Torque transmission unit

Abstract

Various embodiments provide a torque transmitting unit for rotating a flexible shaft. The torque transmitting unit includes an elongate track (120) defining a track channel and a key (122) attachable to the flexible shaft and movable along the track channel. The key and the elongated track are configured to engage each other to inhibit relative rotation of the key and the track channel. The torque transmitting unit is actuatable to selectively adjust an axial position of the key relative to the track channel. Some other embodiments provide a kit of parts.

Description

Technical Field

[0001] The present invention relates to a torque transfer unit for rotating an electrosurgical instrument, for example during a surgical procedure. The electrosurgical instrument can be used to deliver radiofrequency energy and / or microwave frequency energy into biological tissue. Background Art

[0002] Surgical resection is a means of removing some parts of an organ from a human or animal body. Such organs may be highly vascularized. When cutting (segmenting or transecting) tissue, small blood vessels called arterioles may be damaged or ruptured. First there is bleeding, followed by a coagulation cascade, i.e., the blood turns into clots in an attempt to block the bleeding point. During surgery, it is expected that the patient loses as little blood as possible, so various devices have been developed in an attempt to achieve bloodless cutting. With regard to endoscopic procedures, bleeding is not expected to occur, and bleeding needs to be handled in a convenient way because the blood flow may block the doctor's line of sight, which may delay the surgical procedure and potentially lead to the need to terminate the procedure and switch to another method, such as laparotomy.

[0003] Electrosurgical generators are common in hospital operating rooms and are often used in open and laparoscopic procedures, and are increasingly used with surgical endoscopic devices such as endoscopes. In endoscopic procedures, electrosurgical accessories are typically inserted through a lumen inside the endoscope. This lumen is narrow in caliber and long in length, considering the equivalent access channel for laparoscopic surgery.

[0004] It is known that microwave frequency energy can be used to stop bleeding (ie, to seal a ruptured blood vessel by promoting blood clotting). Devices are known that radiate microwave energy from the edge of a planar transmission line to cause localized tissue ablation or coagulation.

[0005] In addition, it is known to use radio frequency (RF) energy instead of a sharp blade to cut biological tissue. The method of cutting using RF energy operates on the following principle: when the current passes through the tissue matrix (aided by the ionic content of the cells and the electrolytes between the cells), the resistance to the flow of electrons across the tissue generates heat. In fact, the instrument is arranged to apply an RF voltage across the tissue matrix, which is sufficient to generate heat within the cells to evaporate the water in the tissue. However, due to this increasing dehydration, especially adjacent to the RF emission area of ​​the instrument (which has the highest current density of the current path through the tissue), the direct physical contact between the tissue and the instrument may be lost. The applied voltage then appears as a voltage drop across this small gap, which causes ionization in the gap, which forms a plasma. Compared with tissue, plasma has a very high volume resistivity. The energy supplied to the instrument maintains the plasma, that is, completes the circuit between the instrument and the tissue. Volatile materials entering the plasma can evaporate and are therefore felt to be a tissue dissection plasma.

[0006] GB 2 523 246 describes an interface connector for integrating (i) a fluid feed, (ii) a needle moving mechanism and (iii) an energy feed (e.g., a line for supplying RF energy and / or microwave energy) into a single core line assembly. The line assembly can be sized to pass through an instrument channel of a conventional endoscope. A torque transfer unit is also described for permitting controlled rotation of the line assembly within the instrument channel of an endoscope.

[0007] The present invention has been conceived in view of the above considerations. Summary of the invention

[0008] The present invention provides a development of the concepts discussed in GB 2 523 246 .

[0009] Most generally, the inventors have developed a modified torque transfer unit for rotating a flexible shaft, such as for rotating an instrument tip (e.g., an electrosurgical instrument tip) connected to the flexible shaft. The flexible shaft can be sized to pass through an instrument channel of an endoscopic surgical device and can be connected to the instrument tip at its distal end.

[0010] According to a first aspect of the present invention, there is provided a torque transfer unit for a rotating flexible shaft, the torque transfer unit comprising: an elongated track defining a track channel; and a key attachable to the flexible shaft and movable along the track channel, the key and the elongated track being configured to engage with each other to inhibit relative rotation of the key and the track channel; wherein the torque transfer unit is actuatable to selectively adjust the axial position of the key relative to the track channel.

[0011] This arrangement effectively separates the rotational control of the flexible shaft from the axial (longitudinal) adjustment of the torque transfer unit, thereby helping the torque transfer unit to firmly hold the flexible shaft while mitigating excessive damage to the shaft. On the one hand, because the track and key are configured to inhibit (e.g., prevent) relative rotation of the key within the track channel, they help ensure that the user's rotational force is effectively transmitted to the flexible shaft without causing the shaft to slip relative to the torque transfer unit. On the other hand, because the torque transfer unit can be actuated to selectively adjust (move and fix) the axial position of the key relative to the track channel, it enables the axial (longitudinal) position of the torque transfer unit on the flexible shaft to be adjusted to a position that is convenient for use. Because the cooperation of the key within the elongated track helps prevent rotational slippage, the torque transfer unit can use less force to grip the shaft, for example, compared to an arrangement that relies on a strong grip on the shaft to provide rotational and axial control. This in turn can help reduce strain and damage to the flexible shaft because the torque transfer unit can apply lower forces to the shaft.

[0012] As described above, a torque transfer unit can be used to rotate the tip of an electrosurgical instrument connected to a flexible shaft at the distal end of a surgical endoscopic device (e.g., an endoscope) by transferring a user's rotational force to the flexible shaft, and the torque transfer unit is arranged to apply a gripping force along the length of the flexible shaft located outside the proximal end of the surgical endoscopic device.

[0013] As used herein, the phrase "elongated track" can refer to a component configured to extend axially along the length of a flexible shaft. The elongated track can be tubular (e.g., extending completely around the flexible shaft and the key). Alternatively, the elongated track can extend only around a portion of the key, such as as a U-shaped track or other shape. The track channel can have a smooth profile along its entire length (e.g., as an elongated cuboid) to allow the key to be adjusted over a continuous range of positions. Alternatively, the track channel can include one or more axial protrusions for fixing the axial position of the key, as will be discussed further herein.

[0014] The elongated track may also be referred to as a "key runner". In arrangements where the elongated track is tubular, the key may be slidable within the track channel. In variant arrangements (e.g., for tracks that do not extend completely around the flexible shaft and key), the key may be slidable along the track.

[0015] The key may be movable relative to (along / within) the (first) channel of the elongated track. The key may be fixedly attached to the flexible shaft. It will therefore be appreciated that, in use, the track may be the element that actually moves (relative to the key) to adjust the position of the torque transfer unit, while the key (and the flexible shaft) may remain stationary. Optionally, the key is fixed / adhered (e.g. glued, crimped) to the shaft, and will therefore remain stationary relative to the shaft when in use.

[0016] The key may be formed of any suitable material (eg, metal, plastic). For example, the key may be formed of a deformable material (eg, metal) for crimping to a shaft.

[0017] As discussed above, the key and the elongated track are configured to engage one another to inhibit (e.g., prevent) relative rotation of the key and the track channel. In this regard, "rotation" refers to a plane of rotation that is perpendicular to the longitudinal axis of the flexible shaft. In other words, the key and the elongated track are configured to rotate together (the same angle) about the longitudinal axis of the flexible shaft.

[0018] The key and the elongated track may be mutually configured to engage with each other in any suitable manner to inhibit their relative rotation. The key may include one or more radial engagement structures configured to engage with corresponding one or more radial engagement structures of the elongated track to inhibit relative rotation of the engagement structures.

