Patent Description:
This disclosure relates to minimally invasive (e.g., endoscopic and/or laparoscopic) medical devices and related methods of use. In embodiments, the disclosure relates to one or more locking mechanisms for end effectors, e.g., tissue fastening devices such as stapler devices, and related methods of use, among other aspects.

Technological developments have given users of medical systems, devices, and methods, the ability to conduct increasingly complex procedures on patients. The grasping and/or coupling of tissue in a patient's body, for example, may be performed by surgical devices that grasp or clamp tissue between opposing jaw structures and then fasten or cut the tissue. Systems of the above type are for example disclosed in <CIT>, <CIT> and <CIT>. A drawback of these systems may include, for example, maintaining a desired orientation of the jaws of an end effector during a procedure, such as a stapling procedure, a cutting procedure, and/or additional medical procedures. For example, to access tissue, an end effector may be articulated about a pivot point. During a cutting or a fastening step, actuation of the cutting and/or fastening device may cause the end effector to pivot from the selected orientation to a different, undesired orientation. Thus, tissue may not be properly stapled and/or cut, which may increase therapy time and/or cost, may cause undesired or incomplete fastening of tissues, and/or may require additional therapy/intervention at the target site. This disclosure may solve one or more of these problems or other problems in the art. The scope of the disclosure, however, is defined by the attached claims and not the ability to solve a specific problem.

According to an aspect, a medical device includes an end effector at a distal end of the medical device, an actuator coupled to a proximal end of the end effector, a pivot arm pivotally coupled to the end effector distal of the proximal end of the end effector, where actuation of the actuator pivots the end effector relative to the pivot arm, and a lock on the end effector and the pivot arm, where the lock has a first state permitting the end effector to pivot relative to the pivot arm and a second state restricting the end effector from pivoting relative to the pivot arm.

The end effector may include a first jaw, and a second jaw hingedly connected to the first jaw and configured to move between an open position and a closed position.

The locking mechanism may include a plurality of teeth at a distal end of the pivot arm, wherein the plurality of teeth may define a plurality of spaces, and a tab connected to the end effector, wherein the tab may be configured to engage a space from the plurality of spaces in the second state.

The lock is in the first state when the pair of jaws is in the open position, and the lock is in the second state when the pair of jaws is in the closed position.

The end effector may be configured to pivot independently of a movement of the first jaw relative to the second jaw.

The locking mechanism may include a sprocket connected to the pivot arm, wherein the sprocket may include a plurality of teeth defining a plurality of spaces, and a pawl pivotally connected at the proximal end of the end effector and may be configured to engage the plurality of spaces.

The medical device may further comprise a wire connected to the pawl and extending in a proximal direction, wherein the pawl may be biased into engagement with the plurality of spaces of the sprocket, and wherein moving the wire in the proximal direction may be configured to pivot the pawl away from the sprocket to disengage the pawl from the plurality of spaces.

The sprocket may be arc shaped, and wherein a convex arrangement of the plurality of spaces of the sprocket may face proximally.

The locking mechanism may include a ball-nose spring plunger.

The ball-nose spring plunger may include a spring coupled at a first end of the end effector, wherein the spring may be configured to extend from the first end and compress along a compression axis, a plurality of detents fixed to the pivot arm, and a ball bearing connected to the spring and selectively engaging each of the plurality of detents, wherein the ball bearing may be configured to move along the compression axis.

The ball bearing may be configured to move from a first detent of the plurality of detents to an adjacent, second detent of the plurality of detents as the end effector pivots about the pivot arm, and wherein the spring may be configured to be compressed from a first position to a second position and expand back to the first position as the ball bearing moves from the first detent to the second detent.

The medical device may further comprise an actuation wire fixed to a proximal end of the end effector, wherein actuation of the actuation wire may be configured to move the end effector between an open position and a closed position.

The pivot arm may include a first opening at a proximal end of the pivot arm, a second opening in a sidewall of the pivot arm, and a lumen extending from the first opening to the second opening. The actuator may be configured to extend through each of the first opening, the lumen, and the second opening.

The medical device may further comprise a handle assembly configured to actuate the end effector and the locking mechanism, wherein a proximal end of the actuator may be connected to a distal end of the handle assembly, and a catheter may include at least one lumen and may extend distally from the handle assembly, wherein the actuator may extend through the at least one lumen, and wherein the pivot arm may be fixed to a distal end of the catheter.

