Locking mechanism for hemostatic clips

Abstract

The applicator of the clip system includes an elongate member, a bushing coupled to a distal end of the elongate member, and a coupling portion movably attached to the bushing. A capsule is coupled to the coupling portion via a coupling member that engages a hook of the coupling portion. Proximal ends of a pair of clip arms are received within the capsule, and a core member received and connected between the proximal ends of the pair of clip arms includes a protrusion and a break point distal to the protrusion. The core member is coupled to a control member such that movement of the control member relative to the elongate member opens and closes the pair of clip arms. The protrusion is configured such that when the clip is clipped on tissue, the coupling portion retracts into the body portion, causing the protrusion to move the coupling member radially outward from the hook to release the capsule.

Description

[Technical field]

[0001] The present disclosure relates to an endoscopic device, and more particularly, to an endoscopic clipping device for treating tissue along the gastrointestinal tract. This disclosure claims priority to U.S. Provisional Patent Application No. 63 / 377,260, filed Sep. 27, 2022, the disclosure of which is incorporated herein by reference. [Background technology]

[0002] In gastrointestinal (GI) procedures, or for procedures in other body lumens, it is often necessary to close a tissue opening. Currently, such openings are often closed using hemostatic clips. However, some of these clips can become lodged in the tissue opening being treated or cause dislodged parts on the deployed tissue that can be harmful to the patient. Summary of the Invention

[0003] The present disclosure relates to a clipping system for treating tissue. The system includes an applicator, a clip, and a core member. The applicator includes a flexible elongate member extending from a proximal end that remains outside a living body in use to a distal end that is inserted into the living body in use to a location adjacent a target tissue to be clipped. The applicator includes a control member extending through the applicator and a bushing coupled to a distal end of the flexible elongate member, the bushing including a proximal body portion coupled to the distal end of the flexible elongate member and a distal coupling portion movably attached to the proximal body portion.

[0004] The clip includes a capsule releasably coupled to the distal coupling portion of the bushing via a first coupling member of the capsule that engages a corresponding first hook of the distal coupling portion of the bushing, the capsule including a channel therethrough, and the clip includes a pair of clip arms having proximal ends slidably received within the channel for movement between an open configuration in which the distal ends of the pair of clip arms are separated from one another to receive tissue between the distal ends of the pair of clip arms and a closed configuration in which the distal ends of the pair of clip arms are drawn toward one another to grasp tissue.

[0005] The core member is received between and connected to the proximal ends of the pair of clip arms and includes a first lateral projection and a first break point distal to the first lateral projection, the first break point separating a distal portion of the core member from a proximal portion of the core member. The core member is coupled to a distal end of the control member such that longitudinal movement of the control member relative to the flexible elongate member moves the pair of clip arms between the open configuration and the closed configuration. The lateral extent of the first lateral projection is selected such that when the clip is clipped on a target tissue, the first lateral projection is retracted proximally to move the distal coupling portion into the proximal body portion of the bushing and the first lateral projection can move the first coupling member radially outward beyond an outer end of the first hook to release the capsule from the bushing.

[0006] In one embodiment, the core member includes a first pin received within a hole in a proximal portion of a first clip arm of the pair of clip arms and a second pin received within a hole in a proximal portion of a second clip arm of the pair of clip arms.

[0007] In one embodiment, the distal coupling portion is slidably coupled to the proximal body portion of the bushing for proximal and distal movement in and out of the distal end of the proximal body portion.

[0008] In one embodiment, the proximal body portion of the bushing includes a proximal portion having an outer diameter substantially equal to an outer diameter of the flexible elongate member, and a distal portion of the proximal body portion of the bushing has an outer diameter substantially equal to an outer diameter of the capsule.

[0009] In one embodiment, the inner diameter of the channel is substantially equal to the inner diameter of the distal portion of the proximal body portion of the bushing. In one embodiment, the lateral extent of the first lateral projection is selected to be substantially equal to the inner diameter of the channel and the inner diameter of the distal portion of the proximal body portion of the bushing, and the proximal portion of the distal coupling has an inner diameter slightly smaller than the inner diameter of the channel and the inner diameter of the distal portion of the proximal body portion of the bushing such that the first lateral projection latches against the distal coupling within the bushing.

[0010] In one embodiment, the core member includes a second break point proximal to the first break point, and the core member defines the distal portion distal to the first break point, an intermediate portion between the first break point and the second break point, and the proximal portion proximal to the second break point.

[0011] In one embodiment, the pair of clip arms are configured to define a proximal-most position of the pair of clip arms within the capsule, and when a proximal tension applied to the control member after the pair of clip arms reach the proximal-most position exceeds a first threshold level, the core member separates at the first break point to allow the intermediate portion and the proximal portion of the core member to move proximally thereby pulling the first lateral projection proximally away from the capsule and moving the first coupling member of the capsule radially outward beyond an outer end of the first hook of the distal coupling portion of the bushing to separate the capsule from the bushing.

[0012] The present disclosure also relates to an apparatus for clipping tissue. The apparatus includes a bushing including a proximal body portion configured to be coupled to a distal end of a flexible applicator and a distal coupling portion movably attached to the proximal body portion and including a first hook. The apparatus also includes a clip including a capsule and a pair of clip arms. The capsule is releasably coupled to the distal coupling portion via a first coupling member of the capsule that engages the first hook. The capsule includes a channel therethrough. Proximal ends of the pair of clip arms are slidably received within the channel for movement between an open configuration in which the distal ends of the pair of clip arms are separated from one another to receive tissue between the distal ends of the pair of clip arms and a closed configuration in which the distal ends of the pair of clip arms are drawn together to grasp tissue. The apparatus also includes a core member received between and connected to the proximal ends of the pair of clip arms and including a first lateral projection and a first break point distal to the first lateral projection. The first break point separates a distal portion of the core member from a proximal portion of the core member. The core member is coupled to a distal end of a control member configured such that longitudinal movement of the control member relative to the flexible applicator moves the pair of clip arms between the open and closed configurations. The lateral extent of the first lateral projection is selected such that when the clip is clipped on a target tissue, the first lateral projection retracts proximally to move the distal coupling portion into the proximal body portion of the bushing and allows the first lateral projection to move the first coupling member radially outward beyond an outer end of the first hook to release the capsule from the bushing.

[0013] In one embodiment, the core member includes a first pin received within a hole in a proximal portion of a first clip arm of the pair of clip arms and a second pin received within a hole in a proximal portion of a second clip arm of the pair of clip arms.