[0019] As used herein, the phrase "engagement structure" may refer to a protrusion, edge, corner, pin, rib, groove, notch, or other abutment surface that is configured to engage a corresponding surface / structure of another component to prevent relative movement therewith. For example, a key may have one or more protrusions (e.g., corners) that are configured to engage or interlock with corresponding one or more protrusions (e.g., corners) of an elongated track.

[0020] A "radial" engagement structure can be configured to prevent relative radial movement, while an "axial" engagement structure can be configured to prevent relative axial movement. Thus, the phrase "radial engagement structure" can refer to an engagement structure (rib, groove, corner, etc.) formed at a specific position around the circumference / periphery of a first component (e.g., a key) to provide the first component with a radius that varies around its periphery (e.g., as measured from the center of the flexible shaft). Thus, the radial engagement structure can act as a boundary / flange that inhibits relative radial movement of the two components when it engages against a corresponding structure of a second component (e.g., an elongated track). The radial engagement structure can extend (e.g., continuously) in the axial direction of the component to inhibit rotation along the entire length of the component. The radial engagement structure can be, for example, a corner of a specific cross-sectional shape, as will be discussed further herein.

[0021] The torque transfer unit can be actuated in any suitable manner to selectively adjust the axial position of the key relative to the track channel. For example, the torque transfer unit can include a clamping element that is connectable (e.g., connected) to the elongated track and can be actuated to selectively adjust (move and fix) the axial position of the key relative to the track channel. The clamping element can be actuable between: a clamping position for clamping to the flexible shaft to prevent axial movement of the elongated track relative to the key; and a loosening position for loosening the flexible shaft to allow axial movement of the elongated track relative to the key.

[0022] Advantageously, providing a separate clamping element may allow the key to be adjusted in a continuous range of positions. When the clamping element is in the loosened position, the torque transfer unit can slide freely along the length of the flexible shaft to a position convenient for use. The loosened position may also be referred to herein as the "released position". Once in the desired position, the torque transfer unit may be secured in place by driving the clamping element into the clamped position.

[0023] In variant embodiments, the torque transfer unit may not require different clamping elements. For example, the elongated track itself may be actuatable to selectively adjust the position of the key without requiring a clamping element to fix the position of the key relative to the track. For example, the elongated track may include one or more axial engagement structures that are configured to inhibit movement of the key and may be deformable to selectively allow the key to move past the one or more engagement structures (as will be further discussed herein).

[0024] It may be advantageous to position the torque transfer unit as close to the endoscopic device as possible in order to provide optimal control of the instrument tip at the distal end of the endoscopic device. In use, when the distal tip of the electrosurgical instrument is properly positioned relative to the distal end of the flexible endoscope within the field of view of the endoscope video monitor, the endoscopist intends to clamp and lock the torque transfer unit at the exit point of the flexible shaft from the endoscope working channel and adjacent to the endoscope XY control. When clamped in this position, the torque transfer unit can provide finger and thumb rotational and longitudinal position control of the instrument distal tip.

[0025] Optionally, the clamping element has a gripping surface for facilitating gripping by a user. The gripping surface may include one or more notches, projections and / or concave profiles that are sized to facilitate gripping by the user. The gripping surface may be formed by a viscous and / or deformable material (e.g., silicone). The gripping surface may further improve ease of use, for example, to facilitate actuation of the clamping element. The gripping surface may include one or more notches / projections extending in an axial direction. This is particularly useful for assisting gripping in embodiments where the clamping element is rotatably driven around the axis of the shaft.

[0026] The clamping element can be configured to clamp onto the flexible shaft in any suitable manner. Optionally, the clamping element can be rotatably actuated between a clamped position and a released position, for example by rotating the clamping element around the flexible shaft. The clamping element can be sized to be rotatably actuated by a user's thumb and index finger. Rotatable actuation can provide an intuitive and / or one-handed mechanism to actuate the clamping element, and can improve ease of use, for example, compared to an arrangement that requires the clamping element to be hingedly actuated onto the flexible shaft.

[0027] Optionally, the clamping element defines a clamping channel through which the flexible shaft extends, wherein the clamping element is actuatable to selectively tighten (grasp) the clamping channel to the flexible shaft. By providing a clamping channel extending around the flexible shaft (e.g., around substantially the entire circumference thereof), the clamping element can improve the grip around the flexible shaft and evenly distribute all forces around the shaft.

[0028] When present, the clamping channel may be axially spaced apart and / or concentric with the track channel.

[0029] The clamping element may be a collet-type clamp. As used herein, the term 'collet' is used in its ordinary sense to refer to a sub-type of chuck that forms a collar around the object to be held and applies a strong clamping force to the object while tightening it.

[0030] The collet-type clamping element may include a collet element defining a clamping channel of the flexible shaft, and an actuating element (e.g., a threaded actuating element or a spring-loaded actuating element) that can be actuated to selectively tighten or loosen the collet element around the flexible shaft (and thus tighten or loosen the clamping channel). The collet element may be distinct from the actuating element, i.e., they may be formed as separate components. Alternatively, the clamping element may be a collet-type clamp of integral construction, such as a torsion spring, which defines a clamping channel therethrough and has an axially protruding end that can be actuated (e.g., squeezed) to change the size of the clamping channel.

[0031] Optionally, the clamping element is a threaded chuck type fixture. For example, the actuating element may have a threaded surface (e.g., an internal threaded surface) and the chuck element may have a cooperating threaded surface (e.g., an external threaded surface). In use, the threads of the actuating element engage with the threads of the chuck element so that rotation of the actuating element causes the chuck element to tighten against the flexible shaft. The chuck and / or the drive element may have a tapered form to facilitate such tightening. In addition, the actuating element may include a gripping surface on its outer surface to facilitate rotation by the user (which may be configured similarly to the gripping surface discussed above). This may help to firmly hold the flexible shaft in a simple and easily adjustable manner.

[0032] Optionally, the clamping element comprises a resilient member (eg a torsion spring) resiliently biased towards the clamped position. This may improve ease of use and help ensure that the torque transfer unit remains axially fixed when in use.

[0033] For example, in an embodiment where the clamping element is a spring-loaded collet-type clamp, the clamping element may include a torsion spring that defines a clamping channel. The clamping element may include a lever that is connected to one end of the torsion spring and can be actuated to loosen the spring to increase the size of the channel. Preferably, the clamping element includes a single lever that can be actuated by rotating around the axis of the flexible shaft. The user only needs to gently push with the thumb to make simple adjustments. Alternatively, the clamping element may include two levers (one lever is connected to each end of the torsion spring) and can be actuated by squeezing the levers together (e.g., using two fingers). This may also be referred to as a "squeeze and release" mechanism.

[0034] In alternative embodiments, the clamping element may not be a collet-type clamp. For example, the clamping element may instead include a hinge clamp. For example, the clamping element may include a first jaw and a second jaw, the first jaw being movable (e.g., pivotable) relative to the second jaw to clamp onto the flexible shaft; and a retaining member that is actuatable to retain the first jaw in a clamped position or release the first jaw from a clamped position.

[0035] The first jaw and the second jaw may together form a generally U-shaped member. The U-shaped member may include a hole (between the first jaw and the second jaw) for delivering a flexible shaft therethrough.

[0036] The retaining element may be configured to snap fit onto the first jaw to hold the first jaw in the clamped position. The retaining element may be configured to extend from one end of the second jaw toward the free end of the first jaw (i.e., spanning the open end of the U-shaped member), and may include a hook for engaging (snap fitting) against the free end of the first jaw in the clamped position. Optionally, the retaining element is located at the proximal end of the torque transfer unit. This may facilitate simple one-handed operation. In use, the retaining element may be simply pulled back (in the proximal direction) to release the hook from the first jaw, thereby allowing the first jaw to move away from the second jaw, thereby loosening the flexible shaft.

