Patent Description:
A surgical fastener deployment device is known from <CIT>, and comprises: a handle; a shaft extending distally from the handle; and a surgical fastener disposed in the shaft, the surgical fastener including a head, and a distally extending coil body attached to the head.

A surgical fastener deployment device according to the present invention is characterised in that the head has a through hole with an internal thread; and the surgical fastener deployment device further comprises a mandrel including a threaded portion, wherein the threaded portion is engaged with the internal thread and the distally extending coil body of the surgical fastener, wherein a pitch of the internal thread of the through hole, and the threaded portion of the mandrel that is engaged with the internal thread, is different from a pitch of the coil body of the surgical fastener, and a rotator associated with the surgical fastener, wherein the rotator rotates the surgical fastener relative to the mandrel to displace the surgical fastener in a distal direction.

The pitch of the coil body of the surgical fastener may be greater than the pitch of the threaded portion of the mandrel.

The pitch of the coil body of the surgical fastener may be less than the pitch of the internal thread of the through hole and of the threaded portion of the mandrel.

The threaded portion of the mandrel and the corresponding internal thread of the surgical fastener may include at least two threads.

The mandrel may be rotationally stationary.

The mandrel may reciprocate in a proximal and distal direction.

The coil body of the surgical fastener may includes at least two separate coil windings that are parallel to each other and extend distally from the head.

An entire length of the coil body located distally from the head may be constructed and arranged to engage with the threaded mandrel.

The coil body of the surgical fastener may be rotationally fixed to the head by a connection between the head and coil body comprising at least one of a compression fit, an adhesive, mechanical interlocking features, and an interference fit.

The mandrel may include a pointed distal tip.

A minimum inner transverse dimension of the coil body of the surgical fastener may be is larger than a maximum transverse dimension of the threaded portion of the mandrel.

Coil fasteners typically do not include a fastener head which may result in the uncovered top coil winding contacting adjacent tissue. Further, in instances where a conventional coil fastener is overdriven, the coil fastener may go through an intended prosthetic material and/or tissue it is meant to engage since there is no structure present to prevent the top coil from passing through the prosthetic material and/or tissue. Consequently, the inventors have recognized the benefits of a fastener including a distally extending coil body including one or more coil windings that is attached to an associated fastener head. Such a fastener offers the benefit of reduced insertion resistance associated with a coil fastener while including a head to avoid the coil body from contacting adjacent tissue and prevent the coil body from passing through the intended prosthetic material and/or tissue. Additionally, the fastener head provides a surface which will abut against a target tissue or prosthetic which may help to prevent overdriving of the surgical fastener through the intended underlying materials.

In embodiments, the surgical fasteners include a distally extending coil body including one or more coil windings attached to a head with a through hole including an internal thread or threads. The coil body may have a cylindrical shape with a circular cross section, though other shapes are possible including a triangular, rectangular, or any other appropriately shaped cross section. One or more of the surgical fasteners may be loaded in a corresponding deployment device. The deployment device includes a stationary or movable mandrel for holding the one or more fasteners. The mandrel also includes an externally threaded portion located at a distal end of the mandrel. The externally threaded portion of the mandrel is constructed and arranged to engage the internal threading of the through hole of the one or more fasteners. To deploy the one or more fasteners, a rotator selectively rotates the one or more fasteners relative to the mandrel. As the one or more fasteners are rotated relative to the mandrel, the threaded portion of mandrel applies a distally directed force to the internal threading of the fastener heads to move the one or more fasteners in a distal direction and sequentially deploy the one or more surgical fasteners into an underlying prosthetic and/or tissue.

For the purposes of this application, a transverse dimension of the coil body or head generally refers to a dimension of the coil body or head within a plane that is perpendicular to a long axis of the surgical fastener when it is assembled (e.g. a diameter of a cylindrical coil body, a width of a rectangular head, the length of a side of a triangular coil body, etc.. For example, an outer transverse dimension of the coil body would refer to the lateral distance between opposing outer surfaces of the coil body and an inner transverse dimension of the coil body would refer to the lateral distance between opposing interior surfaces of the coil body. The outer transverse dimensions of the head TH and coil body Tc in two possible embodiments are illustrated in <FIG> and <FIG> and correspond to the width of the head and the diameter of the coil body. It should be noted that in embodiments in which the head and/or the coil body are noncircular, the head and/or coil body may have both minimum and maximum transverse dimensions.

