GB2617395A

GB2617395A - Robotic surgical instrument

Info

Publication number: GB2617395A
Application number: GB2205188.2A
Authority: GB
Inventors: Haig Fiona
Original assignee: CMR Surgical Ltd
Current assignee: CMR Surgical Ltd
Priority date: 2022-04-08
Filing date: 2022-04-08
Publication date: 2023-10-11
Also published as: GB202205188D0; DE202023101708U1

Abstract

A robotic surgical instrument 400 comprising an end effector with first 404-1 and second 404-2 effector elements. A first region 401 of the end effector is for grasping tissue, the first and/or second effector elements comprising tissue grasping protrusions 406. The first region may comprise a second textured region on the inner surface and a third textured region 412 on the outer surface of the elements. The protrusions may be received in recesses in the opposing effector element or retract into their respective inner surface 420. A second region 402 is configured for gripping a needle, the inner surface of the first and/or second end effector elements comprising a needle-gripping textured area 408. A third region 403 is configured for cutting, the first and/or second end effector element comprising a blade 410 that may be retractable, have a retractable blade guard or be energised by an electrosurgical generator.

Description

ROBOTIC SURGICAL INSTRUMENT

FIELD

The present disclosure relates to a robotic surgical instrument. In particular, the present disclosure relates to a multi-functional robotic surgical instrument for use during a minimally invasive suturing process.

BACKGROUND

It is known to use robots for assisting and performing surgery. Figure 1 illustrates an example robotic surgical system 100, which comprises two robot arms 102 for manipulating tissue. Each robot arm 102 consists of a base 108. The base supports the robot arm, and is itself attached rigidly to, for example, the operating theatre floor, the operating theatre ceiling or a trolley. Each robot arm 102 is articulated by means of multiple flexible joints 103 along its length, which are used to locate a surgical instrument 200 in a desired location relative to the patient 101. The surgical instrument 200 could, for example, be a cutting or grasping device. A surgical instrument 200 is attached to the distal end of each robot arm 102. The surgical instrument 200 is positioned within the body of the patient 101 via a port 107 so as to access a surgical site. At its distal end the instrument comprises an end effector 204 for performing aspects of a medical procedure. This type of medical procedure is often referred to as a minimally invasive surgical procedure.

The configuration of each robot arm 102 may be remotely controlled in response to inputs received at a remote surgeon console (not shown in Figure 1 for simplicity). A surgeon may provide inputs to the remote console. The remote surgeon console may comprise one or more surgeon input devices. For example, these may take the form of one or more hand controllers and/or foot pedals. The surgeon may remotely control one of the two robot arms 102 with each of their hands. A video feed of the surgical site may be captured by an endoscope, often attached to a further robot arm (not shown in Figure 1 for simplicity), and displayed at the remote surgeon console.

Figure 2 illustrates a typical robotic surgical instrument 200 for use in a minimally invasive surgical procedure. The robotic surgical instrument comprises a proximal base 201 by means of which the surgical instrument connects to the robot arm. A shaft 202 extends between base 201 and an articulation 203. Articulation 203 connects the shaft to an end effector 204. In Figure 2, a pair of serrated jaws are illustrated as the end effector 204. The articulation 203 permits the end effector 204 to move relative to the shaft 202. It is desirable for at least two degrees of freedom to be provided to the motion of the end effector 204 by means of the articulation.

Figure 3 illustrates a typical articulation 203 of a robotic surgical instrument 200. The end effector 204 comprises two end effector elements 204-1 and 204-2. The end effector 204 is permitted to move relative to shaft 202 by means of a pitch joint 203-1 and two yaw joints 203-2. Pitch joint 203-1 enables the end effector 204 as a whole to rotate about a pitch axis. Yaw joints 203-2 enable each end effector element 204-1, 204-2 to rotate about a yaw axis. In the perspective view shown in Figure 3, only one of the two yaw joints 203-2 is visible -yaw joint 203-2a, which permits end effector element 204-1 to rotate about the yaw axis. In Figure 3, the joints are driven by cables. It is to be understood that Figure 3 shows just one example of a known articulation, and that the various other suitable articulations could be used to permit the end effector zo 204 to move relative to the shaft 202.

Typically, robotic surgical instruments are highly optimised for performing one specific task. For example, the end effector of a robotic surgical instrument may be optimised for gripping a suturing needle. Typical minimally invasive surgical procedures often require the surgeon to perform a number of different tasks (e.g. a series of different tasks). Hence, during a typical minimally invasive surgical procedure, the surgeon often utilises a number of different robotic surgical instruments. The number of different robotic surgical instruments used during a minimally invasive surgical procedure often exceeds the number of robot arms available in a robotic surgical system. Hence, on any one robot arm, one instrument is often exchanged for another a number of times.

SUMMARY OF THE INVENTION

According to a first aspect of the invention there is provided a robotic surgical instrument comprising an end effector, the end effector comprising: a first end effector element and a second end effector element, each of the first and second end effector elements comprising an inner surface that faces a respective inner surface of the other end effector element when the end effector is closed; a first region configured for grasping tissue, wherein, in the first region, the first end effector element and/or the second end effector element comprise one or more primary protrusions configured for grasping tissue; a second region configured for gripping a needle, wherein, in the second region, the inner surface of the first end effector element and/or the second end effector element comprises a first textured area configured for gripping a needle; and a third region configured for cutting, wherein, in the third region, the first end effector element and/or the second end effector element comprises a blade configured for cutting.

