Devices and systems for preparing therapeutic pellets

Devices and methods for mixing and preparing therapeutic pellets are described. In one aspect, the present disclosure may include a medical device for mixing and preparing pharmaceuticals. The medical device may include a body sized and shaped to be supported by a human hand. The body may be elastically flexible between a relaxed shape and a flexed shape. In the relaxed shape, the body may form a basin and may be shaped and sized to receive a vessel for mixing or forming the therapeutic pellets. In the flexed shape, the bowl may be configured for controlled pouring of the therapeutic pellets.

FIELD OF THE INVENTION

The invention is related to the field of preparing therapeutic pellets. In particular, therapeutic pellets that may be prepared during orthopedic surgery.

BACKGROUND

Therapeutic pellets may be used during surgery to stabilize the surgical site and/or deliver therapeutics to the surgical site. For example, therapeutic pellets may be used during orthopedic surgery and may provide a scaffold for bone ingrowth, which may include bone growth factors or other characteristics to enhance bone growth. In some cases, the therapeutic pellets may deliver antibiotics to the surgical site to prevent infection. In some applications, the therapeutic pellets may carry bone cements, including calcium-based bone cements such as calcium sulfates and/or calcium phosphates. Such cements may be delivered to a wound or surgical site to facilitate healing, fill bony defects, and/or control infection.

These therapeutic pellets may be created in the operating room during surgery. For example, the surgeon may mix a powder with a liquid to make a paste, form the paste into shapes, often with the help of a mold, and let the paste cure to form hardened pellets. The surgeon may then deliver the pellets to the surgical site. Easing the process of forming the pellets and delivering them to the surgical site can make the surgery go more smoothly. Thus, improved systems for forming and delivering pellets is needed.

BRIEF SUMMARY OF THE INVENTION

The present disclosure provides devices, systems, and methods for forming therapeutic pellets. Therapeutic pellets can be spherical, cylindrical, bullet-shaped, tablet-shaped, or any other suitable shape. In some embodiments, pellets can be formed by providing a portion of the mixed paste and spreading the mixed paste into a flexible mold that has cavities in the desired shape. Once the paste has cured in the mold, the pellets are removed from the mold by flexing the mold and then placed into the patient.

In one aspect of the present disclosure, a medical device for preparation and introduction of therapeutic pellets to a surgical site is provided. The medical device may include a body sized and shaped to be supported by a human hand. The body may be elastically flexible between a relaxed shape and a flexed shape. In the relaxed shape the body may form a basin being shaped and sized to receive a vessel for mixing or forming the therapeutic pellets. In the flexed shape the body may be configured for controlled pouring of the therapeutic pellets.

In some embodiments, the body of the medical device may include a flexible-bowl-shaped body. The flexible bowl-shaped body may include an elastomeric material and may be configured to form a releasable interference fit with an exterior surface of a bowl when the bowl is disposed within the basin. The bowl-shaped body may include a rim along the top of the bowl-shaped body and a recess defined in the bowl-shaped body along a portion of the rim. The bowl-shaped body may be configured to fold inward such that opposing sides of the rim are closer to one another such that the recess forms an opening for dispensing the therapeutic pellets.

In some embodiments, the recess may be configured to form a spout for dispensing the therapeutic pellets when the flexible bowl-shaped body is folded. In some embodiments, the flexible bowl-shaped body may be configured to be folded by one hand of a user. In some embodiments, the bowl-shaped body may further include a second recess defined in the flexible bowl-shaped body along a second portion of the rim opposite the recess. In some embodiments, the flexible bowl-shaped body further include a tab extending from the second recess, where the tab is configured to prevent rotation of the flexible bowl-shaped body relative to the bowl. In some embodiments, the tab may be configured to engage with a corresponding tab in the bowl. In some embodiments, the opening for dispensing the therapeutic pellets may be sized to limit a number of therapeutic pellets that can be poured out of the flexible bowl-shaped body at once.

In one aspect, a kit for therapeutic pellets may be provided. The kit may include a bowl containing a powder material, a liquid container containing liquid configured to mix and react with the powder material to form the therapeutic pellets, and a bowl-shaped body according to one or more of the embodiments of the present disclosure. The bowl-shaped body may be disposed over an exterior surface of the bowl.

In some aspects, the medical device may include a flat surface and two or more raised edges which, together with the flat surface, form the basin. The basin may be configured to receive a flexible mold for forming and curing the therapeutic pellets.