A pivot angle may be defined between a longitudinal axis of the end effector and a longitudinal axis of the pivot arm, wherein a distal movement of the actuator may be configured to increase the pivot angle, and wherein a proximal movement of the actuator may be configured to decrease the pivot angle.

According to another aspect, a medical device comprises an elongated member, an end effector connected to a distal end of the elongated member, wherein the end effector may include a tab, and a catheter including a plurality of spaces at a distal end, wherein the tab may be configured to selectively engage the plurality of spaces to inhibit pivotal movement of the end effector.

The elongated member may extend through an opening of the catheter proximally of a distal end of the catheter, and wherein the end effector may be pivotally coupled to the catheter distally of the opening.

According to another aspect, a medical method includes advancing an end effector and a pivot arm to a target site within a patient, pivoting the end effector relative to the pivot arm about a pivot axis until a desired orientation of the end effector is achieved, locking the orientation of the end effector relative to the pivot arm, and performing an operation via the end effector.

The end effector may include a first jaw, and a second jaw hingedly connected to the first jaw, wherein the end effector may include an open configuration and a closed configuration, and wherein a distance between distal ends of the first jaw and the second jaw may be greater in the open configuration than a distance between the distal ends of the first jaw and the second jaw in the closed configuration.

When the end effector is in the closed configuration, the end effector may be locked relative to the pivot arm, and when the end effector is in the open configuration, the end effector may be unlocked relative to the pivot arm.

This disclosure is described with reference to exemplary medical systems and medical tools for accessing a target site, for example, for grasping, cutting, and/or stapling tissue. This may provide improved medical tool functionality and/or may assist medical professionals to improve cutting and/or fastening of tissue. However, it should be noted that reference to any particular device and/or any particular procedure is provided only for convenience and not intended to limit the disclosure. A person of ordinary skill in the art would recognize that the concepts underlying the disclosed devices and application methods may be utilized in any suitable procedure, medical or otherwise. This disclosure may be understood with reference to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals.

For ease of description, portions of the disclosed devices and/or their components are referred to as proximal and distal portions. It should be noted that the term "proximal" is intended to refer to portions closer to a user of the devices, and the term "distal" is used herein to refer to portions further away from the user. Similarly, "extends distally" indicates that a component extends in a distal direction, and "extends proximally" indicates that a component extends in a proximal direction. Further, as used herein, the terms "about," "approximately," and "substantially" indicate a range of values within +/- <NUM>% of a stated or implied value. Additionally, terms that indicate the geometric shape of a component/surface refer to exact and approximate shapes.

Embodiments of this disclosure may be used to cut and/or fasten tissue in an endo-luminal space, or facilitate the process thereof. According to an example, the fastening device may be a tissue stapling apparatus, which may include a resection or cutting mechanism (e.g., an integrated knife) and a stapling mechanism (e.g., a stapler). The fastening device may be delivered through an endoscope working channel to the target tissue site. All or parts of the fastening device could be metallic (such as stainless steel, titanium, or cobalt chrome), plastic (such as polyetheretherketone (PEEK) or the like), or include a shape memory metal (such as nitinol), a shape memory polymer, a polymer, or any combination of materials. While reference is made herein to a fastening device, the described locking members may be used with any device pivotally connected to a distal end of a catheter, sheath, tube, or the like. The locking members may prevent pivotal movement of an end effector or other device pivotally connected to the distal end of, e.g., the catheter. This may improve an operation of the end effector. For example, preventing a pivotal rotation of a stapler during stapling may improve the connection between the adjacent tissues.

<FIG> shows an apparatus <NUM> in accordance with an example of this disclosure. Apparatus <NUM> may be a surgical stapling apparatus configured to engage body tissue, and apply a plurality of fasteners thereto during minimally invasive procedures, such as laparoscopic or endoscopic procedures. In some embodiments apparatus <NUM> may be a suturing apparatus to delivering a suture for tissue closure during minimally invasive surgical procedures. Apparatus <NUM> may be used to apply a suture, clips, or other fasteners, but will be primarily discussed in the context of grasping tissue in preparation of performing additional procedures to the tissue, e.g., stapling and/or cutting the tissue.

