Patent Description:
Surgical staplers are used in surgical procedures to close openings in tissue, blood vessels, ducts, shunts, or other objects or body parts involved in the particular procedure. The openings can be naturally occurring, such as passageways in blood vessels or an internal organ like the stomach, or they can be formed by the surgeon during a surgical procedure, such as by puncturing tissue or blood vessels to form a bypass or an anastomosis, or by cutting tissue during a stapling procedure.

Most staplers have a handle with an elongate shaft having a pair of movable opposed jaws formed on an end thereof for holding and forming staples therebetween. The staples are typically contained in a staple cartridge, which can house multiple rows of staples and is often disposed in one of the two jaws for ejection of the staples to the surgical site. In use, the jaws are positioned so that the object to be stapled is disposed between the jaws, and staples are ejected and formed when the jaws are closed and the device is actuated. Some staplers include a knife configured to travel between rows of staples in the staple cartridge to longitudinally cut and/or open the stapled tissue between the stapled rows.

While surgical staplers have improved over the years, a number of problems still present themselves. One common problem is that leaks can occur due to the staple forming holes when penetrating the tissue or other object in which it is disposed. Blood, air, gastrointestinal fluids, and other fluids can seep through the openings formed by the staples, even after the staple is fully formed. The tissue being treated can also become inflamed due to the trauma that results from stapling.

Various implantable materials have been developed for use in combination with stapling tissue, however there remains a need for improved materials that address some of the aforementioned problems.

<CIT> describes the use with a staple of a means for compensating for the thickness of the tissue captured within the staples deployed from the staple cartridge. For example, a staple cartridge can include a rigid support portion and a compressible tissue thickness compensator. The tissue thickness compensator may comprise a polymeric composition, such as a biocompatible open cell or closed cell foam. The polymeric composition may comprise one or more of a porous scaffold, a porous matrix, a gel matrix, a hydrogel matrix, a solution matrix, a filamentous matrix, a tubular matrix, a composite matrix, a membranous matrix, a biostable polymer, and a biodegradable polymer, and combinations thereof. A tissue thickness compensator can include a compensator body to be positioned against a cartridge body and, in addition, a plurality of discrete capsules positioned within the compensator body. Each capsule can be positioned between the staple legs of a staple. When the staples are moved from their unfired position to their fired position, the staples can rupture the capsules and thereby release at least one medicament stored therein.

Compressible adjuncts for use with a staple cartridge are provided. According to the invention, a compressible adjunct includes a non-fibrous adjunct material formed of at least one fused bioabsorbable polymer. The adjunct material is configured to be releasably retained on a staple cartridge and is configured to be delivered to tissue by deployment of staples in the cartridge. The adjunct material includes a lattice macrostructure having a plurality of drug delivery microstructures formed in the lattice macrostructure, in which each drug delivery microstructure has drug disposed therein. The plurality of drug delivery microstructures are configured to encapsulate the drug to thereby prevent drug release until the plurality of drug delivery microstructures are thermally ruptured while the adjunct material is stapled to tissue.

The plurality of drug delivery microstructures are configured to thermally rupture in response to an increase in temperature or when the adjunct material is at or above an activation temperature. The increase in temperature can be in response to an infection of the tissue that is stapled to the adjunct material.

The plurality of drug delivery microstructures can have a variety of configurations. The plurality of drug delivery microstructures can include at least one triply periodic minimal surface structure. The plurality of drug delivery microstructures can include at least one Schwarz-P structure. In other cases, the plurality of drug delivery microstructures can include at least one hollow strut.

The lattice macrostructure can have a variety of configurations. The lattice macrostructure can include a plurality of connecting structures. The plurality of connecting structures can extend between and connect adjacent drug delivery microstructures to each other. At least a portion of the plurality of connecting structures can have drug disposed therein.

This invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:.

The devices specifically described herein and illustrated in the accompanying drawings are exemplary, and the scope of the present invention is defined solely by the claims.

To the extent that linear or circular dimensions are used in the description of the disclosed systems and devices, such dimensions are not intended to limit the types of shapes that can be used in conjunction with such systems and devices. Sizes and shapes of the systems and devices, and the components thereof, can depend at least on the anatomy of the subject in which the systems and devices will be used, the size and shape of components with which the systems and devices will be used, and the procedures in which the systems and devices will be used.

It will be appreciated that the terms "proximal" and "distal" are used herein with reference to a user, such as a clinician, gripping a handle of an instrument. Other spatial terms such as "front" and "back" similarly correspond respectively to distal and proximal. It will be further appreciated that for convenience and clarity, spatial terms such as "vertical" and "horizontal" are used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these spatial terms are not intended to be limiting and absolute.

Various exemplary devices are provided for performing surgical procedures. In some cases, the devices are provided for open surgical procedures, and in other cases, the devices are provided for laparoscopic, endoscopic, and other minimally invasive surgical procedures. The devices may be fired directly by a human user or remotely under the direct control of a robot or similar manipulation tool. However, a person skilled in the art will appreciate that the various devices disclosed herein can be used in numerous surgical procedures and applications. Those skilled in the art will further appreciate that the various instruments disclosed herein can be inserted into a body in any way, such as through a natural orifice, through an incision or puncture hole formed in tissue, or through an access device, such as a trocar cannula. For example, the working portions or end effector portions of the instruments can be inserted directly into a patient's body or can be inserted through an access device that has a working channel through which the end effector and elongated shaft of a surgical instrument can be advanced.

It can be desirable to use one or more biologic materials and/or synthetic materials, referred to herein as "adjuncts," in conjunction with surgical instruments to help improve surgical procedures. "Adjuncts" are also referred to herein as "adjunct materials. " While a variety of different surgical end effectors can benefit from the use of adjuncts, the end effector can be a surgical stapler. When used in conjunction with a surgical stapler, the adjunct(s) can be disposed between and/or on jaws of the stapler, incorporated into a staple cartridge disposed in the jaws, or otherwise placed in proximity to the staples. When staples are deployed, the adjunct(s) can remain at the treatment site with the staples, in turn providing a number of benefits. For example, the adjunct(s) may reinforce tissue at the treatment site, preventing tearing or ripping by the staples at the treatment site. Tissue reinforcement may be needed to keep the staples from tearing through the tissue if the tissue is diseased, is healing, and/or is experiencing another tissue property altering situation. In some instances, the adjunct(s) may minimize tissue movement in and around the staple puncture sites that can occur from tissue deformation that occurs after stapling (e.g., lung inflation, gastrointestinal tract distension, etc.). It will be recognized by one skilled in the art that a staple puncture site may serve as a stress concentration and that the size of the hole created by the staple will grow when the tissue around it is placed under tension. Restricting the tissue's movement around these puncture sites can minimize the size the holes may grow to under tension. In some instances, the adjunct(s) can be configured to wick or absorb beneficial fluids, e.g., sealants, blood, glues, and the like, that further promote healing, and in some instances, the adjunct(s) can be configured to degrade to form a gel, e.g., a sealant, that further promotes healing. In some instances, the adjunct(s) can be used to help seal holes formed by staples as they are implanted into tissue, blood vessels, and various other objects or body parts.

