Device for mixing bone cement

Abstract

To provide a device for storing and / or mixing bone cement.SOLUTION: A device (10) for mixing bone cement comprises: a first hollow body (11) which encloses a first cavity (12) for receiving a powder (14) and has a first opening (15); and a second hollow body (21) which encloses a second cavity for receiving an ampoule (24) and has a second opening (25). The first hollow body (11) and the second hollow body (21) are connectable to each other in such a way that the first opening (15) and the second opening (25) are fluidically connected to each other. The first hollow body (11) is elastic, so that the content of the first hollow body (11) can be mixed from the outside by kneading.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a device for storing and / or mixing bone cement.

[0002] Bone cements are usually produced by mixing a powder with a liquid. For example, polymethylmethacrylate (PMMA) bone cements are known, which are composed of a liquid monomer component and a powder component. The monomer component generally contains the monomer methylmethacrylate and in particular an activator dissolved therein, for example N,N-dimethyl-p-toluidine. The powder component, also called bone cement powder, has one or more polymers produced by polymerization, preferably suspension polymerization, based on methylmethacrylate and comonomers such as styrene, methylacrylate or similar monomers, and in particular a radiopaque agent and / or an initiator dibenzoyl peroxide. When the powder component is mixed with the monomer component, a plastically deformable dough, the actual bone cement, is produced, for example by the polymers of the powder component expanding in the methylmethacrylate. When the powder component is mixed with the monomer component, the activator, for example N,N-dimethyl-p-toluidine, reacts with the dibenzoyl peroxide to form radicals. The radicals formed can initiate the radical polymerization of methylmethacrylate. As the polymerization of the methyl methacrylate progresses, the viscosity of the cement paste may increase until it hardens.

[0003] Polymethylmethacrylate bone cement can be mixed in a suitable mixing beaker with a spatula by mixing the cement powder with the monomer liquid. Air bubbles can be trapped in the bone cement dough, which can adversely affect the mechanical properties of the hardened bone cement. Other drawbacks are the need to manually measure quantities and proper mixing, which is not always assured.

[0004] To avoid air inclusions in the bone cement dough, vacuum cementing systems are known, for example from US Pat. No. 6,033,105 (A), US Pat. No. 5,624,184 (A) or US Pat. No. 4,671,263 (A). Here, a vacuum must be applied. A further development in cementing technology is represented by cementing systems in which both the cement powder and the monomer liquid are already packaged in separate compartments and mixed together immediately before the cement application in the cementing system. Such closed, completely prepacked mixing systems are described in EP 0 380 867 (B1), EP 0 796 653 (B1) or EP 0 692 229 (B1).

[0005] Mixing devices in which an outer device for squeezing out the bone cement is used are disclosed in WO 9416951 A1, EP 1741413 B1, EP 3054880 B1 and DE 19718648 A1. Mixing devices in which a vacuum is applied to allow the transfer or mixing of the components or bone cement are known from DE 102009031178 B3, US 8662736 B2 and EP 3093067 B1. EP 2393456 B1 describes a mixing device in which a liquid is forced into the powder by overpressure. Summary of the Invention [Problem to be solved by the invention]

[0006] It is an object of the present invention to provide a particularly simple and cost-effective device for mixing the components for producing a bone cement and for dispensing the produced bone cement. In particular, it is an object of the present invention to at least partially overcome the drawbacks known from the prior art.

[0007] This object is achieved by a device for mixing bone cement according to claim 1. Advantageous embodiments are defined in the dependent claims.

[0008] To achieve the above object, a device for mixing bone cement is used. It comprises a first hollow body surrounding a first cavity for receiving a powder and having a first opening. The device further comprises a second hollow body surrounding a second cavity for receiving an ampoule and having a second opening. The first hollow body and the second hollow body are connectable to each other such that the first opening and the second opening are fluidly connected to each other. Since the first hollow body has elasticity, the contents of the first hollow body can be mixed from the outside by kneading.