As illustrated in <FIG>, apparatus <NUM> includes a handle assembly <NUM> at a proximal end, an end effector <NUM> at a distal end, and an elongated body <NUM> (e.g., a catheter or the like) connecting a distal end of handle assembly <NUM> to a proximal end of end effector <NUM> (as will be explained herein, end effector <NUM> may include a stapler device <NUM>). Elongated body <NUM> may extend any length suitable for endoscopic or laparoscopic procedures, and may be configured to be positioned within a working channel of an endoscope. Alternatively, elongated body <NUM> may extend along an outer surface of the endoscope if, for example, the endoscope includes only a single lumen and/or a diameter of the lumen(s) of the endoscope are too small to receive elongated body <NUM>. Elongated body <NUM> may be detachable from handle assembly <NUM> to facilitate insertion of elongated body <NUM> into a working channel of an endoscope or a channel of another device, for example by backloading elongated body <NUM> into the working channel. In some examples, elongated body <NUM> may be flexible, steerable, and/or may be rotatable about its axis. Elongated body <NUM> may include a lumen (or multiple lumens) for positioning actuation wires within, for actuating end effector <NUM> via handle assembly <NUM> or actuating any other portion of apparatus <NUM>. Elongated body <NUM> may be configured to receive a plurality of actuation wires or a single actuation wire. In some examples, elongated body <NUM> may be fixedly coupled to end effector <NUM>, and in other examples elongated body <NUM> may be removably or releasably coupled to end effector <NUM>. Unless stated otherwise, any wire or actuation device described herein may extend from handle assembly <NUM> to end effector <NUM> via a lumen of elongated body <NUM>. Alternatively, or additionally, one or more of these actuation wires or devices may extend from handle assembly <NUM> to end effector <NUM> outside of (e.g., adjacent to) elongated body <NUM>. A catheter <NUM> (or any other sheath) including a lumen may extend distally from a distal end of handle assembly <NUM>. Elongated body <NUM> may be disposed within the lumen of catheter <NUM> and may move relative to catheter <NUM>. While catheter <NUM> is shown with a curved region in <FIG>, catheter <NUM> may be a straight sheath (e.g., such as a hypotube) having a rigidity sufficient to be moved proximally and distally within the body. Additionally, <FIG>, <FIG> may be shown without catheter <NUM> attached to the proximal end of a pivot arm <NUM> for ease of understanding (e.g., to visualize elongated body <NUM>).

Handle assembly <NUM> may include a handle <NUM> and a body <NUM>. Handle <NUM> may include a fixed portion 32a and an actuator portion 32b. Fixed portion 32a of handle <NUM> may be fixedly coupled to body <NUM>. Actuator portion 32b may include a circular or oval portion or ring for positioning a user's finger within, which may assist a user in holding handle assembly <NUM>. In some examples, actuator portion 32b of handle <NUM> may be an actuator which may be pivotally coupled to body <NUM> and movable relative to fixed portion 32a of handle <NUM>. In some examples, actuator portion 32b of handle <NUM> may be coupled to a proximal portion of an actuation wire, such as an actuation wire 40a, via an adjustable coupler <NUM>, as will be described herein. An anvil <NUM> of stapler device <NUM> may be actuated via actuation wire 40a, which extends between stapler device <NUM> and handle assembly <NUM>. In other examples, actuator portion 32b of handle <NUM> may be configured to control any other mechanism of apparatus <NUM>, such as operating an articulation lock of end effector <NUM>, actuation of the deployment of staples from stapler device <NUM>, or the like. It will be understood that wire 40a may have sufficient rigidity to be pushed in the distal direction and pulled in the proximal direction.

In some examples, handle assembly <NUM> may include a moveable cover <NUM> pivotally coupled to housing <NUM> at pivot point 38b. In <FIG>, cover <NUM> is shown in an open position, exposing the internal portions of body <NUM>. Cover <NUM> may be coupled to a proximal portion of body <NUM> and may cover the internal components of handle assembly <NUM> when positioned in a closed configuration, e.g., when a distalmost end 38a of cover <NUM> faces a surface 34a of body <NUM>. Cover <NUM> may be positioned to cover the internal components of body <NUM> (e.g., a closed configuration) via a coupling mechanism at a distal portion of cover <NUM> and a distal portion of handle assembly <NUM>, such as a snap-fit mechanism or the like. When in the closed configuration, cover <NUM> may form a pair of slots in body <NUM> (not shown). When the distal portion of cover <NUM> is uncoupled from the distal portion of body <NUM>, a user may rotate or pivot cover <NUM> at pivot point 38b in order to access to the internal components of handle assembly <NUM>.

