Embodiments of the present disclosure described herein relate to surgical devices, and in particular to a shaver arrangement for a surgical instrument and an end effector for an electrosurgical instrument.
Many shavers, for example, arthroscopic shavers, have blades with teeth on either the inner blade, outer blade, or both. Typically, the more teeth, and the sharper the teeth, the more aggressive the blade is assumed to be during clinical use. Very aggressive blades must also be carefully positioned within the clinical joint space to avoid any collateral tissue damage to healthy tissue. In traditional arthroscopic shavers, there is generally only one shave window with teeth, and therefore the opposite side of the end effector is smooth. This allows surgeons to slide over healthy tissue with the smooth side, while keeping the sharp teeth away from healthy tissue when accessing tight spaces.
In a dual sided RF shaver construction, both sides of the tip have a function, and therefore neither side is perfectly smooth. Therefore, a fundamental conflict exists for an ultra-aggressive blade. During shaver use, the blade should be as aggressive as a typical toothed outer blade, but when the user is operating the RF side of the active tip, the teeth should not cause any collateral tissue damage to healthy tissue when the blade window is closed and the shaver is stationary.
Typical inner and outer teeth profiles for ultra-aggressive shaver shown in
The present disclosure addresses the above problem, by providing a shaver arrangement for a surgical instrument wherein the outer profile of the cutting blade located on the outer tubular member is smooth, such that it greatly reduces the likelihood of the cutting blade snagging or interacting with non-target tissue (i.e. causing collateral damage). In other words, with reference to the prior art
Embodiments of the present disclosure provide a shaver arrangement for a surgical instrument which reduces the likelihood of collateral damage to surrounding non-target tissue. The arrangement does not have tissue engagement cutting points on the outer profile of the cutting blade of the arrangement, thereby reducing the likelihood of collateral damage when manoeuvring the surgical instrument as tissue is less likely to be inadvertently caught by the tissue cutting points.
In view of the above, from a first aspect, the present disclosure relates to a shaver arrangement for a surgical instrument, the shaver arrangement comprising an outer member and a cutting blade at a distal end thereof. The cutting blade being serrated to form a plurality of teeth, each of the teeth forming one or more tissue engaging cutting points. The one or more tissue engaging cutting points being arranged in use to snag and/or cut tissue. The tissue engaging cutting points being located inwardly from the outer member such that there are no tissue engaging cutting points capable in use of snagging and/or cutting tissue located on or outwards of an outer surface of the outer member. Several advantages are obtained from embodiments according to the above described aspect. For example, the tissue engaging cutting points are arranged such that they interact only with tissue to be treated, not healthy surrounding tissue.
In some embodiments, each of the plurality of teeth has a tooth peak, and the tooth peak forms one of the one or more tissue engaging cutting points.
In some embodiments, there are no tissue engaging cutting points located outwards of an inner surface of the outer member.
This is advantageous as by only having tissue engaging cutting points located outwards of an inner surface of the outer member, the chance of the tissue engaging cutting points catching healthy surrounding tissue and causing collateral damage is greatly reduced.
In some embodiments, the cutting blade has a chamfered edge and/or radius edge. This results in an arrangement where the tissue engaging cutting points are located inwards from the outer member such that there are no tissue engaging cutting points capable in use of snagging and/or cutting tissue located on or outwards of an outer surface of the outer member. The chamfered edge and/or radius edge may connect an outer surface of the cutting blade to an inner surface of the cutting blade. The chamfered edge and/or radius edge may be angled such that the inner surface of the cutting blade extends further than the outer surface of the cutting blade. The one or more tissue engaging cutting points may be located at the inner surface of the cutting blade. The chamfered edge and/or radius edge may be angled at an angle between 10 and 60 degrees with respect to an axial plane to a longitudinal plane of the shaver arrangement. The angle may be between 30 and 50 degrees.
In some embodiments, the shaver arrangement is a rotary shaver arrangement, the outer member is an outer tubular member with a cutting window at the distal end thereof, the cutting window has at least one sharpened edge to form the cutting blade, and the tissue engaging cutting points are located radially inwards from the outer tubular member such that there are no tissue engaging cutting points capable in use of snagging and/or cutting tissue located on or outwards of an outer circumference of the outer tubular member.