[0009] By kneading, the components can be mixed from the outside particularly easily and without additional devices. No mixing rods or the like are required, which significantly reduces the technical effort and the susceptibility of errors. The device is very robust. In the simplest case, only two parts are required, which can also be produced cost-effectively. Handling is very easy and less susceptible to errors.

[0010] The elasticity of the first hollow body typically allows it to be compressed, so that, for example, gas, e.g. air, present in the first hollow body can be pushed out. In this way, the volume of the first cavity changes during mixing, and a particularly good mixing can be achieved. For example, gas present in the first cavity can be temporarily or permanently pushed into the second cavity.

[0011] The hollow body is a body having a wall surrounding at least one cavity. The cavity may be open or closed. The first hollow body may be elastomeric and / or made from rubber. The first hollow body may also be called an ampoule holder.

[0012] The second opening is permeable to at least liquids. In particular, the second opening is permeable to gases and liquids. The term "gas" refers in this application only to the aggregated state and also includes gas mixtures such as air. The second opening is dimensioned such that it is not possible for the ampoule to pass through the second opening. The first opening is designed in particular to allow the powder to be introduced into the first cavity through the opening and / or to allow the mixture produced, in particular bone cement, to leave the first cavity through the opening.

[0013] A fluid connection of a first opening to a second opening means a connection such that liquid or gas can flow from the surrounding environment from the first opening to the second opening, and in particular can also flow back.

[0014] Kneading from the outside typically serves to mix liquid and powder components to produce bone cement. In particular, manual kneading is meant. During kneading, for example, one or more areas of the first hollow body can be alternately compressed and released. It is also possible to gradually apply pressure to different positions of the first hollow body. In particular, the first hollow body is elastic, so that it is possible to temporarily reduce the outer diameter of the first hollow body by 50%, in particular 70%, with respect to its unloaded size. Due to the elasticity, the first hollow body at least essentially takes on its original size after the application of the external force has ceased.

[0015] The first hollow body can be designed such that the generated bone cement can be pushed out manually by applying a manual force from the outside. In this way, it is possible to dispense the bone cement without additional devices for applying force or for generating pressure or negative pressure.

[0016] In one embodiment, the second hollow body further comprises a third opening through which the gas can flow out of the second hollow body. If the first hollow body contains gas, the gas can be forced out of the first hollow body through the second hollow body and the third opening and thus forced out of the device. This can typically be done by applying a manual compressive force to the first hollow body. When the external force stops, a negative pressure can be created in the first hollow body, during which liquid, in particular liquid exiting the ampoule, is sucked from the second cavity into the first cavity. Compared to the pressure on the liquid, this ensures that the liquid only reaches the desired destination when it is transported to the destination by suction. Thus, even if there is a defect, the liquid cannot be pressed elsewhere.

[0017] For suction, it is not necessary to apply an external vacuum. Therefore, the costs on the equipment in use can be minimized and the application is therefore independent of the presence of an external vacuum pump. No pump piston is required to convey the monomer liquid to the cement powder.

[0018] The third opening is particularly arranged at the end facing away from the second opening, preferably at the end opposite to the second opening. When the gas is being pushed out, the device can be held so that the third opening faces upwards. Thus, the gas located in the first cavity can be pushed out completely. This allows the maximum negative pressure to be generated, which allows the maximum amount of liquid to flow into the first cavity.

[0019] The third opening can be closed, for example, with a gas-permeable closure, for example a gas-permeable cap. In this way, the ingress of contaminants is prevented. The third opening is particularly dimensioned such that it is not possible for the ampoule to pass through the third opening.

[0020] In particular, the third opening is configured in such a way that a gas flow in both directions is possible. In this way, sterilization with a gas such as ethylene dioxide is easily possible. In particular, sterilization can be carried out with the two hollow bodies connected. In this case, the gas can reach and penetrate the powder and can also sterilize it.

[0021] Preferably, the first hollow body is configured to exert a restoring force against the deformation after deformation, in this way kneading for mixing is easier compared to, for example, a flexible bag, since the first hollow body only needs to be compressed and the outward movement is automatically achieved by the restoring force.