The first region may be a distal region of the end effector, the second region may be an intermediate region of the end effector, and the third region may be a proximal region of the end effector.

The robotic surgical instrument may comprise a shaft and an articulation connecting the shaft to the end effector, the shaft being proximal to the end effector.

The structure of the first region may be different to the structure of the second region.

The first region may not be configured for gripping a needle and the first region may not be configured for cutting.

The second region may not be configured for grasping tissue and second region may not be configured for cutting.

The third region may not be configured for grasping tissue and third region may not be configured for gripping a needle In the first region, in at least one configuration of the end effector, each of the one or more primary protrusions comprised by the first end effector element or the second end effector element may protrude towards the inner surface of the other end effector element.

In the first region, the one or more primary protrusions may not protrude beyond the outer profile of the end effector when the end effector is closed.

When the end effector is closed, each of the one or more primary protrusions may be received in respective recesses provided in the other end effector element.

The first end effector element may comprise a first primary protrusion and the second end effector element may comprise a first recess for receiving the first primary protrusion when the end effector is closed, and the second end effector element may comprise a second primary protrusion and the first end effector element may comprise a second recess for receiving the second primary protrusion when the end effector is closed.

Each of the one or more primary protrusions may be retractable into the inner surface of their respective end effector element.

In the first region, the one or more primary protrusions may define a blunt portion of the outer profile of the end effector when the end effector is closed.

In the first region, the one or more primary protrusions may be angled towards the proximal end of the end effector.

In the first region, the one or more primary protrusions may have a tapered form.

In the second region, the first textured area may comprise protrusions that protrude, from their respective inner surface, a lesser distance than the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element.

In the first region, the inner surface of the first end effector element and/or the second end effector element may comprise a second textured area for gripping tissue.

The second textured area may comprise secondary protrusions that protrude, from their respective inner surface, a lesser distance than the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element.

In the first region, an outer surface of the first end effector element and/or the second end effector element may comprise a third textured area for gripping tissue.

The third textured area may comprise tertiary protrusions that protrude, from their respective outer surface, a lesser distance than the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element.

The blade may be retractable. The end effector may comprise a retractable blade guard.

zo In use, the blade may be energisable by an electrosurgical generator.

The first end effector element or the second end effector element may comprise a blade configured for cutting against the inner surface of the other end effector element.

Both the first end effector element and the second end effector element may comprise a respective blade configured for cutting against the blade of the other end effector element.

According to a second aspect of the invention there is provided a robotic surgical instrument comprising an end effector, the end effector comprising: a first region comprising one or more protrusions configured for grasping tissue; a second region comprising a textured surface configured for gripping a needle; and a third region comprising a blade configured for cutting.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described by way of example with reference to the accompanying drawings. In the drawings: Figure 1 illustrates an example robotic surgical system; Figure 2 illustrates a typical robotic surgical instrument; Figure 3 illustrates a typical articulation of a robotic surgical instrument; Figures 4A and 4B schematically illustrate a first example robotic surgical instrument according to the principles described herein.

Figure 4C schematically illustrates a variation on the first example robotic surgical instrument according to the principles described herein.

Figures 5A and 5B schematically illustrate a second example robotic surgical instrument according to the principles described herein.

DETAILED DESCRIPTION OF THE DRAWINGS

The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art.

The general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

As described herein, typical minimally invasive surgical procedures often require a surgeon to perform a number of different tasks. One example of such a procedure is the minimally invasive suturing process (e.g. "suturing"). The minimally invasive suturing process is one of the most performed minimally invasive surgical procedures -as it is used in a vast number of different surgeries.

To perform suturing, a surgeon uses robotic surgical instruments (e.g. "instruments") to: (i) apply tension to the tissue to be sutured (e.g. by stretching a portion of tissue, or by pinching and lifting a portion of tissue); (ii) drive a suturing needle threaded with suture material through the tensioned tissue; and (iii) cut the stitch from the remainder of the suture material. The surgeon would typically repeat tasks (i), (ii) and (iii) numerous times so as to insert multiple stitches in order to close an incision.

As described herein, robotic surgical instruments are typically highly optimised for performing one specific task. Hence, in order to perform suturing, a surgeon may typically use three different types of specialised robotic surgical instruments, for example: (i) forceps so as to tension the tissue to be sutured; (ii) needle holders to grip the suturing needle; and (iii) scissors to cut the stitch from the remainder of the suture material.

As described herein, a typical robotic surgical system may comprise two robot arms for manipulating tissue (e.g. as shown in Figure 1). A video feed of the surgical site may be captured by an endoscope, often attached to a further robot arm (not shown in Figure 1 for simplicity). In use, the surgeon may remotely control one robot arm for manipulating tissue with each of their hands. This means that, at any one time, only two of the three different types of specialised robotic surgical instruments used to perform minimally invasive suturing may be positioned and controlled within the body of the patient. As a result, the instruments attached to the robot arms are frequently changed in order to perform suturing. For example, to insert a stitch, the surgeon may use forceps controlled by one hand to tension the tissue to be sutured, and a first needle holder controlled by their other hand to drive a suturing needle threaded with suture material through the tensioned tissue. The procedure may then be paused whilst the forceps are removed from the patient and replaced with a second needle holder. The procedure can then be resumed so that the surgeon can grip, using the second needle holder, the end of the needle that has passed through the tissue, and then release the other end of the needle from the first needle holder. The procedure may then be paused again whilst the first needle holder is removed from the patient and replaced with scissors. The procedure can then be resumed so that the surgeon can cut the stitch from the remainder of the suture material. Were the surgeon to want to insert a further stitch, the procedure may then be paused again whilst the scissors are changed for forceps, so that the process can be repeated.