Some embodiments of the present disclosure include a backer board. The backer board may include a flat surface and two or more raised edges extending upward from the flat surface. The backer board may be formed of a first material comprising a first rigidity. The backer board may be shaped to support an elastomeric mold having a second rigidity. The first rigidity of the first material may be greater than the second rigidity of the elastomeric mold. The backer board may be configured to be supportable by one hand of a user.

In some embodiments, the backer board may include a relief configured to facilitate bending of the backer board about the relief. In some embodiments, there may be a first cutout at a corner of the backer board and the relief may be oriented toward the first cutout. In some embodiments, the relief may have a first end disposed proximal to the first cutout and a second end at a side of the backer board. In some embodiments, there may be a second cutout located at the second end of the relief on the side of the backer board. In some embodiments, the relief may be thinner than the flat surface. In some embodiments, the backer board may have a width in the range of 2 to 6 inches and a length in the range of 3 to 12 inches.

In some aspects, a kit for therapeutic pellets may be provided. The kit may include a backer board according to one or more aspects of the present disclosure and an elastomeric mold defining one or more cavities. The backer board may be sized and shaped to receive and support the elastomeric mold.

In some embodiments, the two or more raised edges of the backer board may be configured to fit around a perimeter of the elastomeric mold. In some embodiments, the elastomeric mold may be formed of a silicone rubber and the backer board may be formed of a material that is more rigid that the silicone rubber. In some embodiments, the cavities may be configured to hold a paste during a curing process to form the therapeutic pellets. In some embodiments, the mold may have a first set of cavities and a second set of cavities, where a volume of each cavity in the first set of cavities is greater than a volume of each cavity in the second set of cavities. In some embodiments, the mold comprises a first height at the first set of cavities and a second height at the second set of cavities, where the first height is greater than the second height. The mold may have a first depth for each of the first set of cavities and a second depth for each of the second set of cavities, where the first height is proportional to the first depth and the second height is proportional to the second depth. In some embodiments, the first height may be in a range of 1.25 to 1.75 times the first depth and the second height may be in a range of 1.25 to 1.75 times the second depth.

According to some embodiments of the present invention, a kit for therapeutic pellets may be provided. The kit may comprise a bowl containing a powder material, a liquid container containing liquid configured to mix with the powder material to form the therapeutic pellets, and a flexible cover removably disposed over an exterior surface of the bowl in a manner that allows a user to hold the bowl during mixing by gripping the flexible cover. The flexible cover may be removable from the bowl and flexible to form a pouring spout usable to introduce the therapeutic pellets to a surgical site.

In some embodiments, the kit may further include a relatively more rigid backer board and a relatively less rigid mold having one or more cavities. The backer board may be shaped to support the less rigid mold. In some embodiments, the relatively more rigid backer board may include a relief configured to facilitate bending of the backer board to form a spout.

Some embodiments of the present disclosure may include a method of forming therapeutic pellets. The method may include the steps of: mixing a liquid from a liquid container with a powder material to form a mixture in a bowl having a removable, flexible cover; introducing the mixture to a flexible mold disposed on a backer board to form the therapeutic pellets, wherein the backer board is more rigid than the flexible mold; ejecting the therapeutic pellets from the flexible mold into the backer board; and deforming the backer board to form a spout.

In some embodiments, the method may also comprise the step of delivering the therapeutic pellets from the backer board to a surgical site. The backer board may include a relief to facilitate bending. In some embodiments, the method may also comprise the steps of: removing the flexible cover from the bowl; folding the flexible cover to form a spout for delivering the therapeutic pellets; and delivering the therapeutic pellets from the spout to a surgical site.

Although described with respect to bone cement, it will be understood that the present disclosure contemplates other types of cements, pellets, pastes, and/or materials and applications. For example, the devices and methods described herein may be suitable for forming antibiotic pellets during a curing process to form the therapeutic pellets.

These and other objects, features and advantages of this invention will become apparent from the following detailed description of the various aspects and principles of the invention taken in conjunction with the accompanying drawings.

DETAILED DESCRIPTION

For the purpose of promoting an understanding of the principles of the present disclosure, reference will now be made to the implementations illustrated in the drawings and specific language will be used to describe them. It will nevertheless be understood that no limitation of the scope of the disclosure is intended. Any alterations and further modifications to the described devices, instruments, methods, and any further application of the principles of the present disclosure are fully contemplated as would normally occur to one skilled in the art to which the disclosure relates. In addition, this disclosure describes some elements or features in detail with respect to one or more implementations or figures, when those same elements or features appear in subsequent figures, without such a high level of detail. It is fully contemplated that the features, components, and/or steps described with respect to one or more implementations or figures may be combined with the features, components, and/or steps described with respect to other implementations or figures of the present disclosure. For simplicity, in some instances the same or similar reference numbers are used throughout the drawings to refer to the same or like parts.