In view of the above, depending on the particular application, a transverse dimension of the distally extending coil body may be varied to offer different clinical benefits associated with the surgical fastener. For example, in one embodiment, the distally extending coil body has an inner transverse dimension that is approximately the same as a pitch diameter of the threading within the through hole of the fastener head. In such an embodiment, the distally extending coil body engages the corresponding external threading on the mandrel. Further in some embodiments the coil body may extend through the through hole of the fastener head to form the internal threading of the fastener head. In the above embodiment, the coil body is engaged with, and is thus supported by, the mandrel along its entire length which may help to guide and stabilize the coil body of the surgical fastener during deployment. Without wishing to be bound by theory, supporting the coil body during deployment may aid in preventing unwanted buckling or compression of the surgical fastener during deployment. Additionally, a surgical fastener including a coil body with a smaller ratio of coil transverse dimension to fastener head transverse dimension may provide increased mechanical advantage during deployment when a rotator applies a torque to the head of such a surgical fastener.

In another embodiment, a minimum inner transverse dimension of the distally extending coil body is larger than a maximum transverse dimension of the through hole and a maximum outer transverse dimension of the threaded portion of the mandrel. Providing a surgical fastener with a larger minimum coil body transverse dimension allows the surgical fastener to engage larger tissue areas, but the surgical fastener may exhibit decreased mechanical advantage during deployment as compared to the above embodiment because the coil transverse dimension to head transverse dimension ratio is larger. Further, because the distally extending coil bodies have a minimum inner transverse dimension larger than the maximum outer transverse dimension of the threaded portion of the mandrel, they will not be engaged with the mandrel to support the surgical fasteners thereon. Instead, the surgical fasteners are supported on the threaded portion of the mandrel solely by the internal threading located in the through holes of the individual fastener heads. Since the distally extending coil body of the surgical fastener is not supported on the corresponding mandrel, the individual coil bodies may be subject to compression and/or buckling during deployment. Therefore, in some embodiments, it may be desirable to provide one or more guide features associated with the surgical fasteners to avoid buckling and/or compression of the distally extending coil bodiess and ensure proper insertion into tissue during deployment.

It should be understood that the coil bodies and heads of the surgical fasteners may be made from any appropriate materials or combination of materials including various appropriate metals and polymers. Additionally, the material may be selected such that the surgical fastener is non-absorbable or bioabsorable as the current disclosure is not so limited. For example, the distally extending coil body and the head may be made from: stainless steels such as <NUM> stainless steel; nickel titanium based alloys such as nitinol; polypropylene; high density polyurethane; ultrahigh molecular weight polyethylene (UHMWPE); nylon; polyester; magnesium; zinc; polylactic acid; polyglycolic acid; or any other appropriate material.

In addition to the surgical fasteners, the various components of the deployment device, including the mandrel and rotator, may be made from any appropriate material or combination of materials including various appropriate metals and polymers. Appropriate materials include, but are not limited to: stainless steels such as <NUM> stainless steel; nickel titanium based alloys such as nitinol; polypropylene; high density polyurethane; ultrahigh molecular weight polyethylene (UHMWPE); nylon; polyester; or any other appropriate material.

For the sake of clarity, the currently disclosed embodiments are directed to a laparoscopic device. However, the current disclosure is not limited to laparoscopic devices. Instead, the currently disclosed surgical fasteners and associated deployment devices may be used with any appropriate device capable of deploying a fastener into tissue. For example, any of the currently disclosed components, or combination of disclosed components, could be incorporated into an endoscopic device, a borescopic device, a catheter, a surgical instrument for use in "open" procedures, or any other appropriate surgical instrument. Additionally, the deployment device may be loaded with one or more fasteners prior to being provided to an end user, or it may be constructed to allow the user to load one or more fasteners.