Each instrument change takes time, and so increases the duration of the minimally invasive suturing process. It is generally desirable to minimise the duration of a surgical procedure, e.g. so as to minimise the amount of time that the patient is sedated under anaesthetic, reduce the fatigue experienced by the surgeon performing the surgery, and even increase the number of surgeries that a surgeon can perform in a given time frame.

In addition, the current trend in instrument sterilisation regulation is to increasingly limit the amount of protein that can remain on a re-usable instrument after a cleaning cycle. This means that the use of disposable (e.g. single-use) robotic surgical instruments is expected to increase. For this reason, it is desirable to reduce as far as possible the number of robotic surgical instruments used during a surgical procedure, e.g. so as to decrease the cost associated with performing a surgical procedure (i.e. as each single-use instrument used has an associated cost), and reduce the amount of medical waste (i.e. in the form of single-use instruments) produced during a surgical procedure.

Therefore, sometimes, rather than change an instrument, a surgeon may attempt to use an instrument that is highly optimised for performing one task for performing a different task for which it is not optimised. For example, a surgeon may attempt to use a needle holder to apply tension to the tissue to be sutured by stretching a portion of tissue, but a needle holder is not configured for performing this task. Using instruments to perform tasks for which they are not intended can cause problems and/or raise safety concerns.

To address one or more of the problems identified in the preceding paragraphs, examples of a multi-functional robotic surgical instrument for use during a minimally invasive suturing process are described herein with reference to Figures 4A to 4C, 5A and 5B.

Figures 4A and 4B schematically illustrate a first example robotic surgical instrument 400 according to the principles described herein. The instrument 400 comprises an end effector 404. In Figures 4A and 4B, for simplicity and ease of illustration, only the end effector 404 of said robotic surgical instrument 400 is shown. It is to be understood that the instrument may also comprise a shaft and an articulation connecting the shaft to the end effector. For example, the shaft and articulation may be of the type described with reference to Figures 2 and 3, or of any other suitable type.

As shown in Figures 4A and 4B, end effector 404 comprises a first end effector element 404-1 and a second end effector element 404-2. Joints 203-2a and 203-2b enable end effector elements 404-1 and 404-2, respectively, to rotate about an axis.

In an example, joints 203-2 may be referred to as yaw joints, and the axis may be a yaw axis. In other words, the first and second end effector elements 404-1, 404-2 are rotatably mounted with respect to one another. End effector elements 404-1 and 4042 may rotate independently about the axis. In other words, one end effector element may rotate whilst the other end effector element remains stationary, and vice versa. In the instrument shown in Figures 4A and 4B, the first and second end effector elements 404-1, 404-2 are independently rotatable about a common axis. It is to be understood that this need not be the case. In other examples the first and second end effector elements 404-1, 404-2 may be rotatable about different axes and/or may not be independently rotatable.

Each of the first and second end effector elements 404-1, 404-2 comprise an inner surface 420 that faces a respective inner surface 420 of the other end effector element when the end effector 404 is closed.

End effector 404 comprises a first region 401 configured for grasping tissue, a second region 402 configured for gripping a needle and a third region 403 configured for cutting (e.g. cutting a suture). Where it is stated herein that an end effector region is configured for a purpose, the stated purpose is to be understood as the primary or intended purpose of that end effector region. In Figures 4A and 4B, the first region 401 is a distal region of the end effector 404, the second region 402 is an intermediate region of the end effector 404, and the third region 403 is a proximal region of the end effector 404. The first, second and third regions do not overlap with each other. In other words, the first and second regions (401 and 402) do not overlap with each other, the first and third regions (401 and 403) do not overlap with each other, and the second and third regions (402 and 403) do not overlap with each other. It is to be understood that, in medical robotics, the term "proximal" is typically used to refer to positions relatively closer to the base of the robot and the term "distal" is typically used to refer to positions relatively closer to the surgical site (i.e. further away from the base of the robot). This is a preferable arrangement of the end effector regions relative to one another, but it is to be understood that other arrangements could alternatively be used. It is to be understood that the first, second and third regions described herein need not be separated by linear boundaries as shown in Figures 4A and 4B for simplicity. For example, the textured area 408 of the second region 402 may extend more distally (not shown in Figure 4A) between the primary protrusions 406a, 406b and respective recesses 405a, 405b of the first region 401, such that the boundary between the first and second regions is non-linear (e.g. curved).

In Figures 4A and 4B, in the first region 401, the first end effector element 404-1 and the second end effector element 404-2 each comprise a primary protrusion 406 configured for grasping tissue. More generally, in the first region, the first end effector element and/or the second end effector element may comprise one or more primary protrusions configured for grasping tissue. That is, in other examples not shown in the Figures: one of the end effector elements may comprise one or more primary protrusions whilst the other end effector element does not comprise any primary protrusions; one of the end effector elements may comprise one primary protrusion whilst the other end effector element comprises a plurality of primary protrusions; or both of the end effector elements may comprise a plurality of primary protrusions. The primary protrusion(s) comprised by the first and/or second end effector elements could be arranged in any suitable manner.