As stated above, aspects of the present disclosure include devices, systems, and methods for forming therapeutic pellets. Therapeutic pellets can be formed by providing a portion of the mixed paste and spreading the mixed paste into a flexible mold that has cavities in the desired shape. In some embodiments, the user works the paste into the cavities of the mold, attempting to avoid wasting paste on the top or sides of the mold. Different tools can be used for mixing, spreading, and mold-filling of the paste. Even with these tools, preparing uniform pellets can be difficult, especially if the flexible mold is stretched or deformed while curing. Once the paste has cured in the mold, the pellets are removed from the mold by flexing the mold and then placed into the patient. The devices, systems, and methods described herein advantageously facilitate preparation and delivery of therapeutic pellets.

FIG.1is a perspective view of a kit100for preparing or forming therapeutic pellets, according to an embodiment of the present disclosure. The kit100includes a flexible cover120that fits over a bowl110.FIG.2is an exploded view of the cover120and the bowl110shown inFIG.1. Referring toFIGS.1and2, the flexible cover120may fit snugly over the bowl110such that the flexible cover120forms an interference fit with the bowl110. The bowl110includes threads114to threadably engage with a lid112so that the bowl110can contain one or more of the components of the kit100. In other words, the bowl110may double as packaging for the kit in addition to being used to mix the powder111and liquid130as described in more detail below. In some embodiments, the bowl110includes coupling features other than threads for coupling to the lid112, such as tabs, latches, adhesives, and/or any other suitable coupling feature.

The cover120comprises a flexible material, such as for example only, an elastomeric material such as silicone rubber or a thermoplastic elastomer. These materials may have relatively high coefficients of friction when gripped by a user, enabling them to provide enhanced grip when the cover120is disposed over the bowl110. The flexible material of the cover120may provide a better grip when the user is mixing the components together in the bowl110or scraping the paste out of the bowl. In embodiments where a lid112is included in the kit100, the flexible material of the cover120may make it easier to open the lid112. In some embodiments, the lid112is separate from, but attachable to the bowl110. In some embodiments, the lid112may be hinged or otherwise connected to the bowl110.

In some embodiments, the cover120closely matches the shape or outer profile of the bowl110. By having a close match in shape, the flexible cover120can securely hold the bowl110using friction and/or suction. For example, the flexible cover120may form an interference fit with the bowl110, and may be elastically stretched to receive the bowl therein. The bowl110may include one or more tabs116or slots that engage a pouring recess122formed in the cover120. In the illustrated embodiment, the bowl110has two tabs116that are raised from the surface of the bowl110and there is a space118between the two tabs116. The tabs116engage the sides of the pouring recess122. The tabs116may help resist rotation of the bowl110relative to the cover120.

The bowl110may also have one or more tabs or slots opposing the tabs116for engaging the pouring recess122. These tabs may be configured to engage an opposing recess123of the cover120. The opposing recess123may have a tab124or slot that extends from the recess123to resist the rotation of the bowl110relative to the cover120. In the illustrated embodiment, the bowl110has two tabs116that are raised from the surface of the bowl110. Not shown are two similar tabs116on the opposite side of the bowl. There is a space118between the tabs116for fitting the corresponding tab124of the cover120. The tab124of the cover120may engage the tabs116on the bowl110to prevent rotation of the cover120relative to the bowl110. In some embodiments, the bowl110may include pre-packaged powder111used to form the pellets. The lid112may be affixed to the bowl110to seal the powder111within the bowl110for simple packaging, delivery to, and storage at a use-site, such as a hospital.

In some embodiments, the kit100further includes a liquid130configured to be mixed with the powder111contained in the bowl110to create the pellet material. In some embodiments, the liquid130includes water and the powder111is a calcium-based powder. The liquid130may be mixed with the powder111in the bowl110to form a paste. In some embodiments, the liquid130and powder111may be mixed to form a mixture that is more liquid or more solid than a paste. In some embodiments, the liquid130may include catalysts or retardants that control the speed of the curing of the pellets as discussed in more detail below. The combination of the liquid130and the powder111may be configured to cure and/or harden to form the pellets. As explained below, the paste formed of the powder111and the liquid130can be worked into a flexible mold or mat having cavities that will define the shape of the pellets. In some embodiments, the liquid130is provided in any appropriate container, including, for example, a dropper, a vial, a second bowl with a lid, or any other appropriate container.

