covering portion and the second covering portion are one-piece coverings, the first covering portion and the second covering portion being integrally molded with each other.

[0025] The integral coating in step b) is preferably made of Teflon as the plastic material. (R) It is made by 1K plastic injection molding using

[0026] The present invention further relates to an electrosurgical instrument including the electrosurgical electrode described above, which electrosurgical instrument is preferably an electrosurgical pencil.

[0027] The invention will now be explained in more detail with reference to the drawings. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a perspective exploded side view showing a first embodiment of an electrosurgical blade electrode according to the present invention; [Figure 2] The same is shown assembled. [Figure 3] FIG. 2 is a perspective exploded side view showing a second embodiment of an electrosurgical spatula electrode according to the present invention. [Figure 4] The same is shown assembled. [Figure 5] FIG. 2 is a cross-sectional view taken along line VV in FIG. [Figure 6] FIG. 2 is a cross-sectional view taken along line VI-VI in FIG. [Figure 7] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG.

[0029] The electrosurgical blade electrode 1 seen in Figures 1 and 2 comprises a cutting portion 3 in the form of a cutting blade 4 in the extension of an opposing shank portion 5, and an integral coating 6. The conductive electrode body 2 is manufactured by metal injection molding (MIM), after which the integral coating is applied as an overmold to the conductive electrode body 2 in a plastic injection molding process.

[0030] 8, the cutting blade 4 has an annular cutting edge 7 surrounding a central blade portion 8 that exposes opposed substantially flat sides 9, 10 for application of the integral coating 6. The shank portion 5 of the conductive electrode body 2 has an intermediate portion 11 opposite the free end 12, which tapers toward the cutting blade 4. The annular cutting edge 7 and the flat sides 9, 10 define opposed flat cavities 13, 14 adapted to receive a portion of the integral coating 6, as described below.

[0031] The one-piece covering 6 has a first covering portion 15 that forms a sleeve 16 on the shank portion 5. A free end 12 of the shank portion 5 is not covered by the sleeve 16 and serves to attach the electrosurgical blade electrode 1 to an electrosurgical instrument (not shown) for electrical contact therewith.

[0032] The sleeve 16 has a first sleeve end 17 facing the free end 12 of the shank portion 5, which extends into a main sleeve portion 18 and terminates in a second sleeve end 19, which constitutes a front sleeve portion.

[0033] As can also be seen in the cross-sectional view of FIG. 5, the first sleeve end 17 is configured as a male end fitting having a polygonal cross-section that mates with a complementary female end fitting on the handpiece of an electrosurgical instrument (not shown) to provide an anti-rotational connection to the electrosurgical instrument (not shown).

[0034] As can be seen in the cross-sectional view of Figure 6 in this embodiment of the electrosurgical electrode 1, the main sleeve portion 18 increases in cross-sectional area toward the second sleeve end 19, which tapers longitudinally toward the cutting blade 4 to cover the remainder of the shank portion 5 before the first coating portion 15 extends into a second coating portion 20 on the cutting blade 4, as can be seen in the cross-sectional view of Figure 7 (see cross-sectional view of Figure 8). The sleeve 16 is thus configured and adapted to be received inside the tapered front end of an electrosurgical instrument handpiece.

[0035] The second sleeve end 19 extends onto the opposing flat sides 9, 10 of the cutting blade 4 into a second partially branched covering portion 20. The second partially branched covering portion 20 is made up of opposing side covering portions 21, 22 configured to coat and cover opposing cavities 13, 14 of the central blade portion 8, thereby exposing the annular cutting edge 7.

[0036] 1 and 2 are side perspective views of a first embodiment of an electrosurgical electrode 1. In this embodiment, the electrosurgical electrode 1 is symmetrical about its longitudinal axis, with only one side of the cutting blade 4 and cavities 13, 14 visible. The presence of symmetrical features on the opposite flat side is indicated by corresponding reference numerals.

[0037] A second embodiment of an electrosurgical electrode is an electrosurgical spatula electrode 23, seen in Figures 3 and 4, which, like the blade electrode 1 seen in Figures 1 and 2, is manufactured by overmolding a substrate in the form of a conductive electrode body 24 made by metal injection molding with a plastic injection molding process. Essentially, the electrosurgical spatula electrode 23 is also an electrosurgical blade electrode, but with a relatively short cutting portion 25.

[0038] The electrosurgical spatula electrode 23 includes a second embodiment of a conductive electrode body 24 having a spatula-shaped cutting portion 25 on the extension of the opposite long shank portion 26, and a second embodiment of an integral coating 27 on a portion of the opposite long shank portion 26.

[0039] The spatula-shaped cutting portion 25 has an annular cutting edge 28 that defines a central spatula portion 29 for applying the integral coating 27. The shank portion 26 of the conductive electrode body 24 has an intermediate portion 30 opposite the free end 31, which tapers to the spatula-shaped cutting portion 25.

[0040] A second embodiment of the integral sheath 27 has a first sheath portion 32 forming a sleeve 33 on the shank portion 26, which first sheath portion 32 extends integrally with a second sheath portion 37 at the spatula-shaped cutting portion 25. A free end 31 of the shank portion 26 is not covered by the sleeve 33 and serves to attach the electrosurgical spatula electrode 23 to an electrosurgical instrument (not shown) for electrical contact therewith.

