Actuated wrist mechanism

Abstract

An actuated wrist mechanism configured to move and / or operate a surgical tool is disclosed. The articulated wrist mechanism comprises an abutment portion having a first abutment surface configured to abut, in use, against an abutment surface of a surgical tool, and one or more tendons configured to interconnect, in use, a portion of the surgical tool and an actuator. In use, actuation of the actuator causes force to be transmitted to the surgical tool via the one or more tendons, thereby causing the surgical tool to move and / or operate.

Description

[0001] ACTUATED WRIST MECHANISM

[0002] FIELD OF THE PRESENT INVENTION

[0003] The present invention relates to an actuated wrist mechanism, a surgical instrument, a method, a method of surgery, a method of performing arthroscopic surgery, apparatus, a robot or robotic system, and a surgical robot or surgical robotic system.

[0004] BACKGROUND

[0005] Arthroscopy is a minimally invasive surgical procedure that allows surgeons to diagnose and treat joint issues. During this procedure surgeons use specialised instruments to navigate within the joint through small incisions or portals. The procedure typically involves the use of a camera (arthroscope) and various instruments such as shavers, punches and suture passers.

[0006] Surgeons must be able to manoeuvre these instruments in tight spaces, often contending with the curvature of the joint and limited access points. Accordingly, arthroscopic surgical instruments tend to be long and thin in order to reach the area of surgical interest. Due to the small size, there is a trade-off between size, mechanical strength and (where applicable) the size of a suction channel to clear debris from the surgical site.

[0007] Current arthroscopic surgical instruments are typically up to 220 mm long and comprise a straight stiff shaft, an instrument-specific tip and a handle. Known arthroscopic surgical instruments provide limited manoeuvrability due to the portal locations and the complex curvature of joints. As will be understood by those skilled in the art, conventional arthroscopic surgical instruments are positioned by leveraging the instrument shaft against the skin side of the portal to position the tip into the area of surgical interest with visual aid of the arthroscope. Conventional arthroscopic surgical instruments suffer from problems due to limited access and manoeuvrability, delays (e.g. due to portal changes or positioning difficulties), unintended tissue damage as well as compromise in terms of task quality.

[0008] Furthermore, current instruments only provide limited qualitative force feedback. For example, guide rod and trochar mechanisms of current instruments such as graspers and punches possess a high friction profile which significantly reduces the signal-to- noise ratio of the haptic feedback of the handle. Additional tensile feedback is also lost due to the friction between the instrument shaft and the portal. Consequently, surgeons mostly rely on visual feedback (e.g. the ability to pull the tissue when the instrument jaws are closed) to gauge if sufficient force is being applied to the tissue by the jaws of the instrument. Since the forces applied to the tissue during the surgery are not captured, surgical outcomes can only be assessed by the tissue condition at follow-up and those outcomes cannot be quantitatively related back to forces applied during surgery.

[0009] Current instruments rely solely on the surgeon to capture tissues and suture within the joint. Aiding technology such as suction to help position tissues and suture within the instrument are mostly lacking and only select instrument groups such as shavers and arthroscopes possess any irrigation / suction functionality.

[0010] Actuated wrist instruments are known which aim to enhance the manoeuvrability and precision of surgical tools. These instruments typically feature an articulating wrist mechanism that allows for greater flexibility and control within the joint. Most solutions can be classified as either: (i) pin wrist joints providing a sharp angulation at the proximal end of the instrument tip; or (ii) as curved wrist joints which form a longer arched “neck” at the proximal end of the instrument tip. For example, a known curved wrist joint uses a series of interconnected segments that can be manipulated to bend the instrument’s tip in various directions approximating an arc. A known pin wrist joint consists of a central pin that allows the instrument’s tip to pivot or rotate around it, offering a sharp bend.

[0011] One major drawback, however, of current actuated wrist instruments is their inability to transmit and withstand the mechanical forces encountered during arthroscopy while constraining the instrument tip position. This limitation can result in unintended instrument tip movements and insufficient force applied to the tissue during surgical tasks (e.g. suture passing). This limitation is especially pronounced in curved wrist joints which is why they are mostly utilised for non-loadbearing instruments such as an arthroscope. The lack of ridged constraints prevents this type of instrument from being suitable for use in high load-bearing surgical tasks such as probing, picking bone or scar tissue, debridement, removal of rigid bodies, reduction of tissue and cutting or punching of stiff structures such as calcified tendon or meniscus. In such applications, the weak mechanical backbone of curved wrist joints frequently fails. As a result, conventional instruments are often unable to perform the task and in some situations may result in mechanical failure of the instrument and possible injury to the patient.

[0012] Furthermore, existing instruments typically do not include integrated channels for suction and irrigation. The absence of such features necessitates the use of additional instruments such as the arthroscope or shaver to provide suction, limiting the surgeon’s control over the fluid management of the joint and not providing further aiding functions e.g. to capture tissue or suture. This limitation is especially pronounced in pint joint wrists since the classic pin design does not facilitate a fluid channel near the distal tip of the instrument.

[0013] Additionally, current instruments do not provide real-time force measurement, which is desirable for ensuring precise force application and preventing tissue damage. Without accurate force feedback, surgeons may inadvertently apply excessive or insufficient force, leading to unintended tissue damage or incomplete constraint of tissues.

[0014] US-8142421 discloses a positively positionable multi-disk wrist mechanism which includes a plurality of disks or vertebrae stacked in series. Each vertebra is configured to rotate in pitch or in yaw with respect to each neighbouring vertebra. Actuation cables are used to manipulate and control movement of the vertebrae. The cables are actuated by a pivoted plate cable actuator mechanism. A central non-enclosed channel is disclosed.

[0015] US 2019 / 0290309 discloses an articulating mechanism capable of transmitting torque for remote manipulation of a surgical or diagnostic tool and comprises at least two adjacent links. A first adjacent link of the adjacent links has a ball and a second adjacent link of the adjacent links has a socket for receiving the ball to form a ball and socket joint. The ball and socket joint includes at least one engaging pin and a reciprocal slot that provides for torque transmission between the adjacent links while also allowing for pivoting movement of the first adjacent link relative to the second adjacent link. The articulating mechanism also comprises at least one set of cables connecting the first adjacent link and the second adjacent link to one another such that movement of the first adjacent link causes corresponding relative movement of the second adjacent link. A central semi-enclosed channel is also disclosed.

[0016] US 11 / 666,374 discloses a medical instrument with a jaw and a friction-coupled drive cable. Drive cables are used to both actuate mechanical components of a wrist mechanism or an effector and to electrically energise the effector. Each blade has a cap that locks into the blades. Caps slip onto pins and have a notch that traps a crimp. Alternatively, each cap can be permanently attached to the corresponding blade e.g. by swaging. Crimp is attached to a cable loop having ends that extend back as cables. When assembled into distal clevis, caps hold crimps in respective notches so that cables are attached to blades. Cables and blades are made of a conductive material and a medical instrument can be electrically energised. Portions of cables in the wrist mechanism may be made of stranded metal cable for flexibility and may be swaged to provide smoother cable surfaces and also so as to reduce friction. An electrically insulating coating is not required on any of the cables. Electrical isolation is achieved by using an insulating main tube through which drive cables extend from a backend mechanism to the wrist mechanism. Seals may be employed at the end of the main tube to isolate electrically energised cables from conductive fluids that may be in contact with the instrument during a medical procedure. Limiting contact to conductive fluids is desired because liquid in contact with energised cables can directly conduct the full working voltage from the cables to the patient and cause alternate site burns. The seals create a barrier to break that of the direct conductive path. US-9173643 discloses a pitch-roll-yaw surgical tool. A robotic surgical tool is disclosed that includes an elongate shaft having a working end and a shaft axis.

[0017] US- 10772690 discloses a passive preload and capstan drive for surgical instruments. The system comprises a medical instrument including a rotatable capstan. The rotatable capstan includes a capstan coupling member that can engage with a drive shaft coupling member such that rotation of the drive shaft causes rotation of the capstan about a drive axis concentric with the drive shaft and can disengage from the drive shaft coupling member such that rotation of the drive shaft does not cause rotation of the capstan. The control of the jaws and any joint in end effector or shaft can be effected in a closed loop by basing the motor control torques for that joint on measurement of the current position of the joint. Such measurements can, for example, be done by using a sensing technology such as position sensors using fibre Bragg gratings and fibre optic shape sensors. For the control loop, a control system compares a desired joint position with a measured joint position to compute a joint position error. A control or correction torque is then computed based on the current value of the joint position error, for instance using a Proportional Derivative Integral control law. Depending on the control torque sign indicating a clockwise or counterclockwise correction, one of the motors associated with the joint is commanded to apply a torque to its associated capstan while the other motor associated with the joint is commanded to zero its motor torque, thereby letting go of its associated capstan. In this way, the joint is placed in the desired position.

[0018] US-7121781 relates to surgical instrument with a universal wrist and discloses a robotically controlled endoscopic medical instrument that includes an end effector coupled to a wrist. The wrist provides two separate degrees of freedom about the same pivot point. The end effector can be moved and actuated by pins. The pins allow for a compact minimally invasive medical instrument that has a wrist with two degrees of freedom. The pins may be coupled to a tool driver. The tool driver may be a device that pushes and pulls the pins. The tool driver may include three driver motors. The wrist may include a ball joint that is attached to a stationary pin and seated within a base of the end effector. The instrument may be constructed so that the pivot point is located at the centre of the ball joint. Alternatively, the wrist may include a universal joint that allows movement of the end effector about the pivot point. The linkages may also be coupled to the end effector by ball joints. The wrist may further heave a bellows to cover the linkages and transmit torque from the end effector to the shaft of the instrument.

[0019] As will be explained in more detail below, the known arrangements such from various problems. In particular, the known arrangements are relatively complex, cumbersome and do not afford themselves to miniaturisation. Furthermore, the known arrangements are not suited for performing arthroscopic surgery and transmitting force to a surgical tool which may be operating on a joint. The known arrangements suffer from a number of problems which limit their effectiveness and clinical utility, particularly in the context of minimally invasive procedures such as arthroscopy. One major drawback of conventional arrangements is that they tend to be relatively complex, often comprising multiple interconnected components, intricate linkages and elaborate actuation systems. This complexity not only increases the cost and difficulty of manufacturing and assembly, but also raises the risk of mechanical failure or malfunction during use. The presence of numerous moving parts can also make cleaning, sterilisation and maintenance more challenging, which is a critical consideration in surgical environments.

[0020] In addition, the known arrangements tend to be cumbersome, with bulky or awkward geometries that are not easily accommodated within the restricted anatomical spaces encountered during arthroscopic procedures. Their size and shape can impede the surgeon’s ability to manoeuvre the instrument freely within the joint, particularly when working through small portals or in areas with limited access. This lack of ergonomic refinement can lead to surgeon fatigue, reduced precision and increased risk of inadvertent tissue damage.

[0021] A further disadvantage is that conventional arrangements do not lend themselves to miniaturisation. The need to incorporate multiple mechanical elements, such as gears, pulleys, or rigid linkages, often results in a device that is too large or unwieldy for true minimally invasive surgery. As a result, it is difficult to scale down these designs to the small diameters required for arthroscopic instruments, which must be both slender and robust to navigate the joint space effectively.

[0022] Moreover, the known arrangements are not well suited for performing arthroscopic surgery, particularly when it comes to the reliable transmission of force to a surgical tool operating on a joint. Many conventional devices lack the mechanical efficiency or structural integrity needed to deliver sufficient force to the distal end of the instrument without significant losses due to friction, backlash, or deformation of the mechanism. This can result in poor responsiveness, reduced tactile feedback, and an inability to perform demanding surgical tasks such as cutting, grasping, or manipulating dense or resistant tissues. In some cases, the inability to transmit adequate force may even lead to incomplete procedures or the need to convert to open surgery, thereby negating the benefits of minimally invasive techniques.

[0023] It is therefore desired to provide an improved actuated wrist mechanism. SUMMARY

[0024] According to an aspect there is provided an actuated wrist mechanism configured to move and / or operate a surgical tool, wherein the articulated wrist mechanism comprises: an abutment portion having a first abutment surface which is configured to abut, in use, against an abutment surface of a surgical tool; and one or more tendons configured to interconnect, in use, a portion of the surgical tool and an actuator; wherein, in use, actuation of the actuator causes force to be transmitted to the surgical tool via the one or more tendons thereby causing the surgical tool to move and / or operate.

[0025] An advantage of this arrangement is that the use of one or more tendons in combination with an abutment portion enables precise and controlled transmission of force from the actuator to the surgical tool, allowing for accurate movement and operation of the tool. This configuration provides improved dexterity and responsiveness compared to conventional mechanisms, enhances the ability to perform complex surgical tasks in confined spaces, and facilitates miniaturisation and robust force transmission suitable for

[0026] According to various embodiments in terms of shear forces the first abutment surface may be arranged to operate in all or multiple directions e.g. both pitch and yaw.

[0027] The first abutment surface may be arranged to permit movement in one or more degrees or directions of freedom which can be in-line with the surface axis of the buttress.

[0028] An advantage of this arrangement is that by configuring the first abutment surface to operate in all or multiple directions (such as both pitch and yaw) the mechanism enables the surgical tool to be manipulated with a high degree of dexterity and flexibility. This multi-directional capability allows the instrument tip to be precisely positioned and oriented within the joint, facilitating access to anatomically challenging or confined areas that would otherwise be difficult to reach with conventional instruments.

[0029] Furthermore, by permitting movement in one or more degrees or directions of freedom, particularly in-line with the surface axis of the buttress, the mechanism provides smooth and controlled articulation of the surgical tool. This enhances the surgeon’s ability to perform complex manoeuvres, reduces the need for repositioning or changing portals and minimises the risk of unintended tissue damage. The result is improved surgical precision, efficiency, and overall clinical outcomes, especially in minimally invasive procedures where access and manoeuvrability are critical. The actuated wrist mechanism according to various embodiments is advantageous compared with known arrangements in that the use of tendons and abutment surfaces between the actuated wrist mechanism and the surgical tool enables the surgical tool to be manipulated so as to might tight controlled movements.

[0030] The disclosed arrangement is also less complex than conventional arrangements and can be miniaturised in a way which is not possible with conventional arrangements.

[0031] Furthermore, the tendons which are utilised according to various embodiments are particularly effective in the transmission of force to the surgical tool and hence the overall apparatus is more robust than conventional arrangements.

[0032] The actuated wrist mechanism according to various embodiments offers several advantages over known arrangements. The use of tendons and abutment surfaces between the actuated wrist mechanism and the surgical tool enables the surgical tool to be manipulated with tight, controlled movements thereby providing enhanced precision and dexterity during surgical procedures.

[0033] The apparatus according to various embodiments is also less complex than conventional mechanisms, reducing the number of components and potential points of failure. This simplification not only improves reliability and ease of maintenance but also allows the mechanism to be miniaturised to a degree that is not achievable with traditional designs. As a result, the device is particularly well suited for minimally invasive procedures where space is limited and instrument size is critical.

[0034] According to various embodiments the tendons are particular effective in transmitting force directly to the surgical tool. This efficient force transmission results in a more robust and responsive apparatus, allowing the surgeon to perform demanding tasks with greater confidence and control. The combination of precise actuation, reduced complexity, and improved robustness represents a significant improvement over conventional arrangements.

[0035] According to various embodiments the tendons may be manufactured from a variety of materials selected to provide the necessary strength, flexibility, and biocompatibility required for surgical applications. Suitable materials include metals such as stainless steel or other medical-grade alloys, which offer excellent tensile strength and durability. Alternatively, high-strength polymers such as polyethylene, polyether ether ketone (PEEK), or aramid fibres (for example, Kevlar) may be used to provide flexibility and resistance to fatigue. In some embodiments, the tendons may be formed from braided or stranded wire cables to enhance both flexibility and load-bearing capacity. Carbon fibre or composite materials may also be employed to achieve a balance of strength and lightweight properties. In certain cases, a combination of materials may be utilised, such as a metallic core surrounded by a polymeric or composite sheath, in order to optimise the mechanical and biocompatible characteristics of the tendon.

[0036] It will be appreciated, therefore, that the actuated wrist mechanism according to various embodiments represents a significant advance in the art.

[0037] The actuated wrist mechanism may further comprise one or more actuators for actuating the one or more tendons.

[0038] According to another aspect there is provided apparatus comprising: an actuated wrist mechanism as described above; and a surgical tool abutted against the actuated wrist mechanism.

[0039] The first abutment surface may comprise a concave (or other shaped) abutment surface and the abutment surface of the surgical tool may comprise a convex (or other shaped) abutment surface.

[0040] Alternatively, the first abutment surface may comprise a convex (or other shaped) abutment surface and the abutment surface of the surgical tool may comprise a concave (or other shaped) abutment surface.

[0041] The surgical tool and the actuated wrist mechanism may form or cooperate via a ball and socket arrangement or interface.

[0042] The surgical tool may be configured to: (i) pitch up and / or pitch down; and / or (ii) yaw left and / or yaw right; and / or (iii) roll or rotate in a first direction and / or roll or rotate in a second direction; and / or (iv) simultaneously pitch and yaw. The first and second directions may be opposed to each other. The first direction may be clockwise (anticlockwise) and the second direction may be anticlockwise (clockwise).

[0043] The various embodiments are particularly advantageous in that the provision of one or more actuators for actuating the tendons enables precise and responsive control of the surgical tool, allowing for fine adjustments and complex movements during surgical procedures. The use of complementary abutment surfaces, such as a concave surface on the wrist mechanism and a convex surface on the surgical tool, or vice versa facilitates a stable and robust interface, reducing play and ensuring reliable force transmission.