Handle assembly <NUM> may include one or more adjustable couplers <NUM>, <NUM>, which may be configured to receive a portion of an actuation wire, such as actuation wire 40a. Any of adjustable couplers <NUM>, <NUM> may be a vice which is moveable in order to clamp down onto actuation wire 40a and fixedly couple actuation wire 40a to the adjustable couplers <NUM>, <NUM>. In some examples, adjustable couplers <NUM>, <NUM> may be moveable via a screw to adjust couplers <NUM>, <NUM> and couple or uncouple actuation wire 40a from couplers <NUM>, <NUM>. Couplers <NUM>, <NUM> may be used in the movement of additional wires described herein.

Adjustable coupler <NUM> may be coupled to longitudinal actuator <NUM> and moveable longitudinally via translating longitudinal actuator <NUM> within body <NUM>. Longitudinal actuator <NUM> may be partially positioned within housing <NUM> and may be slidable longitudinally within the two slots formed when cover <NUM> is positioned over the internal components of handle assembly <NUM>. Longitudinal actuator <NUM> may include a pair of opposing circular or oval portions or rings, with each circular portion defining an aperture for a user to position a respective finger within. In some examples, longitudinal actuator <NUM> may be coupled to an actuation wire (not shown), such as via adjustable coupler <NUM> or via a different coupler within body <NUM>, and may be configured to control staple deployment from stapler device <NUM>. In other examples, longitudinal actuator <NUM> may be configured to control any other mechanism of apparatus <NUM>, such as actuation of an anvil <NUM> of stapler device <NUM>, actuation of a locking mechanism associated with end effector <NUM>, or the like.

With continued reference to <FIG>, end effector <NUM> includes stapler device <NUM> which may be pivotally coupled to the distal end of elongated body <NUM>. For example, a connector <NUM> at a distal end of elongated body <NUM> may be pivotally attached to a proximal end of stapler device <NUM> via a pin 52a or the like. A pivot arm <NUM> may be pivotally attached to a side of a body <NUM> of stapler device <NUM> via a pin 60a. For example, one or more protrusions <NUM> may extend from the side of body <NUM> and may receive pin 60a through an opening in protrusion <NUM>, thereby fixing pin 60a relative to protrusion <NUM>. Pin 60a defines a pivot axis of stapler device <NUM> relative to pivot arm <NUM>. Pin 60a may also be received in an opening <NUM> at a distal end of pivot arm <NUM> (<FIG>), which may allow stapler device <NUM> to pivot relative to pivot arm <NUM>. Pivot arm <NUM> may be fixedly attached to a distal end of catheter <NUM> by ultrasonic welding, adhesive, crimping, or the like. This may prevent pivot arm <NUM> from moving when elongated member <NUM> is moved relative to catheter <NUM> and/or pivot arm <NUM>, as will be described herein. For ease of understanding, catheter <NUM> is shown only in <FIG>.

As shown in <FIG>, pivot arm <NUM> may include an opening <NUM> at a proximal end. Opening <NUM> may be connected to a lumen extending from the proximal end to the distal end of arm <NUM>. A slot <NUM> (e.g., an opening) (<FIG>) may be formed in a side of pivot arm <NUM> and may be connected to the lumen of pivot arm <NUM>. Slot <NUM> may be oval, rectangular, or any other suitable shape. Opening <NUM>, the lumen of pivot arm <NUM>, and slot <NUM> may be sized and shaped to receive a portion of elongated body <NUM>, such that elongated body <NUM> may enter pivot arm <NUM> via opening <NUM> and extend out of slot <NUM>. As will be described herein, movement of elongated body <NUM> relative to pivot arm <NUM> may cause stapler device <NUM> to rotate relative to pivot arm <NUM>. Pivot arm <NUM> shown in <FIG>, or aspects of pivot arm <NUM> including slot <NUM>, may be used with any end effector described herein. While pivot arm <NUM> is shown as a rectangular prism, pivot arm <NUM> may be any shape, including a cylinder, a rectangular prism with rounded edges, or the like.

