US20070034646A1

US20070034646A1 - Foil monomer container and dispenser

Info

Publication number: US20070034646A1
Application number: US11/202,785
Authority: US
Inventors: Paul Higham; Robert Klein
Original assignee: Howmedica Osteonics Corp
Current assignee: Howmedica Osteonics Corp
Priority date: 2005-08-12
Filing date: 2005-08-12
Publication date: 2007-02-15

Abstract

A metallic container for storing the liquid monomer component of bone cement and a method of packaging same are disclosed. The container is preferably aluminum and has an interior wall, a dispensing end, a reservoir for housing the liquid monomer, and a filling end for receiving the liquid monomer. The container is sealed by a welded seam near the filling end of the container, which secures a section of the top portion and lower portion of the interior wall of the container together.

Description

BACKGROUND OF THE INVENTION

The present invention relates to containers for housing liquid monomers used in two-part bone cement systems, and more particularly to welded metallic containers for housing liquid monomer and methods of making same.
Bone cement is well known in the surgical community for its ability to improve the strength, rigidity, and movement of the bone/joint structure. It is used during surgical procedures, such as the attachment of a prosthesis or pathological fracture fixation. With regard to the attachment of a prosthesis, the cement is packed into the bone and the prosthesis is then implanted. The cement cures and a bond develops between the bone and the prosthesis. Other uses of bone cement include repairing or mending bone fractures or shattered bone occurring from extreme trauma. Bone cement may also be used as a drug delivery or release system, whereby the bone cement is mixed with antibiotics or other desired drugs and applied to a specific surgical site such that the drugs leach out and are delivered directly to the surgical site. Some bone cements are even designed to be absorbed by the body over time.
Acrylic type Bone cement is comprised from the combination of a polymeric powder component and a liquid monomer. The liquid monomer is typically a methyl methacrylate monomer, and the polymeric component is typically a methyl polymethylmethacrylate. An example of such a bone cement is sold under the trademark Simplex® P by the assignee of the present invention. Because the liquid monomer component polymerizes the powder component, the two components must be thoroughly blended together in order to achieve the required consistency. Due to the volatility resulting from the combination of the liquid monomer and polymeric powder, however, the two components must be separated until just prior to the need for the bone cement during a surgical procedure. Thus, separate packaging for the liquid monomer and polymeric component is desired to avoid any premature reactions.
Glass ampoules are commonly used to store the liquid monomer. Glass is one of the most effective materials for storing liquid monomers. The glass is inert, and has no chemical activity with the monomer. Moreover, the glass acts as a hermetic seal, preventing both the loss of the liquid monomer and environmental contamination of the liquid monomer. Indeed, achieving a hermetic seal is a function of both the bulk permeability of the chosen materials and the seal quality.
There are several drawbacks, however, arising from the use of glass ampoules to store liquid monomer. In the operating room, the glass ampoule must be fractured to release the liquid monomer. The resulting fractured glass shards pose hazards to both the patient and the operating room staff. Furthermore, prior to the transfer of the glass ampoules to the operating room or intended destination, the fragile glass ampoules are susceptible to unintentional and premature fractures.
Storing the liquid monomer in a flexible container is one proposed and alternative solution for dealing with the problems presented by using glass ampoules. Specifically, flexible containers comprised of aluminum are a favored alternative to the glass ampoule because pure aluminum does not react with the monomers. Like glass, however, known aluminum flexible containers for housing liquid monomer also have drawbacks.
Known containers for housing liquid monomers are not capable of being comprised of pure aluminum. This is due to the fact that no methods previously existed for creating a container for liquid by providing a metal-to-metal weld which provided a hermetic seal. Rather, the prior art methods require that metallic prior art containers must be coated (at least on one side) with a material that aids in sealing the container. For example, polyethylene is a material commonly coated onto aluminum or the like to help facilitate the sealing or welding process. The use of such a coating, however, limits the long-term ability of the container to effectively prevent the leakage of liquid monomer. The materials used to coat the aluminum, such as polyethylene, are attacked by the methacrylate monomer, which acts as a powerful organic solvent. The methacrylate monomer causes the breakdown of such materials, which, in turn reduces the effectiveness of the seal and results in the leakage of liquid monomer. Crimping is an example of one such prior art method of sealing a container that relies on a coating of polyethylene to achieve a hermetic seal.