In some embodiments, the outer tubular member has a central passageway and the cutting window is a first cutting window, and the arrangement further comprises an inner tubular member rotatably mounted in the central passageway of the outer tubular member and providing a central suction lumen, the inner tubular member having a second cutting window at the distal end thereof such that the first and second cutting windows align when the inner tubular member is rotated to a first position. The arrangement may be such that, when in use, rotation of the inner tubular member within the outer tubular member causes a tissue cutting action of the cutting blade interacting with the second cutting window.
In some embodiments, the shaver arrangement of any of the above embodiments is incorporated into an end effector for an electrosurgical instrument, the end effector additionally comprising an RF arrangement including an active electrode.
From a second aspect, the present disclosure relates to an end effector for an electrosurgical instrument, the end effector comprising an RF arrangement including an active electrode; and a shaver arrangement comprising an outer member and a cutting blade at a distal end thereof. The cutting blade is arranged to have one or more tissue engaging cutting points, the one or more tissue engaging cutting points being arranged in use to snag and/or cut tissue, the tissue engaging cutting points being located inwardly from the outer member such that there are no tissue engaging cutting points capable in use of snagging and/or cutting tissue located on or outwards of an outer surface of the outer member.
The above embodiments relating to the first aspect may equally apply to the second aspect.
In some embodiments, the shaver arrangement is such that, when the RF arrangement is in use, there is a reduced likelihood of the shaver arrangement engaging with tissue. This is advantageous as, for example, for dual sided RF shavers, the RF arrangement and the shaver arrangement may be located at different circumferential locations around the end effector's tubular members (e.g. on opposite sides), and so when the RF arrangement is being used to treat tissue and the shaver arrangement is not in use, the movement of the end effector does not cause tissue engagement points of the shaver arrangement to catch on non-target tissue and cause collateral damage.
In some embodiments, the cutting blade is serrated to form a plurality of teeth, each of the plurality of teeth forming one of the one or more tissue engaging cutting points. Each of the plurality of teeth may have a tooth peak, and the tooth peak may form one of the one or more tissue engaging cutting points.
From a third aspect, the present disclosure relates to an electrosurgical instrument comprising: an end effector according to the last embodiment of the first aspect described above, or any embodiment of the second aspect described above; and an operative shaft having RF electrical connections operably connected to the active electrode, and drive componentry operably connected to the shaver arrangement to drive the shaver arrangement to operate in use.
From a fourth aspect, the present disclosure relates to an electrosurgical system, comprising: an RF electrosurgical generator; and an electrosurgical instrument according to the third aspect, the arrangement being such that in use the RF electrosurgical generator supplies an RF coagulation or ablation signal via the RF electrical connections to the active electrode.
Embodiments of the invention will now be further described by way of example only and with reference to the accompanying drawings, wherein:
Overview
Embodiments of the present disclosure modify and improve upon prior art designs of shaver arrangements by smoothing the outer profile of the sharpened edge used to cut tissue. This sharpened edge is located within/on the outer member of the shaver arrangement, and in use, movement of an inner member with respect to the outer member causes a tissue cutting action of the inner surface of the cutting blade interacting with the inner member. There is no need for the outer surface of the sharpened edge to be a tissue engaging point, and as described above, by having tissue engaging points on the outer surface of the sharpened edge, there is a significant possibility of collateral damage to nearby tissue.
Embodiments of the present disclosure provide a shaver arrangement wherein the sharpened edge/cutting blade has a smooth outer profile to prevent tissue catching on the outer surfaces of the blade. In other words, the outer profile of the cutting blade does not have any tissue engaging cutting points. Only the inner profile of the cutting blade has tissue engaging cutting points.
The smooth outer profile may be in the form of a chamfered and/or radius edge. In the case of a chamfered edge, the chamfer is in the axial plane to the shaver rotational plane. The inside edge shearing tooth (the tissue engaging point on the inner surface of the outer tubular member) is still present, and the inner cutting blade geometry remains unchanged as this is hidden during RF activation. However, the outer tooth that presents more of a collateral damage risk during opposite sided RF use is removed from the geometry using a chamfer/blend to the outer surface of the blade. The resulting geometry with a closed shave window is a smoother profile, less likely to damage surrounding tissue during opposite sided RF tip use.