Anvil <NUM> may be rotatably or pivotally coupled to body <NUM> via pin 120a (pin 120a may define a pivot axis). Anvil <NUM> and body <NUM> may be collectively referred to as jaws, grasping elements, and/or opposing members. Anvil <NUM> may extend distally towards a distal end of stapler device <NUM> from pin 120a. In some examples, anvil <NUM> may be rotatably biased about pin 120a and may be biased in an open configuration. For example, a distal end <NUM> of anvil <NUM> may biased away from body <NUM> using a spring or the like, thereby creating a space between distal end <NUM> of anvil <NUM> and a distal portion of body <NUM>. Anvil <NUM> may rotate about pin 120a and may contact or may approach body <NUM> in a closed position, e.g., to retain tissue between anvil <NUM> and body <NUM>. In some examples, body <NUM> may include a channel that supports a cartridge of staples or other fastening devices (not shown). The closed position of anvil <NUM> may provide a surface for which staples may be driven against when ejected from the cartridge of stapler device <NUM>. The cartridge may contain a plurality of surgical fasteners, such as staples, and the fasteners may be deployed from the cartridge when under the influence of a driving force exerted by an actuation sled or other actuation mechanism. Suitable staplers and associated actuation mechanisms are described in commonly-owned <CIT>.

With reference to <FIG>, pin 120a may extend from a side of anvil <NUM>, and pin 120a may be disposed in a slot <NUM> on a side of body <NUM>. For example, slot <NUM> may be disposed in an upper extension of body <NUM>. In addition to pivoting about pin 120a, anvil <NUM> may move in a longitudinal direction via pin 120a and slot <NUM>. For example, pin 120a of anvil <NUM> may move within slot <NUM>, which has a generally oval shape and extends in a longitudinal direction along a longitudinal axis. Slot <NUM> may be any shape, and may alternatively be a hole that fixes a longitudinal position of pin 120a. In the embodiment shown in <FIG>, when pin 120a is located at a distal end of slot <NUM>, anvil <NUM> may be positioned in the open configuration, and anvil <NUM> may be in the closed position when pin 120a is positioned at a proximal end of slot <NUM>. Wire 40a may be attached at a proximal end <NUM> of anvil <NUM> via an attachment mechanism 122a. Proximal movement of wire 40a may cause anvil <NUM> to move proximally, which may cause anvil <NUM> to rotate about pin 120a into the closed position. Distal movement of wire 40a may cause anvil <NUM> to move distally, which may cause anvil <NUM> to rotate about pin 120a into the open position.

<FIG> illustrates a top view of end effector <NUM> in the open configuration. A locking tab <NUM> is connected to anvil <NUM> via pin 120a and a second pin 120b, distal of pin 120a. Through those connections locking tab <NUM> moves with anvil <NUM>. It will be understood that locking tab <NUM> may be connected to anvil <NUM> via any other mechanism known in the art. According to an example, pin 120b may engage a second slot, distal to slot <NUM>, in the closed configuration, which may lock anvil <NUM> in the closed configuration.

Pivot arm <NUM> may include a pivot head <NUM> at the distal end thereof. Pivot head <NUM> may include a plurality of teeth 64a defining a plurality of spaces 64b therebetween. Locking tab <NUM> may engage spaces 64b, as will be described herein. Teeth 64a and spaces 64b may be spaced apart radially about a circumference of pivot head <NUM> (<FIG>) such that stapler device <NUM> may be locked at an angle relative to pivot arm <NUM>. For example, an angle α is defined as an angle between the longitudinal axis A-A of stapler device <NUM> and the longitudinal axis B-B of pivot arm <NUM>. When α is <NUM> degrees, pivot arm <NUM> may be approximately parallel to stapler device <NUM> (axes A-A and B-B are approximately parallel), and when α is <NUM> degrees, pivot arm <NUM> may be approximately perpendicular to stapler device <NUM> (axes A-A and B-B are approximately perpendicular). According to an example, teeth 64a and spaces 64b may be spaced such that stapler device <NUM> may be locked at an orientation relative to pivot arm <NUM> such that α may be one of approximately <NUM> degrees, approximately <NUM> degrees, approximately <NUM> degrees, and approximately <NUM> degrees. It will be understood that α is not limited to these angles. The number of teeth 64a and spaces 64b, and their spacing, may determine the various angles α of locking stapler device <NUM> relative to pivot head <NUM>. For example, teeth 64a may be positioned on pivot head <NUM> to change the angle of α. Further, the number of teeth 64a is not limited to three teeth 64a, as shown in <FIG>, and may be chosen based on the number of designed locking angles.

