Device and method for preparing a bone cement dough

Description

[0001] The invention relates to a device for providing a bone cement dough from two starting components, comprising a mixing unit comprising a hollow cylindrical cartridge with an interior space, wherein a discharge piston which is axially movable in the interior space and divides the interior space into a proximal part of the interior space and a distal part of the interior space, wherein the proximal part and the distal part of the interior space are fluidly connected to one another via a conduit, wherein a bone cement powder is stored as the first starting component in the proximal part of the interior space and wherein a delivery piston which is axially movable in the interior space is arranged in the distal part of the interior space, and a reservoir for a monomer liquid as the second starting component, which reservoir is or can be fluidly connected via an inlet channel to the distal part of the interior space for introducing the monomer liquid from the reservoir into the mixing unit.

[0002] The invention further relates to a method for providing a bone cement dough from two starting components by means of such a device. Background of the invention

[0003] Considerable efforts are being made to develop devices and methods for providing bone cement that allow for simple, reliable, and rapid preparation. An important aspect of bone cement preparation is the avoidance of air inclusions, such as gas bubbles, in the bone cement. To avoid this, a variety of vacuum cementing systems have been described, of which the following are examples: US 6,033,105 A, US 5,624,184 A, US 4,671,263 A, US 4,973,168 A, US 5,100,241 A, WO 99 / 67015 A1, EP 1020167 A2, US 5,586,821 A, EP 1016452 A2, DE 3640279 A1, WO 94 / 26403 A1, EP 1005901 A2, EP 1886647 A1, US 5,344,232 A.

[0004] There is a desire in the market to simplify the preparation of bone cement dough. One further development is the development of cementing systems in which both starting components are stored in separate areas of the mixing systems and are only mixed together in the cementing system immediately before cementing application.

[0005] Such closed, so-called fully prepacked systems are mentioned, for example, in the following documents: EP 0 692 229 A1, DE 10 2009 031 178 B3, US 5,997,544 A, US 6,709,149 B1, DE 698 12 726 T2, EP 0 796 653 A2, US 5,588,745 A.

[0006] In the aforementioned fully prepacked systems, a monomer liquid is mixed with a bone cement powder by mechanical mixing, for example using a mixing rod.

[0007] In contrast to the aforementioned fully prepacked systems, patent EP 3 320 870 B1 describes a device in which the mixing of a monomer liquid with a bone cement powder occurs simply by pressing the monomer liquid into, in particular, compacted, bone cement powder. The described device therefore does not require mechanical mixing, in particular a mixing rod. Such devices are therefore designed without any mixing device.

[0008] In the device, a container filled with monomer liquid is mounted axially behind a region within a cartridge filled with bone cement powder. A dispensing piston is arranged between the bone cement powder and the container. To provide a bone cement paste, a delivery piston, which is arranged on a side of the container opposite the dispensing piston, is driven towards the dispensing piston, causing the container to open, in particular by partially bursting a container in the form of a glass ampoule into container pieces. The monomer liquid emerging from the container is conveyed into the bone cement powder by the continued advance of the delivery piston, forming the bone cement paste.

[0009] Comparable devices are also described in the patents EP 3 320 869 B1 and EP 3 403 716 B1.

[0010] A disadvantage of these devices is that in order to open and convey the monomer liquid into the bone cement powder, the container must be essentially completely destroyed, which on the one hand requires a comparatively high level of force from a user of the device and on the other hand makes it difficult to convey the monomer liquid essentially completely into the bone cement powder, in particular due to the fragments of the container.

[0011] Patent application EP 3 838 391 A1 also describes a device for preparing a bone cement dough without a mixing device.

[0012] In this device, a container filled with a monomer liquid is stored in a reservoir. After the container is opened, the monomer liquid can flow via a conduit into a distal part of an interior space before being pumped into a bone cement powder in a proximal part of the interior space by advancing a piston. The reservoir is arranged such that the container is neither opened by the piston nor compressed when the monomer liquid is pumped into the bone cement powder.

[0013] A disadvantage of this device is that the monomer liquid can only flow slowly and / or intermittently through the conduit into the distal part of the interior space, as the diameter of the conduit must be designed such that the container, or parts of it, cannot pass through the conduit into the interior space. Furthermore, it is difficult for gas to be displaced from the interior space by the monomer liquid flowing into it to be discharged through the conduit. The conduit is therefore not designed for good mass transfer between the reservoir and the interior space. This is a disadvantage because, particularly in time-critical operations, a rapid, safe and essentially complete supply of the monomer liquid for mixing the bone cement dough is necessary. A further disadvantage of the device is its relatively complex design with many moving components.In addition, the piston, which was already used to pump the monomer liquid into the bone cement powder, is not designed to discharge the bone cement paste from the device. In particular, the reservoir protruding from the device would make discharging the bone cement paste from the device difficult for steric reasons.

[0014] There is therefore a desire in the market to further simplify devices for providing bone cement dough.

[0015] EP 3 643 398 A1 discloses a device for providing a bone cement dough according to the preambles of claims 1, 2. Tasks

[0016] An object of the present invention is to at least partially overcome one or more of the disadvantages resulting from the prior art.

[0017] Specifically, the invention is based on the objective of providing a device that allows for simple and safe opening of one or more ampoules, particularly glass ampoules, containing a monomer liquid for the simple, rapid, and safe preparation of a bone cement paste. In particular, the ampoule or ampoules should be opened with as little effort as possible and without the need for additional, separate tools. Furthermore, the ampoule should be opened using as few components as possible. Furthermore, the monomer liquid should be available for preparing the bone cement paste with as little loss and as quickly as possible. The pumping of the monomer liquid into a bone cement powder for preparing the bone cement paste should be possible with as little effort as possible.

[0018] The device is intended to prepare the bone cement dough without mechanical mixing of the starting components. The device is intended to be capable of preparing the bone cement without an externally applied vacuum. The device is intended to be operable with as few steps as possible to minimize sources of error by the user. A further object of the invention is to provide a method with which bone cement can be prepared from two starting components, by means of which at least some of the objects already described are at least partially achieved. Preferred embodiments of the invention

[0019] A contribution to at least partially fulfilling at least one of the aforementioned objects is made by the features of the independent claims. The dependent claims provide preferred embodiments that contribute to at least partially fulfilling at least one of the objects.

[0020] A first embodiment of the invention comprises a device for providing a bone cement dough from two starting components, comprising a mixing unit comprising a hollow cylindrical cartridge with an interior space, wherein a discharge piston which is axially movable in the interior space is arranged in the interior space and divides the interior space into a proximal part of the interior space and a distal part of the interior space, wherein the proximal part and the distal part of the interior space are fluidly connected to one another via a conduit means, wherein a bone cement powder is stored as the first starting component in the proximal part of the interior space and wherein a delivery piston which is axially movable in the interior space is arranged in the distal part of the interior space, and a reservoir for a monomer liquid as the second starting component, which is or can be fluidly connected via an inlet channel to the distal part of the interior space for introducing the monomer liquid from the reservoir into the mixing unit, wherein the reservoir and the mixing unit are connected via an outlet channel,in particular an outlet channel which is disjoint to the inlet channel, are fluidly connected or connectable, via which a gas can be discharged from the interior into the reservoir, in particular in order to improve, in particular to facilitate and / or accelerate the introduction of the monomer liquid into the mixing unit.

[0021] In one embodiment of the device, the reservoir comprises a reservoir container in which at least one fluid-conducting closed ampoule with an ampoule body and an ampoule head is arranged and in which the monomer liquid is stored, and a cavity in the region of the ampoule head, wherein the cavity is fluid-conductingly connected to the inlet channel and comprises a connection to the ampoule, wherein the ampoule head is arranged at least in regions in the connection and the reservoir container comprises at least in sections a deformable region, so that tilting of the ampoule about a pivot point against the connection is possible.

[0022] In one embodiment of the device, the inlet channel has a smaller distance from the pivot point than the outlet channel.

[0023] In one embodiment of the device, the outlet channel opens into the interior space proximal to the inlet channel.

[0024] In one embodiment of the device, the inlet channel is designed as a funnel at an inlet channel end opposite the mixing unit.

[0025] In one embodiment of the device, the outlet channel has a minimum outlet channel diameter which corresponds to at least half the minimum inlet channel diameter of the inlet channel.

[0026] According to the invention, the inlet channel and the outlet channel are each formed at least in two parts, so that the mixing unit and the reservoir are fluidly connected to one another in a first channel position of the inlet channel and the outlet channel and are fluidly separated from one another in a second channel position of the inlet channel and the outlet channel.

[0027] According to the invention, the device has a closure element which closes or makes closable at least one part of the at least two-part inlet channel and the at least two-part outlet channel facing the mixing unit in a fluid-conducting manner.

[0028] According to the invention, in an alternative, the mixing unit and the reservoir are or can be connected to one another reversibly via a first positive connection, in particular in the region of the inlet channel and the outlet channel.

[0029] According to the invention, in an alternative, the closure element is a rotary valve through which the part of the two-part inlet channel and the two-part outlet channel facing the mixing unit extends and which, in a first rotary valve position, leaves the inlet channel and the outlet channel in the first channel position and, by rotating into a second rotary valve position, moves the inlet channel and the outlet channel into the second channel position.

[0030] According to the invention, in an alternative, the closure element can be brought into a closure position after separating the reservoir from the mixing unit by releasing the first positive connection in order to fluidly close the part of the two-part inlet channel and the two-part outlet channel facing the mixing unit.

[0031] In one embodiment of the device, the closure element is a screw.

[0032] In one embodiment of the device, the mixing unit and the reservoir are or can be reversibly connected to each other via a second form fit.

[0033] One embodiment of the invention is a method for providing a bone cement dough from two starting components by means of a device according to one of the preceding embodiments of the invention, comprising the steps: a. Flow of the monomer liquid from the reservoir through the inlet channel into the distal part of the interior space while simultaneously discharging a gas from the interior space through the outlet channel into the reservoir, b. Conveying the monomer liquid from the distal part of the interior space through the conduit means into the proximal part of the interior space by advancing the delivery piston toward the discharge piston.