In other cases, the adjunct(s) can be used with surgical instruments that are configured to seal tissue without using staples (e.g., by using energy, such as RF or ultrasound), for example, as described in <CIT>.

In some instances, the adjunct(s) can be configured to compensate for variations in tissue thickness when the adjunct(s) are stapled to tissue. In such instances, the adjunct can be also be referred to as a "tissue thickness compensator. " A tissue thickness compensator has an uncompressed (undeformed), or pre-deployed, height that is greater than the height of a staple that is in a formed configuration. Additional details on exemplary tissue thickness compensators can be found in, for example, <CIT>. A tissue thickness compensator can be attached and released from a staple cartridge in a variety of ways, for example, as described in <CIT> and <CIT>.

Additional details pertaining to the adjunct(s) and other exemplary adjuncts can be found in, for example, <CIT> and <CIT>.

Alternatively or in addition, the adjunct(s) can be configured to promote tissue ingrowth. In various instances, it is desirable to promote the ingrowth of tissue into an implantable adjunct, to promote the healing of the treated tissue (e.g., stapled and/or incised tissue), and/or to accelerate the patient's recovery. More specifically, the ingrowth of tissue into an implantable adjunct may reduce the incidence, extent, and/or duration of inflammation at the surgical site. Tissue ingrowth into and/or around the implantable adjunct may, for example, manage the spread of infections at the surgical site. The ingrowth of blood vessels, especially white blood cells, for example, into and/or around the implantable adjunct may fight infections in and/or around the implantable adjunct and the adjacent tissue. Tissue ingrowth may also encourage the acceptance of foreign matter (e.g., the implantable adjunct and the staples) by the patient's body and may reduce the likelihood of the patient's body rejecting the foreign matter. Rejection of foreign matter may cause infection and/or inflammation at the surgical site.

Alternatively or in addition, the adjunct(s) can have medicant(s) thereon and/or therein. The medicant(s) can vary depending on the desired effect of the medicant(s) on the surrounding tissue. As a non-limiting example, medicant(s) can be provided to influence hemostasis, inflammation, macrophages, and/or fibroblasts. Medicant(s) can be mixed or combined in any combination or a medicant can be provided alone, again depending on the desired effect on the tissue. The medicant(s) can be eluted from the adjunct(s) in a variety of different ways. As non-limiting examples, coatings on the adjunct(s) can be varied to be absorbed at different times, thereby releasing the medicant(s) at different times; the adjunct(s) can be varied to allow diffusion of the medicant(s) across the adjunct(s) at varying rates; the adjunct(s) can vary in molecular weight and/or physical characteristics to cause release of the medicant(s) at different times; etc. Additional details on drug eluting adjuncts can be found in <CIT> and <CIT>.

A variety of surgical instruments can be used in conjunction with the adjunct(s) and/or medicant(s) disclosed herein. The surgical instruments can include surgical staplers. A variety of surgical staplers can be used, for example linear surgical staplers and circular staplers. In general, a linear stapler can be configured to create longitudinal staple lines and can include elongate jaws with a cartridge coupled thereto containing longitudinal staple rows. The elongate jaws can include a knife or other cutting element capable of creating a cut between the staple rows along tissue held within the jaws. In general, a circular stapler can be configured to create annular staple lines and can include circular jaws with a cartridge containing annular staple rows. The circular jaws can include a knife or other cutting element capable of creating a cut inside of the rows of staples to define an opening through tissue held within the jaws. The staplers can be used in a variety of different surgical procedures on a variety of tissues in a variety of different surgical procedures, for example in thoracic surgery or in gastric surgery.

<FIG> illustrates one example of a linear surgical stapler <NUM> suitable for use with one or more adjunct(s) and/or medicant(s). The stapler <NUM> generally includes a handle assembly <NUM>, a shaft <NUM> extending distally from a distal end 12d of the handle assembly <NUM>, and an end effector <NUM> at a distal end 14d of the shaft <NUM>. The end effector <NUM> has opposed lower and upper jaws <NUM>, <NUM>, although other types of end effectors can be used with the shaft <NUM>, handle assembly <NUM>, and components associated with the same. The lower jaw <NUM> has a staple channel <NUM> configured to support a staple cartridge <NUM>, and the upper jaw <NUM> has an anvil surface <NUM> that faces the lower jaw <NUM> and that is configured to operate as an anvil to help deploy staples of the staple cartridge <NUM> (the staples are obscured in <FIG> and <FIG>). At least one of the opposed lower and upper jaws <NUM>, <NUM> is moveable relative to the other lower and upper jaws <NUM>, <NUM> to clamp tissue and/or other objects disposed therebetween. In some implementations, one of the opposed lower and upper jaws <NUM>, <NUM> may be fixed or otherwise immovable. In some implementations, both of the opposed lower and upper jaws <NUM>, <NUM> may be movable. Components of a firing system can be configured to pass through at least a portion of the end effector <NUM> to eject the staples into the clamped tissue. In various implementations a knife blade <NUM> or other cutting element can be associated with the firing system to cut tissue during the stapling procedure.

Operation of the end effector <NUM> can begin with input from a user, e.g., a clinician, a surgeon, etc., at the handle assembly <NUM>. The handle assembly <NUM> can have many different configurations designed to manipulate and operate the end effector <NUM> associated therewith. In the illustrated example, the handle assembly <NUM> has a pistol-grip type housing <NUM> with a variety of mechanical and/or electrical components disposed therein to operate various features of the instrument <NUM>. For example, the handle assembly <NUM> can include a rotation knob <NUM> mounted adjacent a distal end 12d thereof which can facilitate rotation of the shaft <NUM> and/or the end effector <NUM> with respect to the handle assembly <NUM> about a longitudinal axis L of the shaft <NUM>. The handle assembly <NUM> can further include clamping components as part of a clamping system actuated by a clamping trigger <NUM> and firing components as part of the firing system that are actuated by a firing trigger <NUM>. The clamping and firing triggers <NUM>, <NUM> can be biased to an open position with respect to a stationary handle <NUM>, for instance by a torsion spring. Movement of the clamping trigger <NUM> toward the stationary handle <NUM> can actuate the clamping system, described below, which can cause the jaws <NUM>, <NUM> to collapse towards each other and to thereby clamp tissue therebetween. Movement of the firing trigger <NUM> can actuate the firing system, described below, which can cause the ejection of staples from the staple cartridge <NUM> disposed therein and/or the advancement the knife blade <NUM> to sever tissue captured between the jaws <NUM>, <NUM>. A person skilled in the art will recognize that various configurations of components for a firing system, mechanical, hydraulic, pneumatic, electromechanical, robotic, or otherwise, can be used to eject staples and/or cut tissue.