[0022] The force required for the elastic deformation of the first hollow body is preferably smaller than the force required for the elastic deformation of the second hollow body. In this way, it is ensured that when the two hollow bodies are connected and a negative pressure is generated by pressing the first hollow body together, liquid is sucked from the second hollow body into the first hollow body. Deformation of the second hollow body is prevented and the sucking of liquid into the first hollow body is prevented. For example, this can be achieved by a smaller wall thickness of the first hollow body compared to the second hollow body and / or by a softer or more plastic material of the first hollow body.

[0023] In one embodiment, the second hollow body is at least partially elastic such that the second hollow body can be bent from the outside to break open an ampoule disposed in the second cavity.

[0024] In particular, the second ampoule is broken open at its predetermined breaking point. Such ampoules are usually made of glass and / or have an ampoule body integrally connected to a head. The head can be detached from the body by breaking, so that the substance, in particular the liquid, contained in the ampoule is released. In particular, this means breaking by hand. Preferably, a molding element is provided on the second hollow body in the region of the predetermined breaking point, on which molding element the position of the predetermined breaking point can be seen from the outside.

[0025] In particular, the wall of the second hollow body in the region of the predefined breaking point is particularly bendable compared to other points of the wall of the second hollow body. This can be easily achieved, for example, by locally thinning the wall thickness. In other words, the second hollow body in this case has a predefined snap point at which a snap is realized when a force, in particular a manual force, is applied from the outside. In this way, a particularly simple and almost error-free opening of the ampoule can be made possible.

[0026] In one embodiment, the device is designed so that the head of the ampoule faces the second opening, so liquid does not have to flow through the body of the ampoule to exit the second opening.

[0027] In one embodiment, the second hollow body comprises a filter element arranged such that the flow passing through the second opening is filtered.

[0028] A filter element is an element that allows the filtration of a medium in order to remove particles from the medium. A filter element can be designed, for example, as a sieve or as a packed bed of material, in particular a porous material.

[0029] The flow through the second opening may be, for example, a gas flow, a liquid flow, a solid flow, for example a powder, or any mixture of the above examples. The filter element may, for example, prevent powder from entering the second cavity, glass shards from escaping the second cavity, and / or generated bone cement from entering the second cavity.

[0030] In particular, the filter element is arranged in the region of the outer end of the second hollow body. For example, the filter element closes the second opening substantially flush. In this case, a deviation of a few millimeters can be tolerated. This makes it possible to completely prevent the ingress of substances into the second hollow body. In addition, the filter element is particularly easy to install.

[0031] In one embodiment, the device includes an ampoule received or receivable in the second cavity. Typically, the volume of the first cavity essentially corresponds to the volume of the ampoule. In other words, the cavity is at least essentially completely filled when the ampoule is placed in the cavity. Typically, the inner contour of the second cavity at least essentially corresponds to the outer contour of the ampoule. In particular, the ampoule contains a liquid, for example for the manufacture of bone cement. The ampoule can contain, for example, a monomer.

[0032] In one embodiment, the device comprises a powder received or receptive in the first cavity. In particular, a powder for producing bone cement, preferably a polymethylmethacrylate bone cement powder. In particular, the first hollow body is only partially filled with the powder. This facilitates mixing, since a better mobility of the components and mixtures to be mixed is achieved. For example, a volume fraction of more than 30%, preferably more than 40%, in one embodiment about 50% or more, and / or less than 75%, preferably less than 60%, of the first cavity is filled with the powder. In particular, the remaining volume of the first cavity is filled with gas.

[0033] If the device contains not only ampoules with liquid but also powder, in other words filled ready for use, the device can also be called a completely prepacked mixing system. It can therefore be used immediately for the production of bone cement. The device serves in particular to store the two components, to mix and to discharge the bone cement, in particular polymethylmethacrylate bone cement.

[0034] In one embodiment, the first cavity has a volume that corresponds at least to the sum of the volume of the powder and the volume of the liquid received or receivable in the ampoule. In this way, a sufficient volume is available to achieve a good movement of the mixture present in the first cavity and thus a good mixing of the components. Thus, a good quality of the bone cement can be achieved.