The bowl110and the body126of the cover120may be relatively cylindrical having generally straight sides102,104connected to a flat or rounded bottom103,105. The sides102,104and bottom103,105may be connected by rounded edges106,107. The slightly rounded bottom103,105may allow the bowl110and cover120to be placed on a flat surface with minimal wobbling while making it easier for mixing. The rounded edges106,107may also make it easier to mix by preventing the buildup of compacted material in the corners. In some embodiments, the body126of the cover120may be generally semi-spherical. In some embodiments, the bowl110may not be rounded, but may instead be rectangular or cubic. Thus, the cover120may also be rectangular or cubic to match the shape of the bowl110. The bowl110may be any other appropriate shape. For example, the bowl110may be hexagonal, ovate, or triangular. Similarly, the cover120may also be any shape to match the shape of the bowl110, including hexagonal, ovate, or triangular.

In the illustrated embodiment, the width and length of the bowl110are larger than the height. However, the height may be larger than the width and length. In some embodiments, the width and length may be the same or may be different.

FIG.3is a perspective view of the cover120. The cover120may include, or be formed of, a flexible material, such as silicone, rubber, latex, a thermoplastic elastomer, and/or any other suitable type of material. The material of the cover120may be chosen so that the cover120can be folded with pressure or force while maintaining its shape in the absence of a pressure or force. The cover120comprises a bowl-like shape corresponding to the shape of the bowl110. The body126of the cover120has an inner surface127which is configured to contact an outer surface of the bowl110. The shape of the cover120may form a basin that holds the bowl110. There is a rim125along the top of the body126. The cover120includes a pouring recess122formed in the cover120along the rim125, which can aid in the pouring or funneling of the cured pellets into the surgical site, as explained further below. In other embodiments, the cured pellets may be delivered to a wound, and not to a surgical site.

The cover120is flexible such that it may be squeezed, flexed, or folded along an axis to form a lemon-like shape, where the pouring recess122forms an opening on one end of the lemon-like shape of the folded cover120. The pouring recess122is configured to form a spout to provide for a more controlled delivery of the pellets from the cover120. In some embodiments, there may be an extension that extends outward from the bottom of the pouring recess122. When the cover120is folded, the extension may be shaped around to form a spout for the opening formed by the pouring recess122to improve control when pouring pellets out of the cover120. In the illustrated embodiment, the pouring recess122is U-shaped, where the width of the pouring recess122is larger than the height. In some embodiments, the pouring recess122is U-shaped with a height that is larger than the width. In some embodiments, the pouring recess122is V-shaped, rectangular, semi-circular or any other appropriate shape. In some embodiments, the cover120further includes an opposing recess123, which is aligned with the pouring recess122. The folding axis of the cover120may pass through both recesses122,123. Thus, the opposing recess123may allow the cover120to fold more easily.

In some embodiments, the opposing recess123includes a tab124that extends into the open space of the recess123. The tab124may extend from any part of the recess123, including, for example, the bottom of the recess (as illustrated) or the sides of the recess123. As discussed previously, the tab124may align with the tabs116and the opening118of the bowl110so that the cover120is properly aligned with the bowl110and is prevented from rotating relative to the bowl110. In some embodiments, when the cover120is folded in half, the tab124may be configured to increase the size of the opening formed by the pouring recess122. In some embodiments, the tab124may be configured to reduce the size of the opening. In other embodiments, the tab124may be configured so that it does not interfere with the folding of the cover120.

The cover120may be sized and shaped so that it can be held in one hand. For example, the cover may be in the range of 2 to 5 inches wide. Moreover, the flexible material and or the size and shape of the cover120or the parts of the cover may be chosen so that the cover120can be folded easily with one hand. The shape of the cover120may include rounded edges107and a rounded bottom105, which may make it easier to fold the cover120. In some embodiments, the length may be larger than the width, which may also make it easier to fold the cover120. In some embodiments, the cover120may have a uniform thickness. In some embodiments, the cover120may be thicker in certain areas than in other areas. For example, the cover120may have a thicker bottom105. In some embodiments, the sides104of the cover120may be thicker. In some embodiments, a strip of material in the bottom and sides of the cover120may connect the recesses122,123and may be thinner to make it easier to fold the cover120.

The cover120may include more than two recesses or may only include one recess. In some embodiments, there may be more than one tab124in the opposing recess123. In some embodiments, there may be one or more tabs in other recesses. The tabs may be any appropriate shape. For example, the tabs may be rectangular, semispherical, curved, triangular, hexagonal, or any other appropriate shape.