SUMMARY OF THE INVENTION

The present invention is designed to overcome or minimize the shortcomings of prior art containers by providing a containment barrier, preferably a welded seam, which results in a more leak-resistant and cost-effective flexible container for housing liquid monomer. Such containers, preferably made of pure aluminum, are easy and safe to use during operating conditions, capable of preventing the escape of liquid monomer, provide a containment barrier or welded seam on the order of 1×10⁻⁸atm-cc/s Helium, and are cost-effective to manufacture and fill. This represents a substantial improvement to the containment barrier provided by mechanical crimping, which is less than 1×10⁻⁴atm-cc/s Helium. The containment barrier is preferably a welded seam that is preferably a metal-to-metal seam or one wherein the interior walls of the container are welded together without an intermediate material or coating between them. Various containers in accordance with the present invention are therefore disclosed which provide improvements over prior art containers.
In accordance with one aspect of the present invention, a container for storing a liquid monomer of a two-part bone cement system is provided. The container further includes a dispensing end, a reservoir having a surface for contacting the liquid monomer, a filling end for receiving the liquid monomer, and a welded seam on the filling end for securing the container closed, wherein the welded seam that is preferably a metal-to-metal weld. Preferably, the container is uncoated and made from aluminum. Furthermore, it is preferable that there are two seams which overlap one another. In an alternative embodiment the container may be a flexible pouch having a plurality of sides. The pouch is preferably in the shape of a rectangle, but it can take on alternative shapes, such as a square or triangle. In another feature of this aspect of the present invention, the container is constructed and arranged to fit into an inlet of a bone cement mixer. Preferably, the outlet of the container is threaded, and the inlet of the bone cement mixer has complementary threading so that said container is capable of being connected to the bone cement mixer. In another feature of the present invention, the welded seam is preferably an ultrasonically welded seam. Alternatively, the welded seam may be a laser welded seam or an electron beam welded seam.
In accordance with another aspect of the present invention, there is a container for storing a liquid monomer. The container has an interior wall, a dispensing end, a reservoir having a surface that contacts the liquid monomer, a filling end for receiving the monomer, and at least one welded seam for securing the interior wall of the container together to form a sealed filling end. At least a portion of the interior wall is non-reactive with the liquid monomer, and the welded seam is located at a location wherein the portion of the interior wall that is non-reactive with the liquid monomer is located.
In yet another aspect in accordance with the present invention, there is a method for packaging a liquid monomer of a two-part bone cement system that includes forming an aluminum sheet having an uncoated surface for contacting the liquid monomer into a container having an open end and a closed end, filling the container with liquid monomer through the open end, and providing a welded seam on the open end of the container to seal the container with the liquid monomer.
These and other features and characteristics of the present invention will be apparent from the following detailed description of preferred embodiments which should be read in light of the accompanying drawings in which corresponding reference numerals are provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a sealed container for housing a liquid monomer in accordance with the present invention including a welded end portion A-A;
FIG. 2 is a perspective view of the pre-sealed outlet end of the container shown in FIG. 1;
FIG. 3 is a perspective view of the container shown in FIG. 1, prior to being filled with liquid monomer and welded;
FIG. 4A is an enlarged elevational view of the preferred end portion A-A shown in FIG. 1 after welding;
FIG. 4B is an enlarged elevational view of an alternate embodiment of portion A shown in FIG. 1 after welding;
FIG. 5 is an elevational view of the end of a filled container in accordance with the present invention sealed by an alternate weld pattern;
FIGS. 6A-6D illustrate the steps of assembling a pouch-type container in accordance with the present invention;
FIG. 7 is an alternative pouch-type container in accordance with the present invention;
FIGS. 8A-8D illustrate the steps of assembling another alternative pouch-type container in accordance with the present invention;
FIG. 9 is a cross sectional view of a typical bone cement mixer adapted to connect to a container in accordance with the present invention;
FIG. 10 is a top view of the inlet of the bone cement mixer shown in FIG. 9; and
FIG. 11 is a cross-sectional view of the inlet of the bone cement mixer shown in FIG. 9 along lines 11-11.