[0035] Preferably, the volume of the first cavity corresponds to at least the sum of the volume of the powder and twice the volume of the liquid that can be accommodated in the ampoule. In this way, mixing can be further simplified and at the same time a particularly high quality of the bone cement can be ensured. In one embodiment, the volume of the first cavity corresponds to at least the sum of the volume of the powder and the volume of the second cavity.

[0036] In one embodiment, the second cavity has a body region for receiving the body of the ampoule and / or a head region for receiving the head of the ampoule. In particular, the inner contour of the body region at least substantially corresponds to the outer contour of the body of the ampoule. The inner contour of the body region can have, for example, a cylindrical cross section. In particular, the inner contour of the head region at least substantially corresponds to the outer contour of the head of the ampoule. A transition region may be provided between the body region and the head region, in which the edges and / or transitions may be formed rounded. The body region and the head region are connected to each other such that a closed and filled ampoule can be accommodated in the second cavity.

[0037] In one embodiment, at least one first fluid connection is present between the end of the body region facing the head region and the second opening. In this way, even if the head region and the possible second fluid connection therein are blocked or clogged, for example by a broken head of the ampoule and / or glass fragments, liquid from the body of the ampoule can flow out of the second hollow body and / or be sucked out of the second hollow body. Typically, the amount of powder is dimensioned such that only the amount of liquid in the intended use position above the connection of the second fluid connection is required for the production of bone cement.

[0038] In one embodiment, the second fluid connection is between the end of the head region facing away from the body region and the second opening. In this way, liquid from the ampoule can flow out of the second hollow body and / or can be sucked out of the second hollow body. For example, a first flow duct forming the first fluid connection extends between the end of the head region facing away from the body region and the second opening.

[0039] For example, at least one second flow duct forming a second fluid connection extends between the end of the body region facing the head region and the first flow duct. In this case, for example, the lower region of the flow duct connected to the second opening serves as the first and second fluid connection. The first flow duct to the body portion can connect a branch that is redirected from the second flow duct to the head portion or vice versa. In other words, the first and second fluid connections can partially correspond. In one embodiment, two second fluid connections are provided. These are in particular identical and / or designed as the second flow ducts as described.

[0040] In one embodiment, the second hollow body encloses two second cavities, each of which is adapted to receive an ampoule. In particular, a common second opening is provided through which liquid can flow out of the two ampoules from the second hollow body. Typically, each second cavity has a separate opening, to which a respective flow duct is connected. The flow ducts may in particular merge inside the second hollow body to form a single flow duct, which is connected to a common second opening. Alternatively, there are two second hollow bodies, in particular connected to each other, each enclosing a cavity for receiving an ampoule.

[0041] The use of two ampoules instead of one larger one makes it possible to keep the liquid volume in the ampoules below 30 ml, which takes advantage of the restrictions associated with larger quantities according to the Hazardous Substances Regulation.

[0042] In one embodiment, a common snap line is provided in both second cavities, so that both ampoules arranged in the second hollow body can be broken open from the outside by a single snap action. Single snap action means a single snap movement, which can in particular be performed by a single force applied from the outside. Thus, only one movement is required to open both ampoules.

[0043] In particular, both ampoules can be broken open simultaneously. Typically, the second cavities are arranged parallel to each other and have the same orientation. In this case, the snap line extends perpendicular to the longitudinal axis of the second cavities, in particular along the transition between the head region and the body region.

[0044] In one embodiment, the first hollow body comprises a first connecting element and / or the second hollow body comprises a second connecting element, in one embodiment, the first connecting element and the second connecting element are configured such that the first hollow body and the second hollow body are manually and releasably connectable to each other.

[0045] The first and second connecting elements are in particular directly connected to each other. The first and second connecting elements are typically designed as corresponding elements, for example as corresponding threads. The connection means a mechanical connection in which the two hollow bodies are fixedly connected to each other and thus can be moved together, for example.