[0014] In one embodiment, the distal coupling portion is slidably coupled to the proximal body portion of the bushing for proximal and distal movement in and out of the distal end of the proximal body portion.

[0015] In one embodiment, the proximal body portion of the bushing includes a proximal portion having an outer diameter substantially equal to an outer diameter of the flexible applicator, and a distal portion of the proximal body portion of the bushing has an outer diameter substantially equal to an outer diameter of the capsule.

[0016] In one embodiment, the inner diameter of the channel is substantially equal to the inner diameter of the distal portion of the proximal body portion of the bushing. In one embodiment, the lateral extent of the first lateral projection is selected to be substantially equal to the inner diameter of the channel and the inner diameter of the distal portion of the proximal body portion of the bushing, and the proximal portion of the distal coupling has an inner diameter slightly smaller than the inner diameter of the channel and the inner diameter of the distal portion of the proximal body portion of the bushing such that the first lateral projection latches against the distal coupling within the bushing.

[0017] In one embodiment, the core member includes a second break point proximal to the first break point, and the core member defines the distal portion distal to the first break point, an intermediate portion between the first break point and the second break point, and the proximal portion proximal to the second break point.

[0018] The present disclosure also relates to a method for clipping tissue, the method including inserting a distal portion of a flexible elongate member into a living body adjacent a target tissue to be clipped while maintaining a proximal end of the flexible elongate member outside the living body. A control member extends through an applicator. A bushing coupled to a distal end of the flexible elongate member includes a proximal body portion coupled to the distal end of the flexible elongate member and a distal coupling portion movably attached to the proximal body portion. The method includes positioning a clip coupled to the bushing adjacent the target tissue. The clip includes a capsule and a pair of clip arms. The capsule is releasably coupled to the distal coupling portion of the bushing via a first coupling member of the capsule that engages a corresponding first hook of the distal coupling portion of the bushing. The capsule includes a channel extending therethrough. Proximal ends of the pair of clip arms are slidably received within the channel. The method includes actuating the pair of clip arms to an open configuration by distally moving the control member relative to the flexible elongate member. In the open configuration, distal ends of the pair of clip arms are separated from one another to receive tissue therebetween. The method includes actuating the pair of clip arms to a closed configuration by proximally retracting the control member relative to the flexible elongate member. In the closed configuration, the distal ends of the pair of clip arms are drawn toward one another such that the target tissue is grasped by the pair of clip arms. The method includes further proximally retracting the control member to increase tension applied to a core member coupled to a distal end of the control member and received and connected between the proximal ends of the pair of clip arms until the tension reaches a predetermined level. At the predetermined level, a distal portion of the core member is separated from a proximal portion of the core member.The lateral extent of the first lateral projection of the proximal portion of the core member is selected such that when the distal portion of the core member separates from the proximal portion of the core member, the first lateral projection is retracted proximally to move the distal coupling portion into the proximal body portion of the bushing and to move the first coupling member radially outwardly beyond the outer end of the first hook to release the capsule from the bushing.

[0019] In one embodiment, the distal coupling portion is slidably coupled to the proximal body portion of the bushing for proximal and distal movement in and out of the distal end of the proximal body portion.

[0020] In one embodiment, the inner diameter of the channel is substantially equal to the inner diameter of the distal portion of the proximal body portion of the bushing. In one embodiment, the lateral extent of the first lateral projection is selected to be substantially equal to the inner diameter of the channel and the inner diameter of the distal portion of the proximal body portion of the bushing, and the proximal portion of the distal coupling has an inner diameter slightly smaller than the inner diameter of the channel and the inner diameter of the distal portion of the proximal body portion of the bushing such that the first lateral projection latches against the distal coupling within the bushing.

[0021] In one embodiment, the core member includes a second break point proximal to the first break point, and the core member defines the distal portion distal to the first break point, an intermediate portion between the first break point and the second break point, and the proximal portion proximal to the second break point. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 illustrates a side view of a distal portion of a clipping system according to an exemplary embodiment of the present disclosure, with components of the clipping system separated from one another. [Diagram 2]FIG. 2 shows a side view of the components that connect the control wires to the clips of the exemplary system of FIG. 1 with the clip capsule removed. [Diagram 3] FIG. 3 shows a side view of the clip according to the embodiment of FIG. [Figure 4A] FIG. 4A shows a side view of a bushing according to the embodiment of FIG. 1 coupled to a capsule of a clip. [Figure 4B] FIG. 4B shows a side view of the bushing of FIG. 4A separated from the capsule of the clip. [Figure 5A] 5A shows an exploded side view of a distal portion of the clipping system of FIG. 1. FIG. [Figure 5B] FIG. 5B shows an exploded side view of the distal portion of the clipping system of FIG. 1 rotated 90 degrees relative to FIG. 5A. [Figure 6] FIG. 6 shows a partial cross-sectional view of a distal portion of the clipping system of FIG. [Figure 7A] FIG. 7A shows the bushing of the system of FIG. 1 with the movable portion of the bushing separated from the proximal portion of the bushing. [Figure 7B] FIG. 7B shows the bushing of FIG. 7A rotated 90 degrees relative to FIG. 7A. [Figure 8] FIG. 8 shows a partial cross-sectional view of a distal portion of the clipping system of FIG. 1, including the distal end of the applicator. [Figure 9] FIG. 9 shows a partial cross-sectional view of a distal portion of the clipping system of FIG. 1, including the distal end of the applicator and the distal ends of the arms of the clip. [Figure 10] FIG. 10 shows a partial cross-sectional view of the distal portion of the clipping system of FIG. 1, including the distal end of the applicator with the clip capsule separated from the bushing and the distal portion of the core member severed from the intermediate portion of the core member. [Figure 11] FIG. 11 shows a partial cross-sectional view of the distal portion of the clipping system of FIG. 1, including the distal end of the applicator with the clip capsule separated from the bushing and the intermediate portion of the core member severed from the proximal portion of the core member. [Figure 12A]FIG. 12A shows a partial cross-sectional view of a distal portion of the clipping system of FIG. 1 in a tissue-receiving open configuration, including a locking arrangement for closing and locking the clip in a tissue-clipping configuration. [Figure 12B] FIG. 12B shows a partial cross-sectional view of a distal portion of the clipping system of FIG. 1 in a tissue clipping closed configuration, including a locking arrangement for closing and locking the clip in the tissue clipping configuration. [Figure 13A] FIG. 13A shows a side view of a core member according to a further embodiment. [Figure 13B] FIG. 13B shows a side view of the core member of FIG. 13A rotated 90 degrees relative to FIG. 13A. [Figure 14] FIG. 14 is a partial cross-sectional view of a distal portion of a clipping system including a core member as shown in FIGS. 13A and 13B, showing the distal end of the applicator with the clip capsule separated from the bushing and the distal portion of the core member severed from the proximal portion of the core member. [Figure 15] FIG. 15 shows a partial cross-sectional view of the clipping system of FIG. 14, including a handle, an applicator, and a clip. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The present disclosure may be further understood with reference to the following description and the accompanying drawings. In this disclosure, like elements are referred to by the same reference numerals. The present disclosure relates to an endoscopic clipping system for treating internal tissue perforations, defects, and / or bleeding. An exemplary embodiment of the present disclosure describes a clipping system with a clip releasably coupled to a proximal portion of the system. The clip includes a pair of clip arms. The proximal ends of the pair of clip arms are slidable within a capsule such that the pair of clip arms move between an open configuration and a closed configuration. In the open configuration, the distal ends of the pair of clip arms are separated from each other to receive the target tissue therebetween. In the closed configuration, the distal ends of the pair of clip arms are retracted within a capsule such that the distal ends of the pair of clip arms move toward each other to grasp the target tissue therebetween. The clipping system includes a novel mechanism for separating the clip from the applicator to minimize the risk of dislodgement and reduce the length of the clip.