As shown in <FIG>, the end effector <NUM> of the illustrated implementation has the lower jaw <NUM> that serves as a cartridge assembly or carrier and the opposed upper jaw <NUM> that serves as an anvil. The staple cartridge <NUM>, having a plurality of staples therein, is supported in a staple tray <NUM>, which in turn is supported within a cartridge channel of the lower jaw <NUM>. The upper jaw <NUM> has a plurality of staple forming pockets (not shown), each of which is positioned above a corresponding staple from the plurality of staples contained within the staple cartridge <NUM>. The upper jaw <NUM> can be connected to the lower jaw <NUM> in a variety of ways, although in the illustrated implementation the upper jaw <NUM> has a proximal pivoting end 34p that is pivotally received within a proximal end 56p of the staple channel <NUM>, just distal to its engagement to the shaft <NUM>. When the upper jaw <NUM> is pivoted downwardly, the upper jaw <NUM> moves the anvil surface <NUM> and the staple forming pockets formed thereon move toward the opposing staple cartridge <NUM>.

Various clamping components can be used to effect opening and closing of the jaws <NUM>, <NUM> to selectively clamp tissue therebetween. As illustrated, the pivoting end 34p of the upper jaw <NUM> includes a closure feature 34c distal to its pivotal attachment with the staple channel <NUM>. Thus, a closure tube <NUM>, whose distal end includes a horseshoe aperture 46a that engages the closure feature 34c, selectively imparts an opening motion to the upper jaw <NUM> during proximal longitudinal motion and a closing motion to the upper jaw <NUM> during distal longitudinal motion of the closure tube <NUM> in response to the clamping trigger <NUM>. As mentioned above, in various implementations, the opening and closure of the end effector <NUM> may be effected by relative motion of the lower jaw <NUM> with respect to the upper jaw <NUM>, relative motion of the upper jaw <NUM> with respect to the lower jaw <NUM>, or by motion of both jaws <NUM>, <NUM> with respect to one another.

The firing components of the illustrated implementation includes a firing bar <NUM>, as shown in <FIG>, having an E-beam <NUM> on a distal end thereof. The firing bar <NUM> is encompassed within the shaft <NUM>, for example in a longitudinal firing bar slot <NUM> of the shaft <NUM>, and guided by a firing motion from the handle <NUM>. Actuation of the firing trigger <NUM> can affect distal motion of the E-beam <NUM> through at least a portion of the end effector <NUM> to thereby cause the firing of staples contained within the staple cartridge <NUM>. As illustrated, guides <NUM> projecting from a distal end of the E-Beam <NUM> can engage a wedge sled <NUM> shown in <FIG>, which in turn can push staple drivers <NUM> upwardly through staple cavities <NUM> formed in the staple cartridge <NUM>. Upward movement of the staple drivers <NUM> applies an upward force on each of the plurality of staples within the cartridge <NUM> to thereby push the staples upwardly against the anvil surface <NUM> of the upper jaw <NUM> and create formed staples.

In addition to causing the firing of staples, the E-beam <NUM> can be configured to facilitate closure of the jaws <NUM>, <NUM>, spacing of the upper jaw <NUM> from the staple cartridge <NUM>, and/or severing of tissue captured between the jaws <NUM>, <NUM>. In particular, a pair of top pins and a pair of bottom pins can engage one or both of the upper and lower jaws <NUM>, <NUM> to compress the jaws <NUM>, <NUM> toward one another as the firing bar <NUM> advances through the end effector <NUM>. Simultaneously, the knife <NUM> extending between the top and bottom pins can be configured to sever tissue captured between the jaws <NUM>, <NUM>.

In use, the surgical stapler <NUM> can be disposed in a cannula or port and disposed at a surgical site. A tissue to be cut and stapled can be placed between the jaws <NUM>, <NUM> of the surgical stapler <NUM>. Features of the stapler <NUM> can be maneuvered as desired by the user to achieve a desired location of the jaws <NUM>,<NUM> at the surgical site and the tissue with respect to the jaws <NUM>, <NUM>. After appropriate positioning has been achieved, the clamping trigger <NUM> can be pulled toward the stationary handle <NUM> to actuate the clamping system. The trigger <NUM> can cause components of the clamping system to operate such that the closure tube <NUM> advances distally through at least a portion of the shaft <NUM> to cause at least one of the jaws <NUM>, <NUM> to collapse towards the other to clamp the tissue disposed therebetween. Thereafter, the trigger <NUM> can be pulled toward the stationary handle <NUM> to cause components of the firing system to operate such that the firing bar <NUM> and/or the E-beam <NUM> are advanced distally through at least a portion of the end effector <NUM> to effect the firing of staples and optionally to sever the tissue captured between the jaws <NUM>, <NUM>.

Another example of a surgical instrument in the form of a linear surgical stapler <NUM> is illustrated in <FIG>. The stapler <NUM> can generally be configured and used similar to the stapler <NUM> of <FIG>. Similar to the surgical instrument <NUM> of <FIG>, the surgical instrument <NUM> includes a handle assembly <NUM> with a shaft <NUM> extending distally therefrom and having an end effector <NUM> on a distal end thereof for treating tissue. Upper and lower jaws <NUM>, <NUM> of the end effector <NUM> can be configured to capture tissue therebetween, staple the tissue by firing of staples from a cartridge <NUM> disposed in the lower jaw <NUM>, and/or to create an incision in the tissue. In this implementation, an attachment portion <NUM> on a proximal end of the shaft <NUM> can be configured to allow for removable attachment of the shaft <NUM> and the end effector <NUM> to the handle assembly <NUM>. In particular, mating features <NUM> of the attachment portion <NUM> can mate to complementary mating features <NUM> of the handle assembly <NUM>. The mating features <NUM>, <NUM> can be configured to couple together via, e.g., a snap fit coupling, a bayonet type coupling, etc., although any number of complementary mating features and any type of coupling can be used to removably couple the shaft <NUM> to the handle assembly <NUM>. Although the entire shaft <NUM> of the illustrated implementation is configured to be detachable from the handle assembly <NUM>, in some implementations, the attachment portion <NUM> can be configured to allow for detachment of only a distal portion of the shaft <NUM>. Detachable coupling of the shaft <NUM> and/or the end effector <NUM> can allow for selective attachment of a desired end effector <NUM> for a particular procedure, and/or for reuse of the handle assembly <NUM> for multiple different procedures.

The handle assembly <NUM> can have one or more features thereon to manipulate and operate the end effector <NUM>. By way of non-limiting example, a rotation knob <NUM> mounted on a distal end of the handle assembly <NUM> can facilitate rotation of the shaft <NUM> and/or the end effector <NUM> with respect to the handle assembly <NUM>. The handle assembly <NUM> can include clamping components as part of a clamping system actuated by a movable trigger <NUM> and firing components as part of a firing system that can also be actuated by the trigger <NUM>. Thus, in some implementations, movement of the trigger <NUM> toward a stationary handle <NUM> through a first range of motion can actuate clamping components to cause the opposed jaws <NUM>, <NUM> to approximate toward one another to a closed position. In some implementations, only one of the opposed jaws <NUM>, <NUM> can move to the jaws <NUM>, <NUM> to the closed position. Further movement of the trigger <NUM> toward the stationary handle <NUM> through a second range of motion can actuate firing components to cause the ejection of the staples from the staple cartridge <NUM> and/or the advancement of a knife or other cutting element (not shown) to sever tissue captured between the jaws <NUM>, <NUM>.