Turning now to the figures, specific embodiments of the surgical fasteners and the associated deployment devices are described in more detail. However, it should be understood, that embodiments different from those depicted in the figures are contemplated.

<FIG> depicts a deployment device in the form of a laparoscopic surgical instrument <NUM> for deploying one or more surgical fasteners. The deployment device <NUM> includes a handle <NUM> at a proximal end of the device. The handle includes a trigger <NUM>. The deployment device also includes an outer elongated shaft <NUM> extending in a distal direction from the handle <NUM>. When the trigger <NUM> is actuated, a surgical fastener is deployed from a distal tip of the elongated shaft <NUM>. It should be understood, that the deployed surgical fastener may be deployed into any appropriate prosthetic, bone, and/or tissue. For example, in one embodiment, a surgical fastener can be deployed into a soft tissue repair fabric, such as a surgical mesh, as well as an underlying tissue for repairing a hernia.

<FIG> depicts an exploded view of the deployment device <NUM> of <FIG>. As depicted in the figure, the deployment device includes a mandrel <NUM>, a rotator <NUM>, and an outer elongated shaft <NUM>. The mandrel <NUM> includes a threaded portion <NUM> for supporting one or more surgical fasteners, not depicted. When assembled, the mandrel <NUM> is disposed within the rotator <NUM> which is disposed in the outer elongated shaft <NUM>. The trigger <NUM> is coupled to the rotator <NUM> via a transmission <NUM> such that actuation of the trigger <NUM> rotates the rotator <NUM> relative to the mandrel <NUM>. As described in more detail below, this rotation of the rotator <NUM> relative to the mandrel <NUM> rotates the surgical fasteners disposed on the threaded portion <NUM> of the mandrel, not depicted. Rotation of the surgical fasteners relative to the threaded portion <NUM> of the mandrel displaces the surgical fasteners in a distal direction and deploys a distal most fastener into a prosthetic and/or tissue. It should be understood, that the rotator <NUM> and transmission <NUM> may be embodied in any number of different ways in order to rotate the fasteners relative to the mandrel <NUM>. Therefore, it should be understood, that the current disclosure is not limited to only the rotator <NUM> and transmission <NUM> depicted in the figures and described below.

In one embodiment, the elongated shaft <NUM> is articulable. In such an embodiment, it is desirable that the mandrel <NUM> and the rotator <NUM> be designed to accommodate articulation of the elongated shaft <NUM> while still being capable of deploying a surgical fastener. This may be provided in any number of ways. For example, in one embodiment, rotatable links and/or slots may be provided along a portion of the mandrel and/or rotator length in the articulable portion of the device. Alternatively, the mandrel and/or rotator may be made from a flexible material, or include a flexible material within the articulated portion to permit rotation of the rotator when articulated. In yet another embodiment, the rotator and mandrel may be made from rigid materials located in a rigid distal portion of the elongated shaft that articulates about a joint. A transmission may then be used to transmit power from the trigger and through the articulating joint to deploy a surgical fastener. Other embodiments to permit articulation of the deployment device are also possible. Further embodiments in which the deployment device is not articulable are also possible.

In some embodiments, the mandrel <NUM> is held rotationally and axially stationary relative to the handle <NUM> and/or the outer elongated shaft <NUM>. However, the mandrel <NUM> might also be held rotationally stationary relative to the handle <NUM> and/or outer elongated shaft <NUM> and may be movable in a proximal and distal direction. In such an embodiment, the mandrel <NUM> may advance in a distal direction during deployment of a surgical fastener to extend the mandrel outside of the distal end of the outer elongated shaft <NUM>. The mandrel <NUM> may then retract in a proximal direction after a surgical fastener has been deployed. The mandrel may include either a pointed distal tip <NUM> to aid in positioning the fastener relative to soft and/or hard tissues, or the distal tip <NUM> may be blunt as the current disclosure is not limited in this fashion.