[0024] An exemplary clipping system includes an applicator including a flexible member extending from a handle to a distal end that is releasably coupled to the clip. The applicator includes a flexible elongate member extending from the handle, with a control member slidably received within the applicator. The control member is coupled to an actuator on the handle that allows a user to move the control member proximally and distally within the elongate member. A capsule of the clip is coupled to a distal end of the elongate member. The distal end of the control member is coupled to a one-piece member that is slidable within the capsule and couples the control member to the arms of the clip. Movement of the control wire moves the one-piece member proximally and distally to extend and retract the arms of the clip from and into the capsule, thereby moving the arms between a tissue-receiving open configuration and a tissue-clipping closed configuration.

[0025] A user deploys the clip by closing the clip arms over a target portion of tissue and applying a proximal force to the one-piece member through the control member until a break point on the one-piece member breaks, at which point the clip arms are locked in a tissue-clipping closed configuration and the portion of the one-piece member proximal to the break point is retracted proximally from the capsule, separating the capsule from the elongate member.

[0026] As will be described in more detail below, the portion of the one-piece member proximal to the break point includes a protrusion extending radially outward therefrom that is configured to engage and bend a radially outer portion of the proximal end of the capsule that is pre-bent over a tab at the distal end of the bushing to releasably couple the bushing to the capsule. Thus, once the proximal portion of the one-piece member separates from the distal portion of the one-piece member effectively separating the clip arms from the control member and separating the capsule from the bushing, the clip separates completely from the applicator allowing the applicator to be removed from the body leaving the clip clipped in place on the target tissue.

[0027] As described in more detail below, the structure of the integral member and bushing allows for the containment of the cut proximal portion of the integral member within the bushing. This allows for the construction of a clip with a shorter capsule and reduces the overall length of the clip compared to many clips available on the market, such as the Resolution™ and Resolution360™ clips available from Boston Scientific Cymed. As one skilled in the art can appreciate, a shorter clip may improve visualization of the target site and allow for better maneuverability, for example, when placing multiple clips. In some current clip designs, a shed portion may occur during the deployment process that separates the clip from the catheter, and the shed portion may be left inside the body to pass through the GI tract. The embodiments described herein minimize the risk of shed parts. Specifically, the control member is configured to have a break stress that is significantly higher than the break stress of the integral member. Also, the cut proximal portion of the integral member is contained within the bushing during deployment and is withdrawn from the body. Thus, the distal end of the control member is not severed from the proximal portion of the control member and the control between the one-piece member and the distal end of the control member is controlled to prevent it becoming a missing part.

[0028] 1-11 and 15 illustrate a clipping system 100 for treating tissue defects, including a clip 102 releasably coupled to an insertion device, such as an applicator 104 (see FIGS. 8-11) (e.g., a catheter or other flexible tube). Clip 102 includes a pair of clip arms 106 having proximal ends 108 coupled to one another via a core member 110 that is slidably received within a capsule 112 for movement of clip 102 between an open configuration in which distal ends 114 of clip arms 106 are separated from one another to receive tissue therebetween, and a closed configuration in which distal ends 114 of clip arms 106 are drawn together to grasp tissue therebetween.

[0029] The clip arms 106 are actuated between an open configuration and a closed configuration via a control member 116, with a distal end 118 of the control member 116 received within a cavity 120 of the core member 110, while a proximal portion 122 of the control member 116, which has a reduced dimension, extends proximally from the cavity 120 and projects out of the core member 110 (see FIG. 2). As shown in FIG. 15, the proximal portion 122 of the control member 116 extends through the applicator 104 to a proximal end accessible to a user of the system 100. In this embodiment, the distal end 118 of the control member is enlarged (i.e., has an increased diameter) relative to the proximal portion 122 of the control member 116. As seen in FIG. 5B, the core member 110 includes an opening 119 having a size and shape that allows the distal end 118 to pass therethrough.

[0030] The distal end 118 is mounted within a cavity 120 sized and shaped to snugly receive the distal end 118 as the control member 116 is rotated. In this embodiment, both the distal end 118 and the cavity 120 are substantially cylindrical, with the cavity 120 being slightly larger than the distal end 118 by an allowance to allow the distal end 118 to be securely mounted therein. As seen in FIG. 5B, a longitudinal recess 117 is formed on the side of the core member 110 opposite the side on which the cavity 120 is formed, and extends proximally from the opening 119 such that when the distal end 118 is rotated into position within the cavity 120, a distal-most portion of the proximal portion 122 of the control member 116 is mounted within the longitudinal recess 117. Thus, when the user moves the control member 116 longitudinally (i.e., proximally and distally) relative to the applicator 104, the distal end 118 engages the proximal and distal ends 120p and 120d of the cavity 120, respectively, thereby moving the core member 110 and the clip arms 106 proximally and distally relative to the capsule 112, thereby moving the clip 102 between the open and closed configurations.