[0037] In this embodiment, the clamped position may also be referred to as the "closed" position (referring to a position where the jaws are close together), and the released position may also be referred to as the "open" position (referring to a position where the jaws are further apart).

[0038] Optionally, the retaining element and the U-shaped member are integrally formed (eg as a single plastic element).Such a clamping element may be relatively cheap and easy to manufacture.

[0039] Optionally, the clamping element (e.g., the retaining element and / or the first jaw) can be flexible so that the retaining element and / or the first jaw can be elastically deformed toward / away from the second jaw to actuate between the clamped position / released position. Optionally, the first jaw can be elastically biased toward the release (open) position. This can facilitate the one-handed release of the clamping element from the clamped position, because when the retaining element is released from the first jaw, the first jaw can immediately elastically return (spring back) to the open position.

[0040] The first jaw and / or the second jaw may include one or more protrusions (e.g., teeth) configured to abut against the flexible shaft when the clamping element is in the clamping position. This can further improve the grip of the clamping element, thereby forming a tight friction fit against the flexible shaft to prevent it from moving. The first jaw and / or the second jaw (including any teeth thereof) may together define a clamping channel, as described above. Optionally, the protrusions (teeth) may have a curved inner surface for engaging the circumference of the flexible shaft. This may help to improve the grip around the flexible shaft. Optionally, the first jaw and / or the second jaw may include teeth that are axially offset (staggered, interlocked) relative to each other, such as so that one of the jaws includes a tooth that can be axially positioned between a pair of teeth of the other jaw. This may help to squeeze / compress the flexible shaft between the jaws.

[0041] Optionally, the torque transfer unit may further include an outer cover surrounding the elongated track, the cover including a gripping surface to facilitate gripping by a user. This may help to further improve the user's control of the device. The gripping surface may be configured similarly to that described above with respect to the clamping element, for example having one or more notches, protrusions and / or concave profiles, the dimensions of which are set to facilitate gripping by a user. Alternatively or in combination, the gripping surface may include a deformable or viscous material (e.g., silicone) to facilitate gripping.

[0042] Optionally, the outer surface of the elongated track and the inner surface of the cover can be configured to engage with each other to inhibit (e.g., prevent) rotation and / or axial movement of the elongated track relative to the cover. The control of the torque transfer unit is further improved by inhibiting the track from sliding within the cover, thereby more effectively transmitting the user's rotational force and / or axial force to the flexible shaft.

[0043] The elongated track and the cover may be configured to engage with each other in any suitable manner. For example, the outer surface of the elongated track and / or the inner surface of the cover may include one or more engagement structures similar to the structures discussed above with respect to the key and the elongated track.

[0044] The cover may be formed of a relatively rigid or deformable material. Thus, the cover may have a preformed engagement structure (e.g., formed of a relatively rigid material (e.g., plastic)) that is configured to engage with / against the engagement structure of the elongated track, or the cover may be formed of a deformable material that is configured to deform against the elongated track to form a tight fit against its engagement structure.

[0045] In some embodiments, the torque transfer unit can be actuated without the need for a clamping element. For example, in some embodiments, the torque transfer unit can be actuated by sliding an elongated track relative to the key, thereby overcoming the resistive friction between the axial engagement structure and the key. For example, optionally, the torque transfer unit may include an axial engagement structure (or multiple axial engagement structures) along the track channel. The axial engagement structure can be configured in a manner similar to the axial engagement structure discussed above, for engagement against the key to inhibit relative axial movement of the key across the engagement structure. The elongated track (e.g., the axial engagement structure) can be elastically deformable (e.g., formed of silicone) to selectively allow the axial engagement structure to move across the key by deforming the elongated track. In other words, the elongated track can be elastically deformed between a non-deformed state and a deformed state, in which the axial engagement structure inhibits the relative movement of the elongated track past the key, and in the deformed state, the elongated track can slide over the key (e.g., due to the elastic deformation of the axial engagement structure enabling it to slide over the key).

[0046] Thus, the torque transfer unit can be actuated simply by sliding the elongated track axially relative to the flexible shaft. When the elongated track is pulled / pushed with sufficient force, the force of the key against the axial engagement feature can deform the axial engagement feature, allowing it to move past the key to adjust the axial position of the torque transfer unit. A torque transfer unit configured in this way can be relatively simple and inexpensive to manufacture, as it does not require additional components in the form of clamping elements to adjust the position of the key.

[0047] Alternatively, the elongated track may include multiple axial engagement structures along the track channel. For example, the track channel may have a wavy (e.g., scalloped or sawtooth) profile for engagement against a key (which may have a complementary profile). Such an arrangement with multiple engagement structures may allow position adjustment along multiple discrete increments. In contrast, the clamping elements described above may allow continuous position adjustment.

[0048] The elongated track can be formed as part of an integral grippable member that is shaped on its inner surface to provide a track channel and shaped on its outer surface to provide a gripping surface. The integral member can include features similar to the "outer cover" mentioned above, except that the grippable member is integral with the elongated track.

[0049] Optionally, the torque transfer unit may further include a flexible shaft. The key may be attached (e.g., permanently attached, fixed) to the flexible shaft. The key may be attached to the flexible shaft in any suitable manner. For example, the key may be a collar assembled around the circumference of the flexible shaft, such as by a tight interference fit. Alternatively, the key may be attached to the flexible shaft in other ways, such as by using an adhesive and / or welding. By attaching the key to the flexible shaft, the torque transfer unit may prevent the key from sliding around the flexible shaft, thereby improving rotational control.

[0050] It should be noted that if the key is permanently attached to the flexible shaft, the position of the key on the flexible shaft will limit the extent to which the torque transfer unit can be axially adjusted along the flexible shaft. Therefore, in order to facilitate use with a variety of surgical endoscopic devices (which may each have different lengths and thus require the torque transfer unit to be in different positions on the flexible shaft), it may also be necessary to provide a parts kit having multiple flexible shafts and multiple torque transfer units, wherein each key of each torque transfer unit is permanently attached to the corresponding flexible shaft at a different position along the flexible shaft.

[0051] The flexible shaft may also be referred to herein as a "flexible cannula". The flexible shaft may have coaxial tubing and / or fluid channels therethrough to deliver electromagnetic energy and / or fluid to biological tissue. The shaft may be connected to an electrosurgical instrument tip at its distal end. As used herein, the term "proximal end" may refer to an area distal to the instrument tip. Conversely, the term "distal end" may refer to an area located closer to the instrument tip.

[0052] The electrosurgical instrument tip may be any device that is arranged in use to treat biological tissue using RF EM energy and / or microwave frequency EM energy. The electrosurgical instrument may use RF EM energy and / or microwave frequency EM energy for any or all of resection, coagulation and ablation. For example, the instrument may be a resection device as disclosed in GB 2 523 246 A, but may alternatively be any of a pair of microwave forceps, a snare that radiates microwave energy and / or couples RF energy, and an argon beam coagulator.

[0053] In this document, radio frequency (RF) may mean a stable fixed frequency in the range of 10kHz to 300MHz, and microwave frequency may mean a stable fixed frequency in the range of 300MHz to 100GHz. RF energy should have a frequency high enough to prevent the energy from causing nerve stimulation and a frequency low enough to prevent the energy from causing tissue blanching or unnecessary thermal margins or damage to tissue structures. Preferred nominal frequencies for RF energy include any one or more of 100kHz, 250kHz, 400kHz, 500kHz, 1MHz, 5MHz. Preferred nominal frequencies for microwave energy include 915MHz, 2.45GHz, 5.8GHz, 14.5GHz, 24GHz.