FIGS.4,5, and6are perspective view of a flexible mold140or mat and a backer board150of a pellet preparation system. The pellet preparation system may be included with the kit100shown above inFIGS.1-3. The flexible mold140may include a plurality of cavities141, which may define the shape of the pellets to be formed. In some embodiments, the flexible mold140includes cavities having different shapes and/or sizes. For example, the different-shaped cavities may be selectively used by the physician to form pellets of different shapes depending on the application or the preferences of the physician. In the illustrated embodiment, the mold140has a first142, second143, third144, and fourth145set of cavities. The first142and second143cavities are larger volume than the third144and fourth145set of cavities. Moreover, the first142and second143cavities are arranged width-wise along the mold140whereas the third144and fourth145set of cavities are arranged length-wise. In other embodiments, the mold140may have fewer or more sets of cavities than what is shown inFIG.4. For example, the mold140may have a single set of cavities, two sets of cavities, three sets of cavities, five sets of cavities, and/or any other suitable number of sets of cavities. Each set of cavities may correspond to a different pellet size and/or shape, in some embodiments. In other embodiments, two or more of the sets of cavities may correspond to a same pellet size and/or shape.

FIG.5shows another embodiment of a flexible mold140. In the illustrated embodiment, the mold140may have a first height at a first set146of cavities and a second height at a second set147of cavities. The first and second heights may be different such that the first and second set of cavities form pellets of different volumes. For example, in the illustrated embodiment, the first set146of cavities has a height that is less than the height of the second set147of cavities such that there is a ledge148between the two sets146,147. Moreover, the first set146of cavities has a smaller depth than the second set147of cavities. Thus, the first set146of cavities has a smaller volume than the second set147of cavities. This embodiment is configured such that the first and second set of cavities form pellets of different volumes with different heights. In some aspects, the height of the mold for each set of cavities may correspond to the depth and/or volume of the cavities. The mold140is made of flexible material so that the pellets can be removed easily after they have hardened. The stiffness of the mold140may be related both to the material properties and the geometry of the mold140. Because it can be more difficult to remove a pellet from a very stiff mold140, the mold140may have different heights to adjust the stiffness of the mold140in different areas so that the height is appropriate to eject the size of pellets molded in that area. For example, it may be advantageous that the mold140has a smaller height or thickness for smaller cavities. In this way, the lower rigidity of the mold140may facilitate ejection of the pellets from the mold140. The sets of larger cavity sizes may be in a taller/thicker region of the mold140so that the sets146,147are separated by the ledge148. in some aspects, for pellets with a height of approximately 3/16 inches, the height of the mold140may be in the range of ½ to ⅝ inches. In other embodiments, for pellets with a height of approximately ⅛ inches, the height of the mold140may be in a range of 5/32 to 7/32 inches. In some embodiments, the height of the mold may be in a range of 1.25 to 1.75 times the height of the pellet. In some embodiments, the height of the mold may be in a range of 1.1 to 2 times the height of the pellet. However, the height of the mold and cavities may be any appropriate amount.

In some embodiments, a first set of cavities may be a first shape and a second set of cavities may be a second shape such that pellets of a different shape are formed. The mold140may have any appropriate number of different cavities141with differing sizes and/or shapes.

In some embodiments, the mold140may be manipulated so that pellets from each set of cavities are ejected individually. In some embodiments, the mold140may be manipulated so that all of the pellets may be ejected at the same time.

The flexible mold140may include silicone, rubber, latex, thermoplastic elastomer, and/or any other suitable material. In some embodiments, the flexible mold140comprises the same material as the flexible cover120. In other embodiments, the flexible mold140may include a material that is different from the flexible cover120. As explained further below, the mixed paste can be worked into the cavities of the mold140and left to cure. Once the pellets are cured, the flexible mold140can be flexed, bent, folded, twisted, and/or otherwise manipulated to eject the cured pellets from the flexible mold140.

Referring generally toFIGS.4and6, the backer board150includes a flat surface151and raised edges154around the perimeter of the flat surface151. When the pellets are ejected from the mold140, they may be poured onto the backer board150. The raised edges154may contain the pellets after ejection from the mold140. The flat surface151and raised edges154may form a basin which is shaped to fit the mold140and to hold the pellets when they are ejected from the mold140.

In some embodiments, there is a cutout156or notch at a corner of the backer board150. The edges154of the backer board150may extend to the ends of the cutout156. When the backer board150is folded, the backer board150may function as a funnel, whereby the backer board150can be tilted to direct the pellets toward the cutout156. In some embodiments, the cutout156can be placed, for example, at or near the surgical site to deliver the cured pellets to the surgical site. In other embodiments, the cutout156can direct the cured pellets into the flexible cover120, and the flexible cover120may be used to deliver the pellets to the surgical area. The cutout126is sized and shaped to allow the pellets to be poured out of the backer board150in a controlled manner. In some embodiments, the backer board150may not have a cutout156and instead the pellets may be funneled over the edge154or corner of the backer board150.