[0031] In particular, when the clip arms 106 move out of the capsule 112 due to distal movement of the control member 116 relative to the capsule 112, the clip arms 106 spring back apart (e.g., under a natural bias imparted to the clip arms 106). In one embodiment, each of the clip arms 106 is formed from a resilient material, such as Nitinol, and is pre-formed (e.g., thermoformed) into a shape that matches the shape of the clip arms 106 when in the open configuration. Thus, the clip arms 106 spring back apart into the open configuration when not constrained by the capsule 112 to maintain the closed configuration.

[0032] As described in more detail below, clip 102 is releasably coupled to applicator 104 via a bushing 128 coupled to a distal end of applicator 104, such that applicator 104 and bushing 128 form an applicator that is inserted through an insertion instrument (e.g., a flexible endoscope) to a target site within a living body. The portion of applicator 104 extending proximally from bushing 128 to handle 101 (see FIG. 15 ) is formed in this embodiment as a coil 105 of flexible material, such as stainless steel, which allows applicator 104 to navigate the tortuous paths traversed by even the most flexible endoscopes.

[0033] The desired orientation of the clip arms 106 within the capsule 112 is maintained in this embodiment by tabs 121 formed as part of the capsule 112 that fold radially inward across the distal opening of the capsule 112 and are received between the clip arms 106. The size of the tabs 121 is selected so that the space allowed for each clip arm 106 at the open distal end of the capsule 112 is sufficient to allow the clip arm 106 to slide in and out of the capsule 112 only when aligned with the tabs 121. The proximal end 108 of each clip arm 106 is coupled to the distal end of the core member 110 via pins 111 that extend radially outward from either side of the core member 110.

[0034] Each of the pins 111 is threaded through an opening 107 in the proximal end of a corresponding one of the clip arms 106, which causes the clip arms 106 to move proximally and distally within the capsule 112 as the control member 116 moves proximally and distally through the applicator 104. Thus, movement of the control member 116 relative to the applicator 104 causes the clip arms 106 to move proximally into and distally out of the capsule 112, thereby moving the clip arms 106 between an open configuration and a closed configuration. Additionally, the connection between the pins 111 and the clip arms 106 maintains the desired orientation of the core member 110 within the capsule 112, as the clip arms 106 are held in a desired orientation within the capsule 112 by the tabs 121.

[0035] As discussed above, the applicator 104 includes a bushing 128 at its distal end for releasably coupling the applicator 104 to the clip 102. The control member 116 extends distally through the applicator 104 and into the bushing 128 where it connects to the core member 110 as discussed above. As seen in Figures 5A and 5B, the bushing 128 in this embodiment includes a proximal portion 130 having an outer diameter equal to the outer diameter of the distal end of the coil 105, and a distal portion 132 having a reduced outer diameter relative to the proximal portion 130. The outer diameter of the distal portion 132 in this embodiment is equal to the outer diameter of the capsule 112.

[0036] As one skilled in the art would understand, the coil 105, bushing 128, and capsule 112 in this embodiment are all generally cylindrical. However, the shapes of these components can be modified in any desired manner so long as the applicator and clip 102 can be inserted through a working channel of a delivery device (e.g., a flexible endoscope) and manipulated as desired without damaging the delivery device. The bushing 128 in this device operates to ensure that the clip 102 is fully separated from the applicator 104 after the user deploys the clip 102, while also eliminating any lost parts. In particular, it is important that the applicator 104 is fully separated from the clip 102 after deployment to prevent a situation in which the clip 102 becomes locked and gripped on tissue within the body while the applicator remains connected to the clip. As one skilled in the art would understand, if the applicator 104 cannot be so separated from the clip 102, a separate procedure may be required to separate the clip from the clipped tissue or the applicator.

[0037] In this embodiment, the bushing 128 includes a moving coupling 134 that is slidably received within the distal portion 132. A pair of pins 136 extending radially outward from opposite sides of the moving coupling 134 in this embodiment are received within corresponding slots 138 that extend longitudinally through a portion of each of the opposite sides of the distal portion 132, allowing the moving coupling 134 to slide proximally and distally within the distal portion 132 along a distance defined by the slots 138. The moving coupling 134 includes a pair of distally extending wings 140, each of which defines two recesses 142 (see FIGS. 7A and 7B), each of which is sized and positioned to receive a corresponding locking mechanism at the proximal end 113 of the capsule 112.

[0038] In this embodiment, the locking mechanism of the capsule is formed as a series of openings 144 formed between a proximal web 146 and a proximal end 148 of a cylindrical portion of the capsule 112. Prior to assembly, the proximal end of the capsule 112 is substantially cylindrical, and when the moving coupling 134 is inserted into the capsule 112, the proximal end of the capsule is compressed radially inward, thereby forcing each of the webs 146 into a corresponding one of the recesses 142 and each of a plurality of tabs 150 (four tabs 150 in this embodiment) of the moving coupling 134 extending distally of the recesses 142 are received within a corresponding one of the openings 144 to releasably lock the capsule 112 to the bushing 128. As can be seen in FIGS. 5A and 7B, the wings 140 of the moving coupling 134 are separated from one another via slots 152 that each extend longitudinally from an open distal end 154 to a closed proximal end 156. In this configuration, the web 146 extends across the slot 152 .

[0039] The core member 110 of this embodiment includes a proximal portion 158 coupled to an intermediate portion 162 extending distally from the proximal portion 158 and coupled to the proximal portion 158 by a first break point 164. A distal portion 166 extending distally from the intermediate portion 162 is coupled to the intermediate portion 162 via a second break point 168. The proximal portion 158 includes a longitudinal recess 117 with an opening 119 and a cavity 120, while the intermediate portion 162 includes a pair of diametrically opposed lateral projections 160 extending outwardly a distance selected to substantially match the inner diameter of the capsule 112 as well as the inner diameter of the distal portion 132 of the bushing 128. The distal portion 166 includes a pin 111 and two opposing surfaces 268 into which the proximal ends 108 of the clip arms 106 are received.

[0040] As described below, each lateral projection 160 is movable to contact and bend radially outward a corresponding portion of the capsule 112 that is locked to the distal portion of the bushing 128. When pulled proximally from the capsule 112, the lateral projections 160 bend those portions of the capsule 112 radially outward beyond the extent of the portion of the bushing 128 to which they were locked, thereby releasing the capsule 112 from the bushing 128. Thus, the lateral projections 160 preferably extend radially outward a distance greater than the radial extent of the portion of the bushing 128 to which the capsule 112 is locked, thereby pushing those portions of the capsule radially outward beyond that portion of the bushing 128. As described below, it may be desirable to configure the lateral projections 160 to extend radially outward to slide over an inner surface of the capsule 112 to allow maximum radially outward expansion of the locked portions of the capsule 112.