[0046] In particular, the connecting element is designed in such a way that in the connected state, the longitudinal axis of the first hollow body and the longitudinal axis of the second hollow body are positioned one above the other, so that the liquid can flow into the powder via a short, straight flow path.

[0047] In one embodiment, the device further comprises an adaptor connectable to the first connecting element, the adaptor preferably configured to retain a mixture for producing a bone cement within the first hollow body.

[0048] In other words, with the adapter connected, the mixture is prevented from flowing out of the first hollow body. In this way, the contents of the first hollow body can be mixed when the adapter is connected. This facilitates mixing, since the device in which the adapter is placed on the first hollow body instead of the second hollow body is smaller and more manageable.

[0049] In particular, the adapter is configured to allow the gas to continue to leak out of the first hollow body, thus allowing a more effective kneading, so that the mixing is further improved. In particular, the adapter comprises a filter element which retains the mixture and / or allows the gas to pass through. The filter element can be designed in the same way as the filter element of the second hollow body.

[0050] In one embodiment, the device further comprises an ejection element having a third connecting element, in particular the ejection element being connectable to the first connecting element of the first hollow body.

[0051] The ejection element serves to eject the generated bone cement from the first hollow body. In particular, this can be achieved by pressing the first hollow bodies together. Instead of the second connecting element, the third connecting element is typically connected to the first connecting element after releasing the second connecting element from the first connecting element. By connection is meant a mechanical coupling such that there is a fluid connection between the first cavity and the interior of the ejection element. In particular, the ejection element can be manually connected to the first connecting element. In particular, a mechanical interlocking connection and / or a friction interlocking connection is meant. In this way, a particularly simple handling is made possible.

[0052] The ejection element preferably has a nozzle by which the bone cement can be accurately delivered to the target location. The nozzle is preferably arranged at an end of the ejection element opposite the third connecting element.

[0053] In one embodiment, the first hollow body is made from a material having a Shore A hardness of 30-80.

[0054] In one embodiment, the first hollow body is manufactured from a material having a Shore A hardness of more than 30, in particular more than 40, preferably more than 50 and / or less than 80, preferably less than 70, in particular less than 60. Such materials have proven to be particularly advantageous with regard to the required elasticity.

[0055] A further aspect of the invention is a method for producing bone cement, in particular using the device according to the invention. The method comprises kneading the elastic first hollow body from the outside, in particular by hand, in order to mix the contents of the first hollow body. In particular, the first hollow body encloses a first cavity for receiving a powder and has a first opening. In particular, a second hollow body is present. In particular, the second hollow body encloses a second cavity for receiving an ampoule and has a second opening. In particular, during kneading, the first opening and the second opening are fluidly connected to each other. In particular, the first hollow body is arranged such that the first opening faces upwards.

[0056] In one embodiment, the method comprises applying a force to the first hollow body from the outside. In this way, gas present in the first hollow body can flow out of the first hollow body through the first opening. In particular, the gas can enter the second hollow body through the second opening, flow through the ampoule present in the second cavity, and / or exit the second cavity through a third opening of the second hollow body. In one embodiment, the method comprises breaking the second hollow body from the outside, so that the ampoule breaks open and the liquid present in the ampoule is released. In one embodiment, the method comprises releasing the force applied to the first hollow body. In this way, a negative pressure can be generated by the restoring force of the wall of the first hollow body in order to suck the released liquid into the first hollow body. In particular, kneading follows afterwards. In one embodiment, the method comprises detaching the second hollow body from the first hollow body, connecting an ejection element to the first hollow body, and / or ejecting the bone cement generated by applying an external force to the first hollow body.

[0057] In one embodiment, the force for pushing the gas out of the first hollow body is applied before the ampoule is broken open. In an alternative embodiment, the ampoule is first broken open and then a force is applied from the outside to the first hollow body once or multiple times. In this way, the gas can flow out in one or more portions and a corresponding portion of the liquid can be sucked in by the resulting negative pressure.