In some embodiments, it may be desirable to increase the deployment and/or retention force of the surgical fasteners relative to the mandrel <NUM>. Consequently, the threaded portion <NUM> of the mandrel and corresponding threading on the surgical fasteners may include multiple threads. For example, the threaded portion <NUM> of the mandrel and the internal threading of the surgical fasteners, not depicted, may include at least two threads, three threads, four threads, or any other desirable number of threads as the current disclosure is not limited in this respect. Without wishing to be bound by theory, in addition to providing increased retention and deployment forces, the multiple threads may also help to stabilize the surgical fasteners on the mandrel as they are distally displaced through the elongated shaft and subsequently deployed into an underlying prosthetic and/or tissue.

Having generally described the various components of the deployment device, <FIG> depicts a close-up exploded perspective view of the distal end of one embodiment of the mandrel <NUM> and the rotator <NUM>. A plurality of surgical fasteners <NUM> are disposed on the threaded portion <NUM> of the mandrel. As depicted in the figures, the surgical fasteners <NUM> include a head <NUM> and a distally extending coil body <NUM> attached to the head. The head <NUM> and distally extending coil body <NUM> of each surgical fastener <NUM> are constructed and arranged to engage with the threaded portion <NUM> of the mandrel. As indicated by the arrow, the mandrel <NUM>, as well as the plurality of surgical fasteners <NUM> disposed thereon, are positioned within the rotator <NUM>. As described in more detail below, the depicted rotator <NUM> is an outer drive cannula with a cross-sectional profile that complements a shape and size of the fastener heads <NUM>. Therefore, rotation of the rotator <NUM> relative to the mandrel rotates the fasteners <NUM> relative to the threaded portion <NUM> of the stationary mandrel. This rotation of the surgical fasteners <NUM> relative to the threaded portion <NUM> of the mandrel, distally displaces the one or more surgical fasteners and deploys a distal most surgical fastener into an underlying prosthetic and/or tissue.

<FIG> depict one embodiment of a surgical fastener <NUM> for use with the deployment device described above. In the depicted embodiment, the surgical fastener <NUM> includes a distally extending coil body <NUM> that is attached to a head <NUM> including a through hole <NUM> with an internal thread. Further, the inner transverse dimension of the distally extending coil body <NUM> is selected such that one or more of the individual coil windings of the distally extending coil body <NUM> engages with the threaded portion of the mandrel along either a portion or substantially the entire length of the coil body <NUM> distally extending from the head <NUM>. In some embodiments, the coil body <NUM> may pass through the through hole <NUM> to form the internal threading located therein. The coil body <NUM> is attached to the head <NUM> using any appropriate method. For example, the coil body <NUM> may be integrally formed with the head <NUM> or it may be manufactured separately and attached using a compression fit, adhesives, mechanical interlocking features, threading, interference fits, or any other appropriate method.

<FIG> depicts an embodiment of a mandrel <NUM> including a threaded portion 12a for use with the surgical fastener depicted in <FIG>. The threaded portion 12a includes a single thread with a different pitch to the coil windings of the coil body <NUM>. Additionally, the threaded portion 12a is sized to engage the internal threading of the through hole <NUM>. While a blunted distal tip <NUM> is depicted, a pointed tip might also be used.

As best shown in <FIG>, the head <NUM> of the surgical fastener has a shape including a series of flats and rounded portions. In order to engage the heads <NUM> of the surgical fasteners, the rotator <NUM>, corresponding to the distally extended elongated outer drive cannula depicted in <FIG>, includes an internal cross-sectional shape that complements the shape and size of the heads <NUM> of the surgical fasteners. The specific shape of the heads <NUM> and the internal cross-section of the rotator <NUM> is selected such that rotation of the rotator <NUM> rotates the fasteners <NUM> relative to the mandrel <NUM> with minimal or no slip. While a specific shape is depicted in the figures, other shapes are also possible. For example, the fastener heads and corresponding cross-sectional shape of the rotator may also correspond to a triangle, a quadrilateral, a pentagon, an asymmetrical shape, or any other appropriate shape capable of transferring rotation of the rotator <NUM> to the fasteners <NUM>. It should be understood that embodiments in which the rotator only complements a portion of the shape and size of the heads also are contemplated.