[0044] The ability to form a ball and socket arrangement or interface between the actuated wrist mechanism and the surgical tool provides multiple degrees of freedom, allowing the tool to pitch, yaw, and roll as required. This greatly enhances the dexterity and manoeuvrability of the instrument tip, enabling the surgeon to access and operate in anatomically challenging or confined spaces. The configuration also allows for simultaneous movements in more than one direction, supporting complex surgical tasks and improving overall surgical precision and efficiency. The versatility of movement encompassing pitch, yaw, roll, and combinations thereof represents a significant improvement over conventional instruments, which are typically limited in their range of motion and adaptability.

[0045] The surgical tool may be configured to be positively actuated by the one or more tendons.

[0046] The one or more tendons may be connected to one or more motors, wherein the one or more motors may be configured to transmit force to the surgical tool via the one or more tendons.

[0047] The apparatus may further comprise a force measuring device configured to measure the force transmitted to the surgical tool via the one or more tendons.

[0048] The force measuring device may be configured to measure a back electromotive force (“EMF”) experienced by the one or more motors, wherein the measured back electromotive force may correlate with the force(s) exerted by the surgical tool and / or experienced by the surgical tool.

[0049] According to various embodiments, configuring the surgical tool to be positively actuated by one or more tendons enables precise and reliable control over the movement and operation of the tool to be achieved, enabling the surgeon to perform delicate and complex tasks with greater accuracy. Connecting the tendons to one or more motors allows for efficient and responsive force transmission, further enhancing the dexterity and performance of the instrument. The inclusion of a force measuring device, particularly one capable of measuring back electromotive force (EMF) from the motors, offers real-time quantitative feedback on the forces being applied to or experienced by the surgical tool. This enables the surgeon to monitor and adjust the applied force during a procedure, reducing the risk of tissue damage and improving surgical outcomes. The ability to correlate back EMF with actual forces exerted provides a valuable tool for both intraoperative control and post-operative assessment, supporting safer and more effective minimally invasive surgery.

[0050] The actuated wrist mechanism and / or the surgical tool may further comprise a cannula or one or more fluid flow channels.

[0051] The cannula (or fluid flow channel(s)) may be configured to provide one or more suction channels. The cannula (or fluid flow channel(s)) may be configured to provide one or more irrigation channels.

[0052] The apparatus may further comprise one or more integrated suction and irrigation channels.

[0053] The one or more integrated suction and irrigation channels may be configured to enable fluid management at an instrument tip of the surgical tool.

[0054] The one or more integrated suction and irrigation channels may be configured to capture tissue and / or provide a suture port and / or provide a clear surgical field.

[0055] The inclusion of a cannula or one or more fluid flow channels within the actuated wrist mechanism and / or the surgical tool provides several important advantages. By configuring these channels to serve as suction and / or irrigation channels, the apparatus enables effective fluid management directly at the instrument tip. This allows for the removal of debris, blood or other fluids from the surgical site thereby maintaining a clear field of view for the surgeon and reducing the need for additional instruments.

[0056] Integrated suction and irrigation channels can also facilitate the capture and removal of tissue fragments, assist in the precise placement of sutures and help to control bleeding during procedures. The ability to manage fluids at the distal end of the instrument enhances procedural efficiency, minimises interruptions, and supports safer, more effective minimally invasive surgery. Furthermore, the integration of these channels within the instrument reduces the overall number of devices required in the surgical field, improving ergonomics and workflow for the surgical team.

[0057] According to another aspect there is provided an arthroscopic surgical instrument comprising apparatus as described above.

[0058] According to another aspect there is provided a method comprising: providing apparatus as described above; and actuating the actuated wrist mechanism in order to move and / or control the surgical tool.

[0059] According to another aspect there is provided a method of surgery comprising a method as described above.

[0060] According to another aspect there is provided a method of performing arthroscopic surgery comprising a method as described above. According to another aspect there is provided a surgical instrument comprising: an actuated wrist mechanism comprising a shaft having a first abutment surface, wherein the shaft comprises one or more grooves or channels; a surgical tool having a second abutment surface, wherein the first abutment surface is abutted against the second abutment surface and wherein the surgical tool further comprises one or more recesses or sockets; one or more tendons, each tendon having an end portion, wherein each end portion is located within one of the one or more recesses or sockets; and one or more motors for actuating the one or more tendons, wherein the one or more motors are configured to transmit force to the surgical tool via the one or more tendons in order to move and / control the operation of the surgical tool in use.

[0061] An advantage of this arrangement is that it enables precise and robust control of the surgical tool through the direct transmission of force from the motors to the tool via the tendons. The use of abutting surfaces and dedicated grooves or channels ensures stable alignment and reliable articulation between the actuated wrist mechanism and the surgical tool. By locating the tendon end portions within corresponding recesses or sockets, the system achieves secure engagement and efficient force transfer, allowing for highly controlled and dexterous movements. This configuration supports complex surgical tasks, enhances manoeuvrability within confined anatomical spaces, and facilitates miniaturisation of the instrument for minimally invasive procedures.

[0062] The surgical instrument may further comprise a force measuring device for measuring the back electromotive force (“EMF”) generated by the one or more motors, wherein the force measuring device generates an output or signal indicative of the force(s) exerted by the surgical tool and / or the force(s) experienced by the surgical tool.

[0063] It will be understood that whilst various embodiments relate to an actuated wrist mechanism for a surgical tool, that other embodiments are contemplated wherein more generally a mechanism for moving and / or operating an attachment is disclosed.

[0064] For example, according to another aspect there is provided apparatus comprising: a mechanism configured to control the movement and / or operation of an attachment, wherein the mechanism comprises a shaft portion comprising a collar, wherein the collar comprises a first abutment surface and wherein optionally the shaft portion further comprises one or more grooves; an attachment comprising a second abutment surface, wherein the second abutment surface abuts against the first abutment surface; one or more tendons, wherein optionally each tendon is arranged in one of the one or more grooves, and wherein optionally each tendon comprises an end portion; one or more motors for actuating the one or more tendons; and a control system configured to cause the one or more motors to actuate one or more of the tendons so as to move and / or operate the attachment.

[0065] According to various embodiments a robot comprising apparatus as described above may be provided.

[0066] In addition, according to another aspect there is provided a surgical robot comprising apparatus as described above. The surgical robot may comprise a surgical robot which is configured to perform arthroscopic surgery.

[0067] According to an aspect there is provided an actuated wrist mechanism configured to control the movement and / or operation of a surgical tool, wherein the actuated wrist mechanism comprises: a shaft portion comprising a collar, wherein the collar comprises a first abutment surface which is configured to abut, in use, against an abutment surface of a surgical tool; wherein the shaft portion further comprises one or more grooves; one or more tendons, wherein each tendon is arranged in one of the one or more grooves, and wherein each tendon comprises an end portion; wherein, in use, the one or more of the tendons are configured to control the movement and / or operation of a surgical tool.

[0068] A person skilled in the art will appreciate that an actuated wrist instrument according to various embodiments as disclosed herein is a specialised tool which is designed to enhance the precision and dexterity of surgeons during minimally invasive procedures, particularly arthroscopy. The surgical instrument is constructed with several key components that enable it to perform complex manoeuvres within the tight confines of a joint.

[0069] The surgical instrument may comprise a handle which a surgeon may grip and which enables the surgeon to control and manipulate the instrument’s movements. The instrument may comprise a shaft which is connected to the handle and which is designed for insertion through small incisions thereby minimising tissue damage and promoting quicker recovery of the patient. The actuated wrist instrument or mechanism allows the instrument’s tip to move in multiple directions in a flexible manner.

[0070] The tip of the instrument may be fitted with various tools such as scissors which may be tailored to the specific needs of a particular surgical procedure. A control mechanism, whether mechanical or robotic, may be provided which enables a surgeon to make fine adjustments to the tip’s position and orientation thereby ensuring precise manipulation of tissues within the joint. The actuated wrist instrument or mechanism according to various embodiments may allow a surgeon to diagnose and treat joint problems with a high degree of accuracy. For instance, during a knee arthroscopy, the instrument may be used to visualise the interior of the joint, grasp and remove damaged tissue or precisely suture torn ligaments. The enhanced manoeuvrability provided by the actuated wrist mechanism according to various embodiments results in such tasks being able to be performed with minimal invasiveness thereby reducing patient trauma and accelerating recovery times.

[0071] The actuated wrist instrument or mechanism according to various embodiments represents a significant advance in the art and empowers surgeons to perform intricate procedures with greater ease and improved patient outcomes.

[0072] It will be understood that with conventional instruments a source of surgical error (e.g. unintended tissue damage) may relate to the lack of mechanical feedback and surgeon control. The forces applied during surgical tasks such as suturing have been shown to significantly affect patient outcomes but are unknown during the procedure when using a conventional instrument. It will be understood that it is not currently possible for a surgeon (or other user) to quantitively gauge these values during surgery.

[0073] Accordingly, it will be recognised that the actuated wrist instrument or mechanism according to various embodiments provides a high degree of mechanical feedback and in particular the force applied by the instrument whilst performing a surgical task can be recorded. As such, the actuated wrist mechanism according to various embodiments is particularly beneficial and solves various deficiencies associated with conventional arrangements.

[0074] It will also be understood that the quality of the tissue cut which may be achieved via a cutting instrument such as a punch or shaver affects the prognosis of the surgical outcome but is limited by access issues. A stiff straight shaft cannot sufficiently provide access to all locations of the joint due to the complex curvature of the local anatomy, which requires high angulation over small radii compared to the total length of the instrument. Again, a surgical instrument according to various embodiments which is connected to an actuated wrist mechanism according to various embodiments is particularly beneficial in terms of having significantly improved manoeuvrability compared to conventional arrangements and is also able to transmit higher force to a surgical tool than conventional arrangements.

[0075] Current instruments lack either dexterity-promoting features or strength features. By way of contrast, an actuated wrist instrument or mechanism according to various embodiments possesses both distal tip mechanisms which allows the surgeon to reposition the instrument tip during use whilst at the same time providing a sufficiently high load-bearing capacity as needed for surgery. In short, the apparatus according to various embodiments solves the problem (which is not solved by conventional arrangements) of providing a tool which can be used for high precision arthroscopic surgery which is both dexterous and strong (in the sense of allowing force to be transmitted to the surgical tool).

[0076] The instrument according to various embodiments seeks to address the limitations of current arthroscopic instruments by providing an articulating wrist mechanism which provides a sharp bending radii solution whilst also allowing for high force transmission via a mechanically constrained tip. The instrument according to various embodiments therefore represents a significant improvement compared with conventional instruments.

[0077] According to various embodiments an instrument is provided which utilises a spherical buttress (or concave-convex abutment interface) at the instrument tip together with actuating tendons which are provided in order to transmit forces. Direct actuation of the instrument tip via the tendons increases the signal-to-noise ratio of the force transmission thereby enabling more precise quantitative force measurements. It will be appreciated by those skilled in the art that this represents a significant benefit.

[0078] Further, the design of the instrument according to various embodiments which eliminates a central pin mechanism (as may be found in conventional arrangements) combined with the elimination of open slotted necks facilitates an internal cannulation or other fluid channel which may be utilised to serve as a suction and / or irrigation channel.

[0079] Accordingly, the actuated wrist mechanism according to various embodiments represents a significant advance in the art.

[0080] BRIEF DESCRIPTION OF THE DRAWINGS

[0081] Various embodiments will now be described, by way of example only, together with arrangements given for illustrative purposes and with reference to the accompanying drawings in which:

[0082] Fig 1. shows a conventional curved wrist joint and a conventional pin wrist joint;

[0083] Fig. 2 shows a cut-away view of an actuated wrist mechanism which is shown abutting against a portion of a surgical tool according to various embodiments and which shows, in particular, how the spherical end portions of tendons may be received within corresponding recesses or sockets which may be provided within a plate which form part of the surgical tool; Fig. 3 shows a side view of an actuated wrist mechanism according to various embodiments, wherein the actuated wrist mechanism is shown having a concave abutment surface which abuts against a corresponding convex abutment surface of the surgical tool, and wherein one of four grooves which run along at least a portion of the shaft which forms a component of the actuated wrist mechanism is shown;

[0084] Fig. 4 shows a cross-sectional view of an actuated wrist mechanism comprising a shaft according to various embodiments, wherein the actuated wrist mechanism is shown positioned in an abutted relationship against a surgical tool comprising a pair of scissors, wherein a first pair of tendons are shown being received within end portions of the blades forming the pair of scissors so that the first pair of tendons may be actuated in order to operate the scissors and wherein a second pair of tendons are shown being received within an end portion of the surgical tool and wherein the second pair of tendons may be actuated in order cause the surgical tool to move (e.g. rotate, pitch, yaw or swivel) relative to the end of the actuated wrist mechanism;

[0085] Fig. 5 shows a front view a plate which forms a portion of a surgical tool and shows a plurality of recesses or sockets into which the end portions of tendons may be received, it being noted that the tendons are not actually shown but access ports through which the tendons extend are shown together with a central cannula or fluid flow channel;

[0086] Fig. 6 shows a similar view to Fig. 5 but with the end portions of the tendons being shown as being present and shows how the end portions of the tendons are received within recesses or sockets provided in plate of the surgical tool, and wherein the tendons extend through the access ports;

[0087] Fig. 7 shows a rear view of the plate of the surgical tool according to various embodiments and show apertures or ports provided in the plate through which tendons may extend;

[0088] Fig. 8 shows another rear view showing a portion of the shaft of the actuated wrist mechanism abutting against an end portion of the surgical tool and wherein tendons having end portions are received within recesses or sockets provided within a plate which forms part of the surgical tool, wherein actuation of the tendons will cause movement of the surgical tool relative to the end portion of the actuated wrist mechanism according to various embodiments;

[0089] Fig. 9 shows further embodiments a surgical tool may be attached to the actuated wrist mechanism via tendons which are capable of supplying electrical power to at least a portion of the surgical tool; Fig. 10 shows embodiments wherein the tendons may comprise braided metallic cables with an electrically insulating sheath which may be utilised to supply electrical power to an attached surgical tool;

[0090] Fig. 11 shows a prior art surgical instrument with pivoting serrated jaws at the distal end of an elongate shaft for minimally invasive tissue manipulation;

[0091] Fig. 12 shows a prior art surgical instrument with an elongate shaft and opposed serrated jaws;

[0092] Fig. 13 shows various prior art surgical instruments with different jaw shapes and configurations at the distal end of an elongate shaft for specific surgical applications;

[0093] Fig. 14 shows a robotic surgical tool assembly with an elongate shaft, articulated end effector, opposed jaws and a compact actuation mechanism with gear sets and linkages for robotic control;

[0094] Fig. 15 shows a robotic surgical tool according to an embodiment with an elongate shaft, distal gripper unit, proximal drive interface, pivoting jaws and tension cables for actuating the gripper and wrist joint;

[0095] Fig. 16 shows a robotic surgical tool with an articulated wrist joint and distal gripper, tension cable actuation and a compact ball joint mechanism for multi-axis articulation;

[0096] Fig. 17 shows a robotic surgical tool with an elongate shaft, distal end effector in the form of opposed jaws, wrist joint for angular articulation and proximal drive system connection;

[0097] Fig. 18 shows a robotic surgical tool interface assembly with an oval connector layout, multiple circular ports, and a mechanical housing with internal drive pulleys and shafts for actuating the tool;

[0098] Fig. 19 shows a bearing and joint assembly for a robotic surgical tool, including engineering drawings of cylindrical bearing housings, ball joint structure, and a CAD rendering of a drive housing with pulleys;

[0099] Fig. 20 shows a drive module for a robotic surgical tool with multiple pulley wheels and cable routings and a compact housing for precise motion transfer to the distal end effector; Fig. 21 shows a robotic surgical wrist mechanism with proximal drive layout for multiple degrees of articulation and a distal wrist joint with a spherical element and cable guides;

[0100] Fig. 22 shows robotic surgical tools with an articulated wrist mechanism, including a curved electrosurgical tip and a pair of opposed jaws, each with a spherical wrist joint and cable-driven actuation system;

[0101] Fig. 23 shows a robotic surgical tool with an articulated wrist joint and distal grasper, illustrating jaws in open and closed positions and enlarged detail of the distal end;

[0102] Fig. 24 shows an experimental assembly of a cable-driven surgical tool with a proximal actuation housing, elongate shaft and distal grasper actuated by control cables;

[0103] Fig. 25 shows a prototype cable-driven robotic surgical tool and corresponding CAD model, with an elongate shaft, distal grasper and circular drive plate for cable actuation;

[0104] Fig. 26 shows detailed CAD views of a robotic surgical tool, including a proximal drive housing with pulleys and a distal gripper component with cable-actuated jaws;

[0105] Fig. 27 shows a distal tool assembly with integrated suction and electrical connection features, including a CAD rendering of the tip housing and schematic internal arrangement;

[0106] Fig. 28 shows a further view of the distal tool assembly, highlighting the housing structure and integration of suction, electrical, and cable actuation features;

[0107] Fig. 29 shows a surgical handpiece and distal actuation mechanism, with a proximal interface plate for connections and a cutaway of the distal jaw mechanism with spherical and pin joints;

[0108] Fig. 30 shows detailed views of a distal surgical tool jaw assembly, including a cutaway model with internal actuation elements and an isolated jaw housing;

[0109] Fig. 31 shows detailed views of a distal jaw actuation mechanism, including cable connections, spherical joints and sectional illustrations of the jaws in open position;