[0041] The sleeve 33 has a first sleeve end 34 facing the free end 31 of the shank portion 26, which extends to a main sleeve portion 35 and further to a second sleeve end 36 which terminates in a second covering portion 37.

[0042] The first sleeve end 34 is configured as a male end fitting having a polygonal cross section that mates with a complementary female end fitting on a handpiece of an electrosurgical instrument (not shown) to provide an anti-rotational connection to the electrosurgical instrument (not shown).

[0043] In the second embodiment of the electrosurgical electrode 23, the cross-sectional area of ​​the main sleeve portion 35 increases toward the second sleeve end 36, which tapers longitudinally along the second sleeve end 36, such that the second embodiment of the sleeve 33 is configured and adapted to be received within the tapered front end of an electrosurgical instrument handpiece. The second sleeve end 36 extends integrally with a second covering portion 37 that is partially bifurcated at the spatula-shaped cutting portion 25.

[0044] A partially branched second coating portion 37 is applied to the central spatula portion 29 of the spatula-shaped cutting portion 25, thereby exposing the annular cutting edge 28.

[0045] 3 and 4 are side perspective views of a second embodiment of an electrosurgical electrode 23. In the second embodiment, the electrosurgical electrode 23 is symmetrical about its longitudinal axis, with only one flat side of the spatula-shaped cutting portion 25 visible. The presence of symmetrical features on the opposite flat side is indicated by corresponding reference numerals.

[0046] Both the cutting blade 4 of the electrosurgical blade electrode 1 and the spatula-shaped cutting portion 25 of the electrosurgical spatula electrode 23 have through holes 38 available for better adhesion of the second coating portion 20; 37 onto the cutting blade 4 and spatula-shaped cutting portion 25, respectively, in addition to the integral coating being fusion-bonded to the surface of the conductive electrode body 2; 24, providing a mechanical bond to the opposite portion of the branched second coating portion of the integral coating as the material of the second coating portion flows into the through holes 38.

[0047] Figures 5-8 are cross-sectional views along the length of the first embodiment of the electrosurgical electrode 1 seen in Figure 1, showing that the integral coating varies in thickness and profile along the length of the conductive electrode body 2. In particular, Figure 8 shows that the cutting edge 7 is exposed from the second coating portion 20.

Claims

1. An electrosurgical electrode (1;23), a conductive electrode body (2; 24) having a cutting portion (3; 25) configured to apply RF electrical energy to tissue and an opposing shank portion (5; 26) configured to couple to an electrosurgical instrument; a coating (6; 27) on at least a portion of said conductive electrode body (2; 24), An electrosurgical electrode (1; 23) comprising: The coating (6; 27) a first covering portion (15; 32) on said shank portion (5; 26), and a second covering part (20; 37) on said cutting part (3; 25); Electrosurgical electrode (1; 23), characterized in that it is an integral covering (6; 27) consisting of

2. 2. The electrosurgical electrode (1; 23) according to claim 1, characterized in that the first covering portion (15; 32) is integrally molded with the second covering portion (20; 37) on the shank portion (5; 26) and on the cutting portion (3; 25), respectively, in an injection molding process.

3. 3. An electrosurgical electrode (1; 23) according to claim 1 or 2, characterized in that the first covering part (15; 32) and the second covering part (20; 37) are made of the same material, preferably a plastic material.

4. Electrosurgical electrode (1; 23) according to any one of claims 1 to 3, characterized in that the conductive electrode body (2; 24) is made by metal injection molding.

5. 5. An electrosurgical electrode (1; 23) according to any one of claims 1 to 4, characterized in that the coating (6; 27) comprises a fluoropolymer, preferably polytetrafluoroethylene (PTFE), and / or silicone, more preferably the coating (6; 27) is made entirely of polytetrafluoroethylene.

6. 6. An electrosurgical electrode (1; 23) according to any one of claims 1 to 5, characterized in that the cutting region (7; 28) of the cutting part (3; 25) is free of the second covering part (20; 37).

7. 7. An electrosurgical electrode (1; 23) according to any one of claims 1 to 6, characterized in that the shank portion (5; 26) has a free end (12; 31) that is not covered by the first covering portion (15; 32).

8. 8. An electrosurgical electrode (1; 23) according to any one of claims 1 to 7, characterized in that the first covering portion (15; 32) on the shank portion (5; 26) is configured to securely mount the electrosurgical electrode (1; 23) within a mounting end of an electrosurgical instrument.

9. A method for manufacturing an electrosurgical electrode (1; 23), comprising the steps of: a) manufacturing a conductive electrode body (2) having a cutting portion (3; 25) and a shank portion (5; 26); the manufacturing method is preferably metal injection molding; and b) overmolding a first covering portion (15; 32) on the shank portion (5; 26) and a second covering portion (20; 37) on the cutting portion (3; 25), wherein the first covering portion (15; 32) and the second covering portion (20; 37) are one-piece coverings (6; 27) and the first covering portion (15; 32) and the second covering portion (20; 37) are integrally molded with each other; preferably, the overmolding process is plastic injection molding. A method comprising:

10. Electrosurgical instrument comprising an electrosurgical electrode (1; 23) according to any one of claims 1 to 8.

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