<FIG> depict various cross-sectional views of the assembled mandrel <NUM>, rotator <NUM>, and a plurality of surgical fasteners <NUM> to help illustrate how the deployment device functions. As illustrated in the figures, the mandrel is disposed inside of the rotator <NUM> with the plurality of surgical fasteners <NUM> disposed thereon. In the depicted embodiment, the heads <NUM> of the surgical fasteners are engaged with the internal cross-section of the rotator <NUM> and the coil windings of the coil body <NUM> are engaged with the thread portion 12a of the mandrel along their entire lengths. During actuation, the rotator <NUM> is rotated relative to the mandrel <NUM>. As the rotator <NUM> is rotated, the internal cross-section of the rotator applies a torque to the head <NUM> of each fastener <NUM>. This torque rotates the fasteners <NUM> relative to the mandrel <NUM>. Due to the internal threading of the coil bodies and/or heads engaging the threaded portion 12a of the mandrel, rotating the heads will apply a distally directed force to the internal threading of the surgical fasteners <NUM> and displace the surgical fasteners <NUM> in a distal direction. As the surgical fasteners <NUM> are displaced in a distal direction, a distal most fastener is displaced out of the distal end of the deployment device and into an underlying prosthetic and/or tissue.

It is beneficial to provide either a compressive or tensile force to a prosthetic and/or tissue that the surgical fastener is deployed into. Therefore, the pitch of the coil windings of the coil body is different from a pitch of the internal threading of the through hole and the associated threaded portion of the mandrel it is engaged with. For example, the coil windings might have a pitch in a relaxed position that is less than a pitch of the internal threading of the through hole and the associated threaded portion of the mandrel. In such an embodiment, the coil body may be deformed to an elongated state while it is positioned on the threaded portion of the mandrel. After the coil body is deployed into tissue, the coil body may contract towards its relaxed position and provide a compressive force to the prosthetic and/or tissue it is deployed into. Similar to the above, in order to provide a tensile force to the prosthetic and/or tissue, the coil windings may have a pitch that is greater than a pitch of the threaded corresponding portion of the mandrel.

<FIG> depict another embodiment of a surgical fastener and an associated deployment device. Similar to the above, the surgical fastener <NUM> includes a distally extending coil body <NUM> attached to a head <NUM> including a threaded through hole <NUM>. However, in this embodiment, an inner transverse dimension of the coil body <NUM> is greater than a transverse dimension of the through hole <NUM> and an associated threaded portion 12b of the mandrel depicted in <FIG>. While the coil body <NUM> may be attached to the head <NUM> in any appropriate fashion, in the depicted embodiment, a proximal end of the coil body <NUM> creates an compression fit with a shoulder <NUM> of the head.

In this embodiment, since the coil body <NUM> is larger than the through hole <NUM> and the associated threaded portion 12b of the mandrel, the coil does not engage the threaded portion 12b of the associated mandrel. Therefore, the surgical fastener <NUM> will be solely supported on the threaded portion of the mandrel by the internal threading located in the through hole <NUM>. In such an embodiment, the internal threading of the through hole <NUM> may include multiple threads to increase the stability of the surgical fastener on the mandrel as well as the force applied during deployment. In the depicted embodiment, the surgical fastener <NUM> includes two internal threads within through hole <NUM>.

To further increase stability and the force applied to the surgical fasteners <NUM> during deployment, it may also be desirable to provide at least a minimum amount of engagement between the internal threading of the through hole <NUM> and the associated threaded portion 12b of the mandrel. For example, a fastener head including a single thread might include at least a full turn of the thread. Similarly, a fastener head including two threads might include at least a half turn of each thread to provide at least a combined full turn of engagement with the multiple threads. It should be understood that other numbers of threads and either greater or lesser amounts of combined thread engagement are also possible.