In Figures 4A and 43, the primary protrusions 406 protrude from the inner surfaces 420 of each of the first end effector element 404-1 and the second end effector element 404-2, respectively. In at least one configuration of the end effector 404 (e.g. a partially open configuration as shown in Figures 4A and 4B), each of the one or more primary protrusions comprised by the first end effector element 404-1 or the second end effector element 404-2 protrudes towards the inner surface 420 of the other end effector element. In Figures 4A and 4B, for example, each of the primary protrusions 406 may protrude by between 0.3mm and 4mm from its respective inner surface 420 -e.g. illustrated as dimension "x" in Figure 4B. More generally, in this example, each of the one or more primary protrusions could be said to protrude by between 0.3mm and 4mm from a plane that is substantially defined by the inner surface, in the second region, of its respective end effector element -e.g., again, illustrated as dimension "x" in Figure 4B. It is to be understood that the primary protrusion distance of between 0.3mm and 4mm provided herein is by way of example only. Other suitable primary protrusion distances could be used. A suitable primary protrusion distance can be selected in dependence on the size of the end effector elements (e.g. generally speaking, larger end effector elements may comprise larger primary protrusions).

Each primary protrusion may have a tapered form. That is, a primary protrusion may taper (e.g. progressively reduce in cross-sectional area) from a base to a tip. A primary protrusion may be a cone (e.g. as illustrated in Figure 4A), a pyramid (e.g. having a polygonal base), or any other suitable three-dimensional shape. For example, Figure 4C illustrates a variation on the first example robotic surgical instrument, in which the primary protrusions 416 are angled and/or curved towards the proximal end of the end effector 404. In other words, primary protrusions 416 could be said to resemble snake's teeth. Primary protrusions 416 may advantageously provide increased levels of grip when tensioning tissue by pulling grasped tissue in directions similar to the direction in which the primary protrusions 416 are angled and/or curved.

The primary protrusions may not protrude beyond the outer profile of the end effector when the end effector is closed. This is advantageous as it facilitates the insertion of the instrument 400 into, and subsequent removal of the instrument from, a patient without causing unintentional damage to the patient's tissues. This can be achieved in a number of different ways. In the example shown in Figure 4A, each of the primary protrusions 406 can be received in respective recesses 405 provided in the other end effector element when the end effector is closed. That is, in Figure 4A, the first end effector element 404-1 comprises a first primary protrusion 406a and the second end effector element 404-2 comprises a first recess 405a for receiving the first primary protrusion 406a when the end effector 404 is closed. The second end effector element 404-2 comprises a second primary protrusion 406b and the first end effector element 404-1 comprises a second recess 405b (not visible in Figure 4A) for receiving the second primary protrusion 406b when the end effector 404 is closed. Each primary protrusion may be whole or partly received in its respective recess. In another example, the one or more primary protrusions may additionally or alternatively be retractable into the inner surface 420 of their respective end effector elements. Each primary protrusion may be whole or partly retractable in its respective end effector element. For example, a resistive element (e.g. a spring) may urge a primary protrusion towards a position in which it protrudes from its end effector element. An appropriate resistive force to be exerted by the resistive element may be determined so as not to be exceeded by the forces experienced during tissue grasping such that the primary protrusion remains in its protruded position, but that is capable of being exceeded by the end effector closing mechanism such that the protrusions can be retracted into their respective end effector element when the end effector is closed for insertion into/removal from the patient.

By way of one or more of the features described herein, the primary protrusions are configured to grasp tissue. A surgeon could use the instrument 400 to tension tissue during suturing in a number of different ways. For example, the surgeon could gradually close the end effector such that a portion of tissue is pinched between the primary protrusions 406. That portion of tissue can then be "lifted" (e.g. pulled away from its natural position) so as to apply tension to the surrounding tissues. In another example, the surgeon could gradually open the end effector (e.g. to an opening angle of greater than 90°) such that primary protrusions 406 each engage a portion of tissue, and then stretch those portions of tissue apart as the end effector continues to open.

Optionally, in the first region 401, the inner surface 420 of the first end effector element 404-1 and/or the second end effector element 404-2 may comprise a textured area (not shown in the Figures) for gripping tissue. Said textured area may be positioned between the primary protrusions, may partially or wholly surround the primary protrusions, and/or may partially or wholly surround the recesses used for receiving each of the primary protrusions when the end effector is closed. Said textured area may be configured to aid the primary protrusions in gripping tissue (e.g. in particular when the end effector is being closed so as to pinch a portion of tissue). Said textured area may comprise secondary protrusions that protrude, from their respective inner surface, a lesser distance than the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element. In an example, the secondary protrusions may protrude, from their respective inner surface, less than or equal to half the distance that the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element. Said secondary protrusions may have a tapered form. That is, a secondary protrusion may taper (e.g. progressively reduce in cross-sectional area) from a base to a tip. A secondary protrusion may be a cone, a pyramid (e.g. having a polygonal base), or any other suitable three-dimensional shape. Said secondary protrusions may be arranged in any suitable manner (e.g. in any suitable regular pattern or irregular arrangement).