[0041] The core member 110 and bushing 128 of this embodiment cooperate to properly separate the clip 102 from the applicator 104 upon deployment to lock the clip 102 onto the target tissue so that the applicator 104 can be withdrawn from the body while the clip 102 remains clipped in place on the target tissue. Specifically, when the clip 102 is assembled, the core member 110 along with the clip arms 106 are maintained in a desired orientation within the capsule 112 via the tabs 121. In this desired orientation, the intermediate and distal portions 162, 166 of the core member 110 are each received within the capsule 112, and the lateral projections 160 are aligned with the slots 152 in the distal portion 132 of the bushing 128.

[0042] 12A and 12B, each of the clip arms 106 of the clip 102 in this embodiment includes a locking mechanism at its proximal end 108. In this embodiment, the locking mechanism of each clip arm 106 is formed as a tab 172 that biases the proximal end 108 of the clip arm 106 to spring back radially outward. The proximal end 108 of the clip arm 106 is restrained in a radially inward position where the tab 172 is spaced from the capsule 112 by the overhang of the lateral projections 160. Thus, while the clip 102 is operated between the open and closed configurations and the core member 110 remains intact, the lateral projections 160 maintain the proximal end 108 and the tab 172 in the unlocked configuration such that the clip 102 can be opened and closed until a desired portion of tissue is grasped by the clip 102. Once the user determines that the target portion of tissue has been gripped as desired and clip 102 should be deployed, the user manipulates the actuator on handle 101, causing proximal portion 158 and intermediate portion 162 of core member 110, including lateral projections 160, to move proximally relative to clip 102, respectively, until tension on control member 116 and core member 110 exceeds a predetermined level at which core member 110 breaks at second break point 168, as described in more detail below. As a result, tabs 172 are free to spring back radially outward when lateral projections 160 no longer overhang proximal ends 108 of clip arms 106.

[0043] The tabs 172 are positioned to spring back outward into windows 174 formed adjacent the proximal end 113 of the capsule when the clip arms 106 are retracted proximally into the capsule 112 to their full extent and the lateral projections 160 are withdrawn from the capsule 112. Each of the tabs 172 engages the distal surface of a corresponding one of the windows 174 such that the clip arms 106 are locked in a closed configuration gripping the target tissue. Those skilled in the art will appreciate that this locking mechanism is merely exemplary and that various known clip locking mechanisms can be substituted for this exemplary mechanism. The proximal and intermediate portions 158, 162 of the core member 110 are each retracted into the bushing 128 and the distal portion 166 of the core member 110 is retained within the capsule 112 such that deployment of the clip 102 does not result in any lost portions.

[0044] As will be appreciated by one of ordinary skill in the art, in use, a user advances the clip 102 (e.g., by advancing the applicator 104 and clip 102 through a working channel of a flexible endoscope) to a target site adjacent the target tissue to be clipped. Once the clip 102 is positioned as desired, the user advances the control member 116 distally relative to the applicator 104 (e.g., via a thumb ring and slider on the handle 101) to move the core member 110 and clip arms 106 distally through the capsule 112. As the clip arms 106 protrude distally from the capsule 112, the clip arms 106 spread apart under their natural bias into a tissue-receiving open configuration. The clip 102 is then further advanced distally until the distal ends 114 of the clip arms 106 contact the target tissue.

[0045] The user retracts the control member 116 proximally while maintaining distal pressure on the target tissue, thereby drawing the clip arms 106 together as they are retracted into the capsule 112. This causes the distal ends 114 of the clip arms to grasp tissue disposed between them until a point is reached where the clip arms 106 cannot be retracted any further proximally into the capsule. For example, the clip arms 106 in this embodiment include a distal portion 115 that is wider than the proximal portion 109 of the clip arms 106. The narrow proximal portions 109 of the clip arms 106 have a width that allows them to be received within the capsule 112, while the width of the distal portions 115 is greater than can be accommodated within the capsule 112. Thus, as the user pulls the clip arm 106 proximally into the capsule 112 until the proximal end of the distal portion 115 of the clip arm 106 contacts the distal end of the capsule 112, the continued force applied in the proximal direction to the control member 116 increases the tension on the control member 116 and, in turn, the core member 110.

[0046] When the tension reaches a first threshold level, the second break point 168 breaks, separating the distal portion 166 from the intermediate portion of the core member 110. This causes the intermediate portion 162 and the proximal portion 158 of the core member 110 to open and move proximally. As the intermediate portion 162 moves proximally through the open proximal end of the capsule 112, the lateral projections 160 move proximally through the slots 152 such that the angled proximal faces 170 of the lateral projections engage the webs 146, bending them radially outwardly from the recess 142. When the lateral projections 160 contact the closed ends 156 of the slots 152, further proximal movement of the intermediate portion 162 and the lateral projections 160 drives the moving coupling 134 proximally into the distal portion 132.

[0047] As the lateral projections 160 are retracted into the distal portion, the webs 146 are forced radially outward and out of the recesses 142, separating the bushing 128 from the capsule 112. The lateral projections 160 move proximally within the distal portion 132 until they contact a hard stop 176 configured to extend radially inward within the distal portion 132 of the bushing 128 and define the proximal-most point at which the lateral projections and the intermediate portion 162 of the core member 110 may be retracted into the bushing 128.

[0048] Thus, further proximal tension after this point is reached increases the tension applied to the control member 116 and the proximal and intermediate portions 158, 162 of the core member 110, respectively. When a second threshold tension (greater than the first threshold tension) is reached, the first break point 164 breaks and the intermediate portion 162 is separated from the proximal portion 158.

[0049] One skilled in the art will appreciate that in the embodiments described herein, the risk of a lost part is reduced by designing the control member 116 to have sufficient strength to leave the control member 116 intact when the tension required to sever the break point of the core member 110 is reached, so that the control member 116 does not break during deployment of the clip. That is, the core member 110 breaks before the level of tension on the control member 116 reaches a level at which the control member 116 breaks. The distal end of the control member 116 remains coupled to the proximal portion of the control member 116 even after the clip is deployed and is retained within the proximal portion of the core member 110 within the bushing 128 for removal from the body. Because only the distal portion 166 of the core member 110 remains within the capsule 1112, while the intermediate portion 162 and the proximal portion 158 of the core member 110 are each drawn proximally within the bushing 128 for withdrawal from the body, the clip 102 can be made shorter than most conventional clips. For example, clips according to the disclosed embodiments may be as short as 8-9 mm in length (from the distal end 114 of the clip arm 106 to the proximal end of the capsule 112).