DESCRIPTION OF THE DRAWINGS

Referring to FIG. 1, there is illustrated a preferred container 100 that houses a liquid monomer for use in a two-part bone cement system. The container 100 is preferably comprised of a thin-walled commercially pure aluminum sheet (approximately 0.005″ thick) that has been extruded into a seamless cylindrical tube in a well known manner. The filled container 100 has a first end 102 for loading the liquid monomer that has been preferably sealed by an ultrasonically welded seam 104 and an opposed end 106 that has a pre-sealed threaded outlet 108 having a threaded outer surface 116 (See FIG. 2). A threaded cap 109 may also be used to cover the outlet 108.
Prior to being filled with liquid monomer and sealed, container 100 appears (in its original state) as the open tubular container 100′ shown in FIG. 3. The container 100′ is preferably an empty tube with a sealed and preformed outlet end such as shown in FIG. 2. Furthermore, the interior surface or wall 103 of the open container 100′ is preferably uncoated so that the container 100′ is non-reactive with the liquid monomer (i.e., the liquid monomer will not attack the interior walls of the container). Such preformed containers 100′ are commercially available from Montebello Packaging of Oak Park, Ill. It should be appreciated, however, that coating the interior surface with a material that is non-reactive with liquid monomer is an acceptable alternative.
In a preferred embodiment, the container 100′ has a ⅞ of an inch diameter and a wall thickness of 0.005±0.0005 inches. The container 100′ has an open filling end 102′, an opposed end 106′ and a threaded cap 109′ that fits over a pre-sealed applicator or outlet 108, such as the end shown in FIG. 2, at the opposed end 106′ of the container 100′. The container 100′ may be filled with liquid monomer through open end 102′ using any known method of aseptic filling after being placed in the upright position. The container 100′ can be sterilized as part of the aseptic process or presterilized and transferred into the sterile environment. An automated filling process through a needle can be used to insure filling of the container 100′ in its open state without wetting of the upper inner surface adjacent end 102′, but any known method may be used to fill the container 100′.
Once container 100′ is filled, open end 102′ is preferably flattened, so that a portion of the outer half 117 and inner half 119 of the interior wall 103 adjacent end 102′ are joined together to close the open end 102′, and the container 100′ remains in an upright position without spilling the contents while it is transferred to the machine which will seal the container 100′. The now closed end 102′ is then sealed by a welding process. As will be described in greater detail below, it is preferred that an ultrasonic welder be used to provide an ultrasonically welded seal using parameters that will be disclosed more fully herein. The result is a metal-to-metal weld which results in hermetic sealing of the container. That is, because there are preferably no intermediate materials or coatings between the outer half 117 and inner half 119 of the interior wall 103 during the welding process, it is possible to create a seal prevents any non-acceptable loss of liquid monomer and prevents contamination of the liquid monomer. At the conclusion of the filling and welding process, container 100′ appears as container 100 shown in FIG. 1.
When it is desired to dispense the liquid, the liquid monomer can be dispersed through threaded outlet 108 of opposed end 106 of container 100 for example when the seal 111 (See FIG. 2) of outlet 108 is punctured by the pointed tip 115 of the threaded cap 109. It should be appreciated, however, that any known method of puncturing the seal 111 of the outlet 108 may be utilized.
Use of low temperature ultrasonic welding to seal the container is one aspect of the present invention. Ultrasonic welding is the process for joining metals, such as aluminum, using high-frequency vibratory energy that is converted to high-frequency mechanical energy in the form of reciprocating vertical motion. The basic process involves vibrating one item (commonly referred to as the “horn”) at ultrasonic frequencies relative to a second stationary item (commonly referred to as the “anvil”). The item to be welded (commonly referred to as a “weldment”) is clamped between the horn and the anvil, thereby allowing the horn to transfer the ultrasonic vibrations to the weldment. The ultrasonic vibrations, in combination with the clamping, provide the forces required to make the ultrasonic metal weld. As will be discussed in further detail herein, ultrasonic welding in accordance with the present invention provides reduced leak rate levels on the order of 1×10⁻⁸atm-cc/s, of Helium, i.e., a rate that approaches hermetic sealing and a rate over four orders of magnitude of improvement to mechanical crimping. This is due, in part, to the fact that ultrasonic welding permits sealing of the container without excessive melting and thinning of the container wall. Accordingly, a container in accordance with the present invention is a vast improvement over the prior art. Indeed, the leak rate is in excess of ten thousand times lower than the leak rates available through use of mechanical crimping.
Creating a welded seam on the container that is capable of providing a seal with minimal leak rates while still providing enough strength to keep the container shut is dependent upon various weld parameters. For example, power level, weld time and weld pressure are variable parameters that can be adjusted to obtain the optimum weld and reduced leakage rates. The welding is preferably performed at room temperature; no preheating of the metallic container is required. Power level is the intensity of the vibration that the ultrasonic welding machine is transmitting through the weldment. The weld time is the amount of time that the horn is vibrating and in contact with the weldment (i.e., the container walls). An increase in weld time will increase the strength of the weld. However, after a certain period of time, the vibrations can cause damage to the neighboring tube wall, resulting in a low seal strength due to rupture of the tube wall. Finally, the weld pressure is the force the welding device must use to push the parts together. A force that is too small is unable to provide good vibration transmission, resulting in an incomplete weld. In contrast, too much force will eventually cause the seal to fail as a result of the texture on the tool faces perforating the tube wall or damaging the neighboring tube wall. Accordingly, all of these factors must be taken into consideration when it is desired to obtain a container having a strong weld capable of keeping the container secured shut and providing a low leakage rate.
Several tests were conducted to determine what parameters should be used to achieve optimum results. The following examples provide parameters that can achieve an ultrasonically sealed container whose weld retains a high degree of strength, while maintaining leakage rates on the order of 10⁻⁸atm-cc/s of Helium.