Optionally, in the first region 401, an outer surface of the first end effector element 404-1 and/or the second end effector element 404-2 may comprise a textured area 412 for gripping tissue. Textured area 412 may be configured to aid the primary protrusions in gripping tissue (e.g. in particular when the end effector is being gradually opened so as to stretch two portions of tissue apart). Textured area 412 may comprise tertiary protrusions. The tertiary protrusions may protrude, from their respective outer surface, a lesser distance than the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element. In an example, the tertiary protrusions may protrude, from their respective outer surface, less than or equal to half, or preferably less than or equal to a third, of the distance that the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element. The tertiary protrusions may also be "less aggressive" than the one or more primary protrusions and/or the secondary protrusions that can optionally be provided on the inner surface of an end effector element. For example, said tertiary protrusions may have a tapered form. That is, a tertiary protrusion may taper (e.g. progressively reduce in cross-sectional area) from a base to a tip. That said, the tertiary protrusions may be less "sharp" than the one or more primary protrusions and/or the secondary protrusions that can optionally be provided on the inner surface. For example, the tertiary protrusions may be flat-top (e.g. truncated) cones or pyramids. Additionally, or alternatively, the tertiary protrusions may be smaller than (e.g. protrude a lesser distance from their respective surfaces than) the secondary protrusions described herein -although this need not be the case. In an example, the tertiary protrusions may protrude less than 0.5mm, or preferably less than or equal to 0.25mm, from their respective outer surface -as illustrated by dimension "z" in Figure 4B. Other suitable tertiary protrusion distances could be used. This is advantageous because the tertiary protrusions, positioned on the outer surface of the end effector, can be exposed when the instrument is inserted into, and subsequently removed from, a patient -and so "less aggressive" (e.g. less sharp and/or smaller) tertiary protrusions can minimise any unintentional damage to the patient's tissues during this time. The tertiary protrusions may be arranged in any suitable manner (e.g. in any suitable regular pattern or irregular arrangement). It can be advantageous to arrange the tertiary protrusions in one or more rows that are substantially parallel with the longitudinal axis of the instrument shaft when the instrument 400 is in a straight configuration. Each row may comprise a plurality of tertiary protrusions. This arrangement can minimise the resistance provided by the tertiary protrusions were they to contact patient's tissues as the instrument is inserted into or removed from the patient (e.g. often in a direction substantially co-incident with the longitudinal axis of the instrument shaft).

As a result of one or more of the features described herein, the first region 401 may not be configured for gripping a needle and the first region 401 may not be configured for cutting (e.g. cutting a suture). For example, the primary protrusions of the first region may be too large to safely and reliably grip a needle and not sufficiently sharp to reliably cut (e.g. cut a suture).

The structure of the second region 402 is different to the structure of the first region 401. As shown in Figures 4A and 4B, in the second region 402, the inner surface 420 of each of the first end effector element 404-1 and the second end effector element 404-2 comprises a textured area 408 configured for gripping a needle. More generally, in the second region, the inner surface of the first end effector element and/or the second end effector element comprises a textured area configured for gripping a needle. That is, in other examples not shown in the Figures: one of the end effector elements may comprise a textured area 408 configured for gripping a needle whilst the other end effector element does not comprise a textured area 408 configured for gripping a needle.

Textured area 408 may comprise protrusions. The protrusions of textured area 408 may protrude, from their respective inner surface, a lesser distance than the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element. In an example, the protrusions of textured area 408 may protrude, from their respective inner surface, less than or equal to half, or preferably less than or equal to a third, of the distance that the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element. In an example, the protrusions of textured area 408 may protrude less than or equal to 0.5mm, or preferably less than or equal to 0.25mm, from their respective inner surface -e.g. illustrated as dimension "it in Figure 4B. Other suitable protrusion distances could be used. Said protrusions may have a tapered form. That is, each protrusion in textured area 408 may taper (e.g. progressively reduce in cross-sectional area) from a base to a tip. Each protrusion may be a cone (e.g. pointed or truncated), a pyramid (e.g. pointed or truncated), or any other suitable three-dimensional shape. The protrusions may be arranged in any suitable manner (e.g. in any suitable regular pattern or irregular arrangement). For example, the protrusions may be arranged in rows and/or columns. Each row and/or column may comprise a plurality of protrusions, or a single elongate protrusion that spans the second region 402. Said protrusions may be particularly suitable for gripping a needle, because they reduce the contact area between their respective end effector element and the needle, such that the pressure exerted over that contact area is increased. The density (e.g. number of protrusions per unit area) of protrusions in textured area 408 may be greater than the density of primary protrusions in the first region. In an example, the density of protrusions in textured area 408 may be at least double the density of primary protrusions in the first region.

In another example, the textured area 408 may alternatively, or additionally, comprise particles (e.g. irregularly shaped particles) adhered to the inner surface 420 (and/or the protrusions, in examples where the textured area 408 comprises protrusions). For example, particles may be adhered to the inner surface 420 and/or the protrusions in the textured area 408 by a diamond dust coating process. The average diameter of the adhered particles may be less than 0.15mm. Put another way, the diameter of the adhered particles may be in the range 0.0025mm to 0.1016mm.

Second region 402 may not be configured for grasping tissue and second region 402 may not be configured for cutting (e.g. cutting a suture). For example, the protrusions and/or particles of textured area 408 may be too small to reliably grasp tissue and not sufficiently sharp to reliably cut (e.g. cut a suture).