[0054] Optionally, the flexible shaft may include a reinforcement section that is harder or thicker than the distal end section of the flexible shaft (e.g., a section that can be inserted through a surgical endoscopic device). A key may be attached to the reinforcement section of the flexible shaft. This arrangement may help to further reduce stress or damage to the shaft. In addition, the reinforcement section may help to provide better rotational control of the instrument because the harder / thicker section may be less prone to rolling up, thereby helping to ensure that the rotation of the shaft is effectively transmitted to the instrument tip, rather than possibly causing the shaft to roll up outside the endoscopic device. In an embodiment where the reinforcement section is thicker than the distal end portion inside the endoscopic device, the increased thickness may also be used as a stopper to prevent the instrument tip from being overexerted by the endoscopic device. More information about suitable reinforced shafts can be found in co-pending GB application number 2119001.2, the entire contents of which are incorporated herein by reference.

[0055] Alternatively, the key may be a collar that defines a collar channel through which the flexible shaft extends. The collar channel may be concentric with the track channel and, if present, may also be concentric with the clamping channel. Configuring the key as a collar may help provide a stronger attachment around the flexible shaft (e.g., completely around 360 degrees of the flexible shaft), thereby helping to provide a more stable control of the flexible shaft compared to a key that can only be attached to one side of the flexible shaft. Configuring the key as a collar may also advantageously enable a larger outer surface of the key to engage against the elongated track, which in turn may help inhibit / prevent rotational slippage of the key relative to the track.

[0056] In variant embodiments not shown, the key can be configured in different ways as a U-shaped structure that can be attached only along one side (half) of the flexible shaft. In some other embodiments, the attachable portion of the key is between half the circumference and the entire circumference of the shaft, or is less than half the circumference of the shaft. For example, the key can include multiple discrete attachment portions distributed over all or part of the circumference of the shaft.

[0057] As described above, the track and key may have cooperative (e.g., complementary and / or interlocking) cross-sectional shapes that define one or more radial engagement structures (e.g., corners) that are configured to engage with each other to inhibit relative rotation of the track and key. The outer surface of the key may have a polygonal cross-sectional shape that is complementary to the cross-sectional shape of the inner surface of the track channel of the elongated track. In this context, the "outer surface" may refer to the surface that radially faces away from the flexible shaft when in use, while the "inner surface" may refer to the surface that radially faces the flexible shaft when in use. Therefore, the key may have one or more corners on its outer surface that are configured to engage with a corresponding one or more corners of the track channel. This engagement can be used to inhibit relative rotation of the key within the track channel.

[0058] For example, the outer surface of the key (e.g., collar) can have a rhombus ("diamond") or rectangular (e.g., square) cross-sectional shape (as viewed along the axis of the shaft), and the inner surface of the elongated track can have a complementary rhombus or rectangular (e.g., square) cross-sectional shape for inhibiting relative rotation with the key. Such a cross-sectional shape can provide a convenient arrangement for preventing relative rotation while also enabling relative axial movement of the collar within the track. In addition, the square shape helps improve compactness and rotational symmetry. The key can form a snug / tight fit against the track channel of the elongated track to help inhibit relative rotation.

[0059] In alternative embodiments, the key and the elongated track may have other cross-sectional shapes (eg, triangular, hexagonal, octagonal, irregular, elliptical, eccentric, etc.) that inhibit relative rotation between the key and the elongated track.

[0060] Optionally, the track channel terminates in an axial engagement structure for preventing the key from axially moving beyond the track channel. In particular, the track channel may terminate in a narrow section for retaining the key along the track channel. The narrow section may further facilitate adjustment of the torque transfer unit by preventing the elongated track from sliding off the key during axial adjustment. The narrow section and the key may be cooperatively shaped to abut against each other, thereby preventing the key from moving beyond the narrow section. The narrow section may define an opening for conveying the flexible shaft, the opening being smaller than the key, to prevent the key from moving from the track channel.

[0061] Optionally, the track channel may terminate in said narrow section at its proximal and / or distal end to prevent the elongated track from separating from the key in the proximal and / or distal direction. The narrow section may be part of the elongated track itself, or may be part of a different element (e.g., a clamping element) adjacent to the elongated track.

[0062] In contrast to the deformable axial engagement structures discussed with respect to the deformable track embodiments (which are located along the track channel rather than at its ends), the narrow sections at the ends of the track may be sufficiently rigid (non-deformable) to prevent them from moving past the key.

[0063] Preferably, the length of the elongated track is longer than the length of the key. This allows the elongated track to move (e.g., slide) relative to the key (e.g., when the key is attached to the flexible shaft) to adjust the position of the torque transfer unit on the flexible shaft. Optionally, the length of the elongated track is at least three times the length of the key, more preferably at least four times the length of the key, and more preferably at least five times the length of the key. By increasing the ratio of the length of the elongated track to the length of the collar, the torque transfer unit can be adjusted over a larger range of positions on the flexible shaft.

[0064] Optionally, the elongated track includes a first track portion and a second track portion, which can be interconnected to form the elongated track. Providing a two-part track can help facilitate the insertion of a key (e.g., a collar) into the track. This may be particularly convenient, for example in embodiments where the elongated track is a tubular track (having a first tubular track portion and a second tubular track portion) that terminates in a narrow section that would otherwise not be able to receive the key therethrough. The first track portion and the second track portion can be configured to connect in any suitable manner, such as by an interference fit, a snap fit engagement, a threaded engagement, or otherwise.

[0065] Optionally, the first track portion includes an enlarged section for receiving and connecting with the second track portion. The enlarged section can help strengthen the bond between the first track portion and the second track portion by receiving and stabilizing a segment of the second track portion (e.g., the distal segment or the proximal segment). The enlarged section can also serve as an engagement structure to prevent the elongated track from sliding axially relative to the outer cover, as will be further discussed below.

[0066] In embodiments having an outer cover, the elongated track can optionally include an enlarged section (e.g., as part of the first track portion, as discussed above) to define one or more axial engagement structures that are configured to engage the cover (e.g., its corresponding axial engagement structure) to prevent axial movement of the elongated track relative to the cover. For example, the enlarged section can terminate in one or more flanges at its proximal and / or distal ends, which can serve as the axial engagement structure.

[0067] As used herein, the phrase "axial engagement structure" may refer to an engagement structure (e.g., rib, groove, edge, protrusion, notch) formed at a specific axial position (in the proximal / distal direction) of a component (e.g., an elongated track). Thus, a first axial segment (e.g., a proximal end segment) of a component may protrude relative to a second axial segment (e.g., a distal end segment) of the component, which may help inhibit axial movement of the component when engaged with a corresponding structure.

[0068] The axial engagement structure may extend in a radial (angular) direction around the component, while the radial engagement structure may extend in an axial direction along the component.

[0069] Optionally, the elongated track may include a radial engagement structure configured to engage the cover (e.g., its corresponding radial engagement structure) to prevent radial sliding of the elongated track within the cover. The radial engagement structure may be provided, for example, by any corner / bend / adjacent portion along the external cross-sectional shape of the component.

[0070] For example, optionally, at least a portion of the elongated track can include a cross-sectional profile (e.g., a diamond, rectangular, or square cross-sectional shape) configured to engage with an inner surface of the cover to prevent relative rotation. The cross-sectional shape can be defined from a direction along the axis of the flexible shaft. The cross-sectional shape can include one or more corners / bends that serve as radial engagement structures as discussed above.

[0071] The radial engagement structure may extend continuously along the entire length of the elongated track (thereby preventing rotational movement without thereby also preventing axial movement). However, preferably, the radial engagement structure does not extend along the entire elongated track, and therefore terminates in the axial direction, thereby also forming an axial engagement structure that can inhibit axial movement of the component. For example, an enlarged section of the elongated track (as discussed above) may include a radial protrusion, for example as part of its cross-sectional shape, so that the enlarged section may include both axial engagement structure and radial engagement structure.