[0058] Exemplary embodiments of the invention are also described in more detail below with reference to the drawings. The features of the exemplary embodiments can be combined individually or in the multiple claimed subject matter, unless otherwise stated. The scope of the claimed protection is not limited to the exemplary embodiments. [Brief description of the drawings]

[0059] [Figure 1] FIG. 1 is a perspective view of a device according to the invention. [Diagram 2]FIG. 2 is a cross-sectional view of a device according to the invention. [Diagram 3] FIG. 3 is a further cross-sectional view of a device according to the invention. [Figure 4] FIG. 4 is a further cross-sectional view of a device according to the invention. [Diagram 5] FIG. 5 is a further cross-sectional view of a device according to the invention. [Figure 6] FIG. 6 is a further cross-sectional view of a device according to the invention. [Figure 7] FIG. 7 is a cross-sectional perspective view of a device according to the present invention. [Figure 8] FIG. 8 is a perspective view of a device according to the invention. [Figure 9] FIG. 9 is a perspective view of a device according to the present invention. [Figure 10] FIG. 10 is a detailed cross-sectional view of a device according to the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0060] FIG. 1 shows a device 10 for mixing bone cement. The device 10 comprises a first hollow body 11, a second hollow body 21 and an optional discharge element 58. In particular, each of the hollow bodies 11, 21 is made from rubber and / or plastic. The first hollow body 11 comprises a first opening 15. A first connecting element 61 in the form of an external thread is arranged in the region of the first opening 15. The second hollow body 21 comprises a second opening 25 and a third opening 28. The third opening 28 is closed by a gas-permeable cap 29. The cap 21 can be designed to be removable in order to allow an ampoule to be inserted into the second hollow body 21. The two openings 25, 28 are arranged in particular in the middle of both ends of the second hollow body 21.

[0061] A second connecting element 62 in the form of an internal thread is arranged in the region of the second opening 25. The first hollow body 11 and the second hollow body 21 can be mechanically connected to one another by means of the connecting elements 61, 62. In the connected state of the two hollow bodies 11, 21, the first opening 15 and the second opening 25 are fluidly connected to one another.

[0062] The ejection element 58 comprises a nozzle 59 for ejecting the bone cement and a third connecting element 63, in particular in the form of an internal thread which corresponds to the internal thread of the second connecting element 62. In this way, the ejection element 58 can be mechanically connected to the first connecting element 61 of the first hollow body 11 instead of the second hollow body 21.

[0063] Figure 2 shows in cross section a device 10 which may correspond to the device of figure 1. As mentioned above, the first hollow body 11 and the second hollow body 21 are mechanically connected to each other by connecting elements 61, 62. The first hollow body 11 encloses a first cavity 12 which is partly filled with powder 14 and partly filled with a gas 30, for example air. The second hollow body 21 encloses a second cavity 22 in which an ampoule 24 is present. The ampoule 24 is partly filled with liquid 32, partly filled with gas 30 or completely filled with liquid 32.

[0064] The ampoule 24 consists of an essentially cylindrical body 42 and an adjacent head 46. In FIG. 2, the head 46 faces downwards. At the transition between the body 42 and the head 46 there is a predetermined breaking point for separating the head 46 from the body and thus releasing the liquid 32. The second cavity 22 of the second hollow body 21 is therefore divided into a substantially cylindrical body region 40 for accommodating the body 42 and a head region 44 adjacent to the body region 40 for accommodating the head 46. The second hollow body 21 is elastic at least in the region of the predetermined breaking point, so that the ampoule 24 can be opened as described by snapping from the outside along the snap line 54.

[0065] A second fluid connection 52 in the form of a straight flow duct is arranged between the lower end of the head region 44 opposite the body region 40 and the second opening 25. At the lower end of the flow duct in the region of the second opening 25 there is a filter element 38 which is able to filter the flow passing through the second opening 25. In this way, for example glass shards generated when the ampoule 24 is opened can be retained as the liquid 32 flows through the second opening 25.