[0050] One skilled in the art will appreciate that this action provides a number of instances of feedback to the user. First, the user will appreciate that after opening the clip 102 and closing it on the target tissue, an increase in resistance to further proximal movement of the control member 116 indicates that the distal portion 115 of the clip arm 106 has contacted the distal end of the capsule 112. Then, as increasing tension is applied to the control member 116, the user will feel a release of tension (and hear a click) as the second break point 168 breaks. This informs the user that the clip 102 is clipped and locked onto the target tissue.

[0051] Then, after further proximal movement of the control member 116, the user will feel new resistance to further proximal movement of the control member 116 as the intermediate portion 162 latches into the distal portion 132 of the bushing 128. Finally, after the tension on the control member is increased, the user may feel a release of tension on the control member 116 and hear another click as the first break point 164 breaks. This informs the user that the clip 102 has been successfully clipped on the target tissue and that the clip 102 has separated from the applicator 104. The applicator may then be withdrawn from the insertion instrument, leaving the clip 102 in place within the body.

[0052] 13A, 13B, and 13 show a clipping system 200 according to a further embodiment comprising a clip 202 releasably coupled to an insertion device, such as an applicator 204. The clip 202 includes a pair of clip arms 206 having proximal ends 208 coupled together via a core member 210 that is slidably received within a capsule 212 for operation of the clip 202 between an open configuration in which the distal ends 214 of the clip arms 206 are separated from one another to receive tissue therebetween, and a closed configuration in which the distal ends 214 of the clip arms 206 are drawn together to grasp tissue therebetween.

[0053] The clip arms 206 are actuated between an open configuration and a closed configuration via a control member 216, with a distal end 218 of the control member 216 received within a cavity 220 of the core member 210 while a proximal portion 222 of the control member 216, having a reduced dimension, extends proximally from the cavity 220 and projects out of the core member 210. The proximal portion 222 of the control member 216 extends through the applicator 204 to a proximal end of the system 200 accessible to a user. In this embodiment, the distal end 218 of the control member is enlarged (i.e., has an increased diameter) relative to the proximal portion 222 of the control member 216. The core member 210 includes an opening 219 having a size and shape to allow the distal end 218 to pass therethrough.

[0054] The control member 216 is then rotated such that the distal end 218 is mounted within the cavity 220, which is sized and shaped to snugly receive the distal end 218, as described above with respect to the system 100. In this embodiment, the distal end 218 and the cavity 220 are both substantially cylindrical, with the cavity 220 being slightly larger than the distal end 218 by an allowance to allow the distal end 218 to be securely mounted therein. As seen in FIG. 13B, the longitudinal recess 217 is formed on the side of the core member 210 opposite the side on which the cavity 220 is formed, and extends proximally from the opening 219 such that when the distal end 218 is rotated into position within the cavity 220, the distal-most portion of the proximal portion 222 of the control member 216 is mounted within the longitudinal recess 217. Thus, when the user moves the control member 216 longitudinally (i.e., proximally and distally) relative to the applicator 204, the distal end 218 engages the proximal and distal ends 220p and 220d of the cavity 220, respectively, thereby moving the core member 210 and the clip arms 206 proximally and distally relative to the capsule 212, thereby operating the clip 202 between the open and closed configurations.

[0055] When the clip arms 206 move out of the capsule 212 due to distal movement of the control member 216 relative to the capsule 212, the clip arms 206 spring back apart (e.g., under a natural bias imparted to the clip arms 206). In one embodiment, each of the clip arms 206 is formed from a resilient material, such as Nitinol, and is pre-formed (e.g., thermoformed) into a shape that matches the shape of the clip arms 206 when in the open configuration. Thus, the clip arms 206 spring back apart into the open configuration when not constrained by the capsule 212 to maintain the closed configuration.

[0056] As described in more detail below, clip 202 is releasably coupled to applicator 204 via a bushing 228 coupled to a distal end of applicator 204, such that applicator 204 and bushing 228 form an applicator that is inserted through an insertion instrument (e.g., a flexible endoscope) to a target site within a living body. For example, as shown in FIGURE 15, the portion of applicator 204 extending proximally from bushing 228 to a handle is formed as a coil 205 of flexible material, such as stainless steel, which allows applicator 204 to navigate the tortuous paths traversed by even the most flexible endoscopes.

[0057] The desired orientation of the clip arms 206 within the capsule 212 is maintained in this embodiment by tabs 221 that fold radially inward across the distal opening of the capsule 212 and are received between the clip arms 206. The size of the tabs 221 is selected so that the space allowed for each clip arm 206 at the open distal end of the capsule 212 is sufficient to allow the clip arm 206 to slide in and out of the capsule 212 only when aligned with the tabs 221. The proximal end 208 of each clip arm 206 is coupled to the distal end of the core member 210 via pins 211 that extend radially outward from opposite sides of the core member 210. Each of the pins 211 is threaded through an opening 207 in the proximal end of a corresponding one of the clip arms 206, which causes the clip arms 206 to move proximally and distally within the capsule 212 as the control member 216 moves proximally and distally through the applicator 204. Thus, movement of the control member 216 relative to the applicator 204 moves the clip arms 206 proximally into and distally out of the capsule 212, thereby moving the clip arms 206 between the open and closed configurations. Additionally, the connection between the pins 211 and the clip arms 206 maintains the desired orientation of the core member 210 within the capsule 212, as the clip arms 206 are held in a desired orientation within the capsule 212 by the tabs 221.

[0058] As discussed above, the applicator 204 includes a bushing 228 at its distal end for releasably coupling the applicator 204 to the clip 202. The bushing 228 and its coupling to the capsule 212 are substantially the same as described with respect to the bushing 128 and the capsule 112, and the connection and interaction between the bushing 228 and the core member 210 are also substantially the same as described above with respect to the operation of the core member and the effect on separating the capsule 112 from the bushing 128. As seen in FIG. 14 , the bushing 228 includes a proximal portion 230 having an outer diameter equal to the outer diameter of the distal end of the coil 205, and a distal portion 232 having a reduced outer diameter relative to the proximal portion 230. The outer diameter of the distal portion 232 is equal to the outer diameter of the capsule 212. The bushing 228 includes a moving coupling portion 234 slidably received within the distal portion 232.