[0072] Optionally, the present disclosure provides a system or a kit of parts comprising a torque transfer unit described above in conjunction with an interface connector for interconnecting an electrosurgical generator, a fluid supply, and an electrosurgical instrument tip, the interface connector comprising: a housing having an electrical inlet for receiving radio frequency (RF) electromagnetic (EM) energy and / or microwave frequency EM energy from the electrosurgical generator, a fluid inlet for receiving fluid from the fluid supply, and an outlet; and a flexible shaft, wherein the flexible shaft is configured to connect the outlet to the instrument tip, the flexible shaft having a coaxial line connected to the electrical inlet and a fluid channel in fluid communication with the fluid inlet. For example, the interface connector can be an interface connector as described in GB 2 523 246.

[0073] The present invention includes combinations of the described aspects and preferred features except where such combinations are expressly not permitted or are expressly avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Example embodiments illustrating the principles of the present invention will now be discussed with reference to the accompanying drawings, wherein like reference numerals refer to like elements.

[0075] Figure 1 is a schematic diagram of a complete electrosurgical system to which the present invention may be applied;

[0076] Figure 2 is a perspective cutaway view of a torque transfer unit as an embodiment of the present invention (with the key shown in its entirety rather than in cutaway);

[0077] FIG. 3A to FIG. 3C yes Figure 2 a side cross-sectional view of the torque transfer unit shown with the key shown at different locations within the elongated track;

[0078] Figure 4 yes Figure 2 An exploded side view of the torque transfer unit is shown;

[0079] Figure 5 yes Figure 2 A perspective view of a torque transfer unit shown connected to a flexible shaft external to an endoscopic surgical device;

[0080] Figure 6 Is suitable for Figure 2 A perspective view of a modified actuating element for use with the torque transfer unit shown;

[0081] Fig. 7A and Figure 7B are a side view and an exploded view, respectively, of an alternative torque transfer unit as an embodiment of the present invention;

[0082] Figure 8 is a side view of a modified torque transmission unit having a torsion spring collet-type clamping element;

[0083] Fig. 9 Is suitable for Figure 8 A perspective view of a torsion spring in a torque transfer unit;

[0084] Fig. 10A and Fig. 10B are side and perspective views, respectively, of an alternative torque transmission unit having a torsion spring collet-type clamping element with a single operating lever;

[0085] Fig.11 is a perspective view of an embodiment torque transmission unit with an articulated clamping element;

[0086] Fig.12 yes Fig.11 A perspective view of the hinge clamping element shown;

[0087] Fig.13 is a side view showing a modified hinge clamping element;

[0088] Fig.14 is a side view of an embodiment torque transfer unit having a graspable member that is deformable to adjust the position of the torque transfer unit relative to the critical portion;

[0089] Fig.15 yes Fig.14 A perspective view of a torque transfer unit of FIG. 1 , wherein no key or flexible shaft is shown; and

[0090] Fig.16 Is suitable for Fig.14 A side view of a variant track and key configuration of a torque transfer unit. DETAILED DESCRIPTION

[0091] Various aspects and embodiments of the present invention will now be discussed with reference to the accompanying drawings. Additional aspects and embodiments will be apparent to those skilled in the art. All documents mentioned herein are incorporated herein by reference.

[0092] Figure 1 1 is a schematic diagram of a complete electrosurgical system 100 capable of selectively supplying any or all of RF energy, microwave energy, and fluid (e.g., saline or hyaluronic acid) to the distal end of an invasive electrosurgical instrument. The system 100 includes a generator 102 for controllably supplying electromagnetic (EM) energy. In this embodiment, the EM energy includes RF EM energy and / or microwave frequency EM energy. A generator suitable for this purpose is described in WO 2012 / 076844, which is incorporated herein by reference.

[0093] The generator 102 is connected to an interface connector 106 via an interface line 104. The interface connector 106 is also connected to receive a supply of pressurized fluid from a fluid delivery device 108 via a fluid supply line 107. The function of the interface connector 106 is to combine the inputs from the generator 102 and the fluid delivery device 108 into a single flexible shaft 112 that extends from the distal end of the interface connector 106. It should be understood that the shaft 112 may form a part of the interface connector 106.

[0094] The flexible shaft 112 may be inserted through the entire length of an instrument (working) channel of an endoscopic surgical device 114. A torque transfer unit 116 may be mounted on the proximal length of the shaft 112 between the interface connector 106 and the endoscopic surgical device 114. The torque transfer unit 116 engages the shaft to permit the shaft to rotate within the instrument channel of the endoscopic surgical device 114. The configuration of the torque transfer unit 116 is discussed in more detail below.

[0095] Flexible shaft 112 has an electrosurgical instrument tip 118, which is molded into an instrument channel that passes through a surgical endoscopic device 114 (e.g., an endoscope), and protrudes at the far end of the instrument channel (e.g., into the patient's body). The instrument tip includes an action tip for delivering RF EM energy and / or microwave EM energy to biological tissue, and a hole for delivering a pressurized fluid (e.g., saline, Gelofusine, and / or hyaluronic acid to which a marker dye has been added). These combined technologies provide unique solutions for cutting and destroying unwanted tissue, as well as the ability to seal blood vessels around the target area. By applying pressure to the fluid, the surgeon can inject the fluid between the tissue layers to expand and mark the position of the lesion to be treated. Injecting fluid in this way will lift and separate the tissue layers, thereby making it easier to excise around the lesion and easier to plane through the submucosal layer, thereby reducing the risk of intestinal wall perforation and unnecessary thermal damage to the muscle layer.

[0096] The instrument tip 118 also includes a protective shell positioned beneath the active tip to assist in the tissue planing action and also to help prevent accidental perforations and ensure the viability of the remaining tissue, thereby promoting more rapid healing and post-operative recovery.

[0097] The structure of the instrument tip 118 can be specifically designed for use with a conventional steerable flexible endoscope having a working channel with an inner diameter of at least 2.2 mm and a working length of between 60 cm and 170 cm. In this way, most smaller diameter instruments are contained within the lumen of a larger, primarily polymeric insulating device (i.e., the flexible endoscope channel). In practice, the distal assembly protrudes only 5 mm to 25 mm from the distal end of the endoscope channel so as not to block the field of view or adversely affect camera focus. The protruding portion of the distal assembly is the only portion of the instrument that comes into direct contact with the patient.

[0098] At the proximal end of the endoscope working channel, which is typically held 50 to 80 cm from the patient, a flexible shaft 112 emerges from the working channel port and extends a further 30 to 100 cm to the interface connector 106. When in use, the interface connector 106 is typically held by a gloved assistant during the entire procedure. The interface line 104 is connected to the generator 102 using a QMA-type coaxial interface that is designed to allow continuous clockwise or counterclockwise rotation. This permits the interface connector 106 to rotate with the torque transfer unit 116 under the control of the user. The assistant supports the interface connector 106 throughout the procedure to assist the user in sympathetic instrument rotation and fluid injection.

[0099] Figure 2 3 to 4 are perspective cross-sectional views showing a torque transfer unit 116 according to one embodiment of the present invention. Figure 5 Further details of the torque transfer unit 116 are shown.

[0100] The torque transfer unit 116 has an elongated track 120, a key 122, a clamping element 124, and a cover 126. (For illustrative purposes, it should be noted that Figure 2 All elements of the torque transfer unit 116 are shown in cross-section, except for the key 122 which is shown in its entirety.