[0066] Figures 3 to 5 show the successive steps of a method for producing powdered cement. The device 10 used for this purpose corresponds in particular to the device of figure 2. In figures 3 and 5, the device 10 is shown rotated by 90° along its longitudinal axis. Here, it is shown that in addition to the second fluid connection 52, two first fluid connections 51 are also present between the second cavity 22 and the second opening 25. Two, for example curved, flow ducts extend between the lower end of the body region 40 facing the head region 44 and the straight flow duct of the second fluid connection 52. The first fluid connections 51 are thus arranged above the predetermined break point or at least at the same height as the predetermined break point. In this way, the liquid 32 can flow through the second opening 25 even if the head region 44 is clogged by a broken head 46 of the ampoule 24 or by glass fragments.

[0067] 3 shows the state in which a manual force is applied to the first hollow body 11 from the outside. The first hollow body 11 is pressed together. The gas present above the powder 14 thus flows through the second opening 25 and the fluid connections 51, 52 into the second cavity 22, passes through the ampoule 24 and leaves the second hollow body 21 through the third opening 28. The filter element 38 can prevent the powder 14 from entering the second hollow body 21.

[0068] FIG. 4 shows the snapping action of the second hollow body 21 along the snap line 54 by applying a manual force from the outside. As a result, the head 46 of the ampoule 24 is separated from the body 42 and the liquid 32 is released. The liquid 32 starts to flow downwards. Now the manual force applied to the first hollow body 11 is removed. Due to the restoring force exerted by the walls of the first hollow body 11, a negative pressure is created in the first hollow body 11, which, in addition to the action of gravity, sucks the liquid 32 downwards. FIG. 5 shows the situation after most of the liquid 32 has already flowed into the first hollow body 11. As soon as the first hollow body 11 has returned to its original shape again and / or the required amount of liquid 32 has flowed into the first hollow body 11, the elastic first hollow body 11 can be kneaded from the outside in this way so that the powder 14 is mixed as homogeneously as possible with the liquid 32. Now the filter element 38 prevents the mixture from flowing into the second hollow body 21. In this manner, a processed bone cement is produced in the first cavity 12 .

[0069] 6 shows the distribution of the produced bone cement. Here, instead of the second hollow body, an ejection element 58 is fixed to the first connecting element 61 of the first hollow body 11. By applying manual pressure from the outside to the flexible first hollow body 11, the produced bone cement 34 is forced out through a nozzle 59.

[0070] Figures 7 and 8 show another embodiment of the device 10 according to the invention. Different from the previously described device, the second hollow body 21 now surrounds two second cavities 22. An ampoule 24 is present in each second cavity 22. Each of the second cavities 22 is connected to a second opening 25 by one or more fluid connections. Figure 8 shows that the two second cavities 22 are provided with a common snap line 54. The liquid from the two ampoules 24 can therefore be released from the outside by one snapping movement.

[0071] Figures 9 and 10 show another embodiment of the device 10 according to the invention. In addition to what has already been described, the device 10 shown here comprises an adapter 56. It comprises a fourth connecting element 64 in the form of an internal thread that essentially corresponds to the second connecting element 62. The adapter 56 further comprises a fifth connecting element 65 in the form of an external thread that essentially corresponds to the first connecting element 61. The adapter 56 can thus be screwed onto the first connecting element 61 and the second connecting element 62 and can thus be arranged between the first hollow body 11 and the second hollow body 21, as shown in Figure 10. Liquid from the ampoule can thus flow through the adapter 56 into the first cavity 12.

[0072] The adapter 56 further comprises a second filter element 39, which is in particular designed similarly to the first filter element 38. The second filter element 39 is in particular located at the end of a flow duct extending through the adapter 56, which end faces the first hollow body 11 during the intended use. In this way, the second filter element 39 prevents the mixture for producing the bone cement from leaving the first hollow body 11 when the first hollow body 11 is being kneaded. It is therefore possible to carry out kneading from the outside to mix the bone cement while the second hollow body 21 is separated from the first hollow body 11 and only the adapter 56 is placed on the first hollow body 11. In this way, the device becomes more manageable and facilitates mixing. Overall, the first hollow body 11 and the second hollow body can therefore be connected directly or indirectly by an intervening adapter. [Explanation of symbols]