[0110] Fig. 32 shows sectional and assembled views of a distal end effector mechanism, with cable routing, spherical joints, and longitudinal sections of the jaw housing; Fig. 33 shows perspective views of a distal jaw assembly, illustrating jaws in open and closed positions and the internal cable-driven mechanism;

[0111] Fig. 34 shows a physical prototype of a cable-driven surgical tool, with a proximal housing, elongate shaft, and distal grasper actuated by cables;

[0112] Fig. 35 shows detailed photographs of the distal end of a prototype cable-driven grasper, with jaws in partially open and open positions and visible cable terminations;

[0113] Fig. 36 shows further views of the distal grasper of a cable-driven surgical tool prototype, with jaws in nearly closed and open positions, visible pivot mechanism and cable attachments;

[0114] Fig. 37 shows a prototype surgical tool assembly;

[0115] Fig. 38 shows further views of the prototype surgical tool;

[0116] Fig. 39 shows sectional and perspective views of a distal scissor-type end effector, illustrating internal jaw configuration, actuation linkages, and design refinements such as tip profile and suction channel;

[0117] Fig. 40 shows design refinements for a distal scissor-type end effector, including side and sectional views, jaw profiles, suction venting channels and articulation features;

[0118] Fig. 41 shows multiple views of a distal end effector according to an embodiment;

[0119] Fig. 42 shows views of an electrosurgical instrument tip with jaw actuation and electrical conduction features according to an embodiment;

[0120] Fig. 43 shows perspective and side views of the proximal housing of the surgical instrument according to an embodiment;

[0121] Fig. 44 shows detailed views of the proximal housing assembly according to an embodiment;

[0122] Fig. 45 shows integration of the drive motor assembly within the proximal housing, with sectional views of the motor, coupling elements and structural support for torque delivery;

[0123] Fig. 46 shows the motor and drive assembly enclosed within the proximal housing, with sectional and perspective views highlighting the integration and alignment of internal components; Fig. 47 shows structural integration of the proximal motor housing with external support and alignment frames, including perspective views of the assembled enclosure and support brackets;

[0124] Fig. 48 shows the enclosure and integration of the motor drive unit within a protective housing, with sectional and perspective views of the internal layout and external cover;

[0125] Fig. 49 shows external and sectional features of the motor housing assembly, including cross-section of internal structural components and perspective view of the external cover;

[0126] Fig. 50 shows external and sectional details of the motor housing and internal drive assembly, including a close-up of the outer casing and a sectional cutaway of the internal mechanism;

[0127] Fig. 51 shows a combination of motor drive integration and detailed jaw assembly views, including a sectional cutaway of the motor housing and various jaw orientations;

[0128] Fig. 52 shows the detailed structure and scale of the end-effector jaw assembly, with perspective, front, and scale comparison views;

[0129] Fig. 53 shows a jaw assembly according to various embodiments;

[0130] Fig. 54 shows dimensional and geometric characteristics of the instrument tip together with its integration into the shaft and drive housing, and an exploded perspective view of the assembly according to an embodiment;

[0131] Fig. 55 shows diagrams of mechanical forces acting on the jaw mechanism, with geometry, trigonometry, and force resolution for actuation and tissue engagement;

[0132] Fig. 56 shows a sequence of assembly steps for the housing and internal components of the device, with images of modular parts and cover alignment;

[0133] Fig. 57 shows the design and specification of a flexible segment assembly, showing both structural arrangement and engineering dimensions, including cable routing and articulation;

[0134] Fig. 58 shows anatomical access pathways and working envelopes relevant to the deployment of the instrument in joint surgery, with overlays of angular ranges and clinical reference images; and Fig. 59 shows the surgical workspace and clinical applicability of the instrument in relation to shoulder anatomy and arthroscopic procedures, with overlays of tool trajectories and clinical reference material.

[0135] DETAILED DESCRIPTION

[0136] As background to various embodiments, an overview of the types of conventional wrist joints commonly used in surgical instruments will be briefly given. Conventional wrist joints are designed to provide articulation at the distal end of an instrument, thereby enabling the surgeon to access and manipulate tissue in confined or anatomically complex spaces. However, these known wrist joint mechanisms each have inherent limitations in terms of dexterity, strength, and suitability for miniaturisation.

[0137] Two types of conventional wrist joint will first be discussed briefly below.

[0138] Fig. 1 shows a conventional curved wrist joint 100 which uses a series of interconnected segments that can be manipulated to bend the instrument’s tip in various directions, approximating an arc. This type of joint is often referred to as a “curved” or “vertebral” wrist, and is typically actuated by tensioning cables or similar mechanisms that cause the segments to articulate relative to one another. The curved wrist joint provides a smooth, continuous range of motion and is well suited for applications where gentle, sweeping movements are required. However, the structure of interconnected segments can limit the amount of force that can be transmitted to the instrument tip, and the overall assembly may be relatively bulky, making miniaturisation challenging.

[0139] Fig. 1 also shows a pin wrist joint 101, which comprises a central pin that allows the instrument’s tip to pivot or rotate around it, thereby offering a sharp bend. This “pin” or “hinge” type wrist joint provides a more abrupt change in direction at the distal end of the instrument, enabling the tip to be positioned at a significant angle relative to the shaft. The pin wrist joint is generally simpler in construction than the curved wrist joint and can provide a high degree of angular articulation. However, the use of a central pin as the pivot point can introduce mechanical weaknesses, limit the range of motion to a single plane, and restrict the ability to integrate additional features such as suction or irrigation channels.

[0140] These conventional wrist joint designs, while providing some degree of articulation, are subject to various trade-offs in terms of dexterity, strength, and integration with other instrument functions. The present invention seeks to address these limitations by providing an improved actuated wrist mechanism that combines robust force transmission, enhanced manoeuvrability, and suitability for miniaturisation, as will be described in detail below. The arrangements shown in Fig. 1 and in particular the limitations of the arrangements have been discussed in detail above. In particular, the conventional arrangements which are shown in Fig. 1 limit the dexterity of a surgeon and are not suitable for transmitting high forces. As such, the known arrangements have limited usefulness.

[0141] Furthermore, as is apparent from Fig. 1 and as will be understood by those skilled in the art, the known arrangements are relatively complex, expensive to manufacture and are not suited to miniaturisation.

[0142] An instrument according to various embodiments will now be discussed in more detail below. The instrument according to various embodiments comprises a tendon- driven ball on plate mechanism which is designed to buttress forces during arthroscopic procedures with a constraint instrument tip. The ball on plate solution provides a robust structure which can withstand forces from multiple directions at up to ± 90 degrees pitch and yaw thereby addressing various limitations of conventional arrangements.

[0143] It will be understood that the instrument according to various embodiments which is disclosed in more detail below enables a surgeon to perform highly dexterous procedures involving the transmission of significant force to the surgical tool. It has been found that the instrument is beneficially significantly more robust and easier to manipulate than conventional arrangements.

[0144] Fig. 2 shows an isometric view of an end portion of an actuated wrist mechanism 200a according to various embodiments which is shown being in an abutted relationship with an end portion of a surgical tool 200b. The actuated wrist mechanism 200a comprises four tendons 215a, 215b, 215c, 215d (only portions of which are shown for ease of understanding) and which each have end portions 205a, 205b, 205c, 205d which are received within recesses or sockets provided in an end portion or plate which forms a component of the surgical tool 200b. It will be understood that according to various embodiments one, two, three, four, five, six, seven, eight, nine, ten or more than ten tendons may be provided. The four tendons 215a, 215b, 215c, 215d shown in Fig. 2 and subsequent figures are for illustrative purposes only. As will be explained in more detail, tendons can be used for different purposes such as manipulating the angle or position of the surgical tool 200b and / or also controlling the operation of the surgical tool 200b e.g. causing one component of the surgical tool 200b, such as a knife blade, to move relative to the main body of the surgical tool 200b.

[0145] The tendons 215a,215b,215c,215d may be actuated by one or more motors (not shown) and may configured to control the movement and / or operation of the surgical tool 200b. A control system may be provided (not shown) to control the operation of the motors and hence the tendons 215a, 215b, 215c, 215d. The control system may comprise a component of a robot or robotic system. In particular, the control system may form part of a surgical robot or surgical robotic system.

[0146] As will be understood by those skilled in the art, the tendons 215a, 215b, 215c, 215d are configured to transmit force(s) to the surgical tool 200b and may be made of a material such as a metal, plastic or carbon fibre which is robust and capable of transmitting force without suffering from damage. The actuated wrist mechanism 200a may comprise a connection or abutment portion which is configured to connect or abut to the surgical tool 200b. In particular, the connection or abutment portions may comprise a concave-convex interface or more generally a spherical or semi-spherical interface. The surgical tool 200b may comprise an instrument tip in the form of a plate 218 which has a plurality of recesses or sockets formed within the plate 218. The end portion 205a, 205b, 205c, 205d of each tendon 215a, 215b, 215c, 215d may be received in a respective recess or socket formed in the plate 218.

[0147] In the particular mode of operation shown in Fig. 2, the tendons 215a, 215b, 215c, 215d may be configured to move the surgical tool 200b by, for example, causing the surgical tool 200b to move, rotate, pitch, roll or yaw relative to the end of the actuated wrist mechanism 200a. However, as will be more apparent below, at least some or each end portion 205a, 205b, 205c, 205d may also be movable between a first position wherein the end portion 205a, 205b, 205c, 205d is at least partially received within the one or more recesses of the plate 218 as shown in Fig. 2 and a second position wherein the end portions 205a, 205b, 205c, 205d extend beyond the plate 218 so that the end portions 205a, 205b, 205c, 205d are no longer fully received within a recess of the plate 218 but instead are engaged with an operational portion of the surgical tool 200a such as the blade of a knife or a pair of scissors (not shown).

[0148] The actuated wrist mechanism 200a may comprise a shaft having a shaft collar 214, wherein the shaft further comprises a plurality of tendon guides or shafts 212, one for each tendon. Fig. 2 only shows a single tendon guide or shaft 212 but it will be understood that three further tendon guides or shafts may be provided (one for each tendon) but that these are not visible in Fig. 2. It will also be understood that one of the advantages of adopting an arrangement of a plurality tendons 215a,215b,215c,215d received in a plurality of recesses or sockets which may be disposed, as shown in Fig. 2, around the periphery of a plate 218 is that such an arrangement allows a central suction and irrigation channel 201 to be provided. The end portions of the tendons 205a, 205b, 205c, 205d may also be referred to as bollards and with this in mind the arrangement shown in Fig. 2 may be considered as comprising a pitch up bollard 205a, a yaw left bollard 205b, a pitch down bollard 205c and a yaw right bollard 205d. With reference to Fig. 2 it will be understood that the instrument tip or plate 218 is effectively positively actuated by tendons 215a, 215b, 215c, 215d which may be connected to motors (not shown) which may be capable of transmitting force to the tendons 215a, 215b, 215c, 215d. An electromotive force measurement device may be provided to monitor any back electromotive force (“EMF”) experienced by the motors and which is indicative either: (i) of force(s) applied by the tendons 215a, 215b, 215c, 215d to the surgical tool 200b; and / or (ii) any force(s) experienced by the surgical tool 200b from the external environment.

[0149] It will be understood that the surgical tool 200b may be driven by motors (not shown) which actuate the various tendons 215a, 215b, 215c, 215d which engage with an end portion of the surgical tool 200b which abuts against a corresponding end portion of a shaft having a shaft collar 214 thereby enabling the surgical tool 200b to roll and make pitch and / or yaw movements amongst others. A device may be provided to measure the back electromotive force (“EMF”) experienced by the one or motors and measurement of the back electromotive force may be used to determine the forces exerted by and on the surgical instrument or surgical tool 200b. As a result, real-time quantitative feedback can be provided to the surgeon or other user.

[0150] The cannulated nature of the present design allows for the integration of one or more suction and irrigation channels enabling fluid management at the instrument tip e.g. to capture tissue, suture or provide a clear surgical field. In the particular embodiment shown in Fig. 2 a single central cannula or fluid flow channel 201 is shown but it will be understood that other embodiments are contemplated wherein one or more cannulas or other suction and / or irrigation channels may be provided. In particular, the one or more suction and / or irrigation channels do not have to be provided centrally but can alternatively or in addition be provided around the periphery of the plate 218. For example, an embodiment is contemplated wherein suction / irrigation channels may be centered at approximately the same radius from the centre of plate 218. For example, one or more recesses may be provided which are centred at a radial distance from the centre of plate 218 and one or more suction / irrigation channels may be provided which are centred at a radial distance r2 from the centre of plate 218. According to various embodiments, < r2. According to other embodiments n = r2. According to yet further embodiments > r2.

[0151] According to various embodiments an actuated wrist mechanism 200a as shown in Fig. 2 is disclosed which is configured to control the movement and / or operation of a surgical tool 200b which is attached, in use, to the actuated wrist mechanism 200a. It will also be understood that more generally the surgical tool 200b may be replaced by an attachment which is desired to be moved and / or operated in a similar manner. The actuated wrist mechanism 200a may comprise a shaft portion which may comprise a shaft collar 214. The shaft collar 214 may comprise a first abutment surface (which will be described in more detail below) and which is configured to abut, in use, against an abutment surface 213 of a surgical tool 200b. The shaft portion may further comprise one or more grooves 212 which are configured to allow one or more tendons 215a, 215c, 215d to lie flush with or along the length of the shaft along the axial length of the shaft. According to an embodiment one tendon 215a;215b;215c;215d may be arranged in one of the one or more grooves 212. However, alternative arrangements are contemplated wherein multiple tendons may be provided in the same groove. Embodiments are also contemplated wherein tendons may be channeled through one or more common grooves or channels and then split into separate channels or grooves towards the distal end of the shaft and the abutment surface of the shaft. Each tendon 215a, 215b, 215c, 215d may comprise an end portion 205a, 205b, 205c, 205d which may comprise a spherical end portion or other shape. The end portions 205a, 205b, 205c, 205d may form bollards at the end of each tendon

[0152] 215a, 215b, 215c, 215d. It will be understood that in use the one or more of the tendons 215a, 215b, 215c, 215d may be configured to control the movement and / or operation of the surgical tool 200b. One or more actuators such as motors (not shown) may be provided for actuating the one or more tendons 215a,215b,215c,215d. Accordingly, various embodiments relate to the combination of an actuated wrist mechanism 200a as described above and a surgical tool 200b (or other attachment) which may be abutted against the actuated wrist mechanism 200a.

[0153] The arrangement illustrated in Fig. 2 provides several significant advantages over conventional systems. Firstly, the use of multiple tendons, each with an end portion received in a corresponding recess or socket of the surgical tool, enables highly precise and controlled actuation of the tool. This configuration allows for fine manipulation of the tool’s position and orientation, including pitch, yaw, roll, and combinations thereof, thereby greatly enhancing dexterity and enabling the surgeon to perform complex tasks in confined anatomical spaces.

[0154] The abutment interface, such as a concave-convex or spherical arrangement, between the actuated wrist mechanism and the surgical tool ensures stable alignment and robust force transmission. This reduces mechanical play and increases the reliability of the system, allowing for consistent and repeatable tool movements. The arrangement also supports positive actuation, meaning that the tool’s movement is directly and actively controlled by the tendons and motors, rather than relying on passive or springbased mechanisms.

[0155] The modularity of the design, with tendons and sockets distributed around a plate, allows for the integration of a central cannula or fluid flow channel. This enables the provision of suction and / or irrigation directly at the instrument tip, supporting effective fluid management, tissue capture, and maintenance of a clear surgical field. The ability to provide one or more fluid channels, either centrally or peripherally, further increases the versatility of the instrument and reduces the need for additional devices in the surgical field.

[0156] The system is also well suited to miniaturisation, as the elimination of bulky linkages and the use of slender tendons and compact abutment surfaces allow the mechanism to be scaled down for minimally invasive procedures. The reduced complexity and number of moving parts improve reliability, ease of assembly, and maintenance, while also lowering the risk of mechanical failure.

[0157] Furthermore, the arrangement is compatible with advanced control systems, including robotic actuation and real-time force feedback via back electromotive force (EMF) measurement. This enables quantitative monitoring of the forces applied to and experienced by the surgical tool, providing valuable feedback to the surgeon and supporting safer, more effective procedures.

[0158] Overall, the actuated wrist mechanism and surgical tool combination described in Fig. 2 delivers enhanced precision, dexterity, robustness, and integration of auxiliary functions, representing a substantial improvement over prior art arrangements.

[0159] Fig. 3 shows a side view of an actuated wrist mechanism 200a and the end portion of an attached surgical tool 200b according to various embodiments. The actuated wrist mechanism 200a comprises a shaft having a shaft collar 214 which may comprise a concave (or other shaped) abutment surface 213 which abuts against a corresponding convex (or other shaped) abutment surface of the surgical tool 200b. Three (out of four) tendons 215a,215c,215d are shown wherein each tendon 215a, 215c, 215d comprises an end portion or bollard 205a, 205c, 205d. Each end portion or bollard 205a, 205c, 205d of each tendon 215a, 215c, 215d is received within a recess or socket formed in a plate 218. In Fig. 3 a tendon 215a for moving the surgical tool 200b in a pitch up direction is shown, together with a tendon 215c for moving the surgical tool in a pitch down direction and a tendon 215d for moving the surgical tool 200b in a yaw right direction. A tendon for moving the surgical tool 200b in a yaw left direction is not visible. The shaft of the actuated wrist mechanism 200a may be provided with a plurality of longitudinal or axial grooves or channels. A groove or channel 212 for the tendon 215d which may be actuated in order to move the surgical tool 200b in a yaw right direction is shown. A shaft connection groove 235 is also shown.