[0101] In this embodiment, the key 122 is configured as a collar that is arranged to surround a flexible shaft (e.g., Figure 1 The key 122 is assembled around the circumference of the shaft 112). Therefore, the key 122 defines a key channel 128 (also referred to as a collar channel) for receiving the flexible shaft therethrough. The key channel 128 has a circular cross-section and is configured to form a tight fit (e.g., an interference fit) around the flexible shaft.

[0102] The key 122 has a polygonal (e.g., square, rhombus, rectangular) cross-sectional shape on its outer surface (as viewed along the longitudinal axis of the flexible shaft), which forms a plurality of (e.g., four) radial engagement structures in the form of outer corners. In this embodiment, the key 122 is fully assembled within the elongated track 120, which is a tubular track that defines a track channel 130 that is axially movable relative to the key 122. On its inner surface, the elongated track 120 (i.e., the track channel 130) has a polygonal (e.g., square, rhombus, rectangular) cross-sectional shape that is complementary to the outer cross-sectional shape of the key 122. Therefore, the elongated track 120 has a plurality of (e.g., four) radial engagement structures in the form of inner corners, which are configured to align and engage with the radial engagement structures provided by the four outer corners of the key 122. The engagement of these corners prevents the key 122 from sliding radially within the track channel 130.

[0103] The elongated track 120 is formed by a first track portion 132 and a second track portion 134, which are configured to cooperate to form a track channel. The elongated track 120 terminates at its distal and proximal ends with a distal narrow section 136a and a proximal narrow section 136b, which are sized to retain the key 122 within the track channel 130. Therefore, during manufacturing, the key 122 is first inserted into the first track portion 132 or the second track portion 134, and then the first track portion 132 and the second track portion 134 are connected to retain the key 122 within the track channel 130.

[0104] In this embodiment, the first track portion 132 includes an enlarged section 138 for receiving the second track portion 134 therein. When connected, the second track portion 134 forms a tight fit (e.g., an interference fit) within the enlarged section 138, thereby forming a track channel 130 passing through both the first track portion 132 and the second track portion 134.

[0105] The key 122 and the elongated track 120 do not form a tight interference fit. Instead, these elements are sized and shaped to allow relative axial movement when the key 122 is located within the track channel 130, thereby enabling adjustment of the position of the torque transfer unit 116 on the flexible shaft. Thus, the length of the elongated track 120 (and in particular the track channel 130 thereof) is greater than the length of the key 122 (e.g., at least three times the length of the key 122). The length of the track channel relative to the key 122 effectively defines the range of positions to which the torque transfer unit 116 can be moved.

[0106] A clamping element 124 is located at the proximal end of the interface joint 116 and is actuatable between a clamped position for clamping onto the flexible shaft to prevent axial movement of the elongated track 120 relative to a key 122 (which may be attached to the flexible shaft when in use) and a loosened position for loosening the flexible shaft to allow axial movement of the elongated track 120 relative to the key 122. Thus, the axial position of the torque transfer unit 116 can be adjusted by loosening the clamping element 124 and moving the elongated track to a different axial position relative to the key 122.

[0107] FIG. 3A to FIG. 3C An example position of the elongated track 120 relative to the key 122 is shown. In use, the key 122 can remain attached to the flexible shaft and therefore not be repositioned on the shaft during adjustment of the torque transfer unit 116. Instead, the key 122 can remain fixed while the rest of the torque transfer unit 116 moves about it. Once the torque transfer unit 116 is in the desired position, the clamping element 124 can be actuated to the clamping position to hold the torque transfer unit 116 in place.

[0108] In this embodiment, the clamping element 124 is rotatably actuated. The clamping element 124 includes a clamp head 140 and an actuating element 142 (eg, Figure 4 1 and 2. The elongated rail 120 is best shown in the drawings. A clamping element 124 is attached to the proximal end of the elongated rail 120. The collet 140 defines a clamping channel through which the flexible shaft extends. An actuation element 142 is rotatably actuated (e.g., by a user's thumb / finger) between a clamped position and an unclamped position to selectively tighten the channel of the collet 140 to the flexible shaft.

[0109] The cover 126 is arranged around the elongated track 120 to improve ergonomics and ease of use. The cover 126 can be formed of a deformable / flexible material (e.g., silicone). In this embodiment, the cover 126 includes a gripping surface in the form of a plurality of notches / grooves that are sized and shaped to be gripped by the user's thumb / fingers.

[0110] The elongated track 120 has axial and radial engagement structures on its outer surface, which are configured to engage against the cover 126 to prevent radial and / or axial sliding relative to it. In this embodiment, the elongated track 120 has an outer surface with a polygonal (e.g., square, diamond, rectangular) cross-sectional shape that provides a radial engagement structure (e.g., four corners), and the radial engagement structure is configured to engage against the inner surface of the cover 126 to prevent radial sliding. In addition, the expanded section 138 of the first track portion 132 forms an axial engagement structure 144a-b in the form of a protrusion / flange at each end (distal and proximal ends) of the expanded section 138. The inner surface of the cover 126 is configured to fit closely with the outer shape of the elongated track 120, thereby resisting relative movement across the radial and axial engagement structures, thereby preventing the cover 126 from sliding radially and axially relative to the track 120.

[0111] Figure 5 A torque transfer unit 116 is shown positioned on the flexible shaft 112 external to the surgical endoscopic device 114. Figure 5As shown by the arrow in , the clamping element 124 (and in particular the actuating element 142) can be rotated about the longitudinal axis to actuate from the loose position to the clamping position. It may be advantageous to position the torque transfer unit 116 as close to the endoscopic device 114 as possible in order to provide optimal control of the instrument tip at the distal end of the endoscopic device. However, since the key 122 is preferably fixed to the flexible shaft 112, the adjustable position of the torque transfer unit 116 is limited by the fixed position of the key 122 on the flexible shaft 112. Therefore, in order to enable use with a variety of surgical endoscopic devices 114 (each of which may have a different length), it may be desirable to provide a parts kit having a plurality of flexible shafts 112, each of which is connected to a corresponding key 122 of the torque transfer unit 116 at a different position along the flexible shaft 112. This can help provide a kit that is best suited for use with a variety of surgical endoscopic devices having different lengths, because a shaft having a key attached thereto can be selected, the position of the key closely corresponding to the length of the desired endoscopic device 114.

[0112] Figure 6 Shows the suitability with Figures 1 to 5 A perspective view of a plurality of variant actuation elements for use with the illustrated torque transfer unit 116. The variant actuation elements are similar to the actuation element 142, but illustrate various different gripping surfaces, for example, wherein each actuation element has a plurality of notches, ribs, or wings that are radially distributed around the actuation element and extend axially along the actuation element, or wherein similar actuation elements do not include a gripping surface at all.

[0113] Fig. 7A and Figure 7B 1 and 2 show a side view and exploded view of an alternative torque transfer unit as an embodiment of the present invention. The torque transfer unit 146 is similar to Figures 2 to 5 The torque transfer unit 146 is similar to the torque transfer unit 116 of FIG. 1 and includes like reference numerals to indicate like elements. However, the torque transfer unit 146 differs in the following respects.

[0114] The key 148 of the torque transfer unit 146 has a different shape than the key 122 of the torque transfer unit 116. Specifically, while the key 122 has a rectangular (e.g., square) cross-sectional profile along its entire axial length, the cross-sectional shape of the key 148 changes along its axial length from a rectangular (e.g., square) cross-section to a circular cross-section.

[0115] Furthermore, the torque transfer unit 146 has a first snap-fit ​​feature 150A on the first track portion 132 (particularly the enlarged section 138 thereof) and a complementary second snap-fit ​​feature 150B on the second track portion 134. The first snap-fit ​​feature 150A and the second snap-fit ​​feature 150B are configured to engage with each other to facilitate interconnection of the first track portion 132 and the second track portion 134 to form an elongated track.