One example of a surgical instrument in the form of a circular surgical stapler <NUM> is illustrated in <FIG>. The stapler <NUM> can generally be configured and used similar to the linear staplers <NUM>, <NUM> of <FIG> and <FIG>, but with some features accommodating its functionality as a circular stapler. Similar to the surgical instruments <NUM>, <NUM>, the surgical instrument <NUM> includes a handle assembly <NUM> with a shaft <NUM> extending distally therefrom and having an end effector <NUM> on a distal end thereof for treating tissue. The end effector <NUM> can include a cartridge assembly <NUM> and an anvil <NUM>, each having a tissue-contacting surface that is substantially circular in shape. The cartridge assembly <NUM> and the anvil <NUM> can be coupled together via a shaft <NUM> extending from the anvil <NUM> to the handle assembly <NUM> of the stapler <NUM>, and manipulating an actuator <NUM> on the handle assembly <NUM> can retract and advance the shaft <NUM> to move the anvil <NUM> relative to the cartridge assembly <NUM>. The anvil <NUM> and cartridge assembly <NUM> can perform various functions and can be configured to capture tissue therebetween, staple the tissue by firing of staples from a cartridge <NUM> of the cartridge assembly <NUM> and/or can create an incision in the tissue. In general, the cartridge assembly <NUM> can house a cartridge containing the staples and can deploy staples against the anvil <NUM> to form a circular pattern of staples, e.g., staple around a circumference of a tubular body organ.

In one implementation, the shaft <NUM> can be formed of first and second portions (not shown) configured to releasably couple together to allow the anvil <NUM> to be detached from the cartridge assembly <NUM>, which may allow greater flexibility in positioning the anvil <NUM> and the cartridge assembly <NUM> in a body of a patient. For example, the first portion of the shaft can be disposed within the cartridge assembly <NUM> and extend distally outside of the cartridge assembly <NUM>, terminating in a distal mating feature. The second portion of the shaft can be disposed within the anvil <NUM> and extend proximally outside of the cartridge assembly <NUM>, terminating in a proximal mating feature. In use, the proximal and distal mating features can be coupled together to allow the anvil <NUM> and cartridge assembly <NUM> to move relative to one another.

The handle assembly <NUM> of the stapler <NUM> can have various actuators disposed thereon that can control movement of the stapler. For example, the handle assembly <NUM> can have a rotation knob <NUM> disposed thereon to facilitate positioning of the end effector <NUM> via rotation, and/or the trigger <NUM> for actuation of the end effector <NUM>. Movement of the trigger <NUM> toward a stationary handle <NUM> through a first range of motion can actuate components of a clamping system to approximate the jaws, e.g., move the anvil <NUM> toward the cartridge assembly <NUM>. Movement of the trigger <NUM> toward the stationary handle <NUM> through a second range of motion can actuate components of a firing system to cause the staples to deploy from the staple cartridge assembly <NUM> and/or cause advancement of a knife to sever tissue captured between the cartridge assembly <NUM> and the anvil <NUM>.

The illustrated examples of surgical stapling instruments <NUM>, <NUM>, and <NUM> provide only a few examples of many different configurations. Although the illustrated examples are all configured for use in minimally invasive procedures, it will be appreciated that instruments configured for use in open surgical procedures, e.g., open linear staplers as described in <CIT>, can also be used. Greater detail on the illustrated examples, as well as additional examples of surgical staplers and components thereof, are provided in <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, and <CIT>.

As indicated above, various implantable adjuncts are provided for use in conjunction with surgical stapling instruments. When used in conjunction with a surgical stapler, the adjunct(s) can be disposed between and/or on jaws of the stapler, incorporated into a staple cartridge disposed in the jaws, or otherwise placed in proximity to the staples. For example, as shown in <FIG>, an adjunct <NUM> is positioned against a staple cartridge <NUM>. For sake of simplicity, the adjunct <NUM> is generally illustrated in <FIG>, and various structural configurations of the adjunct are described in more detail below. While partially obstructed in <FIG>, the staple cartridge <NUM> includes staples <NUM> that are configured to be deployed into tissue. The staples <NUM> can have any suitable unformed (pre-deployed) height. For example, the staples <NUM> can have an unformed height between about <NUM> and <NUM>. Prior to deployment, the crowns of the staples can be supported by staple drivers (not shown).

The adjunct <NUM> can be releasably mated to at least a portion of the top surface or deck surface <NUM> of the staple cartridge <NUM>. The top surface <NUM> of the staple cartridge <NUM> can include one or more surface features. Alternatively, or in addition, one or more adhesives can be used to releasably mate the adjunct to the staple cartridge <NUM>. The one or more surface features and/or the one or more adhesives can be configured to engage the adjunct <NUM> to avoid undesirable movements of the adjunct <NUM> relative to the staple cartridge <NUM> and/or to prevent premature release of the adjunct <NUM> from the staple cartridge <NUM>. Exemplary surface features are described in <CIT>. Additional details on adhesives for temporary attachment to instruments and other exemplary adhesives can be found in <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, and <CIT>. Additional details on attachment procedures can be found in <CIT> and <CIT>.

In certain instances, the adjunct can be compressible to permit the adjunct to compress to varying heights to thereby compensate for different tissue thickness that are captured within a deployed staple. For example, as illustrated in <FIG>, the adjunct <NUM> has an uncompressed (undeformed), or pre-deployed, height and is configured to deform to one of a plurality of compressed (deformed), or deployed, heights. As such, the adjunct <NUM> can have an uncompressed height which is greater than the fired height of the staples <NUM> disposed within the staple cartridge <NUM> (e.g., the height (H) of the fired staple 106a in <FIG>). That is, the adjunct <NUM> can have an undeformed state in which a maximum height of the adjunct <NUM> is greater than a maximum height of a fired staple (e.g., a staple that is in a formed configuration). In such instances, the adjunct can be referred to as a "tissue thickness compensator. " The uncompressed height of the adjunct <NUM> can be about <NUM>% taller, about <NUM>% taller, about <NUM>% taller, about <NUM>% taller, about <NUM>% taller, about <NUM>% taller, about <NUM>% taller, about <NUM>% taller, about <NUM>% taller, or about <NUM>% taller than the fired height of the staples <NUM>. The uncompressed height of the adjunct <NUM> can be over <NUM>% taller than the fired height of the staples <NUM>, for example.

The adjuncts can have a variety of configurations, and can be formed from various materials. In general, an adjunct can be formed from one or more of a film, a foam, an injection molded thermoplastic, a vacuum thermoformed material, a fibrous structure, an additive manufacturing material, and hybrids thereof. The adjunct can also include one or more biologically-derived materials and one or more drugs. Each of these materials is discussed in more detail below.