EXAMPLE 1

In a preferred embodiment, a Sonobond® Welder model 1600 manufactured by Sonobond Ultrasonics Inc. of West Chester, Pa., a commercially available ultrasonic welder, may be used to provide a welded seam 104 at the first end 102′ of the container 100′ shown in FIG. 3. The ultrasonically welded seam 104 preferably occurs as a straight band or line extending across the length of the first end 102 of the container 100. The best results for achieving optimum leak rates and weld strength for a tube ⅞″ in diameter with a wall thickness of 0.005″±0.0005 are obtained using the following parameters: Weld Pressure=40 psi, Power Level=900 W, and Weld Time=0.1 seconds.
Referring to FIG. 4A, in a preferred embodiment, the distance A of welded seam 104 away from the first end 102 of container 100 is preferably 0.375 inches. Furthermore, the Sonobond® Welder horn used with the Sonobond® welder creates a welded seam 104 on the ⅞″ diameter tube wherein the length B of the welded seam 104 is preferably about 1.4 inches (a length, preferably slightly larger than the base of the container due to deformation) and the thickness C of the welded seam 104 is approximately 0.1 inches. Thus, the total weld area of the welded seam 104 is approximately 0.14 in².
Referring to FIG. 4A, it is preferred that the welded seam 104 is comprised of at least two overlapping welds in order to insure a tight seal for the container. This is because the edges of the flattened tube (where the aluminium is folded over on itself) was the most difficult area to weld. Since the ultrasonic energy is more concentrated in the center of the horn, two overlapping welds allow each edge to be placed adjacent the center of the horn. The thickness of the Sonobond® welding tools are sufficient to span the thickness C of the container 100′ and welded seam 104, however the length of the Sonobond® tools does not span the entire length B of the desired thickness C of the welded seam 104. Accordingly, two overlapping welds are needed to increase the overall length of the welded seam 104. Furthermore, as stated above, overlapping also allows the first end 102 of the container 100 to be placed toward the center of the horn, where ultrasonic energy is concentrated.
Referring to FIG. 4A, a first weld 105, defined by a distance E, is created near the first side 200 of the container 100′. (The distance B or length of the weld remains approximately 1.4 inches.) The distance G or length of the first weld 105 is approximately 1 ⅛ of an inch. A second weld 107 on side 202 is then created such that the distance H is also approximately 1 ⅛ of an inch in length and overlaps the first weld 105 by a distance I of approximately 0.75 of an inch. The second weld 107 is preferably aligned with the first weld 105.
In addition to the lengthwise overlap of the welds the welds may overlap to produce a wider or thicker weld. The weld can be shifted either toward or away from end 102 of the tube to produce a wider weld F or D. The width of F or D can be about ⅛ to ¼ inches with the overlap E being about 1/16 to ⅛ inch.
The horn utilized in connection with the Sonobond® welder preferably has a knurled counterface and the anvil has a smooth counterface. The horn and anvil preferably have an appropriate length and shape to ensure vibrational harmony with the ultrasonic energy source.