[0160] The arrangement shown in Fig. 3 offers several advantages. The use of a concave (or other shaped) abutment surface on the shaft collar of the actuated wrist mechanism, abutting against a corresponding convex (or other shaped) abutment surface of the surgical tool, provides a stable and robust interface that facilitates smooth articulation and precise alignment between the wrist mechanism and the tool. This configuration minimises play and ensures reliable force transmission during operation. The provision of multiple tendons, each terminating in a bollard received within a dedicated recess or socket in the tool’s plate, enables highly controlled and independent actuation in multiple directions, such as pitch and yaw. This allows the surgical tool to be manipulated with a high degree of dexterity, supporting complex movements and fine adjustments within confined anatomical spaces. The arrangement also allows for the possibility of simultaneous multi-axis articulation, further enhancing the surgeon’s ability to access and treat difficult-to-reach areas.

[0161] Additionally, the inclusion of longitudinal or axial grooves or channels in the shaft for guiding the tendons ensures that the tendons are securely routed and protected along the length of the instrument. This not only improves the reliability and durability of the mechanism but also supports miniaturisation by allowing the tendons to be neatly integrated within a slender shaft profile

[0162] Fig. 4 shows a cross-sectional view of an actuated wrist mechanism 200a according to various embodiments attached to a surgical tool 200b which comprises a pair of scissors. The actuated wrist mechanism 200a comprises a shaft having a shaft collar 214 and includes a central suction and irrigation channel 201. As is evident from Fig. 4 the shaft may comprise a concave buttressing or abutment surface 216 which abuts against a corresponding convex buttressing or abutment surface 213 of the surgical tool 200b. A first pair of tendons namely a pitch up tendon 215a having a pitch up end portion or bollard 205a and a pitch down tendon 215c having a pitch down end portion or bollard 205c are provided and engage with a plate 218 of the surgical tool 200b so as to provide directional control of the surgical tool 200b. In particular, the pair of tendons 215a, 215c and associated end portions or bollards 205a, 205c are used to move the surgical tool 200b which includes a pair of scissors in a pitch up or pitch down direction. A second pair of tendons are shown having end portions which are engaged with a movable blade of a pair of scissors. According to various embodiments the movable blade may be rotated or otherwise rotated relative to a second blade which may be fixed. Actuation of the associated tendons causes the pair of scissors to open or close thereby enabling tissue to be cut by the pair of scissors in a cutting motion.

[0163] As can be seen from Fig. 4, the shaft may comprise a first abutment surface 216 which may comprise a concave abutment surface and surgical tool 200b (or other attachment) may comprise an abutment surface 213 which may comprise a convex abutment surface. Alternatively, the first abutment surface 216 may comprise a convex abutment surface and the abutment surface of the surgical tool 200b (or other attachment) may comprise a concave abutment surface. It will be understood that the surgical tool 200b (or other attachment) and the actuated wrist mechanism 200a may form a ball and socket arrangement or interface. As explained above, a surgical tool 200b such as a pair of scissors as shown in Fig. 4 or more generally another surgical tool or other attachment may be operated by actuating one or more of the tendons 215a, 215c. It will be understood that the tendons 215a, 215c are capable of transmitting mechanical force and may be extended and / or withdrawn by motors (not shown). As such, the actuated wrist mechanism 200a according to various embodiments enables an attachment such as a surgical tool 200b to be moved in terms of pitch up and / or pitch down motion. The attachment may also be moved in terms of yaw left and / or yaw right. Furthermore, the attachment may be moved so as to roll or rotate in a first direction and / or a second direction. For example, the first direction may be clockwise and the second direction may be opposed to the first direction (e.g. may be anticlockwise). Accordingly, the surgical tool 200b or other attachment is configured to be positively actuated by the one or more tendons 215a, 215c. The one or more tendons 215a, 215c are thus connected to one or more motors, wherein the one or more motors are configured to transmit force to the surgical tool 200b (or other attachment) via the one or more tendons 215a, 215c.

[0164] A particularly advantageous aspect of various embodiments is that a force measuring device may be provided (not shown) which may be configured to measure the force transmitted to the surgical tool 200b (or other attachment) via the one or more tendons 215a,215c. For example, embodiments are contemplated wherein the force measuring device is configured to measure a back electromotive force (“EMF”) experienced by the one or more motors, wherein the measured back electromotive force correlates with the force(s) exerted on the surgical tool 200b and / or experienced by the surgical tool 200b.

[0165] The arrangement shown in Fig. 4 provides several notable advantages. The use of a concave abutment surface on the shaft collar of the actuated wrist mechanism, abutting against a corresponding convex abutment surface of the surgical tool, creates a stable and robust interface that supports smooth articulation and precise alignment between the wrist mechanism and the tool. This configuration minimises mechanical play and ensures reliable force transmission, which is essential for controlled and repeatable tool movements.

[0166] The provision of multiple tendons, each terminating in a bollard received within a dedicated recess or socket in the tool’s plate, enables highly controlled actuation in multiple directions. This allows the surgical tool, such as a pair of scissors, to be manipulated with a high degree of dexterity, supporting complex movements such as pitch, yaw, and roll, as well as the opening and closing of the scissor blades. The ability to independently actuate different tool components enables the surgeon to perform intricate tasks with greater precision and efficiency. The inclusion of a central suction and irrigation channel within the shaft allows for integrated fluid management at the instrument tip, facilitating the removal of debris and maintenance of a clear surgical field without the need for additional instruments. This integration improves procedural efficiency and reduces clutter in the surgical workspace. Furthermore, the system is compatible with advanced control and feedback mechanisms, such as force measuring devices that monitor back electromotive force (EMF) in the motors. This enables real-time quantitative feedback on the forces applied to or experienced by the surgical tool, enhancing safety and providing valuable information for intraoperative decision-making.

[0167] Fig. 5 shows a front view of a plate 218 of a surgical tool 200b according to various embodiments with the tendons absent. A central suction and irrigation channel 201 is shown. The plate 218 comprises a first recess or pitch up bollard hub 220a which is arranged to receive the end portion or bollard of a pitch up tendon (not shown). The plate 218 further comprises a second recess or yaw left bollard hub 220b which is arranged to receive the end portion or bollard of a yaw left tendon (not shown), a third recess or pitch down bollard hub 220c which is arranged to receive the end portion or bollard of a pitch down tendon (not shown) and a fourth recess or yaw right bollard hub 220d which is arranged to receive the end portion or bollard of a yaw right tendon (not shown).

[0168] Centrally located within the plate 218 is a suction and irrigation channel 201 , which is configured to allow fluid management directly at the instrument tip. The plate 218 is provided with a series of recesses or hubs, each designed to receive the end portion or bollard of a corresponding tendon. Specifically, the plate includes a first recess or pitch up bollard hub 220a for a pitch up tendon, a second recess or yaw left bollard hub 220b for a yaw left tendon, a third recess or pitch down bollard hub 220c for a pitch down tendon, and a fourth recess or yaw right bollard hub 220d for a yaw right tendon. This arrangement offers several advantages. By distributing the recesses around the periphery of the plate, the design allows for precise and independent control of the surgical tool’s movement in multiple directions, including pitch and yaw. The central positioning of the suction and irrigation channel ensures that fluid management can be performed efficiently without interfering with the actuation mechanism or the structural integrity of the tool. The separation of the tendon attachment points from the fluid channel also minimises the risk of cross-contamination and mechanical interference. Furthermore, the modular nature of the plate, with dedicated hubs for each tendon, supports a high degree of customisability and scalability. Additional recesses can be incorporated to accommodate more tendons if required, enabling even greater dexterity and control. The design also facilitates straightforward assembly and maintenance, as each tendon can be individually installed or replaced without disturbing the other components. Fig. 6 shows a front view of a plate 218 of a surgical tool 200b according to various embodiments with the tendons 215a, 215b, 215c, 215d shown being present. A central suction and irrigation channel 201 is also shown. The plate 218 comprises a first recess or pitch up bollard hub which receives the end portion or bollard 205a of a pitch up tendon 215a. The plate 218 further comprises a second recess or yaw left bollard hub which is arranged to receive the end portion or bollard 205b of a yaw left tendon 215b, a third recess or pitch down bollard hub which is arranged to receive the end portion or bollard 205c of a pitch down tendon 215c and a fourth recess or yaw right bollard hub which is arranged to receive the end portion or bollard 205d of a yaw right tendon 215d.

[0169] According to various embodiments the end portion of each tendon may comprise a ball or a substantially spherical object. Accordingly, the plate 218 with recesses may form a ball-on-plate arrangement. However, other embodiments are also contemplated wherein the end portions of at least some of the tendons form a different type of connection with the plate 218. For example, the end portion of at least some of the tendons may comprise a plug mechanism which is received within a socket provided in the plate 218. Alternatively, the plate 218 may comprise one or more plugs and the end portion of at least some of the tendons may comprise a socket which engages with a plug on the plate 218.

[0170] An advantage of the arrangement shown in Fig. 6 is that it enables secure and precise engagement between the tendons and the surgical tool, allowing for highly controlled and responsive actuation in multiple directions. The use of spherical or ballshaped end portions received within dedicated recesses or hubs on the plate 218 facilitates smooth articulation and minimises mechanical play, resulting in accurate and repeatable movements of the tool tip. This ball-on-plate or alternative plug-and-socket configuration also allows for efficient force transmission from the tendons to the tool, enhancing both dexterity and robustness. Furthermore, the central suction and irrigation channel can operate independently of the tendon actuation, ensuring effective fluid management without compromising the mechanical performance of the instrument. Overall, this design supports complex manoeuvres, improves reliability, and is well suited for minimally invasive surgical procedures requiring both fine control and integrated auxiliary functions.

[0171] A person skilled in the art will appreciate that an actuated wrist instrument according to various embodiments is a specialised tool which is designed to enhance the precision and dexterity of surgeons during minimally invasive procedures, particularly arthroscopy. This instrument is constructed with several key components that enable it to perform complex manoeuvres within the tight confines of a joint. The instrument may comprise a handle which a surgeon may grip and which enables the surgeon to control and manipulate the instrument’s movements. The instrument may comprise a shaft which is connected to the handle and which is designed for insertion through small incisions thereby minimising tissue damage and promoting quicker recovery of the patient. The actuated wrist instrument allows the instrument’s tip to move in multiple directions in a flexible manner.

[0172] The tip of the instrument may be fitted with various tools such as scissors which may be tailored to the specific needs of the procedure. The control mechanism, whether mechanical or robotic, enables the surgeon to make fine adjustments to the tip’s position and orientation, ensuring precise manipulation of tissues within the joint.

[0173] The actuated wrist instrument according to various embodiments allows a surgeon to diagnose and treat joint problems with a high degree of accuracy. For instance, during a knee arthroscopy, the instrument might be used to visualise the interior of the joint, grasp and remove damaged tissue or precisely suture torn ligaments. The enhanced manoeuvrability provided by the actuated wrist means that these tasks can be performed with minimal invasiveness, reducing patient trauma and accelerating recovery times.

[0174] The actuated wrist instrument according to various embodiments represents a significant advance in the art and empowers surgeons to perform intricate procedures with greater ease and improved patient outcomes.

[0175] It will be understood that with conventional instruments a source of surgical error (e.g. unintended tissue damage) may relate to the lack of mechanical feedback and surgeon control. The forces applied during surgical tasks such as suturing have been shown to significantly affect patient outcomes but are largely unknown during the procedure when using a conventional instrument. There is currently no way for a surgeon to quantitively gauge the forces applied to a surgical instrument during surgery.

[0176] Accordingly, it will be recognised that the actuated wrist instrument according to various embodiments provides a high degree of mechanical feedback and in particular the force applied by the instrument whilst performing a surgical task can be recorded.

[0177] It will also be understood that the quality of the tissue cut achieved via a cutting instrument such as a punch or shaver affects the prognosis of the surgical outcome but is limited by access issues. A stiff straight shaft cannot sufficiently provide access to all locations of the joint due to the complex curvature of the local anatomy, which requires high angulation over small radii compared to the total length of the instrument. Current instruments either lack dexterity- promoting features or strength features. By way of contrast, an actuated wrist instrument according to various embodiments possesses both distal tip mechanisms which allows the surgeon to reposition the instrument tip during use whilst at the same time providing a sufficiently high loadbearing capacity as needed for surgery.

[0178] The instrument according to various embodiments seeks to address the limitations of current arthroscopic instruments by introducing a novel articulating wrist design which provides sharp bending radii while also allowing for high force transmission via a mechanically constrained tip.

[0179] The instrument utilises both a spherical buttress at the instrument tip and actuating tendons to transmit forces. Direct actuation of the instrument tip via the tendons increases the signal-to-noise ratio of the force transmission, enabling more precise quantitative force measurements.

[0180] The elimination of a central pin mechanism combined with the elimination of open slotted necks facilitates an internal cannulation to be included which can serve as a suction and irrigation channel.

[0181] Fig. 7 shows a rear view of a portion of a portion of a surgical tool 200b according to various embodiments and shows an abutment surface 213 of a plate 210. Ports, openings or access apertures 200a, 220b, 220c, 220d are also shown through which a tendon may be pass so that an end portion of the tendon is received in a recess on the other side of the plate 210. A central suction and irrigation channel 201 is also shown.

[0182] In particular, Fig. 7 highlighting the abutment surface 213 of a plate 210. The figure illustrates several ports, openings, or access apertures 200a, 220b, 220c, 220d, each of which is configured to allow a tendon to pass through the plate so that the end portion of the tendon can be received in a corresponding recess or socket on the opposite side of the plate 210. A central suction and irrigation channel 201 is also depicted, running through the plate to facilitate fluid management at the instrument tip.

[0183] This arrangement provides several advantages. By positioning the access apertures around the periphery of the plate, the design allows for the tendons to be routed efficiently and securely, reducing the risk of entanglement or interference with other components. The clear separation between the tendon pathways and the central suction and irrigation channel ensures that both mechanical actuation and fluid management can be performed independently and without compromise. This is particularly beneficial in minimally invasive procedures, where space is limited and the integration of multiple functionalities within a compact form factor is essential. Furthermore, the rear view of the plate demonstrates the modularity and accessibility of the design. The ports and apertures are sized and positioned to facilitate straightforward assembly and maintenance, allowing tendons to be easily installed, replaced, or adjusted as needed. This not only improves the reliability and longevity of the instrument but also reduces downtime and complexity during surgical preparation and instrument servicing.

[0184] The inclusion of a central suction and irrigation channel, in combination with the distributed tendon access points, enables the surgical tool to maintain a clear operative field while simultaneously providing precise and dexterous control of the instrument tip. This dual functionality enhances the surgeon’s ability to perform complex tasks efficiently and safely, ultimately contributing to improved clinical outcomes and patient care.

[0185] Fig. 8 shows how the tendons 215a,215b,215c,215d interact with an actuated wrist mechanism 200a according to various embodiments. The actuated wrist mechanism 200a may comprise a shaft collar 214 and may include a central suction and irrigation channel 201. The actuated wrist mechanism 200a comprises a first (pitch up) tendon 215a and associated tendon guide 209a, a second (yaw left) tendon 215b and associated tendon guide 209b, a third (pitch down) tendon 220c and associated tendon guide 209c, and a fourth (yaw right) tendon 220d and associated tendon guide 209d. A shaft connection groove 235 is also shown. It will be apparent that actuated wrist mechanism 200a and / or an attachment such as a surgical tool may further comprise a cannula. The cannula may be configured to provide one or more suction channels and / or one or more irrigation channels. Embodiments are also contemplated wherein the actuated wrist mechanism 200a and / or a surgical tool (or other attachment) may be provided with one or more integrated suction and irrigation channels. The one or more integrated suction and irrigation channels may be configured to enable fluid management at an instrument tip of the surgical tool. The one or more integrated suction and irrigation channels may be configured to capture tissue and / or provide a suture port and / or provide a clear surgical field.

[0186] The arrangement illustrated in Fig. 8 offers several important advantages. By providing dedicated tendon guides for each tendon, the actuated wrist mechanism ensures that the tendons are routed in an organised and protected manner, minimising friction and wear while maximising the efficiency of force transmission. This precise routing supports highly controlled and independent actuation of the surgical tool in multiple directions, such as pitch and yaw, thereby enhancing the dexterity and responsiveness of the instrument.

[0187] The integration of a central suction and irrigation channel, or the provision of one or more cannulas, allows for effective fluid management directly at the instrument tip. This capability is particularly valuable in minimally invasive procedures, as it enables the removal of debris, blood, or other fluids from the surgical site without the need for additional instruments. The ability to capture tissue, provide a suture port, or maintain a clear surgical field further streamlines the surgical workflow and reduces the risk of complications.

[0188] Moreover, the modular design, with clearly defined pathways for both mechanical actuation and fluid management, facilitates miniaturisation and customisation of the instrument for specific clinical applications. The combination of robust mechanical control and integrated auxiliary functions in a compact form factor represents a significant improvement over conventional arrangements, supporting safer, more efficient, and more effective surgical procedures.

[0189] According to various embodiments an arthroscopic surgical instrument is disclosed which comprises the apparatus as described above. It will also be understood that a method is disclosed which comprises providing apparatus as described above and actuating the actuated wrist mechanism in order to move and / or control the surgical tool. The method may comprise a method of surgery, especially a method of performing arthroscopic surgery.