[0034] In one embodiment of the method of the invention, before conveying the monomer liquid in step b., the part of the two-part inlet channel and the two-part outlet channel facing the mixing unit is fluidly closed by the closure element. General

[0035] In this description, range specifications also include the values ​​referred to as limits. A specification such as "in the range from X to Y" with respect to a quantity A therefore means that A can assume the values ​​X, Y, and values ​​between X and Y. Unilaterally limited ranges such as "up to Y" for a quantity A correspondingly mean the value Y and less than Y.

[0036] Some of the described features are linked to the term "essentially." The term "essentially" is to be understood in such a way that, under real-world conditions and manufacturing techniques, a mathematically precise interpretation of terms such as "superposition," "perpendicular," "diameter," or "parallelism" can never be exact, but only within certain manufacturing error tolerances. For example, "essentially perpendicular axes" enclose an angle of 85 degrees to 95 degrees to each other, and "essentially equal volumes" encompass a deviation of up to 5% by volume. A "device consisting essentially of plastic," for example, comprises a plastic content of ≥95 to ≤100% by weight. A "substantially complete filling of a volume B," for example, encompasses a filling of ≥95 to ≤100% by volume of the total volume of B.

[0037] The terms "proximal" and "distal" merely refer to the spatially opposite ends of the device or other structural units of the device and do not allow any conclusions to be drawn about the orientation relative to a human body, for example, a user of the device. Accordingly, "distal to..." and "proximal to..." or similar formulations merely express the spatial arrangement of two structural units of the device relative to each other. Detailed description

[0038] A first subject of the invention relates to a device for providing a bone cement dough from two starting components, comprising a mixing unit comprising a hollow cylindrical cartridge with an interior space, wherein a discharge piston is arranged in the interior space, which discharge piston is axially movable within the interior space and divides the interior space into a proximal part of the interior space and a distal part of the interior space, wherein the proximal part and the distal part of the interior space are fluidly connected to one another via a conduit, wherein a bone cement powder is stored in the proximal part of the interior space as the first starting component, and wherein a delivery piston is arranged in the distal part of the interior space and is axially movable within the interior space, and a reservoir for a monomer liquid as the second starting component, which reservoir is or can be connected via an inlet channel to the distal part of the interior space for introducing the monomer liquid from the reservoir into the mixing unit, wherein the reservoir and the mixing unit are or can be connected via an outlet channel,through which a gas can be discharged from the interior into the reservoir.

[0039] The device is used to mix a bone cement dough from a bone cement powder and a monomer liquid. Prior to mixing, the bone cement powder is stored in a mixing unit of the device, and the monomer liquid can be stored in a reservoir of the device. Preferably, at least one ampoule, preferably a glass ampoule, filled with the monomer liquid is stored in the reservoir. For example, one or two ampoule(s), preferably one or two glass ampoule(s), are stored in the reservoir.

[0040] The mixing unit serves to mix the bone cement dough from the bone cement powder and the monomer liquid after conveying the monomer liquid into the mixing unit, in particular after conveying the monomer liquid into an interior of the mixing unit.

[0041] The mixing unit has a hollow cylindrical cartridge. A hollow cylindrical cartridge is a tube-like container having an interior and a cartridge wall surrounding the interior. The cross-section of the cartridge can take on any shape. Due to the ease of manufacture and safer use of the device, the cross-section, and preferably also the cross-section of the interior, is circular. This allows for good handling for the user and, due to the absence of edges, reduces the risk of jamming of moving parts within the device. According to the invention, the cartridge can be made of a wide variety of materials or material combinations. For example, the device can be made of a polymer.Preferably, the polymer is a transparent polymer, as this allows the user to visually check the proper functioning of the device during use.

[0042] An axially movable discharge piston is arranged in the interior of the cartridge, dividing the interior into a proximal and a distal part. The bone cement powder is stored in the proximal part of the interior, i.e., proximal to the discharge piston. Preferably, the discharge piston is designed and interacts with the cartridge wall in such a way that the bone cement powder is essentially prevented from entering the distal part of the interior.

[0043] The discharge piston also serves to discharge the provided bone cement dough from the mixing unit. For this purpose, the discharge piston can be moved from its original position toward a discharge opening of the mixing unit. The discharge opening is preferably located on a side of the bone cement powder axially opposite the discharge piston and thus proximal to the discharge piston. In order to remove gas from the mixing unit, in particular the proximal part of the interior, in particular before the bone cement dough is formed, it is preferred that the discharge opening be designed to be gas-permeable. For example, the discharge opening can be closed with a gas-conducting closure, such as a plug, which can be removed to discharge the mixed bone cement dough from the discharge opening.

[0044] The mixing unit has a delivery piston that can move axially within the interior. The delivery piston is located in the distal part of the interior, i.e., distal to the discharge piston. The delivery piston closes the mixing unit at a distal end of the cartridge, preventing the monomer liquid conveyed from the reservoir into the distal part of the interior from flowing out of the cartridge. In an initial position of the device, the delivery piston is arranged in the interior such that, after the monomer liquid has been conveyed, it is stored between the discharge piston and the delivery piston in the distal part of the interior.

[0045] By advancing the delivery piston toward the discharge piston, i.e., advancing it in the proximal direction, the monomer fluid stored in the distal part of the interior space can be conveyed through a conduit into the proximal part of the interior space into the bone cement powder, which connects the proximal and distal parts of the interior space in a fluid-conducting manner. Fluid-conducting means that the distal and proximal parts of the interior space are connected in a way that is permeable to liquids, especially the monomer fluid, and to gases.To prevent bone cement powder from migrating from the proximal part into the distal part of the interior, the conduit is preferably equipped with a filter medium, in particular a porous disc, for example made of sintered polypropylene particles, sintered or compressed polyethylene fibers, cellulose felt, or cardboard, which makes the conduit impermeable to solids. In a variant of the device, at least one passage is provided in the discharge piston and / or between the discharge piston and the cartridge wall as a conduit, through which the distal part and the proximal part of the interior are fluidly connected to one another.In this case, a filter impermeable to the bone cement powder and permeable to the monomer liquid and gases, for example a porous disc made of sintered polypropylene particles, sintered or pressed polyethylene fibers, cellulose felt, or cardboard, can be arranged in or at one or both ends of the at least one passage. In a further variant of the device, the conduit means is one or more conduits arranged on the outside of the cartridge or in the cartridge wall and connecting the distal part and the proximal part of the interior. The discharge piston is bypassed in this variant.

[0046] A variant of the device is designed such that continued propulsion of the delivery piston toward the discharge piston, after the monomer liquid has been pumped from the distal part of the interior to the proximal part of the interior, causes the discharge piston to be propelled toward the discharge opening of the device. In this way, the bone cement paste prepared by mixing bone cement powder and monomer liquid can be discharged from the device through the discharge opening. This easily ensures that the bone cement paste can be expelled from the cartridge using the same drive mechanism used to pump the monomer liquid, namely the unidirectionally driven delivery piston.

[0047] In order to prevent the discharge piston from being accidentally propelled in the direction of the discharge opening, a locking means can be arranged on the discharge piston so that the discharge piston can lock with the cartridge, in particular with the cartridge wall, wherein this locking cannot be released by the pressure to be applied when conveying the monomer liquid into the proximal part of the interior, but can be released by a direct pressure of the delivery piston acting on the discharge piston.

[0048] The locking mechanism ensures that the monomer liquid can initially be pressed into the bone cement powder, with the dispensing piston maintaining its original position relative to the cartridge and the interior. Only after the monomer liquid has been largely pressed into the bone cement powder, and the bone cement paste is thus present in the proximal part of the cartridge's interior, can the bone cement paste be subsequently pressed out of the proximal part of the cartridge using the dispensing piston. The force required to release the locking mechanism is therefore greater than the force required to convey the monomer liquid via the conduit into the proximal part of the interior.

[0049] The reservoir serves to hold the monomer liquid before it is mixed with the bone cement powder in the mixing unit to form the bone cement paste. Preferably, the monomer liquid is stored in the reservoir until a user of the device wishes to prepare the bone cement.

[0050] To convey the monomer liquid from the reservoir into the distal part of the interior of the mixing unit, the reservoir and the distal part of the interior of the mixing unit are fluidly connected or connectable via an inlet channel. For this purpose, the inlet channel has an inlet channel diameter that allows the monomer liquid to be conveyed from the reservoir into the mixing unit as quickly as possible. For example, the inlet channel diameter, in particular a minimum inlet channel diameter, is in a range from 1 mm to 4 mm.

[0051] In order to improve, and in particular to accelerate, the conveying of the monomer liquid from the reservoir into the distal part of the interior space, the reservoir and the distal part of the interior space are, in addition to the inlet channel, fluidically connected or connectable to one another via an outlet channel, in particular disjointed from the inlet channel. If the reservoir and the distal part of the interior space are fluidically connected to one another via the inlet channel and the outlet channel, this allows for improved, in particular accelerated, conveying of the monomer liquid from the reservoir via the inlet channel into the distal part of the interior space of the mixing unit, while at the same time, a gas from the distal part of the interior space, which is displaced from the distal part of the interior space by the monomer liquid entering the distal part of the interior space, can be discharged into the reservoir via the outlet channel.The inlet channel and the outlet channel thus synergistically ensure improved mass transfer between the reservoir and the mixing unit.

[0052] The monomer liquid can be pumped from the reservoir via the inlet channel into the mixing unit, for example, by gravity, by a negative pressure in the mixing unit, in particular in the interior of the cartridge, or a combination thereof, with pumping by gravity being preferred. In particular when pumping by gravity, the outlet channel improves the introduction of the monomer liquid into the mixing unit, since the gas displaced from the interior can be discharged into the reservoir. The reservoir can be made of a wide variety of materials or material combinations. For example, the reservoir can be made of a polymer. The polymer is preferably a transparent polymer, since this allows the user to visually check that the reservoir is functioning properly, in particular that the monomer liquid is not flowing out of the reservoir, during use.

[0053] The reservoir can be designed in different ways to provide the monomer liquid. For example, the monomer liquid can have a reservoir interior in which the monomer liquid flows freely.