In the illustrated embodiment, the backer board150includes four edges154. However, the backer board150may include any appropriate number of edges154. For example, the backer board150may include 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 edges154. The edges154may extend around a majority of the perimeter of the backer board150. In some embodiments, the edges154may not extend around the entire perimeter of the backer board150and there may be gaps between one or more edges154of the backer board150while having an interference fit with the mold140. For example, there may be three edges154that form an interference fit with the mold140.

In some embodiments, the backer board150also includes a relief152or groove formed in the flat surface151. The relief152includes a narrow region of thinned material which allows the backer board to flex, fold, bend, and/or otherwise deform about the relief152. Accordingly, the relief152may improve the function of the backer board150as a funneling or delivery device for the pellets. The relief152may be comprised of the same material as the rest of the backer board150or may be made of a more flexible material. In some embodiments, the relief152may comprise a material that is different from and more flexible than the material of the rest of the backer board150. In some embodiments, the relief152may be the same height as the rest of the flat surface151of the backer board150and may be comprised of the more flexible material. In some embodiments, the relief152may not include a thinned region of material, and rather may be the same thickness as the rest of the backer board150base.

In the embodiment illustrated inFIGS.4and6, the relief152extends from the cutout156towards an opposite edge153of the backer board150without contacting the opposite edge153. However, in some embodiments, the relief152may extend from the cutout156to the opposite edge153as illustrated inFIG.7. In this illustrated embodiment, the backer board150has a second opposing cutout155on the opposite edge153at the end of the relief152. This may allow the backer board150to bend more easily or bend more deeply about the relief152because the opposite edge153does not limit the degree of bending.

In other embodiments, the backer board150may not have a relief152and may include a material that is flexible enough to allow it to bend. In some embodiments, the backer board150may have more than one relief, including, for example, 2, 3, 4, or 5 reliefs.

The backer board150may provide for some rigidity and support for the flexible mold140. For example, a physician may prefer to hold the flexible mold140in her hand while working the paste into the cavities of the flexible mold140. Accordingly, the backer board150provides a flat and rigid rear support for the flexible mold140so that the flexible mold140does not inadvertently flex or move while working the paste into the mold140or while the paste is curing to a hard pellet form. Thus, the backer board150may include a material that is more rigid than the material of the mold140. For example, the backer board150may include polyethylene, ABS (acrylonitrile butadiene styrene), acetal polymer (polyoxymethylene), aluminum alloy, titanium alloy, or steel. In some embodiments, the backer board150may include a material that is more rigid than the material of the mold140, but that is flexible enough so that the backer board150may be bent. For example, it may take 1 inch-pound or more to deflect the backer board1501/100 inches, while the mold140may deflect an inch with 1 inch-pound or less of moment. The backer board150may have a different rigidity along a first axis than along a second axis. For example, the backer board may be more rigid along a longitudinal axis than along an axis coaxial with the relief152.

Additionally, the edges154may provide additional rigidity to the backer board150. The edges154and the flat surface151of the backer board150may include the same material, the material of the edges154may be more rigid than the material of the flat surface151, or the material of the flat surface151may be more rigid than the material of the edges154. The edges154may be thicker, thinner, or the same thickness as the flat surface151.

The edges154may be any appropriate height. The edges154may be the same height or may be different heights. For example, the edges154around the cutouts156,155may be thinner, which may make it easier to bend the backer board150.

In some embodiments, the edges154extend orthogonally from the flat surface151. In some embodiments, the edges154are angled outward or inward from the vertical forming a non-orthogonal angle with the flat surface151. In some embodiments, the edges154may be angled outward from the vertical, which may make it easier to facilitate the insertion and seating of the mold140into the backer board150.

Further, as mentioned above, the backer board150may be used as a temporary container to catch and hold the cured pellets from the flexible mold140. However, in some instances, the physician may eject the cured pellets from the mold140directly into the flexible cover120.

In some embodiments, the backer board150may be sized and shaped so that a user can hold it with one hand. The backer board has a length157and a width158. The dimensions157,158may be any appropriate value, but preferably may be chosen so that the backer board150is easy to handle. For example, the length157may be 4 inches to 12 inches and the width may be 4 inches to 12 inches. In a particular embodiment the length157may be 4 inches and the width158may be 6 inches.