<FIG> illustrate anvil <NUM> in the closed configuration. In the closed configuration, anvil <NUM> has rotated about pin 120a such that distal end <NUM> of anvil <NUM> is closer to body <NUM> than in the open configuration. As shown in <FIG>, locking tab <NUM> may communicate with teeth 64a in the closed position to prevent relative rotational or pivotal movement between stapler device <NUM> and pivot arm <NUM>. For example, a proximal portion of locking tab <NUM> may be positioned between adjacent teeth 64a in the closed configuration, which may prevent stapler device <NUM> from rotating relative to pivot arm <NUM>.

A method of operating end effector <NUM> will now be described. End effector <NUM> may be advanced to a target site in a body via an incision or a natural orifice. End effector <NUM> is advanced in a closed configuration and subsequently opened via actuation of actuation wire 40a. In the open configuration, tissue at the target site may be placed between anvil <NUM> and body <NUM> (e.g., jaws) of stapler device <NUM>, via any suitable method. To properly orient stapler device <NUM>, a user may push distally or pull proximally on elongated body <NUM> to cause stapler device <NUM> to pivot about the axis defined by pin 60a until a desired orientation of stapler device <NUM> relative to pivot arm <NUM> is achieved (e.g., a desired angle α). The desired positioning/orientation of stapler device <NUM> may be assisted by an imaging device associated, for example, with an endoscope through which apparatus <NUM> is inserted. After the desired orientation is achieved, the user may move wire 40a in a proximal direction (e.g., pull on wire 40a) and thereby move anvil <NUM> into the closed configuration using, e.g., handle assembly <NUM>. As anvil <NUM> moves into the closed configuration, locking tab <NUM> may engage spaces 64b in a locked position and may prevent rotation of stapler device <NUM> about the axis defined by pin 60a. While in this locked position, the user may perform additional procedures, e.g., stapling, cutting, or other procedures on the tissue. Once the procedure is complete, the user may move (e.g., push) wire 40a in a distal direction, which may cause anvil <NUM> to move to the open position, thereby disengaging locking tab <NUM> from spaces 64b. The user may then rotate stapler device <NUM> to a new, different orientation relative to pivot arm <NUM>. If desired, the user may relock stapler device <NUM> in the new orientation by repeating this procedure or the user may remove the apparatus from the body.

A locking mechanism for an end effector <NUM>' according to another example is shown in <FIG> and <FIG>. End effector <NUM>' is similar to end effector <NUM>, and may include stapler device <NUM> pivotally connected to pivot arm <NUM>. Locking mechanism may include a pawl <NUM>' and a sprocket <NUM>' having a plurality of teeth 64a'. Spaces 64b' are defined between adjacent teeth 64a'. Sprocket <NUM>' may be rigidly connected to pivot arm <NUM> and may have an arc shape with a convex surface facing a proximal end of the end effector <NUM>. Pawl <NUM>' may be pivotally attached to body <NUM> of end effector <NUM> by a pin 66a'. A biasing member, e.g., a spring, may bias pawl <NUM>' in a distal direction, e.g., toward sprocket <NUM>'. Pawl <NUM>' may engage spaces 64b' to lock stapler device <NUM> in a desired orientation relative to pivot arm <NUM>. For example pawl <NUM>' may sit in any one of spaces 64b' between adjacent teeth 64a'. An actuation wire 40b may be attached to an end of pawl <NUM>' opposite an end of pawl <NUM>' connected to pin 66a'. Actuation wire 40b may be similar to wire 40a and may be moved proximally (e.g., pulled) and distally (e.g., pushed) to cause pawl <NUM>' to pivot about pin 66a'.

As with end effector <NUM>, end effector <NUM>' may be locked such that an orientation of stapler device <NUM> relative to pivot arm <NUM> is locked at one or more positions based on the number of teeth 64a' and spaces 64b', and the spacing of teeth 64a' and spaces 64b'. For example, when α is <NUM> degrees, pivot arm <NUM> may be parallel to end effector <NUM>' (axes A-A and B-B are approximately parallel), and when α is <NUM> degrees, pivot arm <NUM> may be perpendicular to end effector <NUM>' (axes A-A and B-Bare approximately perpendicular). It will be understood that angle α is not limited to these angles. Further, teeth 64a' and spaces 64b' are not limited to the number shown in <FIG> and <FIG>. The number of teeth 64a' and the number of spaces 64b' may be selected based on the number of possible positions stapler device <NUM> may be locked relative to pivot arm <NUM>. For example, teeth 64a' define seven spaces 64b' that provide different angles α between axes A-A and B-B. More or fewer spaces 64b' at different spacing may provide different angular adjustments of stapler device <NUM>.