[0054] Preferably, the monomer liquid is stored within the reservoir in one or more separate containers, which facilitates handling and filling of the device, in particular the reservoir, and the sterile provision of the monomer liquid. For example, the monomer liquid is provided in the reservoir in a container in the form of a bag. A bag is understood to be a non-rigid, largely flexible storage option that can store the monomer liquid hermetically and sterilely and can be opened by means of an opening means, for example by piercing, cutting, or tearing. The bags can, for example, be made of a multilayer composite film, preferably having an EVOH barrier layer. Optionally, the bags can have a metal coating, in particular an aluminum coating.

[0055] Preferably, at least one ampoule containing the monomer liquid, preferably a glass ampoule, is stored in the reservoir. For example, two ampoules containing the monomer liquid, preferably glass ampoules, are stored in the reservoir. Ampoules, especially glass ampoules, are preferred due to their good sterilizability and easy and reliable opening by manual force.

[0056] An embodiment of the device is characterized in that the reservoir has a reservoir container in which at least one fluid-conducting closed ampoule with an ampoule body and an ampoule head is arranged and in which the monomer liquid is stored, and a cavity in the region of the ampoule head, wherein the cavity is fluid-conductingly connected to the inlet channel and comprises a connection to the ampoule, wherein the ampoule head is arranged at least in regions in the connection and the reservoir container comprises at least in sections a deformable region, so that tilting of the ampoule about a pivot point against the connection is possible.

[0057] In this embodiment, the reservoir comprises a reservoir container for accommodating one or more, preferably two, fluid-conducting, closed ampoule(s), in particular a glass ampoule(s), filled with the monomer liquid, having an ampoule head and an ampoule body. The reservoir container encloses the at least one ampoule, in particular at least the ampoule body, so that the ampoule can be safely stored in the reservoir until use. The reservoir container can, for example, be in the form of a hollow cylinder into which the at least one ampoule is inserted. To improve the transportability of the device, the reservoir container is shaped in such a way, for example by having a lid, that the ampoule cannot inadvertently escape from the device, in particular the reservoir.Preferably, the reservoir container is shaped such that two ampoules, in particular two ampoules next to each other, preferably with substantially parallel longitudinal axes, can be stored in the reservoir.

[0058] Furthermore, the reservoir serves to open the at least one ampoule in a fluid-conducting manner. For this purpose, the reservoir has a hollow space which is connected via a connection to the ampoule arranged in the reservoir container. The ampoule is mounted in the reservoir in such a way that the ampoule head points in the direction of the hollow space, while the ampoule body is at least partially, preferably completely, arranged in the reservoir container. The connection extends between the hollow space and the reservoir container in such a way that the ampoule head is at least partially arranged in the connection. For this purpose, the connection has a connection diameter which allows the ampoule head to be inserted at least partially into the connection. In one embodiment, the connection has a connection diameter which allows the ampoule head to be inserted completely into the connection.Preferably, the connection diameter is smaller than the diameter of the ampoule body so that the latter cannot be inserted into the connection. For example, the connection is designed as a ring or hollow cylinder and the ampoule head is at least partially surrounded by this ring or hollow cylinder. The connection has a structural integrity which exceeds the structural integrity of the ampoule so that the ampoule can break if the ampoule is pressed against the connection. In order to open the ampoule, or in the case of two or more ampoules, all ampoules, the reservoir container has a deformable region at least in sections, in particular adjacent to a transition from the ampoule head to the ampoule body of the ampoule. In one embodiment, the reservoir container is fully deformable. The deformable region allows the ampoule to be tilted about a pivot point against the connection.The connection diameter is adapted to the ampoule head in such a way that, upon tilting, at least the end of the ampoule body facing away from the ampoule head is tilted about the pivot point, while at least the end of the ampoule head facing away from the ampoule body remains within the connection, so that the ampoule is opened in a fluid-conducting manner by an at least partial bursting of the ampoule, particularly in the area of ​​an ampoule neck between the ampoule head and ampoule body. The connection primarily serves to fix the ampoule head against a tilting movement of the ampoule about the pivot point. For example, the connection diameter is no more than 10% larger than the diameter of the ampoule head, so that even a relatively slight tilt of the ampoule leads to its fluid-conducting opening.

[0059] After a fluid-conducting opening of at least one ampoule, the monomer liquid can flow from the ampoule into the cavity. The cavity is fluidly connected to the mixing unit, in particular to the distal part of the interior of the mixing unit, via the inlet channel. Conveying of the monomer liquid from the cavity via the inlet channel into the mixing unit can be triggered, for example, by gravity, by a negative pressure in the mixing unit, in particular in the interior of the cartridge, or a combination thereof, with conveying by gravity being preferred. Particularly when conveying by gravity, the outlet channel improves the introduction of the monomer liquid into the mixing unit.

[0060] One embodiment of the device is characterized in that the inlet channel is at a shorter distance from the pivot point than the outlet channel. In particular, an inlet channel end opposite the mixing unit and facing the reservoir is at a shorter distance, in particular a shorter spatial distance, from the pivot point than an outlet channel end opposite the mixing unit and facing the reservoir.

[0061] When tilted about the pivot point, the at least one ampoule is opened in a fluid-conducting manner against the connection in the vicinity of the pivot point, in particular in the region of the ampoule neck, so that the monomer liquid can flow from the at least one ampoule into the cavity. If the inlet channel, in particular the inlet channel end opposite the mixing unit, is arranged closer to the pivot point than the outlet channel, in particular the outlet channel end opposite the mixing unit, then the monomer liquid will flow essentially completely through the inlet channel into the mixing unit, in particular the distal part of the interior of the mixing unit, with a substantially vertical spatial orientation of the device and without further action by a user of the device, while at the same time the outlet channel remains essentially free of the mixing unit and thus allows improved discharge of the gas displaced from the interior.This arrangement of the inlet channel and outlet channel to each other thus improves the mass transfer between the mixing unit and the reservoir.

[0062] The inlet channel and the outlet channel can open into the interior, in particular the distal part of the interior, at the same spatial height along a longitudinal axis of the device, in particular the mixing unit. In this embodiment, the inlet channel and the outlet channel open into the distal part of the interior of the mixing unit "side by side" in the broadest sense.

[0063] One embodiment of the device is characterized in that the outlet channel opens into the interior space, in particular into the distal part of the interior space, proximal to the inlet channel. The outlet channel, in particular an outlet channel end facing the mixing unit, is thus closer to the discharge piston than the inlet channel, in particular an inlet channel end facing the mixing unit. Thus, the inlet channel, in particular the inlet channel end facing the mixing unit, opens closer to the delivery piston than the outlet channel, in particular the outlet channel end facing the mixing unit. This reduces the risk of the monomer liquid flowing out of the interior space through the outlet channel directly after flowing into the interior space through the inlet channel, in particular if, as is preferred due to the most compact design of the device possible, the inlet channel and the outlet channel open close to one another into the distal part of the interior space.Preferably, the outlet duct and the inlet duct open into the interior no more than 1 cm apart from each other.

[0064] In order to ensure that the monomer liquid from the reservoir, preferably from the at least one fluid-conducting ampoule stored in the reservoir, is conveyed essentially completely via the inlet channel and not via the outlet channel into the distal part of the interior, one embodiment of the device is characterized in that the inlet channel is designed as a funnel at the inlet channel end opposite the mixing unit and facing the reservoir. The funnel design facilitates the flow of the monomer liquid into the inlet channel. In particular when storing the monomer liquid in an ampoule, in particular a glass ampoule, the funnel design can be advantageous because the monomer liquid may flow out of the at least one fluid-conducting ampoule irregularly, for example in bursts.The funnel shape improves the absorption of the monomer liquid into the inlet channel, especially when the flow is irregular. The funnel can, for example, have a diameter ranging from 1 cm to 4 cm. The cross-sectional area of ​​the funnel can be round, square, or elliptical.

[0065] The funnel shape can cover different portions of the total length of the inlet channel. For example, the inlet channel can be designed as a funnel over 10% to 95%, preferably over 30% to 90%, more preferably over 50% to 90% of the total length of the inlet channel.

[0066] The exhaust port and the inlet port can have different diameters.

[0067] One embodiment of the device is characterized in that the outlet channel has a minimum outlet channel diameter that corresponds to at least half the minimum inlet channel diameter of the inlet channel. The minimum inlet channel diameter is thus preferably a maximum of twice the minimum outlet channel diameter.

[0068] This ensures that the gas from the interior can be discharged into the reservoir via the outlet channel quickly enough so as not to slow down the flow of the monomer liquid from the reservoir into the interior.

[0069] In a preferred embodiment, the minimum outlet channel diameter and the minimum inlet channel diameter are substantially equal.

[0070] The inlet channel and the outlet channel are formed at least in two parts, preferably in two or three parts, more preferably in two parts, so that the mixing unit, in particular the distal part of the interior of the mixing unit, and the reservoir, preferably the cavity of the reservoir, are fluidly connected to one another in a first channel position of the inlet channel and the outlet channel and are fluidly separated from one another in a second channel position of the inlet channel and the outlet channel. The inlet channel and the outlet channel can preferably be reversibly moved into the first channel position and the second channel position. A one-piece channel cannot reversibly assume two channel positions.

[0071] At least two components, preferably two or three components, more preferably two components, are involved in the formation of the inlet channel and the outlet channel, and the inlet channel and the outlet channel extend through these components. For example, the inlet channel is formed by a fluid-conducting connection of two disjoint hoses.

[0072] Preferably, the part of the channels facing the mixing unit runs in one of the components and the part of the channels facing the reservoir runs in another component.

[0073] Preferably, the inlet channel and the outlet channel are formed by the same components.

[0074] Due to the at least two-part design of the inlet channel and outlet channel, both channels can establish a fluid-conducting connection between the reservoir and the mixing unit, preferably reversibly, in a first channel position and separate the reservoir and the mixing unit in a fluid-conducting manner in a second channel position. For example, the inlet channel is formed by a fluid-conducting connection of two previously disjointed hoses, with the fluid-conductingly connected hoses representing the first channel position and the two separate hoses representing the second channel position.