[0116] Figure 8 A side view of a torque transmission unit 150 according to another embodiment of the invention is shown. In contrast to the threaded clamping element shown in the previous embodiments, the torque transmission unit 150 has a clamping element which comprises a torsion spring 152 . Fig. 9 An example of a suitable torsion spring 152 is shown. The torsion spring 152 includes an annular portion that defines a clamping channel 154 through which the flexible shaft 112 extends. The torsion spring 152 also includes two radial projections, each of which includes a handle or grip 156 and forms a terminal end of the spring. These portions can be squeezed together to increase the size of the clamping channel 154, thereby selectively loosening the flexible shaft 112.

[0117] Fig. 10A and Fig. 10B A perspective view and a side view, respectively, of an alternative torque transfer unit 158 ​​incorporating a Figures 8 to 9 The torsion spring 152 is similar to the torsion spring 152, but the difference is that the torque transfer unit 158 ​​replaces the pair of handles 156 with an actuating element in the form of a single joystick 160. In use, the joystick 160 can be actuated (rotated) about the axis of the shaft by the user's thumb, such as Fig. 10A This movement causes the spring 152 to expand, thereby opening the clamping channel 154 to release the flexible shaft 112 and allow axial adjustment of the torque transfer unit.

[0118] Fig.11 1 shows a perspective view of a torque transmission unit 162 according to another embodiment of the present invention. The torque transmission unit 162 includes an articulated clamping element 164, such as Fig.12 As shown. The articulated clamping element 164 is a single unitary member (e.g., formed of plastic). The clamping element 164 includes a first jaw 166 and a second jaw 168, which together form an integral U-shaped structure. The first jaw 166 is configured to pivot toward or away from the second jaw 168, for example, because the first jaw 166 is relatively flexible (e.g., due to its material and / or shape). The connection between the first jaw 166 and the second jaw 168 includes a hole for conveying a flexible shaft therethrough.

[0119] The torque transfer unit includes a cover 170, which is similar to the cover 126 of the previous embodiment, but differs in that the cover 170 includes a cutout for accommodating the pivotal movement of the first jaw 166. The articulated clamping element 164 is retained within the cover 170, wherein the jaws 166, 168 are open toward the proximal end of the cover 170. In this embodiment, the inner surface of the cover 170 defines the track channel 130, that is, the cover 170 is integral with the elongated track. The torque transfer unit 162 also includes a key (not shown) that is axially movable within the track channel 130 and rotationally fixed relative to the track channel 130, in a manner similar to the previous embodiment.

[0120] The clamping element 162 also includes a retaining member 172 that extends from the proximal end of the second jaw 168 toward the proximal end of the second jaw 166, spanning the open end of the U-shaped structure. The retaining member 172 includes a hole for receiving a flexible shaft therethrough. The retaining member 172 is integral with the first jaw 166 and the second jaw 168. The retaining member 172 is flexible so that it can be actuated (pivoted) by the user to bend the retaining member 172 (at the proximal end) away from the jaws 166 and 168. Once released by the user, the retaining member 172 is configured to elastically rebound to its initial upright position (i.e., Fig.11 and Fig.12 168). A first end of the retaining member 172 (proximal to the first jaw 166) includes a hook 174 for engaging a free (proximal) end 176 of the first jaw 166 when the first jaw 166 is pushed (pivoted) toward the second jaw 168.

[0121] In use, in order to move from the released position (such as Fig.11 and Fig.12 174) to a clamped position (not shown), the user can bend the retaining member 172 proximally so that it pivots relative to the second jaw 168. This movement is facilitated by the location of the retaining member 172 at the proximal end of the torque transfer unit 162, thereby providing intuitive and simple adjustment. When the retaining member 172 is bend proximally, the user can push the first jaw 166 toward the second jaw 168 so that the free end 176 of the first jaw 166 slides over the hook 174. The user can then release the retaining member 172, thereby allowing the retaining member to 'spring back' and hold the first jaw 166 in place due to the engagement of the hook 174 against the free end 176.

[0122] In this embodiment, the first jaw 166 and the second jaw 168 each include one or more protrusions (or teeth) 178A-C, which are configured to abut against the flexible shaft when the clamping element 162 is in the clamping position. The second jaw 168 includes a proximal tooth 178A and a distal tooth 178C, and the first jaw 166 includes an intermediate tooth 178B axially located between the proximal tooth 178A and the distal tooth 178C. Each tooth 178A-C has a curved inner profile shape to engage against the circumference of the flexible shaft. In the clamping position, the teeth 178A-C help clamp the flexible shaft between the jaws 166 and 168. Both jaws also include elongated teeth or protrusions 178D, E extending along their distal ends to facilitate grasping the flexible shaft.

[0123] Fig.13 Is suitable for Fig.11 162. The torque transfer unit 162 of the embodiment of the present invention is used in conjunction with the torque transfer unit 162 of the embodiment of the present invention. The clamping element 180A differs from the remaining clamping elements primarily in the shape and configuration of the teeth. Specifically, the clamping element 180A includes a plurality of teeth on the first jaw 166 and no teeth on the second jaw 168. The clamping elements 180B-G differ primarily in their shape and thickness, which can be modified to affect their flexibility.

[0124] Fig.13 Also shown are two variant clamping elements 180H-I suitable for use with a modified torque transfer unit (not shown). These clamping elements 180H-I differ from the previously described clamping elements 180A-G in that the clamping elements 180H-I are integral with an elongated track 182H-I, thereby defining a keyed track channel.

[0125] exist Fig.13 In FIG. 1 , clamping elements 180A, 180C, 180E, 180H, and 180I are shown in a clamped position, while the other elements are shown in a released position.

[0126] Fig.14 1 is a side view of a torque transfer unit 182 according to another embodiment. The torque transfer unit 182 includes similar reference numerals to the previous torque transfer unit to indicate similar elements. However, the torque transfer unit 182 differs from the previous embodiments in that the torque transfer unit 182 does not include a different clamping unit. Instead, the torque transfer unit 182 includes a graspable member 184 (similar to the cover 126 or 170) that also provides the function of an elongated track. The graspable member 184 is formed on its inner surface to define a track channel 186 and is configured on its outer surface to provide a gripping surface.

[0127] Similar to the previous embodiment, the torque transfer unit includes a key 188 that can be attached to the flexible shaft 112 and can move along the track channel 186. The key 188 and the elongated track (i.e., the grippable member 184) are configured to engage with each other to inhibit relative rotation of the key and the track channel 186. Fig.15 , which shows that the track channel 186 has a square cross-sectional shape when viewed along the axis of the channel (i.e., from the proximal or distal end of the device). When viewed from this direction, the key 188 also has a square cross-sectional shape and is sized to inhibit (e.g., prevent) relative rotation with the track channel.

[0128] Compared to the previous embodiments, the size of the track channel varies along its length. Specifically, the track channel 186 has a wavy (scalloped) profile, provides multiple axial engagement structures (e.g., corners) that are configured to maintain the axial position of the key and define multiple discrete positions where the key 188 can be positioned. The key 188 has a complementary circular profile (when viewed from the side of the device) to facilitate axial positioning relative to the sectored track.

[0129] In use, to adjust the axial position of the key relative to the track channel, the graspable member 184 can be pulled or pushed relative to the shaft 112. Because the graspable member 184 (and in particular the axial engagement structure) is deformable, it can be moved past the key 188 if the user applies sufficient force. Therefore, the user can actuate the torque transfer unit by applying sufficient force on the graspable member 184 to deform and move it. Once in the desired position, the user can release the graspable member, which will retain the key in the desired axial position by means of the axial protrusion.