FIG.8is a flow diagram of a method200for preparing therapeutic pellets180in accordance with an embodiment of the present disclosure. The method200may be performed using one or more of the devices, kits, systems, and/or other components described above with respect toFIGS.1-7, for example.FIGS.9A-9Hillustrate various steps of the method200. In some embodiments, the method200may be used to form bone cement pellets180used for one or more therapeutic procedures, including for example, an orthopedic surgery. In some embodiments, the therapeutic pellets180may include or incorporate antibiotic materials to prevent, cure, and/or otherwise control infection in a surgical site. For example, the pellets180may include calcium sulfate and/or calcium phosphate along with vancomycin and/or tobramycin.

Referring toFIG.8, at step210, a pellet preparation kit100is provided. The pellet preparation kit100may include, for example, the bowl110, the cover120, and the liquid130shown inFIG.1above. In some embodiments, the bowl110contains a powder111, such as, for example, calcium sulfate powder. The powder111may come pre-packaged in the bowl110with the lid112closed to simplify the mixing process. The pellet preparation kit100may further include one or more tools, such as spreading tools, mixing tools, and/or any other suitable tool. In some embodiments, step210further includes providing a flexible mold140. The mold140may include one or more cavities141for forming the pellets. Step210may further include providing a backer board150configured to couple to the mold140. The backer board150may be sized and shaped to support and retain the mold140inside the backer board150. In some embodiments, the backer board150may include a flat surface151and raised edges154or side walls around the perimeter of the flat surface151.

Referring toFIGS.8and9A, at step220, a liquid130is introduced into the powder111contained within the bowl110. In this step220, the lid112may be removed from the bowl110to expose the powder111within the bowl110. Then the liquid130may be added to the powder111by pouring or dropping the liquid130into the bowl110. In some embodiments, the liquid130may be a water-based solution, and the powder111may be a calcium-based salt such as calcium sulfate or calcium phosphate. In alternative embodiment, the liquid130may include a monomer liquid, and the powder111may include a copolymer configured to react with the liquid monomer.

Referring toFIGS.8and9B, at step230, the powder111and liquid130are mixed into a paste182within the bowl110. The mixing may be performed using a mixing tool160. The mixing tool160may include a spatula, mixing knife, whisk, and/or any other suitable tool. The mixing may be performed over a period of time. In some aspects, the flexible cover120may provide for improved grip of the bowl110so that the physician or technician can hold both the bowl110in one hand and the mixing tool160in the other hand.

Referring toFIGS.8and9C, at step240, the paste182produced from step230is spread into a flexible mold140. In the illustrated embodiment, the paste182is spread into the mold140using a spreading tool170. The spreading tool170includes a straight, flat surface that can be dragged along the surface of the mold140to work the paste182into the individual cavities of the mold140. In some embodiments, the size (e.g., width, length) of the spreading tool170may correspond to a size (e.g., width, length) of the mold140. Similar to the mixing procedure of step230, the physician may desire to hold the mold140in her hand while spreading the paste into the mold140. Accordingly, a backer board150is provided to support the mold140. The backer board150may include a flat surface that is rigid along at least one axis. Accordingly, the backer board150may prevent the mold140from bending or flexing during the spreading process of step240and during the subsequent curing.

Once the paste182has been removed from the bowl110, the cover120can be removed from the bowl110and set aside. The cover120is now a container ready to hold the cured pellets180. As described in more detail below

To work the paste down to the bottom of the cavities, the mold140and backer board150can be tapped to release any trapped air under the paste and to aid gravity in getting the paste to the bottom of the cavity141. Spreading and tapping can be alternated until the cavities141are properly filled.

Referring toFIG.8, in step250, the pellets are allowed to cure or harden. After the paste is spread into the mold140, the paste may require time to cure or harden. The liquid130and the powder111that are mixed together to form the paste, may be configured to chemically harden or cure over a period of time. Thus, step250includes waiting for the paste to cure or harden so that the pellets180can form. The mold140and backer board150can be set down and the paste182can be left stable until it has completed curing to a hard state. This step250may take any appropriate amount of time, including for example, 1 minute, 4 minutes, 5 minutes, 10 minutes, 30 minutes, 60 minutes, or 90 minutes.

For example, in some embodiments, the curing time may be in a range of 4 minutes to 60 minutes. It may be desirous or beneficial to avoid disturbing the paste182while it is curing in the mold140. Flexing the mold140during the curing process may cause the pellets180to fracture and prevent them from forming into hard, solid pellets180. The backer board150keeps the mold140from flexing. Once the pellets180have cured, the backer board150can be removed from the mold140.

Referring toFIGS.8and9D, at step260, the cured pellets are ejected from the cavities141of the mold140into the backer board150. Step260may include bending, flexing, tapping, stretching, or otherwise manipulating the mold140. The backer board150includes a plurality of raised surfaces or edges154so that when the pellets180are ejected onto the backer board150, the edges154prevent the pellets180from moving off of the backer board150onto other surfaces in the surgical environment. The raised surfaces154may also add stiffness to the backer board150.