[0075] Due to the at least two-part design of the inlet channel and the outlet channel, a user of the device can thus control the mass transfer between the mixing unit and the reservoir.

[0076] Preferably, the inlet channel and the outlet channel can be moved to the first or second channel position simultaneously.

[0077] The device comprises a closure element that fluidically closes or renders closable at least one part of the at least two-part inlet channel facing the mixing unit, i.e., adjacent to the mixing unit, and at least one part of the at least two-part outlet channel facing the mixing unit, i.e., adjacent to the mixing unit. Preferably, the device fluidically closes or renders closable at least one part of the at least two-part outlet channel facing the mixing unit, i.e., adjacent to the mixing unit. For example, the device comprises a plug that can be reversibly inserted into the inlet channel end and the outlet channel end facing the mixing unit in order to fluidically separate the mixing unit and the reservoir.

[0078] The closure element facilitates a substantially complete conveyance of the monomer liquid from the distal part of the interior through the conduit into the proximal part of the interior. Without the closure element, the monomer liquid, or portions thereof, could be discharged from the mixing unit again through the inlet channel and / or the outlet channel during conveyance into the proximal part of the interior.

[0079] One embodiment of the device is characterized in that the mixing unit and the reservoir are reversibly connected or connectable to one another via a first positive connection. Thus, the mixing unit and the reservoir are designed to be reversibly separable from one another, which simplifies use of the device for a user. This allows for easy separation of the reservoir, which is no longer required after the monomer liquid has been conveyed into the mixing unit, in particular into the distal part of the interior of the mixing unit. This simplifies the provision, and preferably the discharge, of the bone cement dough by means of the mixing unit, in particular by improving handling.

[0080] Preferably, the same components which form the at least two-part inlet channel and the at least two-part outlet channel are involved in the formation of the first form fit.

[0081] In one embodiment, the inlet channel and the outlet channel are in the first channel position when the first positive locking is formed and in the second channel position when the first positive locking is released.

[0082] The closure element can be shaped differently to separate the mixing unit and the reservoir in a fluid-conducting manner.

[0083] One embodiment of the device is characterized in that the closure element is a rotary valve through which the part of the two-part inlet channel and the two-part outlet channel facing the mixing unit extends, i.e. the part of the two-part inlet channel and the two-part outlet channel adjacent to the mixing unit, and which, in a first rotary valve position, leaves the inlet channel and the outlet channel in the first channel position and, by rotating it into a second rotary valve position, moves the inlet channel and the outlet channel into the second channel position. The part of the at least two-part inlet channel and the two-part outlet channel facing away from the mixing unit and facing the reservoir does not extend through the rotary valve. The rotary valve thus forms the component of the at least two-part inlet channel and outlet channel that forms the parts of the two channels facing the mixing unit.If the rotary valve is in the first rotary valve position, the inlet channel and the outlet channel are in the first channel position, whereby the mixing unit, in particular the distal part of the interior of the mixing unit, and the reservoir are fluidically connected to one another. If the rotary valve is in the second rotary valve position, the inlet channel and the outlet channel are in the second channel position, whereby the mixing unit, in particular the distal part of the interior of the mixing unit, and the reservoir are fluidically separated from one another. By turning the rotary valve to the second rotary valve position, and thus moving the inlet channel and the outlet channel into the second channel position, the two parts of the inlet channel and the two parts of the outlet channel are spatially shifted relative to one another in such a way that the exchange of substances between the respective parts of the inlet channel and the outlet channel is prevented.By rotating the rotary valve into the first rotary valve position, and thus bringing the inlet channel and the outlet channel into the first channel position, the two parts of the inlet channel and the two parts of the outlet channel are arranged relative to one another in such a way that a mass exchange between the corresponding parts of the inlet channel and the outlet channel is possible.

[0084] One embodiment of the device is characterized in that, after separating the reservoir from the mixing unit by releasing the first positive locking, the closure element can be moved into a closed position in order to fluidly close the part of the two-part inlet channel and the two-part outlet channel facing the mixing unit. In this embodiment, by releasing the first positive locking, the parts of the at least two-part inlet channel and the two-part outlet channel are fluidly separated, wherein preferably the part of the inlet channel and the outlet channel facing the reservoir, i.e. adjacent to the reservoir, is removed from the mixing unit together with the reservoir by releasing the first positive locking, and the parts of the inlet channel and the outlet channel adjacent to the mixing unit remain on the mixing unit, for example as feedthroughs in the cartridge wall in the region of the distal part of the interior.In this embodiment, by releasing the first positive locking, the inlet channel and the outlet channel are moved from the first channel position to the second channel position. The closure element serves to close the remaining parts of the inlet channel and the outlet channel on the mixing unit, preferably from outside the mixing unit, after the reservoir has been removed. For this purpose, the closure element is moved into the closed position. For example, the closure element is a plug, which can be moved into the closed position by being inserted into the remaining part of the inlet channel and the outlet channel on the mixing unit, preferably from outside the mixing unit.

[0085] One embodiment of the device is characterized in that the closure element is a screw. The screw preferably has an external thread that interacts with an internal thread, preferably located outside the mixing unit, such that, after releasing the first positive connection and removing the part of the inlet channel and the outlet channel facing the reservoir, screwing the screw in toward the cartridge wall causes a fluid-conducting closure of the part of the inlet channel and the outlet channel remaining on the mixing unit, preferably by means of a screw syringe.

[0086] Preferably, the screw has wings to facilitate screwing the device into the locking position for a user.

[0087] The first form fit may represent the only mechanical connection between the mixing unit and the reservoir.

[0088] An embodiment of the device is characterized in that the mixing unit and the reservoir are reversibly connected or connectable to each other via a second positive connection, in addition to the first positive connection.

[0089] In this embodiment, the mixing unit and the reservoir are connected to each other via two positive locks.

[0090] When opening at least one ampoule by tilting it around the pivot point against the connection, a sufficiently high force must be exerted on the ampoule to overcome its structural integrity. This force increases further when using more than one ampoule, preferably two ampoule, if these are to be opened simultaneously by tilting it around the pivot point against the connection, as is preferred. This force acts on the contact points between the reservoir and the mixing unit.If the reservoir and the mixing unit were connected only via the first positive connection, the force for opening the at least one ampoule would act entirely on this first positive connection, so that, since the components that form the at least two-part inlet channel and the at least two-part outlet channel are preferably involved in the first positive connection, the inlet channel and / or the outlet channel could bend or even tear off. This would impede or even prevent a substantially complete conveyance of the monomer liquid from the reservoir into the mixing unit, in particular the distal part of the interior.

[0091] The second positive connection between the connecting element and the mixing unit ensures that the force required to open the at least one ampoule is distributed between the two positive connections, so that the risk of damage to the device due to tilting when opening the at least one ampoule is reduced.

[0092] Due to the two positive locking devices, the reservoir is connected to the mixing unit in such a stable manner that the at least one ampoule can be opened by tilting it around the pivot point against the connection without damaging the device and without requiring additional aids in addition to the device for opening the at least one ampoule.

[0093] The second form fit between the mixing unit and the reservoir can be realized in different ways.

[0094] In one embodiment of the device, the second positive connection is formed by a clasp. The clasp is preferably formed from two clasp notches on a reservoir outer surface, such as an outer surface of the reservoir container, the cavity, or the connection, as well as two clasp protrusions on a mixing element outer surface, preferably a cartridge outer surface. The two clasp protrusions can be reversibly inserted into the two clasp notches to form the second positive connection. This allows for a second positive connection that can be quickly and easily created and released, is stable, and allows for secure opening of the at least one ampoule by tilting it around the pivot point.

[0095] The pivot point as well as the first form closure and the second form closure can be arranged spatially in different ways relative to each other.

[0096] One embodiment of the device is characterized in that the pivot point, the first positive connection and the second positive connection form the corners of a triangle in a side view, in particular a side view of the device. In this embodiment, the pivot point and the two positive connections lie in a common plane, but are not arranged on a straight line running in this plane. Preferably, the longitudinal axis of the cartridge lies within this plane or runs at least parallel to this plane. The arrangement in the form of a triangle improves the distribution of the force required for the fluid-conducting opening of the at least one ampoule, in particular when the ampoule is tilted about the pivot point within or parallel to the plane of the triangle.Furthermore, such an arrangement ensures that the pivot point is fixed in this plane and does not shift, which facilitates a reproducible opening of at least one ampoule.

[0097] The pivot point as well as the first form fit and the second form fit can have different distances from each other.

[0098] One embodiment of the device is characterized in that the second positive locking element is located at a shorter distance from the first positive locking element than the pivot point. In this embodiment, the distance between the pivot point and the first positive locking element is thus greater than the distance between the second positive locking element and the first positive locking element. Particularly when the pivot point and the two positive locking elements are arranged in a triangle, this allows both an improved distribution of the force required to open the ampoule when tilting between the two positive locking elements and, at the same time, a space-saving design of the device. This makes handling of the device particularly easy for the user.

[0099] Preferably, the pivot point and the two positive locking elements form the vertices of a triangle in a side view, with the pivot point and the second positive locking element having the smallest distance between the three possible points. This further improves the force distribution between the two positive locking elements and allows for a more space-saving design of the device.

[0100] One embodiment of the device is characterized in that the first positive locking mechanism, the second positive locking mechanism, and the pivot point each lie on a straight line running parallel to a longitudinal axis of the cartridge, with the straight lines having different spacings from the longitudinal axis of the cartridge. This arrangement improves the distribution of the force required to open the ampoule when tilting between the two positive locking mechanisms and simultaneously allows for the most space-saving design possible for the device. This arrangement particularly facilitates handling of the device by the user.

[0101] Preferably, the pivot point and the two positive locking elements form the corner points of a triangle, wherein the triangle lies in a plane in which the longitudinal axis of the cartridge also lies or to which the longitudinal axis of the cartridge runs at least parallel.