A method of operating end effector <NUM>' will now be described. End effector <NUM>' may be introduced to the body and advanced to the target site in a similar manner as end effector <NUM>. Pawl <NUM>' is engaged with a space 64b' during insertion, so that angle α is approximately <NUM> degrees. Once end effector <NUM>' is adjacent the target site, the user may move actuation wire 40b in a proximal direction by, e.g., pulling on actuation wire 40b. Proximal movement of actuation wire 40b may cause pawl <NUM>' to rotate about pin 66a' and disengage pawl <NUM>' from a space 64b' and teeth 64a' of sprocket <NUM>'. After pawl <NUM>' is disengaged from space 64b' and teeth 64a', the user may orient stapler device <NUM> as desired relative to the tissue and/or target site in a manner similar to orienting stapler device <NUM> as discussed with reference to <FIG>, e.g., by moving elongated body <NUM> in a proximal or distal direction, thereby changing angle α. Once stapler device <NUM> is properly oriented, the user may release and/or push actuation wire 40b in the distal direction. For example, if pawl <NUM>' is biased toward sprocket <NUM>', releasing actuation wire 40b may cause pawl <NUM>' to engage a space 64b' between teeth 64a'. Alternatively, or additionally, a distal force applied to actuation wire 40b may be necessary for such engagement. Once pawl <NUM>' engages a space 64b' between teeth 64a', stapler device <NUM> may be locked in the selected orientation and the user may perform additional procedures. For example, the user may then move anvil <NUM> from the open configuration to the closed configuration by moving actuation wire 40a proximally and/or may perform additional medical procedures, e.g., stapling, cutting, or other procedures on the tissue. To change the orientation of stapler device <NUM> relative to pivot arm <NUM>, pawl <NUM>' may again be disengaged from teeth 64a' and stapler device <NUM> may be rotated about the axis defined by pin 60a as described herein. Locking mechanism <NUM>' of <FIG> and <FIG> permits locking of stapler device <NUM> relative to pivot arm <NUM>, independent of opening and closing of anvil <NUM>.

A locking mechanism for an end effector <NUM>" according to another example is described with reference to <FIG>. End effector <NUM>" is similar to end effectors <NUM> and <NUM>', e.g., may include stapler device <NUM> and pivot arm <NUM>. The locking mechanism may include a ball-nose spring plunger <NUM>", including a housing <NUM> fixed to body <NUM> of stapler device <NUM>. Ball-nose spring plunger <NUM>" may include detents 64c" (notches) disposed on a distal end of pivot arm <NUM>, a biasing member 64a" (e.g., a spring, a threaded housing having a spring and a ball-bearing or a plunger, or any other biasing member) disposed in (or on) housing <NUM> and configured to extend out of a proximal end of housing <NUM>, and a ball bearing 64b". Ball bearing 64b" is inserted within an interior of biasing member 64a" so that ball bearing 64b" is held by biasing member 64a", rotates relative to biasing member 64a", and protrudes from an end of biasing member 64a".

As described herein, movement of elongated body <NUM> relative to pivot arm <NUM> may rotate end effector <NUM>" about the axis defined by pin 60a. Distal movement of elongated body <NUM> may increase angle α and may cause biasing member 64a" to be compressed within housing <NUM>. For example, as angle α increases, stapler device <NUM> rotates about the axis defined by pin 60a, which may cause the protruding material between detents 64c" (teeth) to push against ball bearing 64b", thereby compressing biasing member 64a" into housing <NUM>. Biasing member 64a", ball bearing 64b", and detents 64c" may cooperate to lock stapler device <NUM> at different orientation angles α relative to pivot arm <NUM>. For example, a friction force holds ball bearing 64b" within the corresponding detent 64c". As stapler device <NUM> is rotated about the axis defined by pin 60a, biasing member 64a" is compressed until the friction force between detent 64c" and ball bearing 64b" is overcoming. Overcoming this friction force causes ball bearing 64b" to move from the first detent 64c" to a second detent 64c", adjacent the first detent 64c". Once ball bearing 64b" moves to the second detent 64c", biasing member 64a" expands back to the original length/position. Additional distal movement of elongated body <NUM> may cause stapler device <NUM> to pivot about the pivot axis defined by pin 60a, causing biasing member 64a" to again compress. As biasing member 64a" is compressed, ball bearing 64b" is moved from the second detent 64c" to a third detent 64c", adjacent the second detent 64c". Continued distal movement of elongated body <NUM> causes angle α between axes A-A and B-B to increase. Alternatively, or additionally, the distal end of end effector <NUM>" may be pushed against tissue to provide additional leverage and assist in changing angle α.