[0059] A pair of pins 236 extending radially outward from opposite sides of the moving coupling 234 are received in corresponding slots 238 extending longitudinally through a portion of each of the opposite sides of the distal portion 232, allowing the moving coupling 234 to slide proximally and distally within the distal portion 232 along a distance defined by the slots 238. The moving coupling 234 includes a pair of distally extending wings 240, each of which defines two recesses 242. Each recess 242 is sized and positioned to receive a corresponding locking mechanism in the proximal end 213 of the capsule 212. In this embodiment, the capsule locking mechanism is formed as a series of openings 244 formed between a proximal web 246 and a proximal end 248 of the cylindrical portion of the capsule 212.

[0060] 14, prior to assembly, the proximal end of the capsule 212 is substantially cylindrical, and when the moving coupling 234 is inserted into the capsule 212, the proximal end of the capsule 212 is compressed radially inward, thereby forcing each of the webs 246 into a corresponding one of the recesses 242 and each of the multiple tabs 250 (four tabs 250 in this embodiment) of the moving coupling 234 extending distally of the recesses 242 are received within a corresponding one of the openings 244 to releasably lock the capsule 212 to the bushing 228. The wings 240 of the moving coupling 234 are separated from one another via slots that each extend longitudinally from the open distal end to the closed proximal end, similar to the slots 152 of the bushing 128. In this configuration, the webs 246 extend across the slots 252, similar to that described above with respect to the system 100.

[0061] The core member 210 in this embodiment includes a proximal portion 258 that is connected to a distal portion 262 that extends distally therefrom and is connected to the proximal portion 258 by a break point 264. The proximal portion 258 includes a longitudinal recess 217 with an opening 219 and a cavity 120, while the distal portion 262 includes a pair of diametrically opposed lateral projections 260 that extend outwardly a distance selected to substantially match the inner diameter of the capsule 212 as well as the inner diameter of the distal portion 232 of the bushing 228. The distal portion 262 also includes the pin 211 and two opposed surfaces 268 into which the proximal ends 208 of the clip arms 206 are received.

[0062] The core member 210 and bushing 228 of this embodiment cooperate substantially similarly to the core member 110 and bushing 128 to properly separate the clip 202 from the applicator 204 upon deployment to lock the clip 202 onto the target tissue so that the applicator 204 can be withdrawn from the body while the clip 202 remains clipped in place on the target tissue. Specifically, when the clip 202 is assembled, the core member 210 along with the clip arms 206 are maintained in a desired orientation within the capsule 212 via the tabs 221. In this desired orientation, the distal end of the proximal portion 258, including the lateral projections 260, and the distal portion 262 of the core member 210 are received within the capsule 212, with the lateral projections 260 aligned with slots within the distal portion 232 of the bushing 228.

[0063] As will be appreciated by one skilled in the art, in use, a user advances the clip 202 (e.g., by advancing the applicator 204 and clip 202 through a working channel of a flexible endoscope) to a target site adjacent the target tissue to be clipped. Once the clip 202 is positioned as desired, the user advances the control member 216 distally relative to the applicator 204 to move the core member 210 and clip arms 206 distally through the capsule 212. As the clip arms 206 protrude distally from the capsule 212, the clip arms 206 spread apart under their natural bias into a tissue-receiving open configuration. The clip 202 is then further advanced distally until the distal ends 214 of the clip arms 206 contact the target tissue.

[0064] While maintaining distal pressure on the target tissue, the user retracts the control member 216 proximally, causing the clip arms 206 to be drawn together as they are retracted into the capsule 212. This causes the distal ends 214 of the clip arms 206 to be drawn together to grasp tissue disposed therebetween until a point is reached where the clip arms 206 cannot be retracted any further proximally into the capsule 212. The clip arms 206 in this embodiment include a distal portion 215 that is wider than a proximal portion 231 of the clip arms 206.

[0065] The narrow proximal portions 231 of the clip arms 206 have a width that allows them to be received within the capsule 212, while the width of the distal portions 215 is greater than can be accommodated within the capsule 212. Thus, as a user draws the clip arms 206 proximally into the capsule 212 until the proximal ends of the distal portions 215 of the clip arms 206 contact the distal end of the capsule 212, the continued proximal force applied to the control member 216 increases the tension on the control member 216 and thus the core member 210.

[0066] When the tension reaches a threshold level, break point 264 breaks and separates distal portion 166 from the proximal portion of core member 210. This causes proximal portion 158 of core member 210 to open and move proximally. As the distal end of proximal portion 158 moves proximally through the open proximal end of capsule 212, lateral projections 260 move proximally through slots in the distal portion of distal portion 232 of bushing 228 such that angled proximal surfaces 270 of lateral projections 260 engage webs 246 and bend them radially outward from recess 242.

[0067] When the lateral projection 260 contacts the closed end of the slot in the distal portion 232, further proximal movement of the proximal portion 158 and the lateral projection 260 drives the moving coupling 234 proximally into the distal portion 232. As the lateral projection 260 is drawn into the distal portion 232, which has an inner diameter that substantially matches the radial extent of the lateral projection 260, the web 246 is forced radially outward along the angled surface 270, which moves the web 246 out of the recess 242 and separates the bushing 228 from the capsule 212. The lateral projection 260 is then latched into the distal portion 232 through contact with its inner wall such that further proximal movement of the proximal portion 158 is prevented.

[0068] One skilled in the art will appreciate that this action provides a number of instances of feedback to the user. First, the user will appreciate that after opening the clip 202 to close it on the target tissue, an increase in resistance to further proximal movement of the control member 216 indicates that the distal portion 215 of the clip arm 206 has contacted the distal end of the capsule 212. Then, as increasing tension is applied to the control member 216, the user will feel a release of tension (and hear a click) as the break point 264 breaks. This informs the user that the clip 202 is clipped and locked onto the target tissue. Then, after further proximal movement of the control member 216, the user will feel new resistance to further proximal movement of the control member 216 as the proximal portion 158 latches into the distal portion 232 of the bushing 228. This informs the user that the clip 202 has been successfully clipped onto the target tissue and that the clip 202 has been separated from the applicator 204. The applicator can then be withdrawn from the insertion tool, leaving the clip 202 in place inside the body.

[0069] It is apparent to those skilled in the art that various modifications may be made without departing from the scope of the present disclosure. Although specific embodiments have been illustrated and described herein, any configuration calculated to achieve the same purpose may be substituted for the specific embodiment shown. The present disclosure is intended to encompass any adaptation or modification of the various embodiments. The above description is illustrative and not limiting. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those skilled in the art upon reviewing the above description. Thus, the scope of the various embodiments includes any other applications in which the above compositions, structures, and methods are used.