Various aspects and details of these principal components will be described below by way of example with reference to
The Electrosurgical System
Referring to the drawings,
The Electrosurgical Instrument
The instrument 3 includes a proximal handle portion 3a, a shaft 3b extending in a distal direction away from the proximal handle portion, and a distal end effector assembly 3c at the distal end of the shaft 3b. A power connection cord 4 connects the instrument to the RF generator 1. The instrument may further be provided with activation buttons (not shown), to allow the surgeon operator to activate either the mechanical cutting function of the end effector, or the electrosurgical functions of the end effector, which typically comprise coagulation or ablation.
The teeth 344 have a slanted outer profile. The slanted outer profile of the teeth 344 is created by adding a chamfered/bevelled/radius edge to the outer tooth profile only. The chamfered edge is in the axial plane to the shaver rotational plane. The resulting geometry when the blade/cutting window is closed is a smoother profile, resulting in a lower likelihood of damage to surrounding tissue during use of the RF side 310. However, it will be appreciated that having a serrated edge with a plurality of teeth is not a requirement to implement certain embodiments of the present invention. The slanted outer profile concept may be similarly applied to non-serrated sharpened edges. For example, the sharpened edge may look like
The inner tubular member 330 is rotatably disposed inside of the outer tubular member 340 such that the surgical instrument 3 cuts tissue by rotating the inner tubular member 330 within the outer tubular member 340 while a vacuum is applied through the lumen of the inner tubular member 330 to draw the tissue into the cutting windows and sever the tissue by rotation of the inner tubular member.
The RF side 320 of the electrosurgical instrument 3 comprises an electrode assembly comprising an active electrode for tissue treatment (“active tip”) 322 received in a ceramic insulator 324. The active tip 322 is provided with projections 326 to concentrate the electric field at those locations. The projections 326 also serve to create a small separation between the planar surface of the active electrode 322 and the tissue to be treated. This allows conductive fluid to circulate over the planar surface, and avoids overheating of the electrode or the tissue. The active tip 322 of the instrument may be provided with a suction aperture (not shown), which is the opening to a lumen within an inner tubular member 330.
In more detail, when the RF side 320 is to be used as a suction tool by applying a vacuum through the lumen within the inner tubular member 330, the inner tubular member 330 (which acts as a cutting blade) is stopped from rotating and the cutting windows of the inner and outer tubular members are misaligned with each other, i.e. closing the cutting windows, (as is the case in
In contrast, when the shaver side 310 is in use for a cutting operation, suction may flow via through the cutting windows to the lumen.
The inner and outer tubular members 330 and 340 may be made from stainless steel. Stainless steel is a good option as it is easy to bond to the steel cuttings tips of inner and outer tubular members, which act as the RF return, and due to the blade properties of hardened steel.
Embodiments of the present disclosure (
It will be apparent to the skilled person that although one advantageous use of the invention is in a dual-sided RF shaver, the invention may also be applied to instruments without RF capabilities, for example, reciprocating shavers, rotary shavers and/or arthroscopic shavers.
From one aspect, the shaver arrangement does not have to have RF capabilities and is formed of a cutting blade being serrated to form a plurality of teeth. Each of the teeth form one or more tissue engaging cutting points. The one or more tissue engaging cutting points are arranged in use to snag and/or cut tissue. However, the tissue engaging cutting points are located inwardly from the outer member which the cutting blade is located on such that there are no tissue engaging cutting points capable in use of snagging and/or cutting tissue located on or outwards of an outer surface of the outer member.
From a second aspect, there is an end effector which has an RF arrangement and a shaver arrangement. The shaver arrangement does not need to have a cutting blade being serrated to form a plurality of teeth. However, the cutting blade is arranged to have one or more tissue engaging cutting points, the one or more tissue engaging cutting points being arranged in use to snag and/or cut tissue, the tissue engaging cutting points being located inwardly from the outer member such that there are no tissue engaging cutting points capable in use of snagging and/or cutting tissue located on or outwards of an outer surface of the outer member.
Therefore, there are predominantly two aspects of the invention. Firstly, a shaver arrangement with teeth, the teeth arranged so that they do not snag and/or cut non-target tissue. Secondly, an end effector which has RF capabilities and a shaver arrangement with a cutting blade arranged such that it does not snag and/or cut non-target tissue.
Various modifications whether by way of addition, deletion, or substitution of features may be made to above described embodiment to provide further embodiments, any and all of which are intended to be encompassed by the appended claims.
Number | Date | Country | |
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63241767 | Sep 2021 | US |