To decrease angle α, a force on elongated body <NUM> in the proximal direction (e.g., a pulling force) must be sufficient to overcome the frictional forces between ball bearing 64b" and detents 64c". When the friction force is overcome, stapler device <NUM> moves relative to pivot arm <NUM> such that angle α decreases. The number of detents 64c" and the spacing between adjacent detents 64c" may be selected based on the number of possible positions stapler device <NUM> may be locked relative to pivot arm <NUM>. A smaller ball bearing and smaller detents may result in finger adjustments of angle α and more options for angle α.

A method of operating end effector <NUM>" will now be described. End effector <NUM>" may be introduced to the body and advanced to the target site in a similar manner as end effectors <NUM> and <NUM>'. End effector <NUM> is advanced to the target site in a closed position and is opened by actuation of actuation wire 40a. During insertion, ball bearing 64b" may be engaged with a first detent 64c" so that angle α is approximately <NUM> degrees, e.g., so that axes A-A and B-B are approximately parallel. Once end effector <NUM>" is adjacent the target site, the user may rotate stapler device <NUM> about the pivot axis defined by pin 60a by pushing elongate member <NUM> in the distal direction. The distal movement of elongate member <NUM> may cause angle α to increase and may cause biasing member 64a" to compress within housing <NUM>. As biasing member 64a" is compressed from the original length into housing <NUM>, a second detent 64c", adjacent to the first detent 64c", engages ball bearing 64b" and biasing member 64a" expands to the original length. Friction forces between ball bearing 64b" and the second detent 64c" lock stapler device <NUM> relative to pivot arm <NUM>. The user may continue to push elongated member <NUM> in the distal direction until a desired orientation of stapler device <NUM> relative to pivot arm <NUM>, e.g., a desired angle α, is achieved.

To decrease the angle α, elongated member <NUM> may be pulled in a proximal direction. Such movement causes spring 64b" to be compressed into housing <NUM>, moving ball bearing 64b" from, e.g., the second detent 64c" to the first detent 64c". In this manner, the orientation of stapler device <NUM> relative to pivot arm <NUM> may be selected and locked. Locking mechanism <NUM>" of <FIG> permits locking and unlocking of stapler device <NUM> relative to pivot arm <NUM>, independent of opening and closing of anvil <NUM>.

It will be understood that any of the locking mechanisms described herein may be used alone or in combination with one or more other locking mechanisms described herein.

While different medical systems have been described, it will be understood that the particular arrangements of elements in these fastening systems are not limited. Moreover, a size, a shape, and/or the materials of the fastening system are not limited. As described herein, there are included various locking mechanisms for maintaining an orientation of a fastening device of an end effector. For example, in certain procedures, performing various medical procedures may be improved by ensuring proper orientation of the end effector relative to the endoscope and, thus, relative to the target site/tissue.

Claim 1:
A medical device (<NUM>), comprising:
an end effector (<NUM>, <NUM>', <NUM>") at a distal end of the medical device;
an actuator (<NUM>) coupled to a proximal end of the end effector (<NUM>, <NUM>', <NUM>");
a pivot arm (<NUM>) pivotally coupled to the end effector (<NUM>, <NUM>', <NUM>") distal of the proximal end of the end effector (<NUM>, <NUM>', <NUM>"), wherein actuation of the actuator pivots the end effector relative to the pivot arm;
characterized in that the medical device (<NUM>) further comprises:
a lock on the end effector and the pivot arm (<NUM>), wherein the lock has a first state permitting the end effector (<NUM>, <NUM>', <NUM>") to pivot relative to the pivot arm (<NUM>) and a second state restricting the end effector (<NUM>, <NUM>', <NUM>") from pivoting relative to the pivot arm (<NUM>).