Claims

1. 1. A clipping system for treating tissue, comprising:

1. An applicator comprising: a flexible elongate member extending from a proximal end that remains outside a living body in use to a distal end that is inserted into said living body in use to a location adjacent a target tissue to be clipped, a control member extending through the applicator; a bushing coupled to a distal end of the flexible elongate member, the bushing including a proximal body portion coupled to the distal end of the flexible elongate member and a distal coupling portion movably attached to the proximal body portion; The applicator comprising: a clip including a capsule and a pair of clip arms, the capsule releasably coupled to the distal coupling portion of the bushing via a first coupling member of the capsule that engages a corresponding first hook of the distal coupling portion of the bushing, the capsule including a channel therethrough, the proximal ends of the pair of clip arms being slidably received within the channel for movement between an open configuration in which the distal ends of the pair of clip arms are separated from one another to receive tissue between the distal ends of the pair of clip arms, and a closed configuration in which the distal ends of the pair of clip arms are drawn toward one another to grasp tissue; a core member received between and connected to the proximal ends of the pair of clip arms, the core member including a first lateral projection and a first break point distal to the first lateral projection; wherein the first break point separates a distal portion of the core member from a proximal portion of the core member, the core member being coupled to a distal end of the control member such that longitudinal movement of the control member relative to the flexible elongate member moves the pair of clip arms between the open and closed configurations, and a lateral extent of the first lateral projection is selected such that when the clip is clipped on a target tissue, the first lateral projection is retracted proximally to move the distal coupling portion into the proximal body portion of the bushing and the first lateral projection can move the first coupling member radially outward beyond an outer end of the first hook to release the capsule from the bushing.

2. 2. The clipping system of claim 1, wherein the core member includes a first pin received within a hole in a proximal portion of a first clip arm of the pair of clip arms and a second pin received within a hole in a proximal portion of a second clip arm of the pair of clip arms.

3. 3. The clipping system of claim 1 or 2, wherein the distal coupling portion is slidably coupled to the proximal body portion of the bushing for proximal and distal movement in and out of the distal end of the proximal body portion.

4. The clipping system of any one of claims 1 to 3, wherein the proximal body portion of the bushing includes a proximal portion having an outer diameter substantially equal to an outer diameter of the flexible elongate member, and a distal portion of the proximal body portion of the bushing has an outer diameter substantially equal to an outer diameter of the capsule.

5. The clipping system of claim 4 , wherein an inner diameter of the channel is substantially equal to an inner diameter of a distal portion of the proximal body portion of the bushing.

6. 6. The clipping system of claim 5, wherein the lateral extent of the first lateral projection is selected to be substantially equal to the inner diameter of the channel and the inner diameter of the distal portion of the proximal body portion of the bushing, and the proximal portion of the distal coupling has an inner diameter slightly smaller than the inner diameter of the channel and the inner diameter of the distal portion of the proximal body portion of the bushing such that the first lateral projection latches against the distal coupling within the bushing.

7. 7. The clipping system of claim 6, wherein the core member includes a second break point proximal to the first break point, the core member defining the distal portion distal to the first break point, an intermediate portion between the first break point and the second break point, and the proximal portion proximal to the second break point.

8. 8. The clipping system of claim 7, wherein the pair of clip arms are configured to define a proximal-most position of the pair of clip arms within the capsule, and when a proximal tension applied to the control member after the pair of clip arms reach the proximal-most position exceeds a first threshold level, the core member separates at the first break point to allow the intermediate portion and the proximal portion of the core member to move proximally thereby drawing the first lateral projection proximally from the capsule and moving the first coupling member of the capsule radially outward beyond an outer end of the first hook of the distal coupling portion of the bushing to separate the capsule from the bushing.

9. 1. An apparatus for clipping tissue, comprising: a bushing including a proximal body portion configured to be coupled to a distal end of a flexible applicator and a distal coupling portion movably attached to the proximal body portion and including a first hook; a clip including a capsule and a pair of clip arms, the capsule releasably coupled to the distal coupling portion via a first coupling member of the capsule that engages the first hook, the capsule including a channel therethrough, the proximal ends of the pair of clip arms being slidably received within the channel for movement between an open configuration in which the distal ends of the pair of clip arms are separated from one another to receive tissue between the distal ends of the pair of clip arms, and a closed configuration in which the distal ends of the pair of clip arms are drawn toward one another to grasp tissue; a core member received between and connected to the proximal ends of the pair of clip arms, the core member including a first lateral projection and a first break point distal to the first lateral projection; wherein the first break point separates a distal portion of the core member from a proximal portion of the core member, the core member being coupled to a distal end of the control member such that longitudinal movement of the control member relative to the flexible applicator moves the pair of clip arms between the open and closed configurations, and a lateral extent of the first lateral projection selected such that when the clip is clipped on a target tissue, the first lateral projection is retracted proximally to move the distal coupling portion into the proximal body portion of the bushing and the first lateral projection can move the first coupling member radially outward beyond an outer end of the first hook to release the capsule from the bushing.

10. 10. The device of claim 9, wherein the core member includes a first pin received within a hole in a proximal portion of a first clip arm of the pair of clip arms and a second pin received within a hole in a proximal portion of a second clip arm of the pair of clip arms.

11. 11. The device of claim 9 or 10, wherein the distal coupling portion is slidably coupled to the proximal body portion of the bushing for proximal and distal movement in and out of a distal end of the proximal body portion.

12. 12. The device of any one of claims 9 to 11, wherein the proximal body portion of the bushing includes a proximal portion having an outer diameter substantially equal to an outer diameter of the flexible applicator, and a distal portion of the proximal body portion of the bushing has an outer diameter substantially equal to an outer diameter of the capsule.

13. The apparatus of claim 12 , wherein an inner diameter of the channel is substantially equal to an inner diameter of a distal portion of the proximal body portion of the bushing.

14. 14. The device of claim 13, wherein the lateral extent of the first lateral projection is selected to be substantially equal to the inner diameter of the channel and the inner diameter of the distal portion of the proximal body portion of the bushing, and the proximal portion of the distal coupling has an inner diameter slightly smaller than the inner diameter of the channel and the inner diameter of the distal portion of the proximal body portion of the bushing such that the first lateral projection latches against the distal coupling within the bushing.

15. 15. The device of claim 14, wherein the core member includes a second break point proximal to the first break point, the core member defining the distal portion distal to the first break point, an intermediate portion between the first break point and the second break point, and the proximal portion proximal to the second break point.

Images