An adjunct can be formed from a foam, such as a closed-cell foam, an open-cell foam, or a sponge. An example of how such an adjunct can be fabricated is from animal derived collagen, such as porcine tendon, that can then be processed and lyophilized into a foam structure. Examples of various foam adjuncts are further described in previously mentioned <CIT>.

An adjunct can also be formed from a film formed from any suitable material or combination thereof discussed below. The film can include one or more layers, each of which can have different degradation rates. Furthermore, the film can have various regions formed therein, for example, reservoirs that can releasably retain therein one or more medicants in a number of different forms. The reservoirs having at least one medicant disposed therein can be sealed using one or more different coating layers which can include absorbable or non-absorbable polymers. The film can be formed in various ways, for example, it can be an extruded or a compression molded film.

An adjunct can also be formed from injection molded thermoplastic or a vacuum thermoformed material. Examples of various molded adjuncts are further described in <CIT>. The adjunct can also be a fiber-based lattice which can be a woven fabric, knitted fabric or non-woven fabric such as a melt-blown, needle-punched or thermal-constructed loose woven fabric. An adjunct can have multiple regions that can be formed from the same type of lattice or from different types of lattices that can together form the adjunct in a number of different ways. For example, the fibers can be woven, braided, knitted, or otherwise interconnected so as to form a regular or irregular structure. The fibers can be interconnected such that the resulting adjunct is relatively loose. Alternatively, the adjunct can include tightly interconnected fibers. The adjunct can be in a form of a sheet, tube, spiral, or any other structure that can include compliant portions and/or more rigid, reinforcement portions. The adjunct can be configured such that certain regions thereof can have more dense fibers while others have less dense fibers. The fiber density can vary in different directions along one or more dimensions of the adjunct, based on an intended application of the adjunct.

Alternatively, the adjunct can be formed using a 3D printing process(es) compatible with absorbable polymers. Non-limiting examples of suitable 3D printing processes include stereolithography (SLA or SL), material jetting, selective laser sintering (SLS), and fused filament fabrication as understood by a person skilled in the art.

The adjunct can also be a hybrid construct, such as a laminate composite or melt-locked interconnected fiber. Examples of various hybrid construct adjuncts are further described in <CIT>, and in <CIT>.

The adjuncts in accordance with the described techniques can be formed from various materials. The materials can be used for different purposes. The materials can be selected in accordance with a desired therapy to be delivered to tissue so as to facilitate tissue in-growth. The materials described below can be used to form an adjunct in any desired combination.

The materials can include bioabsorbable and biocompatible polymers, including homopolymers and copolymers. Non-limiting examples of homopolymers and copolymers include p-dioxanone (PDO or PDS), polyglycolic acid (PGA) (e.g., Dexon and Neoveil), poly(lactic-co-glycolic acid) (PLGA), polycaprolactone (PCL), polyglycolide (PGL), trimethylene carbonate (TMC), polylactic acid (PLA) (e.g., Linvatec Bioscrew and Bionx Implants Smart Screw), poly(trimethylene carbonate (PTMC), polyethylene diglycolate (PEDG), polypropylene fumarate) (PPF), polyethylene ether (PEE), poly(ethylene glycol) (PEG), poly(N-isopropylacrylamide, poly(amino acid), poly(epoxycarbonate), poly(<NUM>-oxypropylene carbonate), poly(diol citrates), polymethacrylate anhydrides, poly(ethoxyethylene diglycolate), poly(glycolic acid-co-lactic acid) (PLA/PGA) (e.g., PLA/PGA materials used in Vicryl, Vicryl Rapide, PolySorb, and Biofix), polyurethanes (such as Elastane, Biospan, Tecoflex, Bionate, and Pellethane fibers), polyorthoesters, polyanhydrides (e.g., Gliadel and Biodel polymers), polyoxaesters, polyesteramides (e.g., REVA ReZolve Stents), and tyrosine-based polyesteramides (e.g., TYRX). The copolymers can also include poly(lactic acid-co-polycaprolactone) (PLA/PCL) (e.g., <NUM>-<NUM> month hydrolyzed), poly(L-lactic acid-co-polycaprolactone) (PLLA/PCL), poly(glycolic acid-co-trimethylene carbonate) (PGA/TMC) (e.g., Maxon), Poly(glycolic acid-co-caprolactone) (PCL/PGA) (e.g., Monocryl and Capgly), PDS/PGA/TMC (e.g., Biosyn), PDS/PLA, PGA/PCL/TMC/PLA (e.g., Caprosyn), LPLA/DLPLA (e.g., Optima), PLGA-PCL (e.g., <NUM>:<NUM> (PCL: <NUM>% D,L-Lactide: <NUM>% Glycolide), <NUM>:<NUM> (PCL: <NUM>% D,L-Lactide: <NUM>% Glycolide), and <NUM>:<NUM> (PCL: <NUM>% D,L-Lactide: <NUM>% Glycolide), PLGA-PCL-PLGA, and PLGA-PEG-PLGA.

An adjunct can also include special polymer terminations, including (meth)acrylate and organically-derived polymers. Non-limiting examples of organically-derived polymers include those derived from collagen (e.g., Avitene, Endoavitene, Instat, Integran, Veritas, and Microfibrillar Collagen (MFC)).

An adjunct can also include active agents, such as active cell culture (e.g., diced autologous tissue, agents used for stem cell therapy (e.g., Biosutures and Cellerix S. ), hemostatic agents, and tissue healing agents. Non-limiting examples of hemostatic agents can include cellulose such as oxidized Regenerated Cellulose (ORC) (e.g., Surgicel and Interceed), fibrin/thrombin (e.g., Thrombin-JMI, TachoSil, Tiseel, Floseal, Evicel, TachoComb, Vivostat, and Everest), autologous platelet plasma, gelatin (e.g., Gelfilm and Gelfoam), hyaluronic acid such as microfibers (e.g., yarns and textiles) or other structures based on hyaluronic acid, or hyaluronic acid-based hydrogels. The hemostatic agents can also include polymeric sealants such as, for example, bovine serum albumin and glutarldehyde, human serum albumin and polyethylene cross-linker, and ethylene glycol and trimethylene carbonate. The polymeric sealants can include FocalSeal surgical sealant developed by Focal Inc.

The adjuncts described herein can releasably retain therein at least one medicant that can be selected from a large number of different medicants. Medicants include, but are not limited to, drugs or other agents included within, or associated with, the adjunct that have a desired functionality. The medicants include, but are not limited to, for example, antimicrobial agents such as antibacterial and antibiotic agents, antifungal agents, antiviral agents, anti-inflammatory agents, growth factors, analgesics, anesthetics, tissue matrix degeneration inhibitors, anti-cancer agents, hemostatic agents, and other agents that elicit a biological response.