[0102] A further subject of the invention relates to a method for providing a bone cement dough from two starting components by means of a device according to the invention comprising the following steps: a. Flow of the monomer liquid from the reservoir through the inlet channel into the distal part of the interior space while simultaneously discharging a gas from the interior space through the outlet channel into the reservoir, b. Conveying the monomer liquid from the distal part of the interior space through the conduit means into the proximal part of the interior space by advancing the delivery piston toward the discharge piston.

[0103] Preferably, the flow of the monomer liquid in step a. occurs according to gravity. For this purpose, the device is held by a user such that the discharge piston is positioned spatially above the delivery piston, preferably vertically above the delivery piston. As the monomer liquid flows through the inlet channel into the distal part of the interior space, a temporary monomer liquid level can form within the inlet channel, which results from an inlet volume of the monomer liquid into the inlet channel and an outlet volume of the monomer liquid from the inlet channel into the distal part of the interior space.Due to the aforementioned embodiments of the device, the monomer liquid level is preferably always formed distal to the outlet channel end of the outlet channel facing the reservoir, so that, when the device is aligned vertically with the proximal cartridge end upwards, essentially no monomer liquid enters the outlet channel on the reservoir side.

[0104] By driving the delivery piston towards the discharge piston in step b, the spatial distance between the two pistons is reduced, so that, depending on the volume of the monomer liquid present in the distal part of the interior space, from a certain spatial proximity, the monomer liquid is conveyed from the distal part of the interior space through the conduit into the proximal part of the interior space.

[0105] When the monomer liquid begins to be pumped into the proximal part of the interior, there is contact between the monomer liquid and the bone cement powder stored in the proximal part of the interior, which is accompanied by the formation of the bone cement dough.

[0106] An embodiment of the method is characterized in that, before conveying the monomer liquid in step b, the part of the two-part inlet channel and the two-part outlet channel facing the mixing unit is fluidly closed by the closure element.

[0107] This facilitates a substantially complete conveyance of the monomer liquid from the distal part of the interior through the conduit into the proximal part of the interior, without significant portions of the monomer liquid being discharged from the mixing unit by the propulsion of the delivery piston from the distal part of the interior through the inlet channel and / or the outlet channel. Furthermore, a user does not have to spatially align the device in such a way that this discharge essentially does not occur.

[0108] The delivery piston can be advanced toward the discharge piston in various ways. For example, a user of the device can advance the delivery piston manually, in particular by applying force to a rod or axle. In another embodiment, the cartridge and the delivery piston together form a thread, via which the delivery piston can be screwed into the cartridge toward the discharge piston. Preferably, the cartridge has an internal thread and the delivery piston an external thread, which interact in a positive and / or non-positive manner to enable the delivery piston to advance.

[0109] In a further embodiment of the method, the delivery piston is driven forward using a mechanical aid.

[0110] One embodiment of the method is characterized in that, to drive the delivery piston, the device is inserted into a dispensing device, in particular a dispensing gun for bone cement pastes. Dispensing guns for bone cement pastes are known to those skilled in the art.

[0111] The formation of the bone cement dough from the two starting components begins with the conveyance of the monomer liquid from the rear part to the front part of the interior. This preferably occurs with the two starting components mixed as evenly as possible in order to obtain a bone cement dough that is as homogeneous as possible. The two starting components can be mixed in different ways. In one embodiment of the method, the mixing takes place with the active participation of the user of the device, for example, by shaking the device or by activating a mixing element in the front part of the interior, in particular a stirrer.

[0112] One embodiment of the method is characterized in that the monomer liquid is distributed throughout the bone cement powder with the aid of a hydrophilic additive. One advantage is that this takes place without the active participation of the device user, thus avoiding potential user errors during mixing. One potential error is that the user does not mix across the entire length of the front part of the interior, resulting in parts of the bone cement powder not being wetted with monomer liquid. Another advantage is that the device can be designed more simply and with fewer moving parts, which reduces both the risk of malfunctions and the device's manufacturing costs.

[0113] The device is characterized in that it provides a bone cement dough made up of two starting components. A bone cement dough is understood to be a substance that is suitable in the field of medical technology for creating a stable connection between artificial joints, such as hip and knee joints, and bone material. Upon hardening, a bone cement dough becomes a bone cement. These bone cements are preferably polymethyl methacrylate bone cements (PMMA bone cements). PMMA bone cements have long been used in medical applications and date back to the work of Sir Charnley (cf. Charnley, J. Anchorage of the femoral head prosthesis of the shaft of the femur. J. Bone Joint Surg. 1960; 42, 28-30.). PMMA bone cements can be produced from a bone cement powder as the first starting component and a monomer liquid as the second starting component.With a suitable composition, the two starting components can be stored separately. When the two starting components are brought into contact, swelling of the polymer components of the bone cement powder creates a plastically deformable bone cement paste. This initiates radical polymerization of the monomer. As the monomer polymerization progresses, the viscosity of the bone cement paste increases until it completely hardens.

[0114] A bone cement powder is understood to be a powder comprising at least one particulate polymethyl methacrylate and / or a particulate polymethyl methacrylate copolymer. Examples of copolymers are styrene and / or methyl acrylate. In one embodiment, the bone cement powder can additionally comprise a hydrophilic additive that supports the distribution of the monomer liquid within the bone cement powder. In another embodiment, the bone cement powder can additionally comprise an initiator that initiates the polymerization. In another embodiment, the bone cement powder can additionally comprise an X-ray opaque. In yet another embodiment, the bone cement powder can additionally comprise pharmaceutically active substances, such as antibiotics.

[0115] The bone cement powder preferably comprises, as a hydrophilic additive, at least one particulate polymethyl methacrylate and / or a particulate polymethyl methacrylate copolymer, an initiator, and a radiopaque, or consists of these components. Further preferably, the bone cement powder comprises, or consists of, at least one particulate polymethyl methacrylate and / or a particulate polymethyl methacrylate copolymer, an initiator, a radiopaque, and a hydrophilic additive. Most preferably, the bone cement powder comprises, or consists of, at least one particulate polymethyl methacrylate and / or a particulate polymethyl methacrylate copolymer, an initiator, a radiopaque, a hydrophilic additive, and an antibiotic.

[0116] According to the invention, the particle size of the particulate polymethyl methacrylate and / or the particulate polymethyl methacrylate copolymer of the bone cement powder of the sieve fraction can correspond to less than 150 µm, preferably less than 100 µm.

[0117] According to the invention, the hydrophilic additive can be particulate and / or fibrous. In a further embodiment, the hydrophilic additive can be sparingly soluble, preferably insoluble, in methyl methacrylate. In a further embodiment, the hydrophilic additive can have an absorption capacity of at least 0.6 g of methyl methacrylate per gram of hydrophilic additive. In a further embodiment, the hydrophilic additive can comprise a chemical substance with at least one OH group. It can preferably be provided that the hydrophilic additive has covalently bonded OH groups on its surface. Examples of such preferred hydrophilic additives can be additives selected from the group comprising cellulose, oxycellulose, starch, titanium dioxide, and silicon dioxide, with pyrogenic silicon dioxide being particularly preferred.In one embodiment, the particle size of the hydrophilic additive of the sieve fraction can be less than 100 µm, preferably less than 50 µm, and most preferably less than 10 µm. The hydrophilic additive can be present in an amount of 0.1 to 2.5 wt.% based on the total weight of the bone cement powder.

[0118] According to the invention, the initiator may contain dibenzoyl peroxide or consist of dibenzoyl peroxide.

[0119] According to the invention, a radiopaque agent is understood to mean a substance that allows the bone cement to be made visible on X-ray images. Examples of radiopaque agents can include barium sulfate, zirconium dioxide, and calcium carbonate. According to the invention, the pharmaceutically active substance can comprise one or more antibiotics and, optionally, added cofactors for the one or more antibiotics. Preferably, the pharmaceutically active substance consists of one or more antibiotics and, optionally, added cofactors for the one or more antibiotics. Examples of antibiotics include gentamicin, clindamycin, and vancomycin. According to the invention, the monomer liquid can comprise the monomer methyl methacrylate or consist of methyl methacrylate.In one embodiment, the monomer liquid comprises, in addition to the monomer, an activator dissolved therein, such as N,N-dimethyl-p-toluidine, or consists of methyl methacrylate and N,N-dimethyl-p-toluidine. Figures

[0120] The invention is further illustrated below by means of exemplary figures. The invention is not limited to the figures.

[0121] It shows Fig. 1 shows a schematic longitudinal section of an exemplary device for providing a bone cement dough comprising a mixing unit and a reservoir with an ampoule filled with a monomer liquid, Fig. 2 shows the device from Figures 1 , wherein a first form fit, a second form fit and a pivot point are indicated, Fig. 3 a perspective side view of the mixing unit of the device from the Figures 1 and 2 , Fig. 4the device from the Figures 1 to 3when the ampoule is opened in a fluid-conducting manner and the monomer liquid is conveyed into the mixing unit, Fig. 5, the device from the Figures 1 to 4 , wherein the reservoir is separated from the mixing unit, Fig. 6 the device from the Figures 1 to 5 with a fluid-conducting closed closure element in the form of a screw, Fig. 7 the device from the Figures 1 to 6 when conveying the monomer liquid into the bone cement powder, Fig. 8 the device from the Figures 1 to 7 with prepared bone cement dough, Fig. 9 the device from the Figures 1 to 8 when dispensing the bone cement dough, Fig. 10 a schematic longitudinal section of another exemplary device for providing a bone cement dough comprising a mixing unit and a reservoir with an ampoule filled with a monomer liquid, Fig. 11 the device from Figure 10when the ampoule is opened in a fluid-conducting manner and the monomer liquid is conveyed into the mixing unit, Fig. 12 the device from the Figures 10 and 11 with a fluid-conducting closed closure element in the form of a rotary valve, and Fig. 13 a flow diagram of a method for providing a bone cement dough. Description of the characters

[0122] Figure 1 shows a schematic longitudinal section of an exemplary embodiment of a device 100 for preparing a bone cement dough from two starting components in an initial state. The device 100 comprises a mixing unit 200 and a reservoir 300, which are reversibly separably connected to one another via a first form fit and a second form fit (cf. Figures 2 and 3 ).