The structure of the third region 403 is different to the structures of both the first region 401 and the second region 402. As shown in Figures 4A and 4B, in the third region 403, the second end effector element 404-2 comprises a blade 410 configured for to cutting. The blade 410 may be configured for cutting a suture. That said, it is to be understood that it may also be possible to cut tissue (e.g. human or anatomical tissue) using a blade configured in this way. It may be desirable during the minimally invasive suturing procedure to trim (e.g. "tidy" up) an area of tissue before inserting a stitch. Hence, it can be desirable for the blade 410 to be configured for cutting a suture and/or tissue (e.g. human or anatomical tissue). More generally, in the third region, the first end effector element and/or the second end effector element may comprise a blade configured for cutting (e.g. cutting a suture and/or tissue). That is, the first end effector element 404-1 or the second end effector element 404-2 may comprise a blade 410 configured for cutting (e.g. cutting a suture and/or tissue) against the inner surface 420 of the other end effector element. Alternatively, both the first end effector element 404- 1 and the second end effector element 404-2 may comprise a respective blade configured for cutting (e.g. cutting a suture and/or tissue) against the blade of the other end effector element.

The blade may be manufactured separately and subsequently attached to the inner surface of its end effector element. Alternatively, a portion of the inner surface of an end effector element may be tapered towards the other end effector element, and optionally sharpened, so as to form a blade configured for cutting (e.g. cutting a suture and/or tissue).

Optionally, the blade(s) can be energisable by an electrosurgical generator. In this way, the blade 410 of the multi-functional instrument 400 could also be used for cauterising tissue (e.g. when cutting tissue, as described herein).

The skilled person would not typically design an end effector comprising both a tissue grasping portion and a blade. This is because the skilled person would likely be concerned of the risks associate with including a blade on the same instrument as is going to be used to grasp tissue -in particular, the risk of the blade unintentionally damaging (e.g. cutting) tissue as it is being grasped. In order to mitigate these risks, as shown in Figure 4B, the third region 403 comprising the blade may be a proximal region of the end effector, whilst the first region 401 configured for grasping tissue may be a distal region of the end effector. Those regions may be separated by the second region 402 configured for gripping a needle in an intermediate region of the end effector.

Additionally, or alternatively, the end effector may comprise a retractable blade guard (not shown in the Figures) and/or the blade itself may be retractable. The blade guard and/or blade may be retractable on demand (e.g. in response to a command from the remote surgeon console). In other examples, the retractable blade guard may be configured to shield the blade when the end effector is fully open. This can be useful if the surgeon prefers to fully open the jaws to grasp larger amounts of tissue. Alternatively, the retractable blade guard may be configured to expose the blade when the end effector is fully open. This can be useful if the surgeon prefers to fully open the jaws in order to expose the blade to cut a suture. In yet more examples, the blade may be retractable such that the blade retracts as the end effector opens (e.g. when the surgeon is intending to grasp tissue) and extends as the end effector closes beyond a certain threshold opening angle (e.g. when the surgeon is intending to cut a suture). Alternatively, the blade may be retractable such that the blade extends as the end effector opens beyond a certain threshold opening angle (e.g. if the surgeon prefers to cut a suture with the end effectors fully open) and retracts as the end effector closes (e.g. as the surgeon is in the process of grasping tissue). Various control modes of the surgical robot could be set to determine how and when the retractable blade guard and/or retractable blade are actuated. The surgeon may be able to select the appropriate control mode used based on their preferences.

By way of the three end effector regions described herein, instrument 400 is configured to perform each of the tasks identified herein that are involved in minimally invasive suturing. This is advantageous because a robotic surgical system comprising two robot arms for manipulating tissue, having an instrument 400 attached to each arm, could be used by a surgeon to insert a stitch into tissue without the need for any instrument changes. That is, the surgeon may use the first region 401 of the first instrument 400 controlled by one hand to tension the tissue to be sutured, and the second region 402 of the second instrument 400 controlled by their other hand to drive a suturing needle threaded with suture material through the tensioned tissue. The surgeon could then grip, using the second region 402 of the first instrument 400, the end of the needle that has passed through the tissue, and then release the other end of the needle from the second region 402 of the second instrument 400. The surgeon could then cut the stitch from the remainder of the suture material using the third region 403 of the second instrument 400. Were the surgeon to want to insert further stitches, the procedure could simply be repeated using the same two instruments 400. For completeness, it is to be understood that suturing could also be performed without need for instrument changes using one instrument 400 and a typical needle grasper.

Reducing the number of instrument changes that are performed during a suturing process reduces the duration of a suturing process. Furthermore, by using the instrument 400, which is configured to perform each of the tasks identified herein that are involved in minimally invasive suturing, the surgeon does not attempt to perform a task (e.g. grasping tissue) within the suturing process using an instrument (e.g. a needle holder) which is not configured for performing that task.

Given that a smaller area of each end effector element of the instrument 400 is dedicated to performing each task than in a typical instrument optimised for those specific individual tasks, the surgeon may find it relatively more difficult to perform each of those specific individual tasks. However, this can be outweighed by the benefits of: (i) reducing the duration of the suturing process (by reducing the number of instrument changes), and (ii) avoiding situations in which the surgeon may attempt to perform a task using an instrument that is not configured to perform that task. Both of these benefits can lead to safety improvements when performing a minimally invasive surgical procedure (e.g. less time under anaesthesia for the patient, and fewer instances of a surgeon using instruments to perform tasks for which they are not intended).