Non-limiting examples of antimicrobial agents include Ionic Silver, Aminoglycosides, Streptomycin, Polypeptides, Bacitracin, Triclosan, Tetracyclines, Doxycycline, Minocycline, Demeclocycline, Tetracycline, Oxytetracycline, Chloramphenicol, Nitrofurans, Furazolidone, Nitrofurantoin, Beta-lactams, Penicillins, Amoxicillin, Amoxicillin + Clavulanic Acid, Azlocillin, Flucloxacillin, Ticarcillin, Piperacillin + tazobactam, Tazocin, Biopiper TZ, Zosyn, Carbapenems, Imipenem, Meropenem, Ertapenem, Doripenem, Biapenem, Panipenem/betamipron, Quinolones, Ciprofloxacin, Enoxacin, Gatifloxacin, Gemifloxacin, Levofloxacin, Lomefloxacin, Moxifloxacin, Nalidixic Acid, Norfloxacin, Sulfonamides, Mafenide, Sulfacetamide, Sulfadiazine, Silver Sulfadiazine, Sulfadimethoxine, Sulfamethizole, Sulfamethoxazole, Sulfasalazine, Sulfisoxazole, Bactrim, Prontosil, Ansamycins, Geldanamycin, Herbimycin, Fidaxomicin, Glycopeptides, Teicoplanin, Vancomycin, Telavancin, Dalbavancin, Oritavancin, Lincosamides, Clindamycin, Lincomycin, Lipopeptide, Daptomycin, Macrolides, Azithromycin, Clarithromycin, Erythromycin, Roxithromycin, Telithromycin, Spiramycin, Oxazolidinones, Linezolid, Aminoglycosides, Amikacin, Gentamicin, Kanamycin, Neomycin, Netilmicin, Tobramycin, Paromycin, Paromomycin, Cephalosporins, Ceftobiprole, Ceftolozane, Cefclidine, Flomoxef, Monobactams, Aztreonam, Colistin, and Polymyxin B.

Non-limiting examples of antifungal agents include Triclosan, Polyenes, Amphotericin B, Candicidin, Filipin, Hamycin, Natamycin, Nystatin, Rimocidin, Azoles, Imidazole, Triazole, Thiazole, Allylamines, Amorolfin, Butenafine, Naftifine, Terbinafine, Echinocandins, Anidulafungin, Caspofungin, Micafungin, Ciclopirox, and Benzoic Acid.

Non-limiting examples of antiviral agents include uncoating inhibitors such as, for example, Amantadine, Rimantadine, Pleconaril; reverse transcriptase inhibitors such as, for example, Acyclovir, Lamivudine, Antisenses, Fomivirsen, Morpholinos, Ribozymes, Rifampicin; and virucidals such as, for example, Cyanovirin-N, Griffithsin, Scytovirin, α-Lauroyl-L-arginine ethyl ester (LAE), and Ionic Silver.

Non-limiting examples of anti-inflammatory agents include non-steroidal anti-inflammatory agents (e.g., Salicylates, Aspirin, Diflunisal, Propionic Acid Derivatives, Ibuprofen, Naproxen, Fenoprofen, and Loxoprofen), acetic acid derivatives (e.g., Tolmetin, Sulindac, and Diclofenac), enolic acid derivatives (e.g., Piroxicam, Meloxicam, Droxicam, and Lornoxicam), anthranilic acid derivatives (e.g., Mefenamic Acid, Meclofenamic Acid, and Flufenamic Acid), selective COX-<NUM> inhibitors (e.g., Celecoxib (Celebrex), Parecoxib, Rofecoxib (Vioxx), Sulfonanilides, Nimesulide, and Clonixin), immune selective anti-inflammatory derivatives, corticosteroids (e.g., Dexamethasone), and iNOS inhibitors.

Non-limiting examples of growth factors include those that are cell signaling molecules that stimulate cell growth, healing, remodeling, proliferation, and differentiation. Exemplary growth factors can be short-ranged (paracrine), long ranged (endocrine), or self-stimulating (autocrine). Further examples of the growth factors include growth hormones (e.g., a recombinant growth factor, Nutropin, Humatrope, Genotropin, Norditropin, Saizen, Omnitrope, and a biosynthetic growth factor), Epidermal Growth Factor (EGF) (e.g., inhibitors, Gefitinib, Erlotinib, Afatinib, and Cetuximab), heparin-binding EGF like growth factors (e.g., Epiregulin, Betacellulin, Amphiregulin, and Epigen), Transforming Growth Factor alpha (TGF-a), Neuroregulin <NUM>-<NUM>, Fibroblast Growth Factors (FGFs) (e.g., FGF1-<NUM>, FGF2, FGF11-<NUM>, FGF18, FGF15/<NUM>, FGF21, FGF23, FGF7 or Keratinocyte Growth Factor (KGF), FGF10 or KGF2, and Phenytoin), Insuline-like Growth Factors (IGFs) (e.g., IGF-<NUM>, IGF-<NUM>, and Platelet Derived Growth Factor (PDGF)), Vascular Endothelial Growth Factors (VEGFs) (e.g., inhibitors, Bevacizumab, Ranibizumab, VEGF-A, VEGF-B, VEGF-C, VEGF-D and Becaplermin).

Additional non-limiting examples of the growth factors include cytokines, such as Granulocyte Macrophage Colony Stimulating Factors (GM-CSFs) (e.g., inhibitors that inhibit inflammatory responses, and GM-CSF that has been manufactured using recombinant DNA technology and via recombinant yeast-derived sources), Granulocyte Colony Stimulating Factors (G-CSFs) (e.g., Filgrastim, Lenograstim, and Neupogen), Tissue Growth Factor Beta (TGF-B), Leptin, and interleukins (ILs) (e.g., IL-1a, IL-1b, Canakinumab, IL-<NUM>, Aldesleukin, Interking, Denileukin Diftitox, IL-<NUM>, IL-<NUM>, IL-<NUM>, IL-<NUM>, IL-<NUM>, and Oprelvekin). The non-limiting examples of the growth factors further include erythropoietin (e.g., Darbepoetin, Epocept, Dynepo, Epomax, NeoRecormon, Silapo, and Retacrit).

Non-limiting examples of analgesics include Narcotics, Opioids, Morphine, Codeine, Oxycodone, Hydrocodone, Buprenorphine, Tramadol, Non-Narcotics, Paracetamol, acetaminophen, NSAIDS, and Flupirtine.

Non-limiting examples of anesthetics include local anesthetics (e.g., Lidocaine, Benzocaine, and Ropivacaine) and general anesthetic.

Non-limiting examples of tissue matrix degradation inhibitors that inhibit the action of metalloproteinases (MMPs) and other proteases include MMP inhibitors (e.g., exogenous MMP inhibitors, hydroxamate-based MMP inhibitors, Batimastat (BB-<NUM>), Ilomastat (GM6001), Marimastat (BB2516), Thiols, Periostat (Doxycycline), Squaric Acid, BB-<NUM>, Hydroxyureas, Hydrazines, Endogenous, Carbamoylphosphates, Beta Lactams, and tissue Inhibitors of MMPs (TIMPs)).