[0190] According to various embodiments, an arthroscopic surgical instrument is disclosed which comprises the apparatus as described above. This instrument is specifically designed to address the challenges of minimally invasive joint surgery by providing enhanced dexterity, precise control, and integrated auxiliary functions such as suction and irrigation. The combination of an actuated wrist mechanism, one or more tendons, and a surgical tool with complementary abutment surfaces allows the surgeon to manipulate the instrument tip with a high degree of accuracy, even within the confined and complex anatomy of a joint.

[0191] It will also be understood that a method is disclosed which comprises providing apparatus as described above and actuating the actuated wrist mechanism in order to move and / or control the surgical tool. The method may include steps such as positioning the instrument through a small portal, using the actuated wrist mechanism to orient and operate the surgical tool, and employing integrated suction and irrigation channels to maintain a clear surgical field. The actuation of the tendons, which may be controlled manually or via a robotic system, enables the surgeon to perform complex manoeuvres such as cutting, grasping, suturing, or tissue manipulation with improved precision and reduced risk of tissue damage.

[0192] The method may comprise a method of surgery, especially a method of performing arthroscopic surgery. In such procedures, the instrument can be used to diagnose and treat a variety of joint conditions, including the removal of damaged tissue, repair of ligaments or cartilage, and the placement of sutures or implants. The enhanced manoeuvrability and control provided by the actuated wrist mechanism allow the surgeon to access difficult-to-reach areas of the joint, potentially reducing the need for multiple portals or instrument exchanges. This can lead to shorter procedure times, less trauma to surrounding tissues, and improved patient outcomes. Furthermore, the integration of force feedback and fluid management features supports safer and more effective surgical interventions, making the disclosed instrument and method highly advantageous for modern arthroscopic practice.

[0193] Overall, a surgical instrument is disclosed comprising an actuated wrist mechanism comprising a shaft having a first abutment surface, wherein the shaft optionally comprises one or more grooves or channels. The surgical instrument further comprises a surgical tool having a second abutment surface, wherein the first abutment surface is abutted against the second abutment surface and wherein the surgical tool optionally further comprises one or more recesses or sockets. One or more tendons are provided and each tendon is arranged to have an end portion so that each end portion can be located, in use, within one of the one or more recesses or sockets. The surgical instrument further comprises one or more motors for actuating the one or more tendons, wherein the one or more motors are configured to transmit force to the surgical tool via the one or more tendons in order to move and / control the operation of the surgical tool in use. A force measuring device may be provided for measuring the back electromotive force (“EMF”) generated by the one or more motors, wherein the force measuring device generates an output or signal indicative of the force(s) exerted on the surgical tool and / or the force(s) experienced by the surgical tool.

[0194] It will also be understood that embodiments are contemplated which extend more generally to apparatus which comprises a mechanism configured to control the movement and / or operation of an attachment. The mechanism may comprise a shaft portion optionally comprising a collar, wherein the collar comprises a first abutment surface and wherein the shaft portion optionally further comprises one or more grooves. An attachment may be provided which comprises a second abutment surface, wherein the second abutment surface is configured to abut against the first abutment surface. One or more tendons are provided wherein optionally each tendon is arranged in one of the one or more grooves, and wherein each tendon optionally comprises an end portion. Each tendon may be actuated by one or more motors and a control system may be provided which is configured to cause the one or more motors to actuate one or more of the tendons so as to move and / or operate the attachment in a desired manner. The apparatus may comprise a component of a robot or robotic system and in particular may comprise a component of a surgical robot or surgical robotic system.

[0195] Embodiments are contemplated wherein the actuated wrist mechanism according to various embodiments is configured for use with low speed tendon-driven instruments such as a grasper, punch or scissors. According to these embodiments the surgical tool may be connected to an electrical power surface such that a voltage is applied to at least a portion of the surgical and in particular a portion of the surgical tool which comes into contact with e.g. tissue, bone, connective tissue or cartilage. The application of a voltage to a portion of the surgical tool may assist in cutting performance and / or may assist in stopping bleeding at the wound site.

[0196] Accordingly, embodiments are contemplated wherein the one or more tendons may comprise an electrically conductive core. For example, stainless steel, copper or a metallic alloy may be used to form the conductive core. The conductive core may be surrounded by an electrically insulating sheath. In addition, in order to protect a surgeon, the patient or other devices in close proximity to the surgical tool then various portions of the surgical tool and / or the one or more tendons may be electrically insulated by, for example, applying a plastic electrically insulating coating. In particular, loading bearing components may be formed from metal such as stainless steel or carbon fibre whereas non-load bearing components may be formed from an electrical insulator such as a plastic.

[0197] Fig. 9 shows further embodiments a surgical tool may be attached to the actuated wrist mechanism via tendons which are capable of supplying electrical power to at least a portion of the surgical tool. According to various embodiments the one or more tendons (which will be understood as being able to transmit force e.g. tension) may be externally coated and used for electrical connection to a surgical tool such as a pair of scissors or a clamp. The blades of the scissors or clamp may be supplied with electrical power via the tendons and this may assist in stopping bleeding at a wound site. A nonconducting collar may be provided which isolates the tip of the surgical tool from the shaft. As shown in Fig. 9 embodiments are contemplated wherein the surgical tool may comprise an upper or first electrode pad and a lower or second electrode pad wherein the pads may be supplied with electrical power via the tendons. The other surfaces of the blades, jaws and surgical tool may be provided with a non-conductive outer barrier which may serve to protect the patient and / or surgeon. The non-conductive outer barrier or surface also enables the electro-surgical tool to be operated in close proximity to other tools and reduce any risk of damage or electrocution when tools are in close proximity in a confined space. A system electrical connector may be provided and the instrument may be provided with conductive tracks for electrical transmission.

[0198] An advantage of the arrangement shown in Fig. 9 is that it enables the tendons to serve a dual function, both transmitting mechanical force and supplying electrical power to the surgical tool. This integration allows for the use of electrosurgical instruments, such as scissors or clamps, which can be energised directly via the tendons to assist in cutting tissue and achieving haemostasis by stopping bleeding at the wound site. The provision of a non-conductive collar and outer barriers enhances safety by electrically isolating the active tip from the shaft and surrounding structures, thereby reducing the risk of accidental electrical conduction, patient injury, or interference with other instruments. This design also allows the electrosurgical tool to be safely operated in close proximity to other devices within the confined space of a minimally invasive procedure, improving versatility and clinical outcomes.

[0199] Fig. 10 shows embodiments wherein the tendons may comprise braided metallic cables with an electrically insulating sheath which may be utilised to supply electrical power to an attached surgical tool. According to various embodiments the tendons may comprise twisted stainless steel cables which provide both tensile strength and enable electrical power to be transmitted via the tendon. The outer portion of the tendon may be provided with an electrically insulating sheath e.g. made from a plastic material. Other embodiments are contemplated including using a series of tendons with electrical and mechanical connections to each other.

[0200] According to various embodiments the tendons may comprise braided metallic cables with an electrically insulating sheath, enabling them to supply electrical power to an attached surgical tool. In particular, the tendons may be formed from twisted stainless steel cables, which provide excellent tensile strength for mechanical actuation while also serving as conductors for electrical power transmission. The outer portion of each tendon may be coated with an electrically insulating sheath, such as a plastic material, to prevent unintended electrical contact with other components or surrounding tissue.

[0201] Alternative embodiments are also contemplated in which the tendons may be constructed from other conductive materials, such as copper or medical-grade alloys, depending on the required balance of mechanical and electrical properties. The insulating sheath may be formed from various biocompatible polymers, such as polyether ether ketone (PEEK), silicone, or polyurethane to ensure durability and patient safety. In some configurations, a multi-layered tendon structure may be used, with an inner conductive core and an outer insulating layer, or with multiple conductors embedded within a single sheath to allow for the independent supply of power to different parts of the surgical tool.

[0202] Further alternatives include the use of a series of tendons, each with dedicated electrical and mechanical connections, allowing for redundancy or the selective energisation of specific tool components. For example, separate tendons may be used to supply power to different electrode pads, sensors, or heating elements integrated into the surgical tool, while still providing the necessary mechanical actuation.

[0203] It will be apparent that by integrating electrical power transmission into the tendon structure, the need for separate wiring or additional electrical connectors is eliminated, resulting in a more compact and streamlined instrument. The use of an insulating sheath ensures that electrical power is delivered safely and precisely to the intended part of the tool, reducing the risk of accidental burns, short circuits, or interference with other instruments. This design also enhances the versatility of the surgical tool, enabling it to perform both mechanical and electrosurgical functions within a single, minimally invasive device. Overall, these features contribute to improved surgical efficiency, safety and clinical outcomes.

[0204] Fig. 11 shows a prior art surgical instrument having a pair of jaws at the distal end of an elongate shaft. The jaws are pivotally mounted so that they can open and close relative to one another. Each jaw has an inner surface provided with serrations to enhance gripping engagement with tissue or other material. The jaws are actuated by a mechanism within the shaft, such as a sliding linkage or pull wire, which transmits motion from a proximal handle to the distal end. The arrangement allows the instrument to be inserted through a narrow access port and used in minimally invasive procedures for grasping, holding and manipulating tissue or other small objects.

[0205] This type of prior art instrument is widely used in minimally invasive surgical procedures, such as laparoscopy and arthroscopy, where access to the surgical site is limited to small incisions or portals. The design, featuring an elongate shaft and pivotally mounted jaws, enables the surgeon to reach deep or confined anatomical spaces while maintaining the ability to grasp, hold, or manipulate tissue with precision. The serrated inner surfaces of the jaws improve the instrument’s ability to securely grip slippery or delicate tissues, reducing the risk of slippage during critical manoeuvres. However, while effective for basic grasping and manipulation, such instruments are limited in their dexterity and range of motion, as the actuation mechanism typically only allows for simple opening and closing of the jaws. This restricts the surgeon’s ability to perform more complex tasks or to access certain anatomical regions without repositioning the instrument or creating additional portals, which can increase procedure time and patient trauma. The limitations of this conventional design highlight the need for more advanced instruments capable of providing enhanced articulation, force transmission, and multifunctionality within the constraints of minimally invasive surgery.

[0206] Fig. 12 shows other known surgical instruments having an elongate shaft with a pair of opposed jaws at its distal end. The jaws are pivotally mounted to open and close relative to each other, with serrated inner surfaces to improve gripping of tissue. A linkage mechanism within the shaft transmits actuation forces from a proximal handle to the distal jaws. The distal tip is shaped to provide a compact profile for insertion through a trocar or other minimally invasive surgical access port. The arrangement allows the instrument to be used in endoscopic or laparoscopic procedures for grasping and manipulating tissue.

[0207] This type of instrument is a staple in minimally invasive surgery, where the ability to introduce tools through small incisions is essential for reducing patient trauma and promoting faster recovery. The compact design of the distal tip ensures that the instrument can be easily navigated through narrow access ports, while the opposed jaws provide a reliable means of grasping, holding, or manipulating tissue and other materials within the body. The serrated inner surfaces of the jaws are particularly advantageous for securing slippery or delicate tissues, minimising the risk of slippage during critical surgical manoeuvres.

[0208] The actuation mechanism, typically a sliding linkage or pull wire, enables the surgeon to control the opening and closing of the jaws from the proximal handle, allowing for precise and responsive operation. However, despite these benefits, such instruments are generally limited to a single degree of freedom at the distal end, restricting the range of movements that can be performed. This limitation can make it challenging to access certain anatomical regions or to perform more complex tasks without repositioning the instrument or using multiple access ports. As a result, there is a need for improved instruments that offer greater dexterity, enhanced articulation, and multifunctionality while maintaining the minimally invasive profile required for advanced surgical procedures.

[0209] Fig. 13 shows a selection of known surgical instruments, each having a pair of jaws at the distal end of an elongate shaft. The instruments are provided in a variety of jaw shapes and configurations, each tailored to suit different surgical applications and tissue types. Examples illustrated include jaws shaped as a scissor punch for cutting, jaws with opposed serrated surfaces referred to as Ratman and Crocodile for enhanced gripping, flat-faced jaws referred to as Black Mamba for broad tissue manipulation, angled jaws referred to as Anaconda for access to difficult anatomical regions, and curved jaws referred to as Python for navigating around structures or providing a sweeping action. Each instrument is configured so that actuation of a proximal handle causes the distal jaws to open and close, enabling the surgeon to grip, cut, or manipulate tissue as required during minimally invasive procedures.

[0210] This diversity in jaw design reflects the need for specialised tools to address the wide range of tasks encountered in surgery, from delicate dissection to robust tissue removal. However, while these instruments offer some degree of customisation, they are generally limited to a single function and require the surgeon to exchange instruments frequently during a procedure, which can increase operative time and complexity. Furthermore, the actuation mechanisms are typically limited to simple opening and closing motions, restricting the instrument’s dexterity and adaptability within the surgical site.

[0211] Fig. 14 shows a robotic surgical tool assembly that represents a more advanced approach to minimally invasive surgery. The tool includes an elongate shaft terminating in an articulated end effector, which is formed with opposed jaws mounted to pivot relative to each other. The end effector is connected to a compact actuation mechanism housed at the distal end of the shaft. This actuation mechanism comprises multiple gear sets and linkages, which are arranged to transmit controlled movement from a robotic drive system along the shaft to the jaws.

[0212] The figures illustrate different views of the tool, including a perspective view of the actuation mechanism, an enlarged detail of the gear assembly, and side views showing the elongate shaft with the end effector at its distal end. This arrangement allows for precise robotic control of the jaw movements, enabling the surgeon to perform grasping, cutting, or manipulating tasks with a high degree of accuracy and repeatability during minimally invasive surgical procedures. The integration of robotic actuation overcomes many of the limitations of manual instruments, providing enhanced dexterity, stability, and the potential for complex multi-axis movements that are not possible with traditional designs. This advancement marks a significant step forward in the evolution of surgical instrumentation, paving the way for more sophisticated and less invasive surgical techniques.

[0213] Fig. 15 shows a robotic surgical tool having an elongate shaft with a distal gripper unit and a proximal drive interface. The gripper unit comprises a pair of jaws mounted to pivot relative to each other for grasping tissue. Motion of the jaws and of a wrist joint at the distal end is transmitted by tension cables running through the shaft. The proximal end of the shaft is connected to a drive housing that provides separate inputs for actuating the gripper and for two degrees of wrist motion. The figure illustrates perspective and schematic views of the assembly, including the arrangement of the tension cables and their connection between the proximal drive unit and the distal gripper. This arrangement enables controlled articulation of the gripper and wrist for precision handling in minimally invasive robotic surgery.

[0214] This configuration offers several advantages over conventional manual instruments. By employing tension cables to transmit motion from the proximal drive unit to the distal gripper and wrist, the tool achieves highly responsive and accurate actuation, allowing the surgeon or robotic system to perform delicate and complex manoeuvres with ease. The separation of control inputs for the gripper and the wrist joint provides independent and simultaneous control of both the opening and closing of the jaws and the articulation of the wrist, greatly enhancing dexterity and access within confined anatomical spaces.

[0215] Furthermore, the use of a proximal drive housing allows for the integration of advanced control systems, such as robotic actuators or haptic feedback devices, which can further improve the precision and safety of surgical procedures. The cable-driven design also supports miniaturisation, making the instrument suitable for use through small surgical ports or trocars, and reducing patient trauma. Fig. 16 shows a robotic surgical tool incorporating an articulated wrist joint and a distal gripper according to various embodiments The distal gripper unit comprises a pair of jaws mounted to pivot relative to each other, with motion transmitted by tension cables extending along the shaft. The proximal drive housing provides separate actuation inputs for the gripper and for two degrees of wrist articulation. The upper perspective view illustrates the compact wrist mechanism with a ball joint configuration, which allows for multi-axis articulation and enables the distal end of the tool to move with a high degree of freedom.

[0216] The schematic diagrams further illustrate the routing of tension cables for actuating both the gripper and the wrist, demonstrating how precise and coordinated movements can be achieved. Comparative views of conventional surgical forceps and pulley arrangements are also provided, highlighting the improvements in cable transmission and control offered by the present design.

[0217] This arrangement provides several advantages. The use of a ball joint configuration at the wrist enables the tool to articulate in multiple directions, such as pitch, yaw, and roll, thereby greatly enhancing the dexterity and reach of the instrument within confined anatomical spaces. The separation of actuation inputs for the gripper and the wrist allows for independent and simultaneous control, supporting complex surgical manoeuvres that would be difficult or impossible with traditional instruments. The tension cable system ensures smooth and responsive transmission of force, reducing backlash and improving the surgeon’s ability to perform delicate tasks with precision

[0218] Fig. 17 shows a robotic surgical tool having an elongate shaft with a distal end effector in the form of opposed jaws according to an embodiment The jaws are pivotally mounted to open and close relative to each other for gripping tissue. The distal end of the shaft further includes a wrist joint allowing angular articulation of the jaws relative to the shaft. The proximal end of the shaft is configured for connection to a drive system that transmits motion to both the wrist joint and the jaws. The arrangement allows the end effector to be introduced through a minimally invasive surgical access port and manipulated with multiple degrees of freedom for precise tissue handling.