EXAMPLE 2

In an alternative embodiment, an AmTech® Ultraweld 20 manufactured by AmTech®, of Danbury, Conn., another commercially available ultrasonic welder, may be used to weld the edge of a container similar to the one shown in FIG. 1. The Amtech® welder has similar parameter settings as the Sonobond® welder, but uses different names for two of the parameter settings. Specifically, the amplitude setting on the Amtech® is analogous to the power setting on the Sonobond® and regulates the intensity of vibration transmitted through the weldment. The energy setting on the Amtech® welder is similar to the time setting on the Sonobond®,where higher energy settings result in longer weld times. Good results were obtained for preventing leakage using the Amtech® welder using the following parameters: Pressure=80 psi, Amplitude=30 um, and Energy=150 Joules. The tool interface used in the Amtech® welder is wider than the tool interface of the Sonobond® welder. As shown in FIG. 4B, this results in a larger welded seam 104′. The length B′ of the welded seam 104′ again is about 1.40 inches, but the width C′ of the weld is 0.2 inches, which provides a total weld area of 0.28 in²(i.e., two times the size of the welded seam 104 created by the Sonobond® welder of Example 1.)
As discussed with regard to FIG. 4A, it is also preferred that at least two welds overlapping lengthwise be used. Referring to FIG. 4B, if an overlap in width, i.e. along the length of the tube, is also used, the first alternate weld 105′ is defined by the distance G′, which is approximately ¼ to ⅜ inches. A second alternate weld 107′, is defined by the distance H′, which is also approximately ¼ to ⅜ inches, and overlaps the first alternate weld 105′ by a distance I′ of about ⅛ inch. The lengthwise overlaps are the same as those used with the Sonobond® welder shown in FIG. 4A. The Amtech® welder also preferably utilizes a horn with a knurled counterface and an anvil with a smooth counterface. Furthermore, like the tools of the Sonobond® welder, the horn and anvil of the Amtech® welder have an appropriate length and shape to ensure vibrational harmony with the ultrasonic energy source.
It should be appreciated that while it is preferred to create a welded seam through the use of ultrasonic welding, the metallic container can be sealed by other means of metallic fusion joining, provided that the final seal is made at an adequate distance away from the liquid monomer, such as at least 1.5 inches away from the monomer. Methods of fusion joining that require lower amounts of thermal energy by using a narrow weld zone, such as laser welding or electron beam welding, or other methods that do not melt the container walls, such as friction pulse bonding or brazing are alternative economical methods that may be utilized in accordance with the present invention. Indeed, the distance required to keep the container walls in contact with the liquid monomer below its igniting point of 815° F. is consistent with the head space required to keep the methyl methacrylate from spilling during the sealing operation.
It should also be appreciated that different weld patterns may be utilized in accordance with the present invention to obtain an alternative container for housing liquid monomer. For example, referring to FIG. 5, an alternate container 114 utilizing an alternate ultrasonically welded seam pattern is comprised of two weld lines 110, 112 that overlap each other at one end. The weld lines 110, 112 are diagonal and extend from the outermost edge 118 of the walls of the alternate container 114 and meet to form a point along the bottom edge 113 of the alternate container 114. The same welding parameters discussed in Examples 1 and 2 above may be used to achieve the diagonal weld lines 110, 112.
Referring to FIG. 6D, another alternative embodiment for a container capable of housing liquid monomer is shown. Specifically, a flexible container or pouch 120 having a plurality of sides is shown. The pouch is preferably comprised of aluminum that has no coating and is preferably ultrasonically welded along three of its four sides. The welding may be conducted in accordance with the parameters described above. Of course, the horn and anvil dimensions would be changed to accommodate the desired weld lengths.