[0123] The mixing unit 200 has a tubular structure and comprises a hollow cylindrical cartridge 210 with an interior 215, which is divided into a proximal part 216 and a distal part 217 of the interior 215 by a discharge piston 220 that is reversibly axially displaceable within the interior 215. A bone cement powder 500 as a first starting component of the bone cement dough is stored in the proximal part 216 of the interior 215, and an ampoule 330 containing a monomer liquid 510 as a second starting component of the bone cement dough is stored in the reservoir 300. The bone cement powder 500 contains particulate polymethyl methacrylate as its main component and a hydrophilic additive with which the monomer liquid 510 can be distributed in the bone cement powder 500 without the need for a mixing device.

[0124] The discharge piston 220 is designed to be impermeable to solids, so that no bone cement powder 500 can pass from the proximal part 216 into the distal part 216 of the interior space 215. The discharge piston 220 has a conduit 230 (marked merely as an example) in the form of several passages, through which a fluid-conducting connection is formed between the proximal part 216 and the distal part 217 of the interior space 215. The conduit 230 is sealed by a filter medium 235 in the form of a porous disc, impermeable to solids or bone cement paste, wherein the porous disc allows the monomer liquid 510 to be conveyed smoothly from the distal part 217 into the proximal part 216 of the interior space 215. In the illustrated embodiment of the device 100, the filter means 235 is arranged on the proximal end of the conduit means 230 facing the proximal part 216 of the interior space 215.In further embodiments not shown, the filter means 235 is arranged on the distal end of the conduit means 230 facing the distal part 217 of the interior space 215 or at both ends of the conduit means 230. An advantage of a filter means 235 arranged as shown is that the bone cement paste forming in the proximal part 216 of the interior space 215 cannot clog the conduit means 230.

[0125] Distal to the discharge piston 220, within the distal part 217 of the interior space 215, is a delivery piston 240 that is axially movable within the interior space 215. The delivery piston 240 fluidically closes off a distal cartridge end 212 of the cartridge 210. The mixing unit 200 further has a discharge opening 250 at a proximal cartridge end 211 opposite the distal cartridge end 212, which delimits the region of the proximal part 216 of the interior space 215 of the cartridge 210 facing away from the discharge piston 220. In the initial state of the device 100, the discharge opening 250 is closed by a closure cap 260 with a plug 265, so that no bone cement powder 500 can escape from the cartridge 210.The plug 265 is designed to be gas-permeable in order to be able to transfer a gas 530, which is present in the interior space 215, through the bone cement powder 500 and out of the device 100 before the formation of the bone cement dough begins.

[0126] The reservoir 300 has a tubular reservoir container 310 in which two ampoules 330, in particular two glass ampoules, are stored next to one another (only one of the ampoules 330 is visible in the view shown). The ampoules 330 each have an ampoule body 331, an ampoule head 332 facing the mixing unit 200, and an ampoule neck 333 located between the ampoule body 331 and the ampoule head 332, which acts as a predetermined breaking point for the ampoules 330. The monomer liquid 510 is stored in the ampoules 330. The ampoule head 332 of the ampoules 330 is arranged in sections in a connection 350, which connects a cavity 340 of the reservoir 300 to the ampoules 330. The connection 350 has a connection diameter 355 which is approximately 5% larger than a diameter of the ampoule heads 332, so that the connection 350 fixes the ampoule heads 332 against tilting within the plane of the drawing.In order to enable tilting of the ampoules 330, in particular the ampoule heads 332, against the connection 350, wherein in the embodiment shown tilting in the plane of the drawing is possible, the reservoir container 310 has a deformable region 320 in the region of a transition from the connection 350 to the ampoule body 331.

[0127] A filter element 345 is arranged within the cavity 340 in the reservoir 300, so that fragments of the ampoules 330 cannot enter the mixing unit 200 via the cavity 340 after the ampoules have been opened in a fluid-conducting manner, but are retained on the filter element 345.

[0128] The reservoir 300, in particular the cavity 340, is fluidically connected to the mixing unit 200, in particular to the distal part 217 of the interior space 215, via an inlet channel 400 and an outlet channel 410. In the view shown, the inlet channel 400 and the outlet channel 410 are in a first channel position, so that the reservoir 300 and the mixing unit 200 are fluidically connected to one another via the two channels 400, 410. The inlet channel 400 serves to introduce the monomer liquid 510 from the reservoir 300 into the mixing unit. The outlet channel serves to discharge the gas 530 from the mixing unit 200 into the reservoir 300, which is displaced by the monomer liquid 510 flowing into the distal part 217 of the interior space 215. In order to ensure a good mass transfer between reservoir 300 and mixing unit 200, the outlet channel 410 in the embodiment shown has a minimal

[0129] Outlet channel diameter 411, which corresponds to a minimum inlet channel diameter 401 of the inlet channel 400. The inlet channel 400 is shaped as a funnel at an end facing the ampoules 330 in order to be able to better absorb the monomer liquid 510 when it flows out of the ampoules 330 to be opened.

[0130] Both the inlet channel 400 and the outlet channel 410 are formed in two parts, with a part of the inlet channel 400 and the outlet channel 410 facing the mixing unit 200 each being formed as a passage in the cartridge 210, and a part of the inlet channel 400 and the outlet channel 410 facing the ampoules 330 each extending within the reservoir 300, which can be reversibly separated from the mixing unit 200. The inlet channel 400 and the outlet channel 410 are thus formed from two components of the device 100.

[0131] The device 100 further comprises a closure element 450 in the form of a screw, which, after separation of the mixing unit 200 and the reservoir 300, can close the part of the inlet channel 400 and the outlet channel 410 facing the mixing unit 200, i.e. the passages in the cartridge 210, in a fluid-conducting manner (cf. Figure 6 ).

[0132] Figure 2 shows the device 100 from Figure 1 , wherein the first form fit 430, the second form fit 440 and a pivot point 420, around which the ampoules 330 can be tilted against the connection 350 due to the deformable region 320 (cf. Figure 1 ) are pressed, are indicated by filled circles.

[0133] The first form fit 430 is formed by the components which comprise the inlet channel 400 and the outlet channel 410 (cf. Figure 1 ) in the area of ​​the inlet channel 400 and the outlet channel 410. The second form fit 430 is formed by a clip (not shown in Figure 1 and 2 ; cf. Figure 3 ) trained.

[0134] In the side view of the device 100 shown, the first positive connection 430, the second positive connection 440, and the pivot point 420 form a triangle (indicated by connecting lines between the filled circles). If the ampoules 330 are tilted about the pivot point 420, so that the ampoules 330, in particular the ampoule heads 332 (cf. Figure 1 ), against the connection 350 (cf. Figure 1 ), the force required to open the ampoules 330 in a fluid-conducting manner is distributed between the first positive locking element 430 and the second positive locking element 440. The triangular arrangement of the first positive locking element 430, the second positive locking element 440, and the pivot point 420 achieves an advantageous force distribution. In particular, this can reduce the risk of the inlet channel 400 and the outlet channel 410 kinking or breaking off.

[0135] The first positive locking element 430, the second positive locking element 440, and the pivot point 420 are arranged relative to one another such that the second positive locking element 440 is at a shorter distance from the first positive locking element 430 than the pivot point 420. The pivot point 420 and the first positive locking element 430 are thus spaced further apart than the first positive locking element 430 and the second positive locking element 440. This ensures improved distribution of the force required when tilting to open the ampoules 330 about the pivot point 420 between the two positive locking elements 430, 440, while simultaneously ensuring the most space-saving design of the device 100 possible. The latter particularly facilitates handling of the device 100 by a user.

[0136] The first positive connection 430 lies on a straight line 431 running parallel to a longitudinal axis 213 of the cartridge 210, the second positive connection 440 lies on a further straight line 441 running parallel to the longitudinal axis 213 of the cartridge 210, and the pivot point 420 lies on a further straight line 421 running parallel to the longitudinal axis 213 of the cartridge 210. The straight lines 431, 441, 421 all have different straight line distances from the longitudinal axis 213 of the cartridge 210. In the embodiment shown, the straight line distance between the straight line 421 through the pivot point 420 and the longitudinal axis 213 is the greatest, followed by the straight line distance between the straight line 431 through the first positive connection 430 and the longitudinal axis 213.The different straight line spacings improve the distribution of the force required when tilting to open the ampoules 330 around the pivot point 420 to the two form-locking elements 430, 440 and at the same time allow the device 100 to be designed in the most space-saving way possible. The latter particularly facilitates the handling of the device 100 by a user.

[0137] Figure 3 shows a perspective side view of the mixing unit 200 of the device 100 from the Figures 1 and 2 . The mixing unit 200 has two clip protrusions 261 on an outer side of the cartridge 210, which can be reversibly inserted into clip notches on an outer surface of the reservoir 300 (not shown) in order to form a clip (not shown) which provides the second form fit (cf. Figure 2 ) is formed.

[0138] Figure 4 shows the device 100 from the Figures 1 to 3 with around the pivot point 420 (cf. Figure 2) tilted ampoules 330. For this purpose, the reservoir container 310 is bent at the deformable area 320 so that the ampoule heads 332 are pressed against the connection 350 and the ampoules 330 in the area of ​​the ampoule neck 332 (cf. Figure 1) were opened in a fluid-conducting manner. The monomer liquid 510 stored in the fluid-conductingly opened ampoules 330 has already largely flowed out of the ampoules 330 via the cavity 340 and the inlet channel 400 into the distal part 217 of the interior space 215. The ampoule head 332 of one of the ampoules 330 has completely passed from the connection 350 into the cavity 340. In doing so, the ampoule head 332 was caught by the filter element 345, so that it, or fragments thereof, cannot reach or through the inlet channel 400. The cavity 340 is dimensioned such that the ampoule head 332 can be mounted in it in a fully rotatable manner, so that any monomer liquid 510 still present in the ampoule head 332 after opening the ampoule 330 can flow out into the cavity 340. This is in Figure 4This has already happened. At the same time, a portion of the gas 530 has been discharged from the interior space 215 via the outlet channel 410 into the reservoir 300. The volume of the discharged portion of the gas 530 essentially corresponds to the volume of the monomer liquid 510 already introduced into the distal portion 217 of the interior space 215.