[0219] This configuration provides several important advantages. The inclusion of a wrist joint at the distal end enables the jaws to be articulated independently of the main shaft, allowing the surgeon to adjust the orientation and angle of the end effector within the surgical site. This is particularly beneficial in minimally invasive procedures, where access is limited and the ability to reach around anatomical structures is essential. The multiple degrees of freedom afforded by the combination of the wrist joint and the pivoting jaws allow for complex manoeuvres, such as grasping, rotating, and repositioning tissue, all through a single access port. Fig. 18 shows a robotic surgical tool interface assembly. The first view illustrates a connector layout having an oval profile with an overall size of 50 mm by 50 mm and a central section 30 mm wide. The connector accommodates four circular ports, including a 14 mm diameter 10-pin Redel connector and three 13 mm diameter ports designated M7, M8 and M9. This arrangement allows for the efficient connection of electrical and mechanical interfaces required for the operation and control of the surgical tool, supporting rapid and secure attachment or detachment of the instrument from the robotic system.

[0220] The second view illustrates a mechanical housing with an internal arrangement of drive pulleys and shafts configured to transmit motion to an elongate surgical tool shaft mounted at the front of the housing. The shaft terminates in a distal end effector and is actuated by the internal pulley and drive arrangement. The use of multiple pulleys and shafts enables the precise transfer of motion from external drive motors to the various degrees of freedom at the distal end of the tool, such as jaw actuation and wrist articulation.

[0221] This configuration provides a compact and integrated interface between the external drive motors and the surgical instrument, enabling controlled and coordinated operation of the tool during robotic procedures. The modular design of the interface assembly facilitates quick instrument changes, reduces setup time, and enhances the overall flexibility of the robotic surgical system. Additionally, the compact housing minimises the footprint of the drive mechanism, allowing for a more ergonomic and space-efficient setup in the operating theatre. This design supports improved workflow, reliability, and ease of use for both the surgical team and the robotic system.

[0222] Fig. 19 shows a detailed view of a bearing and joint assembly for a robotic surgical tool according to various embodiments. The upper images illustrate cylindrical bearing housings with dimensional specifications, including tolerances for clearances and wall thicknesses. The drawings show a ball joint structure with surrounding cylindrical supports, together with sections indicating the interaction between fixed and movable elements. The lower image illustrates a three-dimensional CAD rendering of a drive housing containing multiple pulley wheels and a central mounting block. The pulleys are arranged to transmit motion through tension cables extending into the elongate shaft of the surgical tool. The combination of the bearing arrangement and pulley drive provides smooth actuation of the distal end effector and controlled articulation of the tool during minimally invasive robotic surgery.

[0223] In the first view on the left, the overall outer diameter is 3.5 mm with an internal diameter of 2.9 mm, leaving a wall thickness of 0.3 mm on one side and 0.4 mm on the other. The cylindrical sections are each 1.0 mm high, providing a combined section height of 2.0 mm. Elliptical outlines within the cylinder indicate the clearance path for a spherical component.

[0224] In the middle view, a spherical element of 3.0 mm diameter is positioned between the two cylindrical housings. A clearance of 0.15 mm is provided above the sphere and 0.2 mm below, while the side clearance is also 0.2 mm to permit rotational movement. A dimension of 2.2 mm shows the chordal width of the spherical section captured within the housing.

[0225] In the right view, two cylindrical housings are shown with a separation of 0.2 mm between them, defining the free play that allows articulation of the ball while preventing excessive looseness. The arrangement of dimensions illustrates how the ball is retained securely yet permitted to rotate within controlled tolerances.

[0226] This detailed engineering design offers several advantages. The precise tolerances and clearances ensure that the ball joint can articulate smoothly in multiple directions while maintaining stability and minimising unwanted play or backlash. This is critical for achieving accurate and repeatable movements of the distal end effector, which is essential in delicate minimally invasive surgical procedures. The compact dimensions of the bearing and joint assembly also support miniaturisation of the overall instrument, allowing it to be used through small surgical ports. Furthermore, the integration of the bearing assembly with the pulley-driven actuation system enables efficient and reliable transmission of motion from the proximal drive unit to the distal tool, enhancing both dexterity and control for the surgeon.

[0227] Fig. 20 shows a view of a drive module for a robotic surgical tool according to an embodiment. The module contains multiple pulley wheels and cable routings arranged to transmit actuation forces to an elongate surgical shaft. The cables enter the module from the proximal side and are guided around pulleys arranged in pairs to provide controlled tension and directional changes. The housing secures the pulley system and includes mounting points for connection to a robotic drive unit. This configuration enables precise transfer of motion from external actuators to the distal end effector of the tool while maintaining compactness within the drive housing.

[0228] This arrangement offers several advantages. By using multiple pulleys and carefully routed cables, the drive module can efficiently transmit complex actuation patterns to the distal end of the surgical tool, supporting multi-degree-of-freedom movements such as pitch, yaw, and roll. The paired pulley arrangement ensures that cable tension is maintained evenly, reducing slack and minimising backlash, which is essential for achieving accurate and repeatable tool movements during delicate surgical procedures. The compact design of the drive housing allows the module to be integrated into space-constrained environments, such as the proximal end of a robotic arm or surgical console, without adding unnecessary bulk.

[0229] Furthermore, the modular nature of the drive unit facilitates maintenance and customisation, as individual pulleys or cable paths can be accessed and serviced as needed. The secure mounting points ensure stable attachment to the robotic system, enhancing overall reliability and safety.

[0230] Fig. 21 shows a robotic surgical wrist mechanism configured to provide multiple degrees of articulation according to an embodiment. The upper view illustrates the proximal drive layout with separate motion channels for right and left motion through an angle of 35 degrees, up and down motion through an angle of 35 degrees, and jaw actuation providing up and down motion through an angle of 90 degrees. This arrangement allows for independent and precise control of each axis of movement, enabling the surgeon or robotic system to position and orient the end effector with a high degree of accuracy.

[0231] The middle and lower views illustrate a distal wrist joint according to an embodiment which incorporates a spherical element housed within a support collar. Cable guides extend over the spherical element to transmit motion and provide controlled articulation. The spherical element acts as a central pivot, allowing the distal end effector to move smoothly in multiple directions, including pitch, yaw, and roll, while maintaining stability and structural integrity.

[0232] This configuration offers several advantages. The use of a spherical wrist joint enables true multi-axis articulation, which is essential for accessing difficult-to-reach anatomical sites and performing complex surgical manoeuvres within confined spaces. The cable-driven actuation system ensures that movements are both responsive and finely controlled, reducing the risk of unintended motion or mechanical play. Independent control of the wrist and jaw actuation allows the surgeon to perform delicate tasks, such as suturing or tissue dissection, with enhanced dexterity and precision.

[0233] Furthermore, the compact design of the wrist mechanism supports miniaturisation, making it suitable for use in minimally invasive procedures where instrument size is a critical factor. The integration of multiple degrees of freedom within a single, robust assembly represents a significant advancement over traditional rigid or single-axis wrist designs, ultimately contributing to improved surgical outcomes and greater versatility in robotic-assisted surgery.

[0234] Fig. 22 shows embodiments of robotic surgical tools incorporating the articulated wrist mechanism described above according to various embodiments. The upper view illustrates a tool with a curved electrosurgical tip mounted at the distal end of the shaft, allowing precise positioning and articulation for cutting or cauterising tissue. The ability to articulate the electrosurgical tip enables the surgeon to access and treat tissue at challenging angles and in confined anatomical spaces, improving the effectiveness and safety of electrosurgical procedures.

[0235] The lower view illustrates a tool with a pair of opposed jaws mounted at the distal end for grasping and manipulating tissue. The jaws can be opened, closed, and articulated in multiple directions, supporting a wide range of surgical tasks such as dissection, tissue manipulation, and suturing. Each tool includes a spherical wrist joint and a cable-driven actuation system, enabling multi-axis articulation of the distal end effector relative to the elongate shaft. This configuration allows for independent and coordinated movements in pitch, yaw, and roll, providing the surgeon with a high degree of dexterity and control.

[0236] A key advantage of this arrangement is that it allows interchangeable surgical instruments to be mounted on a common wrist structure. This modularity means that a single robotic arm can be quickly adapted for different surgical tasks by swapping out the end effector, whether it be a grasper, scissors, or electrosurgical tip. This not only streamlines the surgical workflow and reduces instrument exchanges, but also minimises the number of access ports required, thereby reducing patient trauma and operative time.

[0237] Fig. 23 shows a robotic surgical tool incorporating an articulated wrist joint and a distal grasper. The upper view illustrates the tool with jaws in an open position, the middle view shows the jaws in a closed position, and the lower view provides an enlarged detail of the distal end. The jaws are mounted to pivot relative to each other and include serrated inner surfaces for improved gripping of tissue. The wrist mechanism enables articulation of the jaws relative to the elongate shaft, allowing enhanced dexterity.

[0238] This arrangement offers several advantages. The ability to articulate the jaws independently of the main shaft means the surgeon can precisely position and orient the grasper tip within the surgical site, even in anatomically complex or confined spaces. The serrated inner surfaces of the jaws ensure secure engagement with tissue, reducing the risk of slippage and enabling reliable grasping, manipulation, or dissection.

[0239] The combination of wrist articulation and controlled jaw movement allows for complex manoeuvres, such as rotating, angling, or repositioning tissue, all through a single minimally invasive access port. This reduces the need for multiple instrument exchanges or additional incisions, thereby minimising patient trauma and operative time. The robotic actuation system provides smooth, responsive and repeatable control, supporting both delicate and forceful actions as required by the surgical task. Overall, the design shown in Fig. 23 enhances the surgeon’s ability to perform intricate procedures with greater confidence, precision, and efficiency, contributing to improved clinical outcomes in minimally invasive surgery.

[0240] Fig. 24 shows an experimental assembly of a cable-driven surgical tool. The upper view illustrates a proximal actuation housing in which multiple control cables are secured and routed into an elongate shaft. The shaft transmits the cable motions to a distal end effector. The lower view shows the distal end of the shaft with a miniature grasper or jaw mechanism, the cables being used to actuate opening and closing movements. The photographs demonstrate a working prototype of the cable-driven actuation system for minimally invasive surgical applications, where motion applied at the proximal housing is transmitted through the shaft to operate the distal tool.

[0241] The use of control cables allows for precise and responsive actuation of the distal end effector, enabling the surgeon to perform delicate tasks such as grasping, holding, or manipulating tissue with fine control. The cable-driven design also supports miniaturisation, making it possible to create instruments with a slender profile suitable for insertion through small surgical ports or trocars.

[0242] Furthermore, the prototype demonstrates the feasibility of integrating multiple degrees of freedom into a compact instrument, as the cables can be routed and tensioned to support complex movements such as opening, closing, and articulating the jaws. The modular nature of the assembly allows for easy adjustment, maintenance, and replacement of components, which is advantageous for both clinical use and ongoing development.

[0243] Fig. 25 shows a prototype of a cable-driven robotic surgical tool alongside a corresponding CAD model. The upper image illustrates a physical assembly with an elongate shaft terminating in a distal grasper. The shaft is connected proximally to a circular drive plate housing multiple control cables, which are tensioned to operate the distal jaws. The lower image illustrates a CAD rendering of the same arrangement, showing the internal pulley and drive system located within the proximal housing and the cable routing through the shaft to the distal end effector. This configuration demonstrates the integration of the cable-driven actuation system into a compact surgical tool suitable for minimally invasive robotic applications.

[0244] It will be apparent that the use of a circular drive plate and multiple control cables allows for precise and coordinated actuation of the distal jaws, enabling complex movements such as grasping, rotating, and manipulating tissue with a high degree of accuracy. The integration of the pulley and drive system within the proximal housing ensures that the actuation forces are transmitted efficiently along the length of the shaft, minimising friction and mechanical losses. The compact and modular design of the prototype makes it well suited for use in minimally invasive procedures, where instrument size and dexterity are critical. The cable-driven approach supports miniaturisation without sacrificing strength or control, and the modular construction allows for easy maintenance, repair or customisation for specific surgical tasks.

[0245] Fig. 26 shows detailed CAD views of components for a robotic surgical tool. The upper view illustrates a proximal drive housing containing multiple pulleys and mounting features configured to guide and tension control cables. The pulleys are supported on axles fixed between two circular side plates, with slots and fasteners allowing precise alignment and adjustment. This design ensures that the control cables are routed accurately and maintained under optimal tension, which is essential for reliable and repeatable actuation of the distal end effector.

[0246] The lower view illustrates a distal gripper component having opposed jaws with serrated inner surfaces. The jaws are pivotally mounted within a body section that includes openings and channels for routing actuation cables. The cable routing is carefully designed to minimise friction and wear, while also allowing for smooth and responsive movement of the jaws. The serrated inner surfaces of the jaws enhance the instrument’s ability to securely grip tissue or other materials during surgical procedures.

[0247] This arrangement enables controlled opening and closing of the jaws through cable actuation transmitted from the proximal drive housing, providing a functional link between the proximal drive system and the distal surgical end effector. The modularity of the design allows for easy assembly, maintenance, and potential customisation of the tool for different surgical applications.

[0248] Fig. 27 shows a distal tool assembly with integrated suction and electrical connection features. The upper view illustrates a CAD rendering of an instrument tip housing, which incorporates an actuation joint for jaw movement. The lower schematic views illustrate the internal arrangement of the assembly. An end cap provides entry for a suction tube, sealed with silicone, and is supported by internal struts to maintain structural integrity and prevent collapse of the suction pathway. Control cables are secured by an interference lock for tensioning, ensuring that the cables remain taut and responsive during operation, with proximal connection to a motor drive system for precise actuation.

[0249] Electrical connectors are integrated within the housing, enabling the delivery of power to, or the collection of signals from, elements at the tip (such as sensors, heating elements, or electrosurgical electrodes). This integration allows the instrument to perform advanced functions such as tissue sensing, cauterisation or real-time feedback during surgery. The arrangement is configured to allow articulation of the instrument tip through ±90 degrees, with articulation limits set by motor control or software to prevent overextension and ensure safe operation. This high degree of articulation enables the surgeon to access and treat tissue in anatomically challenging or confined spaces, greatly enhancing the versatility of the tool.

[0250] This configuration offers several advantages. By combining mechanical actuation, suction functionality, and electrical connectivity within a single, compact surgical end effector assembly, the instrument reduces the need for multiple separate devices in the surgical field. This not only streamlines the workflow and minimises instrument exchanges, but also improves ergonomics and reduces clutter. The integrated design supports advanced minimally invasive procedures, enabling the surgeon to perform complex tasks with greater precision, efficiency and safety.

[0251] Fig. 28 shows a further view of the distal tool assembly illustrating the housing structure and cable routing. The figure highlights the integration of the suction line, electrical connection, and cable actuation within the compact housing.

[0252] This view provides additional detail on how the various functional elements are organised within the limited space at the distal end of the instrument. The housing is designed to accommodate the routing of control cables alongside the suction line and electrical wiring, ensuring that each pathway is optimally positioned to minimise friction, interference, and the risk of entanglement. The careful arrangement of these elements allows for smooth and reliable actuation of the jaws or other end effector components, while simultaneously enabling efficient suction and the delivery of electrical power or signals to the tip.

[0253] The compact integration of these features within a single housing is particularly advantageous in minimally invasive surgery, where instrument diameter must be kept as small as possible to reduce tissue trauma and allow access through narrow surgical ports. By combining mechanical, fluidic, and electrical functionalities in a unified structure, the design supports advanced surgical procedures that require precise manipulation, effective fluid management, and the use of powered or sensor-equipped end effectors. This approach also simplifies instrument assembly and maintenance, as all critical systems are contained within a single, modular unit.

[0254] Fig. 29 shows detailed aspects of a surgical handpiece and distal actuation mechanism. The upper view illustrates the proximal end of the handpiece with an interface plate of approximately 62.98 mm by 73.20 mm. Multiple ports are provided for electrical and mechanical connections, including a suction line and cable pathways for instrument actuation. This arrangement allows for the integration of different drive and control functions within a single, compact interface, streamlining the connection to external systems such as robotic controllers, power supplies, and fluid management units. The compact design of the interface plate helps to minimise the overall footprint of the handpiece, making it easier to handle and manipulate during surgery, and facilitating rapid instrument setup or exchange.

[0255] The lower view illustrates a cutaway of the distal jaw mechanism. The figure shows the jaws pivotally mounted and actuated by linkages connected through spherical and pin joints, enabling smooth and precise movement. Actuation tendons having a spherical element used to transmit motion from the proximal drive system to the jaws. This design ensures that the forces generated by the surgeon or robotic system are efficiently and reliably transferred to the end effector, allowing for controlled opening and closing of the jaws.

[0256] The arrangement provides several advantages. The use of spherical and pin joints in the actuation mechanism allows for multi-directional articulation and reduces mechanical play, resulting in more accurate and repeatable jaw movements. The compact packaging of the jaw mechanism at the distal tip of the instrument is particularly well suited for minimally invasive surgical procedures, where space is limited and precise control is essential. Additionally, the integration of suction and cable pathways within the handpiece supports advanced surgical functions such as fluid management and multi- degree-of-freedom actuation, further enhancing the versatility and clinical utility of the instrument.

[0257] Fig. 30 shows detailed views of a distal surgical tool jaw assembly according to an embodiment. The upper view illustrates the internal actuation elements. The jaws are pivotally connected by a spherical joint and actuated by cable linkages routed along the shaft. This arrangement demonstrates how motion is transmitted through the spherical element to achieve controlled pivoting of the jaws, allowing for smooth and precise opening and closing movements. The use of a spherical joint provides multi-directional articulation, which is particularly advantageous for accessing and manipulating tissue in anatomically complex or confined spaces.

[0258] The lower view illustrates the jaw housing in an isolated state. The body includes pivot holes and openings for receiving the actuation cables. The cables are routed through the side apertures and secured within the housing to provide reliable and consistent movement of the jaws. This design ensures that the actuation forces are efficiently transferred from the proximal drive system to the distal end effector, minimising friction and mechanical losses.