Referring to FIGS. 6A-6D, a method of making the flexible pouch 120 shown in FIG. 6D is illustrated. FIG. 6A illustrates a sheet 121 of aluminum. In a preferred embodiment, the sheet 121 is approximately 4 inches×6 inches×0.005 inches in size. Referring to FIG. 6B, the sheet 121 is folded in half and has first, second, third, and fourth sides 122, 124, 126, 128, wherein the second and fourth sides 124, 128 are preferably shorter than the first and third sides, 122, 126. Referring to FIGS. 6C and 6D, after folding the sheet 121 in half, the second and fourth sides 124, 128 are ultrasonically welded so as to create two welded seams 130, 132 that run the entire vertical length of the second and fourth sides 124, 128. The welding parameters previously described herein may be utilized to form the welded seams 130, 132. When the two welded seams 130, 132 are completed, a pocket or opening 134 is also formed between the welded seams 130, 132. The pocket 134 of the pouch 120 is then filled with the appropriate amount of liquid monomer. Thereafter, as shown in FIG. 6D, a welded seam 133 can be used to completely seal the flexible pouch 120.
A means for opening the flexible pouch, such as a slit or notch 136, may be placed onto an area outside of the welded seams 130, 132. The notch 136 may be cut using conventional methods of notching, such as punching the shape of a notch directly onto the walls of pouch 120. The shape of the notch 136 may take on any desirable form such as a triangle or square. It should be appreciated that any known methods of providing an opening for the pouch 120 may be utilized in accordance with the present invention.
When it is desired to open pouch 120, one may tear an opening into pouch 120 using the slit or notch 136. In order to successfully remove all of the contents of the pouch, a hypodermic needle (not shown) may be inserted through the pouch wall and into the liquid monomer. Similarly, vacuum pumping may also be utilized to withdraw the liquid monomer from the pouch. Inlets may be provided on the flexible pouch to provide an entrance for the needle to enter the pouch, without rupturing or puncturing other portions of the bag. A septum (not shown) can also be placed on the outer portion of the pouch to guide the needle thus preventing a puncture in other areas of the pouch.
Referring to FIG. 7, another alternate embodiment of a metallic container is shown. Here, four welded seams 170, 172, 174, and 176 are used to create an alternative container or dual pocket pouch 169 having a first compartment 178 and a second compartment 180. The creation of two compartments enables the two components of bone cement (i.e., liquid monomer and polymeric powder) to be housed in the same container. For example, the first compartment 178 may be used to contain the liquid monomer, and the second compartment 180 may be used to contain the polymeric powder component or vice versa. The center or second seam 172 prevents the liquid monomer from reacting with the polymeric powder. The steps necessary to create the package are similar to that disclosed in FIGS. 6A-6E. The only difference is that prior to creation the fourth welded seam 176, which is used to seal the package closed, first, second and third welded seams 170, 172, and 174, are created to provide a first compartment 178 and a second compartment 180. The package is then filled with liquid monomer and polymeric powder and then the fourth welded seam 176 is created, which overlaps the first, second and third welded seams 170, 172 and 174. Notches 182,184 may also be provided to provide access to the first and second compartments 178, 180.