As such, it can be said that the instrument 400 has been optimised for performing the minimally invasive suturing process as a whole, rather than having been optimised for performing any one specific task.

Figures 5A and 5B schematically illustrate a second example robotic surgical instrument 500 according to the principles described herein. The instrument 500 comprises an end effector 504. In Figures 5A and 5B, for simplicity and ease of illustration, only the end effector 504 of said robotic surgical instrument 500 is shown. It is to be understood that the instrument may also comprise a shaft and an articulation connecting the shaft to the end effector. For example, the shaft and articulation may be of the type described with reference to Figures 2 and 3, or of any other suitable type.

As shown in Figures 5A and 5B, end effector 504 comprises a first end effector element 504-1 and a second end effector element 504-2. The first and second end effector elements 504-1, 504-2 are rotatably mounted with respect to one another -e.g. about joints 203-2, having the same properties as joints 203-2 described with reference to Figures 4A and 4B.

Each of the first and second end effector elements 504-1, 504-2 comprise an inner surface 520 that faces a respective inner surface 520 of the other end effector element when the end effector 504 is closed.

End effector 504 comprises a first region 501 configured for grasping tissue, a second region 502 configured for gripping a needle and a third region 503 configured for cutting (e.g. cutting a suture and/or tissue). The second region 502 and the third region 503 of end effector element 504 may have the same properties as the second region 402 and the third region 403 of end effector element 404 described with reference to Figures 4A and 4B. For example, in the second region 502, the first end effector element 504-1 and/or the second end effector element 504-2 may comprise a textured area 408 that comprises protrusions that protrude, from their respective inner surface, a lesser distance than the one or more primary protrusions 506 protrude from the plane 522 that is substantially defined by the inner surface, in the second region, of their respective end effector element In Figures 5A and 5B, in the first region 501, the first end effector element 504-1 and the second end effector element 504-2 each comprise a primary protrusion 506 configured for grasping tissue. More generally, in the first region, the first end effector element and/or the second end effector element may comprise one or more primary protrusions configured for grasping tissue. That is, in other examples not shown in the Figures: one of the end effector elements may comprise one or more primary protrusions whilst the other end effector element does not comprise any primary protrusions; one of the end effector elements may comprise one primary protrusion whilst the other end effector element comprises a plurality of primary protrusions; or both of the end effector elements may comprises a plurality of primary protrusions.

Each primary protrusion 506 may have a tapered form. That is, a primary protrusion may taper (e.g. progressively reduce in cross-sectional area) towards a tip. The primary protrusions shown in Figure 5A have a similar form to those of a "tenaculum" tissue grasper.

As shown in Figure 5A, the primary protrusions 506 define a portion of the outer profile of the end effector 504 when the end effector is closed. That portion of the outer profile may be blunt (e.g. gradually curved). This is advantageous as it facilitates the insertion of the instrument 500 into, and the subsequent removal of the instrument 500 from, a patient without causing unintentional damage to the patient's tissues.

Figure 5B shows the end effector 504 in a partially open configuration. In Figure 5B, features of the second region 502 and third region 503 have been omitted for ease of illustration and understanding. In Figure 5B, for example, each of the primary protrusions 506 protrudes by between 0.3mm and 4mm from a plane 522 that is substantially defined by the inner surface 520, in the second region, of its respective end effector element -e.g. illustrated as dimension "x" in Figure 5B. It is to be understood that the primary protrusion distance of between 0.3mm and 4mm provided herein is by way of example only. Other suitable primary protrusion distances could be used. A suitable primary protrusion distance can be selected in dependence on the size of the end effector elements (e.g. generally speaking, larger end effector elements may comprise larger primary protrusions).

Optionally, in the first region 501, the first end effector element 504-1 and/or the second end effector element 504-2 may comprise textured areas for gripping tissue having the same properties as the textured areas for gripping tissue described with reference to Figure 4A and 4B.

Multi-functional instrument 500 may be used in an equivalent manner to multifunctional instrument 400, as described herein.

It is to be understood that the multi-functional instruments described herein may also be used during procedures other than minimally invasive suturing. For example, any procedure in which any two or more of tissue grasping, needle holding and cutting are performed, and in which instrument changes are typically performed throughout that procedure, could benefit from use of the multi-functional instruments described herein.

One example of such a procedure that does not necessarily involve minimally invasive suturing is minimally invasive hernia repair. In minimally invasive hernia repair a mesh is placed to reinforce an area of anatomical tissue. During this procedure, tissue incisions are made (e.g. using the cutting functionality of the multifunctional instrument described herein) and tension is applied to the tissue to which the mesh will be attached (e.g. using the tissue grasping functionality of the multifunctional instrument described herein). Optionally, the mesh can be attached and/or the surgical site can be closed by minimally invasive suturing (e.g. using the multifunctional instrument described herein), or alternatively by surgical stapling or use of surgical glue. It is also to be understood that the multi-functional instruments described herein need not be used in robotic surgical systems comprising two robot arms for manipulating tissue.

Also disclosed herein is a robotic surgical instrument configured for grasping tissue in which the first end effector element and/or the second end effector element comprises one or more primary protrusions configured for grasping tissue and each of the primary protrusions can be received in a respective recess provided in the other end effector element when the end effector is closed, as described with reference to Figure 4A and 4B. Said robotic surgical instrument configured for grasping tissue may comprise any one or more of the other features of the first region 401 described herein with reference to Figure 4A and 4B. Said robotic surgical instrument configured for grasping tissue need not comprise any of the features of the second region 402 or the third region 403 described herein with reference to Figure 4A and 4B.