<FIG> presents an embodiment of a mandrel <NUM> including a threaded portion 12b configured to engage with the internal threading of the through hole <NUM> of the surgical fastener depicted in <FIG>. Since the surgical fastener depicted in the figures has two internal threads, the threaded portion 12b of the mandrel also has two corresponding external threads as well. Additionally, the mandrel <NUM> also includes a pointed distal tip <NUM>. As noted above, the pointed distal tip can be inserted into a prosthetic and/or tissue to aid in positioning the fastener. In such an embodiment, the mandrel <NUM> may either be displaced to extend out of a distal end of an associated deployment device, or it may fixed such that it extends out of the distal end of an associated deployment device. While a pointed distal tip has been depicted with the current embodiment, a blunt tip might also be used.

<FIG> depict the surgical fasteners <NUM> of <FIG> including a coil body that has a larger minimum inner transverse dimension than a maximum outer transverse dimension of the associated through hole and/or threaded portion of the mandrel. To aid in visualization, an associated rotator is not depicted. Similar to the other embodiment described above, the internal threading of the through hole <NUM> of each surgical fastener <NUM> is engaged with the threaded portion 12b of the mandrel. However, as noted above, the distally extending coils <NUM> are not engaged with the threaded portion 12b of the mandrel because it has a larger inner transverse dimension. So, as the surgical fasteners <NUM> are rotated relative to the mandrel <NUM>, the threaded portion 12b of the mandrel will apply a distally directed force to the internal threading located in the through hole <NUM> of each surgical fastener, but will not interact with the distally extending coil bodies directly. Therefore, similar to the other embodiment, this results in the surgical fasteners undergoing both rotation and displacement in a distal direction to deploy the surgical fasteners from the distal end of a deployment device and into a desired prosthetic and/or tissue.

While a particular rotator with a particular cross-sectional shape has been depicted in the figures and described above, it should be understood that any appropriate rotator capable of rotating the surgical fasteners relative to the mandrel may be used. Appropriate rotators may also include: different cross-sectional shapes; distally extending arms that engage corresponding features on the surgical fasteners; a rotator that only engages a portion of the cross-section of the surgical fasteners; keyed features, combinations of the above, and any other appropriate rotator.

In addition to the above, while the depicted surgical fasteners have a fastener head with a particular cross-sectional shape, it should be understood that any appropriate fastener head capable of being engaged by the rotator may be used. For example, other types of features and/or shapes, such as slots, holes, grooves, tabs, and/or combinations of the above, might be used to associate the surgical fasteners with the rotator.

In other embodiments, it may be desirable to increase the retention force of the surgical fasteners in tissue. One possible way in which to do this is to use a coil body including multiple parallel and distally extending coil windings attached to the fastener head. Therefore, in some embodiments, the surgical fasteners may include at least two, three, or any desirable number of parallel and distally extending coil windings attached to the fastener head.

Claim 1:
A surgical fastener deployment device (<NUM>) comprising:
a handle (<NUM>);
a shaft (<NUM>) extending distally from the handle;
a surgical fastener (<NUM>) disposed in the shaft, the surgical fastener including a head (<NUM>), and a distally extending coil body (<NUM>) attached to the head (<NUM>),
characterised in that the head (<NUM>) has a through hole (<NUM>) with an internal thread; and the surgical fastener deployment device further comprises a mandrel (<NUM>) including a threaded portion (<NUM>),
wherein the threaded portion (<NUM>) is engaged with the internal thread of the head (<NUM>) and the distally extending coil body (<NUM>) of the surgical fastener (<NUM>),
wherein a pitch of the internal thread of the through hole (<NUM>), and the threaded portion of the mandrel (<NUM>) that is engaged with the internal thread, is different from a pitch of the coil body (<NUM>) of the surgical fastener (<NUM>), and
a rotator (<NUM>) associated with the surgical fastener (<NUM>), wherein the rotator (<NUM>) rotates the surgical fastener (<NUM>) relative to the mandrel (<NUM>) to displace the surgical fastener (<NUM>) in a distal direction.