Referring to FIGS.8A-8D, an alternate embodiment of a container 150 in accordance with the present invention is shown. The container 150 is triangular and has first, second and third sides 152, 154, and 156. Referring to FIG. 8A, the container 150 is formed from a sheet 158 preferably comprised of aluminum. As shown in FIG. 8B, the sheet 158 is folded in half, such that the third side 156 of the container 150 is the fold line of the folded sheet and the first and second sides 152,154 remain open. Referring to FIG. 8C, a first welded seam 160 is placed along the length of the first side 152 preferably using parameters described herein. The container is then filled with liquid monomer through the second side 154 of the container 150, which remains open. Thereafter, as shown in FIG. 8D, a second welded seam 162 is placed along the length of the second side 154 and overlaps a portion of the first welded seam 160. A notch 164 is also preferably located on the first side 152 of the container 150 so as to enable one to easily open the container 150.
The containers disclosed herein may be constructed and arranged so that they are capable of directly connecting to bone cement mixers. Bone cement mixers are devices used to combine the liquid monomer and polymeric powder components of the bone cement. For example, FIG. 9 illustrates a bone cement mixer 140 that may be used in connection with the containers for liquid monomers disclosed herein. In a preferred embodiment, bone cement mixer 140 has an inlet 142 that is capable of receiving the container 100 (or the alternative embodiments described herein). Referring to FIGS. 10-11, the inlet 142 preferably has a circular wall that preferably surrounds a means for puncturing the seal 111 of the outlet 108 of the container 100. The means preferably comprises a puncturing barb or stem 146 that is capable of puncturing the seal 111 of the outlet end 108, but any conventional means of puncturing known in the art may be utilized in accordance with the present invention. The design of barb 146 may be similar to that of tip 115.
As best shown in FIG. 11, the inlet 142 preferably has an outer mating sleeve 192 and an inner sleeve 190. The inner sleeve 190 is circular and preferably has a threaded portion 191 that complements threading found on the outlet 108 of the opposed end 106 of the container 100 (See FIGS. 1-2). This allows the container 100 to be securely screwed into the inlet 142.
The inlet 142 preferably has a mechanism for puncturing the container 100 which includes the inner sleeve 190 that engages the threaded outer surface 116 of the container 100, and which is captured on the outside by the outer mating sleeve 192 that allows translation of the fully engaged tube in a linear direction towards the puncturing stem 146 to fully pierce the seal 111 and retract via a spring mechanism 194 to allow transfer of the monomer. When container 100 is inserted into inlet 142, the seal 111 is then punctured by puncturing barb 146 of the inlet 142. The puncturing barb 146 is hollow and has an opening to allow transfer of the monomer into the bone cement mixer. A vacuum source or pump (not shown) attached or capable of being attached to the bone cement mixer 140 may then be used to withdraw all of the liquid monomer from container 100. The vacuum is typically used to vent fumes and reduce air entrapment during mixing.
Alternatively, containers such as pouches 120, 150 or as dual pocket pouch 169 may be used in connection with bone cement mixer 140. Pouch 120 may be opened and then simply poured into the mixer by removing the lid of the bone cement mixer 140. Alternatively, the inlet 142 may be fitted with an adapter (not shown) which fits over or into inlet 142 so as to be compatible with containers having different sizes or types of applicator ends to fit over the inlet.
Although the invention herein has been described with reference to particular embodiments and preferred dimensions or ranges of measurements, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. Additionally, it is to be appreciated that the present invention may take on various alternative orientations. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims.