The applicant hereby discloses in isolation each individual feature described herein and any combination of two or more such features, to the extent that such features or combinations are capable of being carried out based on the present specification as a whole in the light of the common general knowledge of a person skilled in the art, irrespective of whether such features or combinations of features solve any problems disclosed herein, and without limitation to the scope of the claims. The applicant indicates that aspects of the present invention may consist of any such individual feature or combination of features. In view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention.

Claims

CLAIMS1. A robotic surgical instrument comprising an end effector, the end effector comprising: a first end effector element and a second end effector element, each of the first and second end effector elements comprising an inner surface that faces a respective inner surface of the other end effector element when the end effector is closed; a first region configured for grasping tissue, wherein, in the first region, the first end effector element and/or the second end effector element comprise one or more primary protrusions configured for grasping tissue; a second region configured for gripping a needle, wherein, in the second region, the inner surface of the first end effector element and/or the second end effector element comprises a first textured area configured for gripping a needle; and a third region configured for cutting, wherein, in the third region, the first end 15 effector element and/or the second end effector element comprises a blade configured for cutting.
2. A robotic surgical instrument as claimed in claim 1, wherein the first region is a distal region of the end effector, the second region is an intermediate region of the end effector, and the third region is a proximal region of the end effector.
3. A robotic surgical instrument as claimed in claim 2, wherein the robotic surgical instrument comprises a shaft and an articulation connecting the shaft to the end effector, the shaft being proximal to the end effector.
4. A robotic surgical instrument as claimed in any of claims 1 to 3, wherein the structure of the first region is different to the structure of the second region.
5. A robotic surgical instrument as claimed in any preceding claim, wherein the first region is not configured for gripping a needle and the first region is not configured for cutting.
6. A robotic surgical instrument as claimed in any preceding claim, wherein the second region is not configured for grasping tissue and second region is not configured for cutting.
7. A robotic surgical instrument as claimed in any preceding claim, wherein the third region is not configured for grasping tissue and third region is not configured for gripping a needle.
8. A robotic surgical instrument as claimed in any preceding claim, wherein, in the first region, in at least one configuration of the end effector, each of the one or more primary protrusions comprised by the first end effector element or the second end effector element protrudes towards the inner surface of the other end effector element.
9. A robotic surgical instrument as claimed in any preceding claim, wherein, in the first region, the one or more primary protrusions do not protrude beyond the outer profile of the end effector when the end effector is closed.
10. A robotic surgical instrument as claimed in claim 9, wherein, when the end effector is closed, each of the one or more primary protrusions are received in respective recesses provided in the other end effector element.
11. A robotic surgical instrument as claimed in claim 9 or 10, wherein the first end effector element comprises a first primary protrusion and the second end effector element comprises a first recess for receiving the first primary protrusion when the end effector is closed, and the second end effector element comprises a second primary protrusion and the first end effector element comprises a second recess for receiving the second primary protrusion when the end effector is closed.
12. A robotic surgical instrument as claimed in any of claims 9 to 11, wherein each of the one or more primary protrusions are retractable into the inner surface of their respective end effector element.
13. A robotic surgical instrument as claimed in any of claims 1 to 8, wherein, in the first region, the one or more primary protrusions define a blunt portion of the outer profile of the end effector when the end effector is closed.
14. A robotic surgical instrument as claimed in any preceding claim, wherein, in the first region, the one or more primary protrusions are angled towards the proximal end of the end effector.
15. A robotic surgical instrument as claimed in any preceding claim, wherein, in the first region, the one or more primary protrusions have a tapered form.
16. A robotic surgical instrument as claimed in any preceding claim, wherein, in the second region, the first textured area comprises protrusions that protrude, from their respective inner surface, a lesser distance than the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element.
17. A robotic surgical instrument as claimed in any preceding claim, wherein, in the first region, the inner surface of the first end effector element and/or the second end effector element comprises a second textured area for gripping tissue.
18. A robotic surgical instrument as claimed in claim 17, wherein the second textured area comprises secondary protrusions that protrude, from their respective inner surface, a lesser distance than the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element.
19. A robotic surgical instrument as claimed in any preceding claim, wherein, in the first region, an outer surface of the first end effector element and/or the second end effector element comprises a third textured area for gripping tissue.
20. A robotic surgical instrument as claimed in claim 19, wherein the third textured area comprises tertiary protrusions that protrude, from their respective outer surface, a lesser distance than the one or more primary protrusions protrude from a plane that is substantially defined by the inner surface, in the second region, of their respective end effector element.
21. A robotic surgical instrument as claimed in any preceding claim, wherein the S blade is retractable.
22. A robotic surgical instrument as claimed in any preceding claim, wherein the end effector comprises a retractable blade guard.
23. A robotic surgical instrument as claimed in any preceding claim, wherein, in use, the blade is energisable by an electrosurgical generator.
24. A robotic surgical instrument as claimed in any preceding claim, wherein the first end effector element or the second end effector element comprises a blade configured for cutting against the inner surface of the other end effector element.
25. A robotic surgical instrument as claimed in any of claims 1 to 23, wherein both the first end effector element and the second end effector element comprise a respective blade configured for cutting against the blade of the other end effector 20 element.