[0130] Fig.16 It is shown that it is applicable to Fig.14 and Fig.15 1 and 1 . A side view of a modified track channel 190 and key 192 of a torque transfer unit 184 of FIG. 1 . Track channel 190 differs from track channel 186 in that track channel 190 has a sawtooth profile rather than a scalloped profile (extending axially along the track channel). Accordingly, key 192 has a recessed side profile that is configured to receive one of the protrusions of the sawtooth track channel. When viewed in the axial direction (i.e., from the proximal or distal end of the torque transfer unit), key 192 and track channel 190 may have a square cross-sectional shape, similar to Figure 14 to Figure 15 , or may have any other shape (e.g., any non-circular shape) configured to inhibit relative rotation.

[0131] The features disclosed in the foregoing description or in the appended claims or in the drawings, expressed in their specific form or as means for performing the disclosed functions or as methods or processes for obtaining the disclosed results, may, where appropriate, be used alone or in any combination of such features to realize the invention in its various forms.

[0132] Although the present invention has been described in conjunction with the exemplary embodiments described above, many equivalent modifications and variations will be apparent to those skilled in the art when this disclosure is given. Therefore, the exemplary embodiments of the present invention set forth above are considered to be illustrative rather than restrictive. Various changes may be made to the described embodiments without departing from the spirit and scope of the present invention.

[0133] For the avoidance of any doubt, any theoretical explanations provided herein are provided to enhance the reader's understanding. The inventors do not wish to be bound by any of these theoretical explanations.

[0134] Any section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described.

[0135] Throughout the specification, including the appended claims, unless the context requires otherwise, the words "comprise" and "include" and variations such as "comprises", "comprising" and "including", will be understood to imply the inclusion of stated integers or steps or groups of integers or steps but not the exclusion of any other integers or steps or groups of integers or steps.

[0136] It must be noted that, as used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly indicates otherwise. Ranges may be expressed herein as from "about" one particular value and / or to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, when a value is expressed as an approximation by using the antecedent "about", it is understood that the particular value forms another embodiment. The term "about" with respect to a numerical value is optional and means, for example, + / - 10%.

[0137] Reference Number

[0138] 100 Electrosurgery System

[0139] 102 Generator

[0140] 104 interface pipeline

[0141] 106 interface connector

[0142] 108 Fluid delivery device

[0143] Electrosurgical instruments

[0144] 112 Flexible shaft

[0145] 118 Instrument Tip

[0146] 107 Fluid supply line

[0147] 114Surgical Endoscopy Devices

[0148] 116,146,150,158,162,182 Torque transfer unit

[0149] 120 Slim Track

[0150] 130 track channels

[0151] 136a-b Stenosis

[0152] 132 First track section

[0153] 138 expansion section

[0154] 144a-b axial joint structure

[0155] 134 Second track section

[0156] 122, 148, 188, 192 keys (e.g., collar)

[0157] 128 loop channels

[0158] 124 Clamping element (chuck)

[0159] 140 thread chuck

[0160] 142 driving element

[0161] 152 Torsion spring

[0162] 154 clamping channel

[0163] 156 handle

[0164] 160 Joystick

[0165] 164,180AI clamping element (hinge)

[0166] 166 First jaw

[0167] 176 Free end

[0168] 178B middle teeth / protrusions

[0169] 178E Slender teeth / protrusions

[0170] 168 Second jaw

[0171] 178A proximal teeth / protrusions

[0172] 178C Distal Teeth / Protrusions

[0173] 178D Slender teeth / protrusions

[0174] 172Retaining member

[0175] 174 hook

[0176] 126,170,184 Cover / grip member

[0177] 186,190 track channels

Claims

1. A torque transmission unit for a rotating flexible shaft, the torque transmission unit comprising: an elongated track defining a track channel; as well as a key attachable to the flexible shaft and movable along the track channel, the key and the elongated track configured to engage one another to inhibit relative rotation of the key and the track channel; The torque transfer unit is actuatable to selectively adjust an axial position of the key relative to the track channel.

2. The torque transfer unit of claim 1 further comprising a clamping element connectable to the elongated track and actuatable to selectively adjust the axial position of the key relative to the track channel, the clamping element actuatable between: a clamping location for clamping onto the flexible shaft to prevent axial movement of the elongated track relative to the key; and A released position is provided for releasing the flexible shaft to allow axial movement of the elongated track relative to the key.

3. The torque transfer unit of claim 2, wherein the clamping element has a gripping surface to facilitate gripping by a user.

4. A torque transfer unit as claimed in claim 2 or claim 3, wherein the clamping element is rotatably actuatable between the clamping position and the release position.

5. The torque transfer unit of any one of claims 2 to 4, wherein the clamping element defines a clamping channel through which the flexible shaft extends, wherein the clamping element is actuatable to selectively secure the clamping channel to the flexible shaft.

6. The torque transfer unit of claim 5, wherein the clamping element is a collet-type clamp.

7. A torque transfer unit as claimed in any one of claims 2 to 6, wherein the clamping element comprises a resilient member resiliently biased towards the clamping position.

8. The torque transfer unit of claim 5, wherein the clamping element comprises: a first jaw and a second jaw, the first jaw being movable relative to the second jaw to secure the clamping channel to the flexible shaft; as well as A retaining member is actuatable to retain the first jaw in the clamped position or to release the first jaw from the clamped position.

9. A torque transfer unit as claimed in any preceding claim, further comprising an outer cover surrounding the elongate track, the cover including a gripping surface to facilitate gripping by a user.

10. The torque transfer unit of claim 9, wherein the outer surface of the elongated track and the inner surface of the cover are configured to engage one another to inhibit rotation and / or axial movement of the elongated track relative to the cover.

11. A torque transfer unit as claimed in any preceding claim, comprising axial engagement formations along the track channel; and The elongated track is elastically deformable between a non-deformed state in which the axial engagement structure inhibits relative movement of the elongated track past the key and a deformed state in which the elongated track is able to slide past the key.

12. A torque transfer unit as claimed in any preceding claim, wherein the key is a collar defining a collar channel through which the flexible shaft extends.

13. A torque transfer unit as claimed in any preceding claim, wherein an outer surface of the key has a rectangular cross-sectional shape and an inner surface of the elongate track has a complementary rectangular cross-sectional shape for inhibiting relative rotation with the key.

14. A torque transfer unit as claimed in any preceding claim, wherein the track channel terminates in a narrow section for retaining the key along the track channel.

15. A torque conversion unit as claimed in any preceding claim, wherein the length of the elongate track is at least three times the length of the key, more preferably at least four times the length of the key, more preferably at least five times the length of the key.

16. A torque transfer unit as claimed in any preceding claim, wherein the elongated track comprises a first track portion and a second track portion, the first track portion and the second track portion being connectable to each other to form the elongated track.

17. The torque transfer unit of claim 16, wherein the first track portion includes an enlarged section for receiving and connecting with the second track portion.

18. A parts kit, comprising: A torque transfer unit as claimed in any preceding claim; as well as An interface connector for interconnecting an electrosurgical generator, a fluid supply, and an electrosurgical instrument tip, the interface connector comprising: A housing, the housing comprising: an electrical inlet for receiving radio frequency (RF) electromagnetic (EM) energy and / or microwave frequency EM energy from the electrosurgical generator; a fluid inlet for receiving fluid from the fluid supply; and Export; and a flexible shaft, wherein the flexible shaft is configured to connect the outlet to the instrument tip, the flexible shaft having: a coaxial line connected to the electrical inlet; and A fluid passageway is in fluid communication with the fluid inlet.

Images