Non-limiting examples of anti-cancer agents include monoclonial antibodies, bevacizumab (Avastin), cellular/chemoattractants, alkylating agents (e.g., Bifunctional, Cyclophosphamide, Mechlorethamine, Chlorambucil, Melphalan, Monofunctional, Nitrosoureas and Temozolomide), anthracyclines (e.g., Daunorubicin, Doxorubicin, Epirubicin, Idarubicin, Mitoxantrone, and Valrubicin), cytoskeletal disrupters (e.g., Paclitaxel and Docetaxel), epothilone agents that limit cell division by inhibiting microtubule function, inhibitor agents that block various enzymes needed for cell division or certain cell functions, histone deacetylase inhibitors (e.g., Vorinostat and Romidepsin), topoisomerase I inhibitors (e.g., Irinotecan and Topotecan), topoisomerase II inhibitors (e.g., Etoposide, Teniposide, and Tafluposide), kinase inhibitors (e.g., Bortezomib, Erlotinib, Gefitinib, Imatinib, Vemurafenib, and Vismodegib), nucleotide analogs (e.g., Azacitidine, Azathioprine, Capecitabine, Cytarabine, Doxifluridine, Fluorouracil, <NUM>-FU, Adrucil, Carac, Efudix, Efudex, Fluoroplex, Gemcitabine, Hydroxyurea, Mercaptopurine, and Tioguanine), peptide antibiotic agents that cleave DNA and disrupt DNA unwinding/winding (e.g., Bleomycin and Actinomycin), platinum-based anti-neoplastic agents that cross link DNA which inhibits DNA repair and/or synthesis (e.g., Carboplatin, Cisplatin, Oxaliplatin, and Eloxatin), retinoids (e.g., Tretinoin, Alitretinoin, and Bexarotene), vinca alkaloids agents that inhibit mitosis and microtubule formation (e.g., Vinblastine, Vincristine, Vindesine, Vinorelbine), angiostatic inhibiting agents that inhibit cell growths or cell expansion (e.g., Axitinib (Inlyta), Bevacizumab (Avastin), Cabozantinib (Cometriq), Everolimus (Afinitor, Zortress) Lenalidomide (Revlimid), Pazopanib (Votrient), Ramucirumab (Cyramza), Regorafenib (Stivarga), Sorafenib (Nexavar), Sunitinib (Sutent), Thalidomide (Synovir, Thalomid), Vandetanib (Caprelsa), Zib-aflibercept (Zaltrap), antiangiogenic polysaccharide, aplidine (dehydrodidemnin B), sapogenins viz. <NUM>(S)-protopanaxadiol, and <NUM>(S)-protopanaxatriol), anti-ileus agents, pro-motility agents, immunosuppresants (e.g., Tacrolimus), blood aspect modifier agents (e.g., Vasodilator, Viagra, and Nifedipine), <NUM>-hydroxy-<NUM>-methylglutaryl-CoA (HMG CoA) reductase inhibitors (e.g., Atorvastatin), and anti-angiogenesis agents.

Exemplary medicants also include agents that passively contribute to wound healing such as, for example, nutrients, oxygen expelling agents, amino acids, collageno synthetic agents, Glutamine, Insulin, Butyrate, and Dextran. Exemplary medicants also include anti-adhesion agents, non-limiting examples of which include Hyaluronic acid/ Carboxymethyl cellulose (seprafilm), Oxidized Regenerated Cellulose (Interceed), and Icodextrin <NUM>% (Extraneal, Adept).

Exemplary medicants also include agents that encourage blood supply regeneration following coronary artery disease (CAD) (e.g., VEGF<NUM> protein, AdVEGF<NUM>, AdVEGF<NUM>, and VEGF<NUM> plasmid) or periphery artery disease (PAD) (e.g., VEGF<NUM> plasmid, AdVEGF<NUM>, SB-<NUM> (SFP-VEGF plasmid), AdVEGF<NUM>, and Ad2-HIF1α-VP16 (WALK trial)).

An adjunct in accordance with the described techniques can be associated with at least one medicant in a number of different ways, so as to provide a desired effect, such as on tissue in-growth, in a desired manner. The at least one medicant can be configured to be released from the adjunct in multiple spatial and temporal patterns to trigger a desired healing process at a treatment site. The medicant can be disposed within, bonded to, incorporated within, dispersed within, or otherwise associated with the adjunct. For example, the adjunct can have one or more regions releasably retaining therein one or more different medicants. The regions can be distinct reservoirs of various sizes and shapes and retaining medicants therein in various ways, or other distinct or continuous regions within the adjuncts. In some aspects, a specific configuration of the adjunct allows it to releasably retain therein a medicant or more than one different medicant.

Regardless of the way in which the medicant is disposed within the adjunct, an effective amount of the at least one medicant can be encapsulated within a vessel, such as a pellet which can be in the form of microcapsules, microbeads, or any other vessel. The vessels can be formed from a bioabsorbable polymer.

Targeted delivery and release of at least one medicant from an adjunct can be accomplished in a number of ways which depend on various factors. In general, the at least one medicant can be released from the adjunct material as a bolus dose such that the medicant is released substantially immediately upon delivery of the adjunct material to tissue. Alternatively, the at least one medicant can be released from the adjunct over a certain duration of time, which can be minutes, hours, days, or more. A rate of the timed release and an amount of the medicant being released can depend on various factors, such as a degradation rate of a region from which the medicant is being released, a degradation rate of one or more coatings or other structures used to retains the medicant within the adjuncts, environmental conditions at a treatment site, and various other factors. In some aspects, when the adjunct has more than one medicant disposed therein, a bolus dose release of a first medicant can regulate a release of a second medicant that commences release after the first medicant is released. The adjunct can include multiple medicants, each of which can affect the release of one or more other medicants in any suitable way.

Release of at least one medicant as a bolus dose or as a timed release can occur or begin either substantially immediately upon delivery of the adjunct material to tissue, or it can be delayed until a predetermined time. The delay can depend on a structure and properties of the adjunct or one or more of its regions.

An adjunct material can be configured to have a structure that facilitates distribution of effective amounts of one or more medicants carried within the adjunct to provide a desired effect. For example, the targeted delivery of the medicants can be accomplished by incorporating the medicants into regions (e.g., reservoirs such as pores or other structures) within the adjunct formed in a pattern that allows a certain spatial distribution of the medicants upon their delivery. The medicants disposed within the reservoir can be incorporated into distinct vessels. A reservoir can include more than one type of different medicants. The one or more medicants can be eluted from the adjunct in a homogeneous manner or in heterogeneous spatial and/or temporal manner to deliver a desired therapy. The structure of the adjunct and the way in which the medicants are released therefrom can be used to influence or control tissue re-growth. Moreover, the tissue regrowth can be encouraged in certain locations at the treatment site and discouraged at other locations at the treatment site.