[0139] In order to convey the monomer liquid 510 essentially completely through the inlet channel 400, and not via the outlet channel 410, into the mixing unit 200, the inlet channel 400 has a smaller distance from the pivot point 420 than the outlet channel 410. Furthermore, the outlet channel 410 opens into the interior space 215 proximal to the inlet channel 400, so that the inflowing monomer liquid 510 does not hinder the discharge of the gas 530 from the interior space 215 through the outlet channel 410.

[0140] Figure 5 shows the device 100 from the Figures 1 to 4, wherein the reservoir 300 was separated from the mixing unit 200 by releasing the first positive connection 430 and the second positive connection 440 after the monomer liquid 510 had essentially completely flowed into the distal part 217 of the interior space 215. By separating the reservoir 300, the parts of the inlet channel 400 and the outlet channel 410 facing the reservoir 300 were fluidly separated from the parts of the inlet channel 400 and the outlet channel 410 facing the mixing unit 200. The inlet channel 400 and the outlet channel 410 are thus located in a fluidly separated second channel position.

[0141] The distal part 217 of the interior space 215 is fluidly connected to the surroundings of the device 100 via the part of the inlet channel 400 and the outlet channel 410 facing the mixing unit 200, i.e., the passages in the cartridge 210. In the illustrated embodiment of the device 100, advancing the delivery piston 240 toward the discharge piston 220 would thus at least partially discharge the monomer liquid 510 from the mixing unit 200, instead of conveying it, as desired, essentially completely through the conduit 230 into the proximal part 216 of the interior space 215, where it forms the bone cement dough together with the bone cement powder 500.

[0142] Figure 6 shows the device 100 from the Figures 1 to 6, wherein the closure element 450 is screwed in until it contacts the cartridge 210 and has thus been moved into a closed position in which the part of the inlet channel 400 and the outlet channel 410 facing the mixing unit 200 is fluidly sealed from the environment of the device 100. In the closed position, the closure element 450 enables a substantially complete conveyance of the monomer liquid 510 into the proximal part 216 of the interior space by advancing the delivery piston 240 in the direction of the discharge piston 220.

[0143] In order to facilitate the conveyance of the monomer liquid 510 into the proximal part 216 of the interior space 215 for the user, the distal cartridge end 212 is connected to a discharge aid 550 in the form of a discharge gun, which can press distally against the delivery piston 240 in order to displace it proximally.

[0144] Figure 7 shows the device 100 from the Figures 1 to 6when conveying the monomer liquid 510 from the distal part 217 of the interior space 215 through the conduit means 230 into the proximal part 216 of the interior space 215. Due to the closure means 450 in the closure position, no monomer liquid 510 is released from the distal part 217 of the interior space 215 into the environment of the device 100.

[0145] As the monomer liquid 510 begins to come into contact with the bone cement powder 500, the bone cement dough begins to form in the proximal portion 216 of the interior space 215. The hydrophilic additive in the bone cement powder 500 ensures improved distribution of the monomer liquid 510 in the bone cement powder 500, allowing the preparation of a homogeneous bone cement dough without mechanical aids, such as a mixing rod, and thus without the need for a mixing device.

[0146] Figure 8 shows the device 100 from the Figures 1 to 7with bone cement dough 520 provided in the proximal part 216 of the interior space 215. For this purpose, the delivery piston 240 was displaced proximally by the discharge aid 550 until it rests distally against the discharge piston 220. This essentially completely conveyed the monomer liquid 510 into the proximal part 216 of the interior space 215.

[0147] The formation of the bone cement paste 520 caused the bone cement powder 500 to swell, resulting in an increase in volume. As a result, the plug 265 was ejected from the closure cap 260 in sections, signaling to the user of the device 100 that the bone cement paste 520 was ready.

[0148] Figure 9 shows the device 100 from the Figures 1 to 8when discharging the bone cement dough 520 from the discharge opening 250. For this purpose, the feed piston 240 together with the discharge piston 220 was advanced by a continued advance of the discharge aid 550 in the direction of the discharge opening 550. In another embodiment of the device 100, not shown, the discharge opening 250 can be provided with a discharge snorkel to support the targeted discharge of the bone cement 520.

[0149] Figure 10 shows a further exemplary embodiment of a device 100' for providing a bone cement dough from two starting components in an initial state. The embodiment of the device 100' largely corresponds to the one described above and in the Figures 1 to 9 illustrated embodiment, so that to avoid repetition, reference is made to the above description. Modifications of a variant of the Figures 1 to 9shown embodiment have the same reference numeral with an apostrophe.

[0150] The device 100' differs from the device 100 of the Figures 1 to 9 by a closure element 450' in the form of a rotary valve. The inlet channel 400' and the outlet channel 410' are, as in the device 100 of the Figures 1 to 9 , designed in two parts, wherein the part of the two channels 400', 410' facing the mixing unit 200' extends through the closure element 450'. In Figure 10 the closure element 450' is in a first rotary valve position, so that the inlet channel 400' and the outlet channel 410' are in the first channel position, which fluidically connects the reservoir 300' and the mixing unit 200'.

[0151] Figure 11 shows the device 100' from Figure 10with fluid-conducting open ampoules 330'. For this purpose, the reservoir container 310' is bent at the deformable region 320', so that the ampoule heads 332' are pressed against the connection 350' and the ampoules 330' in the region of the ampoule neck 332' (cf. Figure 10) were opened in a fluid-conducting manner. The monomer liquid 510' stored in the fluid-conductingly opened ampoules 330' has already largely flowed out of the ampoules 330' via the cavity 340' and the inlet channel 400' into the distal part 217' of the interior space 215'. The ampoule head 332' of one of the ampoules 330' has completely passed from the connection 350' into the cavity 340'. In doing so, the ampoule head 332' was caught by the filter element 345', so that it, or fragments thereof, cannot reach or through the inlet channel 400'. The cavity 340' is dimensioned such that the ampoule head 332' can be mounted in a fully rotatable manner, so that any monomer liquid 510' still present in the ampoule head 332' after the ampoule 330' has been opened can flow out into the cavity 340'. This is Figure 11This has already happened. At the same time, a portion of the gas 530' has been discharged from the interior space 215' via the outlet channel 410' into the reservoir 300'. The volume of the discharged portion of the gas 530' essentially corresponds to the volume of the monomer liquid 510' already introduced into the distal portion 217' of the interior space 215'.

[0152] In order to convey the monomer liquid 510' substantially completely through the inlet channel 400', and not via the outlet channel 410', into the mixing unit 200', the inlet channel 400' is located at a shorter distance from the pivot point 420' than the outlet channel 410'. Furthermore, in the first rotary valve position, the outlet channel 410' opens into the interior space 215' proximal to the inlet channel 400', so that the inflowing monomer liquid 510' does not impede the discharge of the gas 530' from the interior space 215' through the outlet channel 410'.

[0153] Figure 12 shows the device 100' from the Figures 10and 11 with monomer liquid 510' essentially completely conveyed into the distal part 217' of the interior space 215'. In order to facilitate essentially complete conveyance of the monomer liquid 510' from the distal part 217' of the interior space 215' of the illustrated embodiment of the device 100', the closure element 450' in the form of a rotary valve has been moved into a second rotary valve position by a rotation of 90° about an axis of the closure element 450'. The inlet channel 400' and the outlet channel 410' are located in the second rotary valve position in a second channel position, in which the mixing unit 200' and the reservoir 300' are fluidically separated from one another. The conveyance of the monomer liquid 510' into the proximal part 216' of the interior space 215' as well as the provision and discharge of the bone cement dough can be carried out analogously to the device 100 as shown in the Figures 7 to 9 shown.

[0154] Figure 13shows a method 600 for providing a bone cement dough 520 from two starting components by means of the devices 100, 100' according to the Figures 1 to 9 and 10 to 12 comprising steps 610 and 620 and optionally step 615.

[0155] In a step 610, the monomer liquid 510, 510' flows from the reservoir 300, 300' through the inlet channel 400, 400' into the distal part 217, 217' of the interior space 215, 215' of the mixing unit 200, 200'. At the same time, the monomer liquid 510, 510' flowing into the distal part 217, 217' of the interior space 215, 215' displaces, according to its volume, the gas 530, 530' present in the interior space 215, 215', which is discharged from the interior space 215, 215' into the reservoir simultaneously with the inflow of the monomer liquid 510, 510'. The inlet channel 400, 400' thus interacts synergistically with the outlet channel 410, 410' to improve mass transfer between the reservoir 300, 300' and the mixing unit 200, 200'.

[0156] In a step 620, the monomer liquid 510, 510' is conveyed from the distal part 217, 217' of the interior space 215, 215' through the conduit 230, 230' into the proximal part 216, 216' of the interior space 215, 215'. For this purpose, the delivery piston 240, 240' is advanced toward the discharge piston 220, 220' within the interior space 215, 215'. In order to convey the monomer liquid 510, 510' substantially completely into the proximal part 216, 216' of the interior space 215, 215', the delivery piston 240, 240' is preferably advanced in the direction of the discharge piston 220, 220' until it rests distally against the discharge piston 220, 220'.

[0157] In a preferred embodiment of the method 600, in a step 615, which takes place between step 610 and step 620, the part of the two-part inlet channel 400, 400' and the two-part outlet channel 410, 410' facing the mixing unit 200, 200' is fluidically closed by the closure element 450, 450'. This facilitates a substantially complete conveying 620 of the monomer liquid 510, 510' into the proximal part 216, 216' of the interior space 215, 215', since the monomer liquid 510, 510' cannot be accidentally forced out of the corresponding parts of the channels 400, 400' by advancing the conveying piston 240, 240'. 410, 410' can be discharged from the device 100, 100'.

[0158] Preferably, before step 620, the reservoir 300, 300' is separated from the mixing unit 200, 200' by releasing the first form fit 430 and the second form fit 440, which improves the handling of the device for a user.