[0073] 10 Devices 11 First hollow body 12 First Cavity 14 powder 15 First opening 21 Second hollow body 22 Second Cavity 24 Ampoule 25 Second Opening 28 Third Opening 29 Cap 30 Gas 32 liquid 34 Bone cement 38 Filter Elements 39 Second Filter Element 40 Body area 42 Main Body 44 Head Area 46 Head 51 first fluid connection 52 second fluid connection 54 Snap Lines 56 Adapter 58 Emission elements 59 Nozzle 61 First connecting element 62 Second connecting element 63 Third Connection Element 64 Fourth Connection Element 65 The fifth connecting element

Claims

1. 1. A device (10) for mixing a bone cement (34), comprising a first hollow body (11) surrounding a first cavity (12) for receiving a powder (14) and having a first opening (15) and a second hollow body (21) surrounding a second cavity (22) for receiving an ampoule (24) and having a second opening (25), the first hollow body (11) and the second hollow body (21) being connectable to each other such that the first opening (15) and the second opening (25) are fluidly connected to each other, the first hollow body (11) being elastic such that the contents of the first hollow body (11) can be mixed by kneading, compressing and releasing the first hollow body (11) by application and cessation of an external force.

2. The device (10) according to claim 1, characterized in that the second hollow body (21) further comprises a third opening (28) through which gas (30) in the first hollow body (11) can flow out of the second hollow body (21) in response to compression of the first hollow body (11).

3. 3. The device (10) according to claim 1 or 2, characterized in that the second hollow body (21) is at least partially elastic so that it can be bent from the outside in order to break and open an ampoule (24) present in the second cavity (22).

4. 3. The device (10) according to claim 1 or 2, characterized in that the second hollow body (21) has a filter element (38) arranged such that the flow passing through the second opening (25) is filtered.

5. The device (10) according to claim 1 or 2, characterized in that the device (10) comprises an ampoule (24) received in the second cavity (22).

6. The device (10) of claim 1 or 2, characterized in that the device (10) includes a powder (14) received in the first cavity (12).

7. 7. The device (10) of claim 6, wherein the first cavity (12) has a volume that corresponds at least to the sum of the volume of the powder (14) and the volume of the liquid (32) receivable in the ampoule (24).

8. 3. The device (10) according to claim 1 or 2, characterized in that the second cavity (22) has a body region (40) for receiving the body (42) of the ampoule (24) and a head region (44) for receiving the head (46) of the ampoule (24), and at least one first fluid connection (51) is formed to bypass the head region (44) and communicate an end of the body region (40) facing the head region (44) with the second opening (25).

9. 9. The device (10) according to claim 8, characterized in that a second fluid connection (52) is present between the end of the head region (44) facing away from the body region (40) and the second opening (25).

10. 3. The device (10) according to claim 1 or 2, characterized in that the second hollow body (21) encloses two second cavities (22), each second cavity (22) being configured to receive an ampoule (24).

11. 11. The device (10) according to claim 10, characterized in that a common snap line (54) is provided for the two second cavities (22) so that the two ampoules (24) present in the second hollow body (21) can be broken open from the outside by a single snap action.

12. 3. The device (10) according to claim 1 or 2, characterized in that the first hollow body (11) has a first connecting element (61) and the second hollow body (21) has a second connecting element (62), the first connecting element (61) and the second connecting element (62) being configured such that the first hollow body (11) and the second hollow body (21) are manually and removably connectable to each other.

13. The device (10) according to claim 12, characterized in that the device (10) further comprises an adapter (56) connectable to the first connecting element (61) and configured to retain a mixture for producing a bone cement (34) in the first hollow body (11).

14. The device (10) according to claim 12, characterized in that it further comprises an ejection element (58) having a third connecting element (63) which can be connected to the first connecting element (61) of the first hollow body (11).

15. The device (10) according to claim 14, characterized in that the first hollow body (11) is made of a material having a hardness of 30-80 Shore A.

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