The adjuncts can have configurations designed to control drug movement though and out of the adjuncts when the adjuncts are in a tissue deployed state (e.g., stapled to tissue in vivo). As discussed below, the adjuncts can include active drug release features that are designed to effect drug release from the adjuncts in a controlled and tailored manner when such features are thermally activated. That is, unless activated, the active drug release features are configured to encapsulate the drug and therefore inhibit drug from being released from the adjunct. In this way, the active drug release features can help prevent premature drug release from the adjuncts.

The adjuncts can generally be formed at least one fused bioabsorbable polymer that is configured to be releasably retained on a staple cartridge and that is configured to be delivered to tissue by deployment of staples in the cartridge. For exemple, the adjunct material can include a lattice macrostructure having drug delivery microstructures formed in the lattice macrostructure, and each drug delivery microstructure can have drug disposed therein. The drug delivery microstructures can be configured to encapsulate the drug to thereby prevent drug release until the plurality of drug delivery microstructures are thermally ruptured in response to changes in body temperature. The drug delivery microstructures can have an internal cavity (e.g., microreservoir) defined therein. As used herein, the term "lattice macrostructure" is used synonymously with the term "lattice main structure.

In order to enable formation of macro and micro structures, the adjuncts can be non-fibrous adjuncts. Unlike conventional adjuncts (e.g., adjuncts that are not three-dimensionally printed, such as foam adjuncts and woven/non-woven fibrous adjuncts), the non-fibrous adjuncts are three-dimensionally (3D) printed and therefore can be formed with microstructures (units) that are consistent and reproducible. That is, unlike with other methods of manufacture, 3D printing significantly improves control over microstructural features such as placement and connection of elements. As a result, variability in both the microstructure(s) and attendant properties of the present adjuncts is decreased, as compared to conventional adjuncts. Further, 3D printing can create adjuncts with microstructural features that could not otherwise be formed or generated within conventional adjuncts. The present non-fibrous adjuncts can also be adapted for use with a variety of staples and tissue types.

The drug delivery microstructures are configured to thermally rupture in response to an increase in temperature.

The increase in temperature can be in response to an infection of the stapled tissue. That is, once the adjunct is in a tissue deployed state (e.g., stapled to tissue in vivo), the temperature at or proximate to the stapled adjunct can increase due to infected tissue (e.g., due to swelling and/or localized increased in blood flow). As a result, this increase in temperature can initiate the release of the drug from one or more of the drug delivery microstructures. For example, the drug delivery microstructures can be in the form of microcontainers that are sealed with a material that is configured to break down or liquefy at an elevated body temperature (e.g., greater than about <NUM>). Once the microcontainers are unsealed, the drug can be released out of the adjunct, and the drug (e.g., antibiotic(s)) can be used to treat the infection. In certain cases, the microcontainers are sealed with a plug that is formed of the material. Alternatively, or in addition, where the initial release of the drug one or more drug delivery microstructures are already thermally ruptured, the temperature increase can be used to accelerate the release of the drug from the drug delivery microstructures.

The drug delivery microstructures can be configured to thermally rupture when the adjunct material is at or above an activation temperature. The activation temperature can be associated with body temperature (e.g., about <NUM>). As a result, the body temperature can be used as a gating key that can initiate the release of the drug from one or more of the drug delivery microstructures. For example, the drug delivery microstructures can be in the form of microcontainers that are sealed with a material that is configured to break down or liquefy when exposed to body temperature or body temperature in the presence of humidity. The microcontainers can be sealed with a plug that is formed of the material. In other cases, the drug delivery microstructures can be formed of a structure (e.g., formed of a shape memory material) having initially sealed pores, and once the adjunct is in a tissue deployed state, the exposure to body temperature can cause the sealed pores to open and release drug therefrom.

Daily temperature variation at or proximate to the stapled tissue can be used to control the rate of drug release from the drug delivery microstructures. For example, a combination of time and temperature dependent release features could allow the administration of drug to the patient over multiple days at approximately the same time. Temperature activated release feature(s) can be encapsulated in different thicknesses of time dependent release materials. Alternatively, the drug delivery microstructures can be in the form of microcontainers that are sealed with a different material(s) or material thicknesses that are configured to release at body temperature. These microcontainers can be sealed with plugs having different thicknesses and/or formed of different materials relative to each other. First microcontainers can be sealed with first plugs and second microcontainers can be sealed with second plugs that differ from the first plugs in material and/or thickness.

The drug delivery microstructures can have a variety of configurations. The drug delivery microstructures can be strut-based unit cells characterized by the presence of sharp corners or angles, non-strut-based unit cells characterized by curved surface, or a combination thereof. With non-strut based unit cells, the unit cells, for example, can be based on triply periodic minimal surfaces (TPMS). TPMS is a minimal surface that repeats itself in three dimensions. The term "minimal surface" as used in this description refers to a minimal surface as known in mathematics. Thus, the unit cell can be a triply periodic minimal surface structure (e.g., Schwarz-P, Schwarz Diamond, and the like) having passageways extending therethrough. For example, the non-strut based unit cells can be a hollow structure. The lattice main structure can include a combination of strut-based unit cells (e.g., hollow struts) and non-strut based unit cells (e.g., one or more triply periodic minimal surface structures). The non-strut based unit cells can be interconnected to each other via connecting structures. These connecting structures can take the form of hollow tubes or struts. The unit cell(s) can include the connecting structures.

Each exemplary adjunct as described below is illustrated in partial form (e.g., not in full-length), and therefore a person skilled in the art will appreciate that the adjunct can be longer in length, e.g., along its longitudinal axis (LA). The length can vary based on a length of the staple cartridge or anvil. The width can also vary as needed. Further, each exemplary adjunct is configured to be positioned atop a cartridge or anvil surface such that the longitudinal axis L of each adjunct is aligned with and extends along the longitudinal axis (LA) of the cartridge or anvil. These adjuncts are structured so as to compress when exposed to compressive forces (e.g., stress or load).

Claim 1:
A compressible adjunct (<NUM>) for use with a staple cartridge (<NUM>, <NUM>, <NUM>), the compressible adjunct (<NUM>) comprising:
a non-fibrous adjunct material formed of at least one fused bioabsorbable polymer and configured to be releasably retained on a staple cartridge (<NUM>, <NUM>, <NUM>) and configured to be delivered to tissue by deployment of staples (<NUM>) in the cartridge (<NUM>, <NUM>, <NUM>), the adjunct material (<NUM>) comprising a lattice macrostructure having a plurality of drug delivery microstructures formed in the lattice macrostructure, each drug delivery microstructure having drug disposed therein, wherein the plurality of drug delivery microstructures are configured to encapsulate the drug to thereby prevent drug release until the plurality of drug delivery microstructures are ruptured;
characterized in that the plurality of drug delivery microstructures are configured to thermally rupture while the adjunct material (<NUM>) is stapled to tissue, in response to an increase in temperature or when the adjunct material is at or above an activation temperature.