[0259] The compact integration of a robust pivot mechanism with cable-driven actuation enables precise gripping and manipulation of tissue in minimally invasive surgical applications. The modular nature of the assembly allows for straightforward maintenance, replacement or customisation of the jaws for different surgical tasks. Fig. 31 shows detailed views of a distal jaw actuation mechanism for a robotic surgical tool. The upper view illustrates the proximal section of the jaw housing, highlighting the pivot elements and cable connections that lead into the jaw assembly. Spherical elements are used as joints for transmitting motion from the cables to the moving parts, enabling smooth and multi-directional articulation of the jaws.

[0260] The middle view provides a cutaway perspective, revealing the internal linkage between the drive cables and the jaws. The housing is shown with the jaws visible inside, clearly demonstrating how the cable forces are routed around the spherical joints to actuate the jaws. This arrangement ensures that the actuation forces are efficiently transferred, allowing for responsive and controlled movement of the jaws with minimal mechanical play or friction.

[0261] The lower view is a sectional illustration showing the jaws in an open position. The drive cables extend distally, with ball-joint terminations engaging the jaws to transmit pulling forces. This configuration allows for precise control of jaw opening and closing, supporting both delicate and forceful actions as required by the surgical task. The compact geometry of the mechanism is particularly advantageous for minimally invasive surgical use, as it enables the instrument to be introduced through small access ports while maintaining a high degree of dexterity and control at the distal tip.

[0262] Fig. 32 shows sectional and assembled views of a distal end effector mechanism for a robotic surgical tool according to various embodiments. The upper view illustrates a cross section with cable routing leading into the jaw assembly. Actuation cables terminate in spherical joints that engage with the jaw elements, transmitting opening and closing forces through compact linkages. This arrangement allows for efficient and direct transfer of actuation forces, supporting precise and responsive movement of the jaws.

[0263] The middle and lower views illustrate longitudinal sections of the jaw housing in different positions. The housing includes cutouts and internal channels specifically designed to accommodate the spherical joints and linkages, ensuring smooth and unobstructed transmission of cable motion to the jaws. The internal design minimises friction and mechanical losses, contributing to the reliability and repeatability of jaw actuation.

[0264] The sectional and assembled views also highlight the functional organisation of the end effector, with distinct regions for the jaw mechanism, the main housing, and the proximal cable interface. This clear separation of functional areas supports modularity and ease of assembly or maintenance. The compact integration of the spherical joint and linkage system within the jaw housing enables reliable cable-driven actuation of the jaws, even within the tight spatial constraints required for minimally invasive surgical instruments.

[0265] Fig. 33 shows perspective views of a distal jaw assembly for a robotic surgical instrument according to an embodiment. The upper view illustrates the jaws in an open position, with the proximal actuation cables connected to spherical joints that transmit motion to the jaw pivots. This arrangement allows for smooth and controlled articulation of the jaws, enabling the surgeon or robotic system to achieve a wide range of jaw positions with high precision. The linkage and housing design ensures that the actuation forces are efficiently transferred from the proximal end of the instrument to the distal jaws, supporting both delicate and robust tissue manipulation.

[0266] The lower view illustrates the same assembly with the jaws in a closed position. The housing is designed to enclose the cable routing and joint mechanism, protecting the internal components from contamination and mechanical damage during use. The configuration of the housing, with clear separation between the distal end and the proximal shaft connection, facilitates straightforward assembly, maintenance, and potential replacement of the jaw module.

[0267] The cable-driven system enables precise and repeatable opening and closing of the jaws, making it particularly suitable for gripping, holding, or manipulating tissue in minimally invasive surgical procedures. The compact form factor of the assembly allows it to be introduced through small surgical ports, while the robust mechanical design ensures reliable performance even in demanding clinical environments. The integration of spherical joints and optimised cable routing further enhances the dexterity and responsiveness of the instrument, supporting complex surgical manoeuvres with minimal instrument bulk.

[0268] Fig. 34 shows a physical prototype of a cable-driven surgical tool according to an embodiment. The upper view illustrates the complete assembly, with a cylindrical proximal housing designed to be comfortably held in the hand and an elongate shaft extending distally from the housing. At the distal tip, a miniature grasper is mounted, which is configured for opening and closing via cable actuation routed internally through the shaft. This arrangement allows the user to control the movement of the grasper jaws from the proximal end, enabling precise manipulation at the surgical site.

[0269] The lower view provides an enlarged detail of the distal end effector. The grasper jaws are pivotally mounted and connected to cable linkages that extend proximally within the shaft. In this prototype, the cables are secured externally to the jaw pivots, clearly demonstrating how pulling forces applied at the proximal housing are transmitted along the shaft to operate the jaws. This direct mechanical linkage ensures responsive and reliable actuation, which is essential for delicate tissue handling in minimally invasive procedures. The prototype demonstrates of the translation of motion from a proximal actuation housing into controlled movement of a distal grasper. The compact and ergonomic design of the prototype also highlights its suitability for minimally invasive surgical applications, where instrument size, precision and ease of use are important factors.

[0270] Fig. 35 shows images of the distal end of a prototype cable-driven grasper. The upper view illustrates the grasper in a partially open position, with the jaws pivotally mounted at the distal tip of the elongate shaft. Cable terminations are visible around the pivot joint, secured in such a way as to allow efficient transmission of pulling forces for opening and closing the jaws. This arrangement demonstrates how the actuation system within the shaft is mechanically linked to the movement of the jaws, ensuring responsive and controlled operation.

[0271] The lower view provides a closer image of the jaws in an open position. The serrated inner surfaces of the jaws are clearly visible, specifically configured to enhance gripping of tissue during surgical procedures. The pivot pin and external cable attachments can also be seen, further illustrating the robust and direct connection between the actuation cables and the jaw mechanism. This design ensures that the forces generated at the proximal end of the instrument are reliably transferred to the distal jaws, supporting precise and repeatable grasping actions.

[0272] Fig. 36 shows further views of the distal grasper of a cable-driven surgical tool according to an embodiment. The upper view illustrates the jaws in a nearly closed position, with the pivot joint and cable attachments visible at the distal tip of the shaft. The elongate shaft is designed to support the routing of actuation cables, which extend internally along its length and terminate at the jaw pivots. This arrangement ensures that the actuation forces generated at the proximal end are efficiently transmitted to the distal jaws, enabling precise control over their movement.

[0273] The lower view illustrates the jaws in an open position, revealing the serrated inner surfaces that are specifically designed for gripping tissue securely during surgical procedures. The pivot mechanism and cable connections are visible with the jaws spread apart to demonstrate the full operational range of the grasper.

[0274] Fig. 37 shows a physical prototype of a cable-actuated joint assembly. The structure is built from two parallel aluminium plates that are held apart by bolts and spacers, forming a rigid and stable framework. Several stainless-steel cables are routed through pulleys and guide holes and are attached at anchor points on the internal mechanism. These cables enable controlled articulation by allowing the user to pull in different directions, thereby moving the joint or end-effector as required. Fig. 38 shows a closer view of the same cable-actuated joint prototype as in Fig. 37, with emphasis on the routing and anchoring of the control cables. Multiple steel cables are tensioned through the frame, looping around small pulleys and terminating at fixed anchors on the plates.

[0275] Fig. 39 shows a sectional view of a distal scissor-type end effector for a robotic surgical tool. The internal configuration of the jaws is shown together with the actuation linkages when the jaw is in a state of closure. Each jaw is pivotally connected within the housing and actuated by tension cables routed along the shaft, with spherical joints transferring motion to the blades.

[0276] The lower images highlight several design refinements of the end effector. These include a more pointed but slightly rounded tip profile, which facilitates precise access to tissue while minimising the risk of accidental injury. The length between the wrist joint and the blade is kept compact, improving manoeuvrability and allowing the surgeon to operate in confined anatomical spaces. The blades themselves have an increased curvature, forming a pronounced C-shape that enhances the ability to capture and cut tissue efficiently.

[0277] According to various embodiments the cable diameter clearance may be approximately 0.483 mm, which ensures that the actuation cables can move freely without excessive friction or risk of binding. Embodiments are contemplated wherein the size of the suction channel provided may be increased to increase effective fluid management during surgical procedures. A central section plane is illustrated with the scissors open, showing the internal configuration of the cutting blades and the routing of the actuation cables.

[0278] It will be apparent how the end effector successfully integrates mechanical cutting, cable actuation and suction functionality within a compact, cable-driven wristed surgical tool. The combination of these features supports precise, controlled cutting and efficient fluid management, making the design particularly well suited for advanced minimally invasive and robotic-assisted surgical procedures. The refinements shown in Fig. 39 contribute to improved surgical performance, ease of use, and patient safety.

[0279] Fig. 40 shows design refinements for a distal scissor-type end effector according to various embodiments. According to an embodiment the blades are shaped to maintain a double-C hook profile, with a sloped lower jaw to guide tissue into the cutting region. The tips are pointed but not sharp, configured for dissection and tissue spreading while maintaining a small cross-sectional area of approximately 1-1.5 mm for precision access. A compact single-action joint mechanism is illustrated, with blade lengths extended to about 10 mm and a cutting blade width of 0.1 -0.4 mm, consistent with common surgical practice. It will be apparent that proper jaw alignment is desired when closed to avoid mis-tracking at the pointed tip.

[0280] The middle diagram provides a sectional view showing centrally aligned cutting with minimal clearance, the risk of device failure if jaws are loose or misaligned, and the integration of suction venting channels aligned with the long axis of the tool. The section also shows a mobile tip with two degrees of freedom, capable of approximately ±35° articulation. According to an embodiment the maximum overall diameter may be 3.5 mm ensuring compatibility with minimally invasive surgical ports.

[0281] The lower diagram illustrates an end effector assembly according to an embodiment including the actuation linkages and jaw profile.

[0282] Fig. 41 shows multiple views of a distal end effector illustrating the blade arrangement and housing design according to an embodiment. The top view presents a cross-section through the cutting jaws, showing the opposed blade elements interlocking along a central cutting line and forming a scissor-type profile within a circular housing. The middle set of views display side and plan perspectives of the instrument with the housing cut away to expose the internal arrangement. These views illustrate the alignment of the two opposed blades, each pivotally supported and configured to close centrally along a defined cutting path. The plan view highlights the slot through which actuation linkages engage the jaws, demonstrating how the mechanical input is transferred to the cutting elements.

[0283] The lower perspective view provides a three-dimensional rendering of the jaw mechanism within its supporting structure. The articulation of the blades, their tapered outer surfaces, and the alignment within the cylindrical housing are illustrated, showing how the design supports both strength and precision.

[0284] The geometry of the end effector demonstrates how the blades are shaped to accept tissue into the cutting path, ensuring centralised closure and effective cutting action. This arrangement supports reliable and repeatable performance, which is particularly important for delicate or precise surgical tasks in minimally invasive procedures.

[0285] Fig. 42 shows views of an electrosurgical instrument tip incorporating jaw actuation and electrical conduction features according to an embodiment. The top view illustrates the opposed jaws in a closed position, highlighting the precise alignment of the jaw members within the distal housing to ensure effective tissue engagement and energy delivery. The central perspective view shows the jaw assembly and housing, revealing the internal actuation linkages and pivot mechanisms. The tension cables extend proximally, demonstrating how movement is transferred from the proximal drive system to the jaws, enabling controlled opening and closing. The internal arrangement ensures that both mechanical and electrical functions are integrated within a compact structure.

[0286] The lower section illustrates schematic representations of the electrosurgical conduction paths. The drawings indicate the use of externally coated tension cables that serve a dual role in both mechanical actuation and electrical conduction. The jaws are depicted with surface coatings acting as non-conductive barriers, except at defined electrode pads. These electrode pads, positioned on the upper and lower jaws, are connected electrically to allow for tissue sealing or coagulation during surgical procedures. A system electrical connector is shown at the proximal end, interfacing with conductive tracks that extend along the shaft to deliver energy to the distal tip.

[0287] This configuration demonstrates the integration of mechanical actuation with controlled electrical functionality, providing both gripping and electrosurgical effects in a compact end effector. The design allows the surgeon to perform precise tissue manipulation and energy delivery with a single instrument, reducing the need for instrument exchanges and improving procedural efficiency. The combination of safe electrical isolation, reliable actuation and multifunctionality makes this arrangement particularly advantageous for advanced minimally invasive and robotic-assisted surgical procedures.

[0288] Fig. 43 shows perspective and side views of the proximal housing of the surgical instrument where the shaft connects to the drive and control module. The housing incorporates multiple distinct components, each representing different functional assemblies that contribute to the overall operation and integration of the instrument. The distal end of the module is connected to the elongate shaft, which extends forward to the surgical site. Surrounding the main body, an external casing encloses and protects the internal mechanisms, with strategically placed openings and cut-outs for venting or service access. A segment is positioned dorsally providing reinforcement and / or serving as an interface for securing the unit to the main robotic or hand-held platform.

[0289] External metallic conduits and connectors are shown mounted along the outer housing. These conduits are shaped to provide efficient routing for cabling, which may include actuation cables and electrical conductors that extend distally through the shaft to the end effector. A region at the rear of the housing includes a further attachment or connector interface, supporting modularity and ease of connection to external systems. The views demonstrate how the proximal housing integrates electrical, mechanical, and control connections in a compact and organised arrangement. This modular design enables the elongate surgical shaft to be coupled to the main drive system while maintaining convenient access for power, signal and cable management. Such an arrangement supports rapid instrument setup, maintenance and exchange and contributes to the reliability and versatility of the surgical system in both robotic and manual applications.

[0290] Fig. 44 illustrates detailed views of the proximal housing assembly of the surgical instrument according to an embodiment. The top perspective view shows the outer casing and the internal components. Inside, multiple mechanical elements and alignment structures are located with the shaft extending forward. A protective cover is located dorsally, while a curved metallic conduit extends externally to provide routing for cabling or tubing.

[0291] The middle view shows how the proximal motor unit couples with an intermediate connector and the distal housing section. This illustrates the modular attachment system for connecting and disconnecting the drive unit from the instrument housing.

[0292] The lower perspective highlights the internal face of the housing, showing multiple circular interfaces and alignment points where the motor and transmission components connect. The conduit and housing geometry are designed to provide access for electrical and mechanical connections while maintaining a compact form factor.

[0293] Fig. 45 illustrates the integration of the drive motor assembly within the proximal housing structure of the surgical instrument, with multiple sectional views provided to show different internal alignments. The housing encloses the motor and transmission components. The sectional views show the motor positioned within the housing, with intermediate coupling elements and a rotational output section aligned with the transmission shaft that extends into the instrument.

[0294] The top view shows the motor positioned within the housing, with the shaft extending forward to connect with the drive assembly. The middle view reveals an alternative sectional arrangement, showing internal components including the motor coupling and a central linking element that secures rotational force transmission. The bottom view reinforces the assembled configuration, demonstrating the alignment of the motor within the housing and the extension of the drive shaft into the surgical shaft. The figure highlights the modular mounting of the drive motor, the arrangement of coupling components, and the structural support provided by the proximal housing, ensuring stability and precision in torque delivery to the distal tool.

[0295] Fig. 46 illustrates the motor and drive assembly according to various embodiments enclosed within the proximal housing, presented in three different sectional and perspective views to highlight the integration of components. In the top view, the motor unit is mounted within the housing, with coupling elements ensuring secure power transmission. The drive shaft projects outward from the housing, aligned for torque transfer to the surgical shaft. The middle sectional view shows the motor aligned with the coupling system, emphasising the positioning of the shaft, bearings, and transmission components within the housing. This cutaway highlights the compact arrangement of the motor relative to the support structure, demonstrating how the internal components are efficiently organised to maximise space and maintain mechanical integrity. The bottom perspective view demonstrates the rearward side of the housing, showing the exit point of the motor shaft and its alignment with external connection features. The robust enclosure provides stability and protection for the motorised components, helping to ensure reliable operation and ease of maintenance. This integrated design supports precise and consistent actuation of the surgical tool during use.

[0296] Fig. 47 illustrates the structural integration of the proximal motor housing with external support and alignment frames, shown in three perspective views.

[0297] In the top view, the motor housing is coupled with structural members that act as stabilising brackets. These elements are designed to secure the housing and align it with the output shaft, ensuring rigid positioning and minimising vibration or movement during operation. The middle view provides a different perspective, emphasising the passage of the motor shaft through the support frame. This highlights how the frame distributes loads while keeping the shaft precisely aligned for efficient torque transfer and reliable mechanical performance. The bottom view shows the completed enclosure, where the support structure is tightly fitted around the motor housing. Fastening points and reinforcement ribs are visible, indicating a modular assembly that can be easily constructed or serviced. The robust design of the support and alignment frames contributes to the overall durability and operational stability of the motor and drive assembly, making it well suited for demanding surgical environments.

[0298] Fig. 48 illustrates the enclosure and integration of the motor drive unit within a protective housing. The top view shows a sectional cut revealing the internal layout. The motor is centrally mounted within a structural casing, supported by alignment frames. The arrangement ensures axial stability of the drive shaft, with internal gearing and couplings positioned to transmit motion efficiently and reliably. The middle and bottom perspective views depict the same assembly with an external cover applied. This cover fully encapsulates the motor and frame, providing both environmental protection and insulation. Circular surface features and recesses on the cover indicate fastening and alignment provisions. The design of the enclosure supports ease of assembly, maintenance, and access to internal components when required. Fig. 49 illustrates the external and sectional features of the motor housing assembly. The top view shows a cross-section through the housing, revealing the circular arrangement of internal structural components. The central axis contains a circular element, representing the motor shaft or central coupling point. Surrounding this are internal partitions that divide the cavity, while rectangular elements are arranged symmetrically to provide alignment and stabilisation. The outer circular boundary represents the protective housing shell. The bottom perspective view depicts the external surface of the cover. A cylindrical port projects outward which may function as a drive shaft output, electrical connection point or fluid channel. Around the port, the surface features recesses, fastening slots, and an additional inset cavity that supports secure assembly and sealing. This configuration ensures robust protection for the internal drive unit while facilitating reliable connection to other system components.