Referring toFIG.8, the method200includes two ways in which the surgeon can deliver the pellets180to the surgical site. In steps270and280, the surgeon may use the flexible cover120to deliver the pellets to the surgical site. Alternatively, in step290, the surgeon may use the backer board150itself to deliver the pellets180to the surgical site without using the cover120as an intermediary container.

FIGS.9E-9Hillustrate how the flexible cover120may be used to deliver pellets180to the surgical site according to steps270and280ofFIG.8. In these embodiments, the flexible cover120has been removed from the bowl110.

At step270ofFIG.8, the pellets180are directed from the backer board150into the cover120.FIG.9Eillustrates the same embodiment of the backer board150shown inFIGS.4,6, and9D. In the illustrated embodiment, the backer board150has a cutout156at one corner and a relief152formed in the flat surface151extending from the cutout156towards the opposite edge153of the backer board150across from the cutout156. The relief152may not contact the opposite edge153. However, in some embodiments, the relief152may reach the opposite edge153. The relief152may be an area of thinned material, which makes it easier for the backer board150to bend along the relief152and funnel the pellets180towards the cutout156and into the flexible cover120.

FIG.9Fillustrates another embodiment of the backer board150, which is also illustrated inFIG.7. In this embodiment, the backer board150has a cutout156on the corner of the backer board150and a second opposing cutout155on the opposite edge153from the corner cutout156. There may be a relief152that extends between the cutouts155,156. This embodiment of the backer board150may be easier to bend because there are two cutouts155,156connected by a relief152. By incorporating a second cutout, the backer board150is able to bend more fully because it is not restricted by the opposite edge153. Thus, this embodiment may more easily funnel the pellets180into the flexible cover120.

FIG.9Gillustrates yet another embodiment of the backer board150. In this embodiment, the backer board150has a cutout156on the corner, but does not have a relief152formed in the flat surface151. The backer board150may be configured such that the material and thickness of the backer board150is significantly stiffer than the mold140, but is not too stiff to be manually bent so as to funnel the pellets180towards the cutout156. This embodiment may be easier to manufacture than the backer board150embodiments shown inFIGS.9E and9Fbecause it does not require a relief152or an extra cutout155to be formed.

In any of the embodiments shown or described in reference toFIGS.9E-9G, the backer board150may be held in one hand and may be bent using only that one hand so that the surgeon can easily funnel the pellets180into the cover120. When the backer board150can be handled one-handed, the surgeon has one hand free to hold the cover120or perform another task. In some embodiments, the backer board may require two hands to bend the board, which may cause the board material to yield and permanently deform into the funnel shape.

Referring toFIGS.8and9H, at step280, the cover120is in a folded configuration and is used to funnel pellets180to the surgical site. As described above in reference toFIG.3, the flexible cover120may have pouring recess122and an opposing recess123opposite the pouring recess122. The cover120may be folded along the recesses122,123such that the sides of the rim125come together with the recesses122,123on the ends, forming a lemon-like shape. The pouring recess122may form an opening that the pellets180may be poured or funneled out of into the surgical site. The opposing recess123may help the cover120to bend to improve pouring of the pellets180. The opposing recess123may also include a tab124that extends from the recess123. The tab124, in addition to helping the cover120attach to the bowl110, may prevent the cover120from bending too much. Thus, the tab124may allow the pouring recess122to form a larger opening, which may make it easier for the surgeon to pour out the pellets180to deliver them to the surgical site.

The surgeon may hold the cover120in one hand and may use only that hand to fold the cover120, thus allowing the surgeon to deliver the pellets180to the surgical site with one hand. By allowing the cover120to be handled one handed, the surgeon has one hand free to perform other tasks.

Referring toFIG.8, at step290, instead of delivering the pellets180from the backer board150to the cover120and then to the surgical site, the pellets180may be delivered directly from the backer board150to the surgical site. Any embodiment of the backer board150may be bent as described above in referenceFIGS.9E-9G. However, instead of funneling the pellets180into the cover120, the pellets180are funneled into the surgical site.

Persons of ordinary skill in the art will appreciate that the implementations encompassed by the present disclosure are not limited to the particular exemplary implementations described above. In that regard, although illustrative implementations have been shown and described, a wide range of modification, change, combination, and substitution is contemplated in the foregoing disclosure. It is understood that such variations may be made to the foregoing without departing from the scope of the present disclosure. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the present disclosure.