[0159] With the conveyance 620 of the monomer liquid 510, 510' into the proximal part 216, 216' of the interior space 215, 215', the bone cement dough 520 is formed from the bone cement powder 500, 500' and the monomer liquid 510, 510'. Preferably, the formation of the bone cement dough 520 takes place without mechanical action by the user of the device 100, 100'. The method 600 is thus preferably carried out without mechanical action, for example, without actuating a mixing device, such as a mixing rod.

[0160] After the bone cement dough 520 has been provided, it is preferably discharged from the device 100, 100', in particular from the proximal part 216, 216' of the interior 215, 215', by continuously advancing the delivery piston 240, 240' in the direction of the discharge opening 250, 250'. The delivery piston 240, 240' acts from the distal direction on the discharge piston 220, 220', which is then moved in the direction of the discharge opening 250, 250'. The delivery 620 of the monomer liquid 510, 510' and the discharge of the bone cement dough 520 thus preferably occur by means of a unidirectional advance of the delivery piston 240, 240'. Reference symbol

[0161] 100, 100'Device 200. 200'Mixing unit 210, 210'Hollow cylindrical cartridge 211, 211'Proximal cartridge end 212, 212'Distal cartridge end 213Longitudinal axis of the cartridge 215, 215'Interior of the cartridge 216, 216'Proximal part of the interior 217, 217'Distal part of the interior 220, 220'Discharge piston 230, 230'Conduit means 235, 235'Filter medium 240, 240'Feed piston 250, 250'Discharge opening 260, 260'Closing cap 265, 265'Plug 300, 300' reservoir 310, 310' reservoir container 320, 320' deformable area 330, 330' ampoule 331, 331' ampoule body 332, 332' ampoule head 333, 333' ampoule neck 340, 340' cavity 345, 345' filter element 350, 350' connection 355, 355' connection diameter 361 clip protrusions 400, 400' inlet channel 401, 401' inlet channel diameter 410, 410' outlet channel 411,411'Outlet channel diameter 420Pivot point 421Straight line through the pivot point 430First mold closure 431Straight line through the first mold closure 440Second mold closure 441Straight line through the second mold closure 450, 450'Closing element 500, 500'Bone cement powder 510, 510'Monomer liquid 520Bone cement dough 530, 530'Gas 550, 550'Discharge aid 600Process 610Flow 615Closing 620Conveying,

Claims

1. A device (100, 100') for preparing a bone cement paste (520) from two starting components, the device comprising a mixing unit (200, 200') comprising a hollow cylindrical cartridge (210, 210') with an interior space (215, 215'), wherein a discharge piston (220, 220') which is axially movable in the interior space (215, 215') is arranged in the interior space (215, 215'), which discharge piston divides the interior space (215, 215') into a proximal part (216, 216') of the interior space (215, 215') and a distal part (217, 217') of the interior space (215, 215'), wherein the proximal part (216, 216') and the distal part (217, 217') of the interior space (215, 215') are fluidically connected to one another via a conduit means (230, 230'), wherein a bone cement powder (500, 500') is stored as the first starting component in the proximal part (216, 216') of the interior space (215, 215'), and wherein a delivery piston (240, 240') which is axially movable in the interior space (215, 215') is arranged in the distal part (217, 217') of the interior space (215, 215'), and a reservoir (300, 300') for a monomer liquid (510, 510') as the second starting component, which reservoir is or can be fluidically connected via an inlet channel (400, 400') to the distal part (217, 217') of the interior space (215, 215') in order to introduce the monomer liquid (510, 510') from the reservoir (300, 300') into the mixing unit (200, 200'), wherein the reservoir (300, 300') and the mixing unit (200, 200') are or can be fluidically connected via an outlet channel (410, 410'), via which a gas (530, 530') can be discharged from the interior space (215, 215') into the reservoir (300, 300'), wherein the inlet channel (400, 400') and the outlet channel (410, 410') are formed at least in two parts, so that the mixing unit (200, 200') and the reservoir (300, 300') are fluidically connected to one another in a first channel position of the inlet channel (400, 400') and the outlet channel (410, 410') and are fluidically separated from one another in a second channel position of the inlet channel (400, 400') and the outlet channel (410, 410'), wherein the device (100, 100') comprises a closure element (450, 450') which fluidically closes or makes closable at least a part of the two-part inlet channel (400, 400') and the two-part outlet channel (410, 410') that faces the mixing unit (200, 200'), characterized in that the closure element (450') is a rotary valve through which the part of the two-part inlet channel (400') and the two-part outlet channel (410') that faces the mixing unit (200') extends and which, in a first rotary valve position, leaves the inlet channel (400) and the outlet channel (410') in the first channel position and, by rotating into a second rotary valve position, moves the inlet channel (400') and the outlet channel (410') into the second channel position.

2. A device (100, 100') for preparing a bone cement paste (520) from two starting components, the device comprising a mixing unit (200, 200') comprising a hollow cylindrical cartridge (210, 210') with an interior space (215, 215'), wherein a discharge piston (220, 220') which is axially movable in the interior space (215, 215') is arranged in the interior space (215, 215'), which discharge piston divides the interior space (215, 215') into a proximal part (216, 216') of the interior space (215, 215') and a distal part (217, 217') of the interior space (215, 215'), wherein the proximal part (216, 216') and the distal part (217, 217') of the interior space (215, 215') are fluidically connected to one another via a conduit means (230, 230'), wherein a bone cement powder (500, 500') is stored as the first starting component in the proximal part (216, 216') of the interior space (215, 215'), and wherein a delivery piston (240, 240') which is axially movable in the interior space (215, 215') is arranged in the distal part (217, 217') of the interior space (215, 215'), and a reservoir (300, 300') for a monomer liquid (510, 510') as the second starting component, which reservoir is or can be fluidically connected via an inlet channel (400, 400') to the distal part (217, 217') of the interior space (215, 215') in order to introduce the monomer liquid (510, 510') from the reservoir (300, 300') into the mixing unit (200, 200'), wherein the reservoir (300, 300') and the mixing unit (200, 200') are or can be fluidically connected via an outlet channel (410, 410'), via which a gas (530, 530') can be discharged from the interior space (215, 215') into the reservoir (300, 300'), wherein the inlet channel (400, 400') and the outlet channel (410, 410') are formed at least in two parts, so that the mixing unit (200, 200') and the reservoir (300, 300') are fluidically connected to one another in a first channel position of the inlet channel (400, 400') and the outlet channel (410, 410') and are fluidically separated from one another in a second channel position of the inlet channel (400, 400') and the outlet channel (410, 410'), wherein the device (100, 100') comprises a closure element (450, 450') which fluidically closes or makes closable at least a part of the two-part inlet channel (400, 400') and the two-part outlet channel (410, 410') that faces the mixing unit (200, 200'), wherein the mixing unit (200, 200') and the reservoir (300, 300') are or can be reversibly connected to one another via a first form fit (430), characterized in that the closure element (450) can be brought into a closure position after separation of the reservoir (300) from the mixing unit (200) by releasing the first form fit (430), in order to fluidically close the part of the two-part inlet channel (400) and the two-part outlet channel (410) that faces the mixing unit (200).

3. The device (100, 100') according to claim 1 or 2, wherein the reservoir (300, 300') comprises a reservoir container (310, 310') in which at least one fluidically closed ampule (330, 330') with an ampule body (331, 331') and an ampule head (332, 332') is arranged, and the monomer liquid (510, 510') is stored in the ampule (330, 330'), and comprises a cavity (340, 340') in the region of the ampule head (332, 332'), wherein the cavity (340, 340') is fluidically connected to the inlet channel (400, 400') and comprises a connection (350, 350') to the ampule (330, 330'), wherein the ampule head (332, 332') is arranged at least partially in the connection (350, 350'), and the reservoir container (310, 310') comprises a deformable region (320, 320') at least in portions, so that tilting of the ampule (330, 330') about a pivot point (420) against the connection (350, 350') is possible.

4. The device (100, 100') according to claim 3, wherein the inlet channel (400, 400') has a smaller distance from the pivot point (420) than the outlet channel (410, 410').

5. The device (100, 100') according to any of the preceding claims, wherein the outlet channel (410, 410') opens into the interior space (215, 215') proximally to the inlet channel (400, 400').

6. The device (100, 100') according to any of the preceding claims, wherein the inlet channel (400, 400') is designed as a funnel at an inlet channel end opposite the mixing unit (200, 200').

7. The device (100, 100') according to any of the preceding claims, wherein the outlet channel (410, 410') has a minimum outlet channel diameter (411, 411') which corresponds to at least half the minimum inlet channel diameter (401, 401') of the inlet channel (400, 400').

8. The device (100, 100') according to claim 1, wherein the mixing unit (200, 200') and the reservoir (300, 300') are or can be reversibly connected to one another via a first form fit (430).

9. The device (100) according to any of claims 2 to 7, wherein the closure element (450) is a screw.

10. The device (100, 100') according to any of claims 2 to 8, wherein the mixing unit (200, 200') and the reservoir (300, 300') are or can be reversibly connected to one another via a second form fit (440).

11. A method (600) for preparing a bone cement paste (520) from two starting components by means of a device (100, 100') according to any of the preceding claims, comprising the steps of: a. the monomer liquid (510, 510') flowing (610) from the reservoir (300, 300') through the inlet channel (400, 400') into the distal part (217, 217') of the interior space (215, 215') while a gas (530, 530') is simultaneously discharged from the interior space (215, 215') through the outlet channel (410, 410') into the reservoir (300, 300'), b. the monomer liquid (510, 510') being conveyed (620) from the distal part (217, 217') of the interior space (215, 215') through the conduit means (230, 230') into the proximal part (216, 216') of the interior space (215, 215') by means of advancement of the delivery piston (240, 240') in the direction of the discharge piston (220, 220').

12. The method (600) according to claim 11 by means of a device (100, 100') according to any of claims 1 to 10, wherein, before the conveying (610) of the monomer liquid (510, 510') in step b., the part of the two-part inlet channel (400, 400') and the two-part outlet channel (410, 410') that faces the mixing unit (200, 200') is fluidically closed (615) by the closure element (450, 450').