Claims

1. A container for storing a liquid monomer of a two-part polymeric bone cement system comprising:

a dispensing end;

a reservoir having a surface for contacting said liquid monomer, said reservoir connected to said dispensing end;

a filling end for receiving said liquid monomer, said filling end connected to said reservoir; and

a welded seam on said filling end for sealing said container, wherein said welded seam is a metal-to-metal weld.

2. The container of claim 1, wherein two welded seams are used to seal the container, said two welded seams overlapping one another.

3. The container according to claim 2, wherein said two welded seams are angled.

4. The container according to claim 1, wherein said dispensing end comprises an integrally formed nozzle with an integrally formed seal.

5. The container according to claim 1, wherein said container is in the shape of a tube.

6. The container according to claim 1, wherein said container is a flexible pouch having a plurality of sides.

7. The container according to claim 6, wherein said flexible pouch has two separate compartments.

8. The container according to claim 6, wherein said flexible pouch is in the shape of a square.

9. The container according to claim 6, wherein said flexible pouch is in the shape of a triangle.

10. The container according to claim 1, wherein said container is comprised of aluminum.

11. The container of claim 1, wherein said welded seam is an ultrasonically welded seam.

12. The container of claim 1, wherein said welded seam is a laser welded seam.

13. The container of claim 1, wherein said welded seam is an electron beam welded seam.

14. The container according to claim 1, wherein said container is constructed and arranged to attach to a bone cement mixer.

15. The container of claim 14, wherein said inlet of said container is threaded, and said inlet of said bone cement mixer has complementary threading so that said container is capable of being connected to said bone cement mixer.

16. The container according to claim 1, wherein said interior wall is uncoated.

17. A container for storing a liquid monomer of a two-part bone-cement system comprising:

a dispensing portion;

a reservoir having an inner surface that contacts said liquid monomer, said reservoir forming a wall for engaging said dispensing portion;

a filling portion for receiving said monomer, said filling portion connected to said reservoir; and

at least one welded seam for sealing said filling portion,

at least a portion of said inner surface of said reservoir being non-reactive with said liquid monomer, and said at least one welded seam being located adjacent said inner surface of said reservoir.

18. The container of claim 17, wherein said inner surface is uncoated.

19. The container of claim 1, wherein two welded seams are used to seal the container, said two welded seams overlapping one another.

20. The container according to claim 19, wherein said two welded seams are angled.

21. The container according to claim 17, wherein said dispensing portion comprises an integrally formed nozzle with an integrally formed seal.

22. The container of claim 17, wherein said welded seam is selected from the group consisting of an ultrasonically welded seam, a laser welded seam, and an electron beam seam.

23. The container of claim 17, wherein said container is comprised of aluminum.

24. A method for packaging a liquid monomer of a two-part bone cement system in a container, comprising:

forming an aluminum sheet having a surface for contacting said liquid monomer into a container having a filling portion end and a dispensing portion end;

filling said container with said liquid monomer through said filling portion; and

welding a seam on said filling portion of said container to seal said container with said liquid monomer therein.

25. The method of claim 24, wherein said welding includes providing two weld seams on said filling portion.

26. The method of claim 24, wherein said welding of two weld seams further includes overlapping said two welded seams.

27. The method of claim 24, wherein said welding is performed by a method selected from the group consisting of ultrasonic welding, electron beam welding, and laser welding.

28. The method of claim 24, wherein said welding is a metal-to-metal weld.