[0299] Fig. 50 illustrates external and sectional details of the motor housing and internal drive assembly. The top image shows a close-up view of the outer casing. A circular opening is visible on the surface, bordered by a defined rim, indicating an access port, mounting location, or sealing point. Adjacent to the port, a set of small parallel slots are included, which may serve purposes such as alignment or fastener engagement. Structural ribs reinforce the casing, contributing to the rigidity and durability of the housing.

[0300] The bottom image provides a sectional cutaway of the internal assembly. The housing encloses the drive mechanism, with a central shaft extending longitudinally and supported by a sleeve for alignment.

[0301] Fig. 51 illustrates a combination of motor drive integration and detailed jaw assembly views. The top image shows a sectional cutaway of the housing. The casing encloses the internal components.

[0302] The lower sequence of images illustrate the end-effector jaws in different orientations. The images show the fixed body portions and the movable jaws. The second image shows a top-down view, with alignment holes and cavities for pivot mounting. The third and fourth images illustrate the jaws in different angular positions, showing a serrated gripping surface for enhanced tissue engagement. The final image demonstrates an open configuration with one jaw rotated outward, revealing the pivoting mechanism and interaction between the fixed and movable parts.

[0303] Fig. 52 illustrates the detailed structure and scale of the end-effector jaw assembly. The top image shows a perspective view of the jaw mechanism, with the fixed body and the movable jaw. The movable jaw is pivot-mounted, with a cylindrical pin attachment projecting laterally, allowing controlled articulation relative to the fixed body. The middle image provides a front view of the jaw assembly. It highlights the circular central channel running through the body, which accommodates the pivot and drive elements. The fixed body is symmetrically shaped, ensuring stability, while the movable jaw is positioned to close against the lower section for gripping or cutting action.

[0304] The bottom image provides a scale comparison, showing a photographic reference of a similar end-effector with pixel-based measurements. The overall width is noted as 3.4 mm, while the narrower section of the jaw tip measures 1.7 mm. This dimensional data demonstrates the compact size of the assembly, emphasising its suitability for minimally invasive surgical applications.

[0305] Fig. 53 illustrates dimensional aspects of the jaw assembly according to an embodiment, highlighting the compact design and scale of the instrument tip. The top image shows a photographic reference of a surgical jaw with serrated gripping edges, providing a real-world visual context for the size and functional features of the assembly. Below this, a technical drawing provides pixel-based measurements of critical dimensions, allowing for precise assessment of the instrument’s proportions. The total width of the assembly is shown as 4.5 mm, with the inner width of the jaw body measured at 3.4 mm and a narrower section, corresponding to the tip channel, measured at 1.7 mm. These measurements demonstrate the miniaturisation achieved in the design, making the jaw assembly suitable for use in minimally invasive surgical procedures where access is limited.

[0306] The bottom image shows a 3D CAD view of the jaw assembly, offering a detailed perspective on the spatial arrangement of the components. An indicated dimension line shows the available clearance within the jaw mechanism, measuring 4.8 mm. This clearance is important for ensuring that the mechanical operation of the jaw is not impeded and that there is sufficient space for the alignment and movement of associated drive elements, such as actuation cables or linkages. The CAD view also allows for visualisation of the relationship between the fixed and movable parts of the jaw, supporting further optimisation of the design for strength, reliability and ease of assembly.

[0307] Fig. 54 illustrates the dimensional and geometric characteristics of the instrument tip, along with its integration into the shaft and drive housing. At the top, the jaw structure is shown with an internal width ranging from 3.2 to 4.0 mm and a clearance of 1.9 mm near the hinge. This design provides a balance between gripping force and compactness, ensuring that the instrument can exert sufficient force for effective tissue manipulation while maintaining a slender profile suitable for minimally invasive procedures. The central sketch depicts the jaw in profile, with an opening angle of 45 degrees, a tip-to-hinge distance of 2.36 mm, and a height of 3.4 mm.

[0308] The figure also compares different relationships between the instrument tip and shaft. An equal tip width may be utilised as it aligns properly with the shaft, improving handling consistency and ensuring seamless integration with the drive housing.

[0309] Fig. 55 provides a comprehensive analysis of the mechanical forces acting on the jaw mechanism, using diagrams that depict geometry, trigonometric relationships and force resolution. The jaws are illustrated in various states of actuation, with arrows indicating the directions and magnitudes of applied forces, reaction forces, and tissue resistance.

[0310] The diagrams demonstrate how the input force delivered by the actuation cables is converted into rotational motion at the hinge, resulting in a force applied to the tissue. Trigonometric principles are used to decompose these forces into their components, clarifying how the angle of application, lever arm length, and jaw geometry influence the effective force at the tip. The illustrations also address concepts such as moment arms and the impact of different jaw opening angles, highlighting how these factors affect the instrument’s gripping efficiency and strength.

[0311] Supplementary sketches in the lower right corner present enlarged vector diagrams and symbolic representations of the force balance within the mechanism. These visual aids support calculations of mechanical advantage and operational efficiency, helping to ensure that the instrument achieves reliable clamping or cutting action without imposing excessive loads on the actuation system.

[0312] Fig. 56 shows a sequence of assembly steps for the housing and internal components of the device according to an embodiment. The images capture a set of modular parts laid out on a work surface, demonstrating how the structural sections are brought together to form the complete assembly. In the left image, the round upper cover with internal slots and cutouts is being aligned with intermediate housing parts, which include mounting features and recesses designed to hold the internal mechanism securely in place. Multiple subcomponents such as circular inserts, guide structures, and fasteners are visible, each serving a specific function in enclosing, supporting and stabilising the actuator system.

[0313] The right image illustrates the process of positioning the cover onto the underlying housing segments. This step highlights how the different structural shells are designed to fit together precisely, locking the internal drive components securely while still providing access points for essential connections, such as the actuation shaft and electrical interfaces. The arrangement ensures that the internal mechanisms are protected and properly aligned, while also allowing for straightforward assembly and disassembly.

[0314] The layout of parts shows the disassembled state of the mechanism, emphasising the modularity of the design and the relative simplicity of reassembly. This modular approach facilitates maintenance, repair, and potential upgrades, as individual components can be accessed and replaced without the need to dismantle the entire device.

[0315] Fig. 57 illustrates the design and specification of a flexible segment assembly, showing both the structural arrangement and key engineering dimensions. The main visualisation depicts a series of interconnected vertebra-like elements that form a bending section, which is controlled by tension cables routed through the assembly. The drawing highlights how these cables are anchored and guided, enabling controlled deflection of the segment and allowing it to bend up to 120 degrees. This flexible section provides the instrument with the ability to navigate complex anatomical pathways and reach target sites that would be inaccessible with rigid instruments.

[0316] The annotations detail various preferred dimensions, including a 5.0 mm radius of curvature, 1.5 mm diameter central and 0.5 mm outer apertures to facilitate smooth articulation between the vertebra-like elements. A cutaway of the distal portion demonstrates how additional components, such as an endoscope or instrument shaft with diameters ranging from 1.5 mm to 3.5 mm, can be integrated into the system. This integration supports multifunctionality, allowing the flexible segment to accommodate imaging devices, suction or irrigation lines, or other surgical tools.

[0317] Fig. 58 illustrates anatomical access pathways and working envelopes relevant to the deployment of the instrument in joint surgery. Multiple overlays of arcs and ellipses depict the angular ranges and trajectories achievable in axial, sagittal, and perspective planes. These trajectories correspond to the sweep of the instrument tip within confined anatomical spaces, such as the shoulder joint, and demonstrate the instrument’s ability to reach various intra-articular targets.

[0318] The diagrams are combined with clinical reference images, including endoscopic views of arthroscopic portals. Measurements of intra-articular clearances, such as gaps of 11 mm, 18 mm, and 7.5 mm, are annotated on the images to show the spatial constraints in which the device must operate. Comparative outlines illustrate how the instrument’s reach aligns with existing anatomical landmarks and surgical approaches, emphasising safe entry zones and optimal working corridors for minimally invasive access. The integration of schematic geometry with live surgical views highlights how design tolerances, degrees of motion, and tool orientation translate directly into surgical access. This figure bridges the gap between engineering design intent and real-world operative feasibility, underscoring the instrument’s compatibility with minimally invasive procedures and its ability to navigate complex joint anatomy.

[0319] Fig. 59 illustrates the surgical workspace and clinical applicability of the instrument in relation to shoulder anatomy and arthroscopic procedures. On the left, the overlaid arcs and ellipses again map the potential ranges of motion of the tool tip, showing how these align with anatomical access corridors. The geometric traces demonstrate how the instrument can be steered or articulated to reach critical intraarticular zones.

[0320] On the right, clinical reference material provides direct anatomical context. The upper section shows both a schematic diagram and a cadaveric dissection of the glenoid and surrounding soft tissue, highlighting landmarks such as the supraspinatus (SS), long head of the biceps tendon (LHBT), and humeral head (HH). Below, endoscopic images illustrate how these structures appear in a surgical setting, demonstrating tool positioning and tissue clearance.

[0321] The lower portion of the figure emphasises labral repair workflows. Stepwise arthroscopic images show preparation of a labral tear, suture passage and anchor placement. Measurements, such as 4.8 mm, 5.83 mm and 7.33 mm, provide quantitative detail on portal access, anchor dimensions, and working space tolerances. These numerical annotations align the engineering design of the instrument with the practical requirements of surgical repair techniques.

[0322] Further alternative embodiments are contemplated in which the distal end effector is provided with interchangeable jaw modules. In such embodiments, the jaws may be detached from the main shaft and replaced with alternative jaw types, such as needle holders, micro-scissors, or cautery tips, depending on the surgical procedure to be performed. The interchangeable modules may be secured by a bayonet fitting, threaded connection, or magnetic coupling, allowing rapid exchange during surgery without the need for additional tools.

[0323] In another alternative embodiment, the actuation mechanism within the shaft may be configured to provide not only opening and closing of the jaws, but also rotational movement about the longitudinal axis of the shaft. This may be achieved by incorporating a rotatable drive cable or a miniature motor at the distal end, enabling the surgeon to rotate the end effector for improved access and manipulation of tissue within confined anatomical spaces. A further embodiment provides for the integration of one or more sensors within the jaws or the shaft. These sensors may include force sensors, temperature sensors, or electrical impedance sensors, allowing real-time feedback to the surgeon regarding tissue properties, applied force, or the presence of specific tissue types. The sensor data may be displayed on a user interface or used to trigger safety cut-offs in the event of excessive force or temperature.

[0324] Alternative embodiments may also include a fluid delivery or suction channel integrated within the shaft, terminating at the distal end effector. This allows for irrigation, aspiration, or the delivery of therapeutic agents directly to the surgical site. The fluid channel may be arranged concentrically with the actuation mechanism or offset within the shaft wall, and may be controlled by a valve mechanism at the proximal end.

[0325] In yet another embodiment, the instrument may be configured for wireless communication with a remote control unit or robotic system. The actuation of the jaws, wrist articulation, and sensor feedback may be transmitted wirelessly, reducing the number of physical connections required and improving the ergonomics and sterility of the surgical field.

[0326] It is also envisaged that the instrument may be manufactured in a range of sizes and materials, including single-use disposable versions for specific procedures or patient populations. The shaft and jaws may be formed from stainless steel, titanium, or high- strength polymers, with surface coatings to enhance biocompatibility, reduce friction, or provide antimicrobial properties.

[0327] While particular embodiments have been illustrated and described, it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the scope of the present invention.

Claims

Claims1. An actuated wrist mechanism configured to move and / or operate a surgical tool, wherein the articulated wrist mechanism comprises: an abutment portion having a first abutment surface which is configured to abut, in use, against an abutment surface of a surgical tool; and one or more tendons configured to interconnect, in use, a portion of the surgical tool and an actuator; wherein, in use, actuation of the actuator causes force to be transmitted to the surgical tool via the one or more tendons thereby causing the surgical tool to move and / or operate.

2. An actuated wrist mechanism as claimed in claim 1, further comprising one or more actuators for actuating the one or more tendons.

3. Apparatus comprising: an actuated wrist mechanism as claimed in claim 1 or 2; and a surgical tool abutted against the actuated wrist mechanism.

4. Apparatus as claimed in claim 3, wherein the first abutment surface comprises a concave abutment surface and wherein the abutment surface of the surgical tool comprises a convex abutment surface.

5. Apparatus as claimed in claim 3, wherein the first abutment surface comprises a convex abutment surface and wherein the abutment surface of the surgical tool comprises a concave abutment surface.

6. Apparatus as claimed in any of claims 3, 4 or 5, wherein the surgical tool and the actuated wrist mechanism form a ball and socket arrangement or interface.

7. Apparatus as claimed in any of claims 3-6, wherein the surgical tool is configured to: (i) pitch up and / or pitch down; and / or (ii) yaw left and / or yaw right; and / or (iii) roll or rotate in a first direction and / or roll or rotate in a second direction, wherein the second direction is opposed to the first direction; and / or (iv) simultaneously pitch and yaw.

8. Apparatus as claimed in any of claims 3-7, wherein the surgical tool is configured to be positively actuated by the one or more tendons.

9. Apparatus as claimed in claim 8, wherein the one or more tendons are connected to one or more motors, wherein the one or more motors are configured to transmit force to the surgical tool via the one or more tendons.

10. Apparatus as claimed in claim 9, further comprising a force measuring device configured to measure the force transmitted to the surgical tool via the one or more tendons.

11. Apparatus as claimed in claim 10, wherein the force measuring device is configured to measure a back electromotive force (“EMF”) experienced by the one or more motors, wherein the measured back electromotive force correlates with the force(s) exerted on the surgical tool and / or experienced by the surgical tool.

12. Apparatus as claimed in any of claims 3-11, wherein the actuated wrist mechanism and / or the surgical tool further comprise a cannula or fluid flow channel.

13. Apparatus as claimed in claim 12, wherein the cannula or fluid flow channel is configured to provide one or more suction channels.

14. Apparatus as claimed in claim 12 or 13, wherein the cannula or fluid flow channel is configured to provide one or more irrigation channels.

15. Apparatus as claimed in any of claims 12, 13 or 14, further comprising one or more integrated suction and irrigation channels.

16. Apparatus as claimed in claim 15, wherein the one or more integrated suction and irrigation channels are configured to enable fluid management at an instrument tip of the surgical tool.

17. Apparatus as claimed in claim 15 or 16, wherein the one or more integrated suction and irrigation channels are configured to capture tissue and / or provide a suture port and / or provide a clear surgical field.

18. An arthroscopic surgical instrument comprising apparatus as claimed in any of claims 3-17.

19. A method comprising: providing apparatus as claimed in any of claims 3-17; and actuating the actuated wrist mechanism in order to move and / or control the surgical tool.

20. A method of surgery comprising a method as claimed in claim 19.

21. A method of performing arthroscopic surgery comprising a method as claimed in claim 20.

22. A surgical instrument comprising: an actuated wrist mechanism comprising a shaft having a first abutment surface, and wherein the shaft comprises one or more grooves or channels; a surgical tool having a second abutment surface, wherein the first abutment surface is abutted against the second abutment surface and wherein the surgical tool further comprises one or more recesses or sockets; one or more tendons, each tendon having an end portion, wherein each end portion is located within one of the one or more recesses or sockets; and one or more motors for actuating the one or more tendons, wherein the one or more motors are configured to transmit force to the surgical tool via the one or more tendons in order to move and / control the operation of the surgical tool in use.

23. A surgical instrument as claimed in claim 22, further comprising a force measuring device for measuring the back electromotive force (“EMF”) generated by the one or more motors, wherein the force measuring device generates an output or signal indicative of the force(s) exerted by the surgical tool and / or the force(s) experienced by the surgical tool.

24. Apparatus comprising: a mechanism configured to control the movement and / or operation of an attachment, wherein the mechanism comprises a shaft portion comprising a collar, wherein the collar comprises a first abutment surface and wherein the shaft portion further comprises one or more grooves; an attachment comprising a second abutment surface, wherein the second abutment surface abuts against the first abutment surface; one or more tendons, wherein each tendon is arranged in one of the one or more grooves, and wherein each tendon comprises an end portion; one or more motors for actuating the one or more tendons; and a control system configured to cause the one or more motors to actuate one or more of the tendons so as to move and / or operate the attachment.

25. A robot comprising apparatus as claimed in claim 24.

26. A surgical robot comprising apparatus as claimed in claim 24.

27. An actuated wrist mechanism configured to control the movement and / or operation of a surgical tool, wherein the actuated wrist mechanism comprises: a shaft portion comprising a collar, wherein the collar comprises a first abutment surface which is configured to abut, in use, against an abutment surface of a surgical tool; wherein the shaft portion further comprises one or more grooves;one or more tendons, wherein each tendon is arranged in one of the one or more grooves, and wherein each tendon comprises an end portion; wherein, in use, the one or more of the tendons are configured to control the movement and / or operation of a surgical tool.

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