Abstract:
A vacuum package system for hydrating and/or rehydrating orthopedic graft materials, such as allograft materials, xenograft materials, and synthetic materials, is described. The system primarily includes a container, which includes a dividing device for dividing the container into first and second compartments and for isolating the compartments from one another, the first compartment containing a liquid component and the second compartment containing either dry porous and/or dehydrated orthopedic graft material under vacuum with a tubular member. The elongated tubular member extends from, and is in communication with, the second compartment. The tubular portion defines vacuum reservoir device is disposed within the first compartment and is in communication with the second compartment. The vacuum reservoir device is capable of taking up substantially all residual interstitial gases and thereby ensuring thorough infusion of the liquid component into the orthopedic graft material component upon release of the dividing device so as to form either a hydrated and/or rehydrated orthopedic graft material. An optional gas permeable but liquid impermeable membrane is disposed between the second compartment and the pocket portion.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part application of U.S. patent application Ser. No. 09/908,151, filed on Jul. 18, 2001 and issued Nov. 18, 2003 as U.S. Pat. No. 6,648,133. The disclosure of the above application is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to orthopedic materials and packaging therefor, and more particularly to a device and method for hydrating and/or rehydrating orthopedic graft materials, such as allograft materials, xenograft materials, and synthetic materials. Specifically, a vacuum package system is provided for dehydrated, e.g., freeze-dried, orthopedic graft materials, as well as dry porous orthopedic graft materials, e.g., calcium-phosphate-based materials, which allows for liquid materials to rapidly and thoroughly infuse within the pores of either type of orthopedic graft material so as to form hydrated and/or rehydrated orthopedic graft materials. 
     BACKGROUND OF THE INVENTION 
     Allografting is one of the most widely used orthopedic transplantation techniques currently being used by orthopedic surgeons. Its main use is in the field of revision joint replacement, particularly total hip replacement, although its use is also widespread in the treatment of many different types of bone defects as well. 
     An allograft is generally defined as a graft of tissue, such as bone tissue, from a donor of one species and grafted into a recipient of the same species. Allograft tissue is typically derived from cadaveric donors (i.e., from deceased donors). 
     One type of allograft tissue is generally referred to as structural allograft tissue, which typically consist of blocks of bone or other types of tissue that can fastened adjacent to or onto one or more surfaces of the bone defect. These blocks can also act as bulk supports to orthopedic prostheses or other types of graft tissue. These blocks can be shaped into any number of appropriate shapes and configurations in order to suit the particular clinical needs of the patient. 
     In order to preserve the useful shelf life of allograft tissue, as well as to inhibit bacterial growth within the allograft tissue, it is becoming common practice to dehydrate the allograft tissue, especially by freeze-drying. Freeze-drying quickly removes virtually all of the moisture within the allograft tissue, thus inhibiting any subsequent bacterial growth. However, prior to employing the allograft tissue in a surgical setting, it is generally necessary to re-hydrate the freeze-dried allograft tissue with some sort of fluid, such as sterilized water, saline, or the like. 
     Typically, the freeze-dried allograft tissue is removed from its protective packaging and either introduced into a liquid source or the liquid source is introduced onto the freeze-dried allograft tissue. This is a cumbersome and sometimes sloppy process that unnecessarily exposes the freeze-dried allograft tissue to atmospheric pathogens during the rehydration process. Additionally, this haphazard process does not ensure that the liquid material will thoroughly infuse into the pores of the allograft tissue. 
     Additionally, xenograft materials (e.g., non-human or animal-based graft materials) as well as synthetic materials (e.g., ceramic graft materials such as calcium-based materials, calcium-phosphate-based materials, calcium-sulfate-based materials, calcium-sodium-phosphate-based materials, as well as many others) have been used as orthopedic graft materials as well. However, these materials, must also be either rehydrated, in the case of dehydrated xenografts, or hydrated in the case of dry porous synthetic materials. Therefore, the same general problems described above are also encountered with these materials as well. 
     Therefore, there still exists a need for an apparatus and method for either hydrating dry porous orthopedic graft materials or rehydrating dehydrated orthopedic graft materials such that the respective orthopedic graft materials can be either hydrated and/or rehydrated in a sterile, efficient, and cost-effective manner. 
     SUMMARY OF THE INVENTION 
     In accordance with one embodiment of the present invention, a container for storing and rehydrating orthopedic materials is disclosed. The container is fluidly divided by a clamping mechanism to form a first and second cavity. Disposed within and under a vacuum in the first cavity is a syringe that contains the orthopedic material. The syringe body functions as a vacuum reservoir to pull fluid from the second cavity into the first cavity. This fluid rehydrates the orthopedic material. 
     In another embodiment of the invention, a container is provided which has first and second chambers. Disposed between the chambers is a cylindrical member which holds orthopedic materials. The cylinder functions as a vacuum reservoir. A clamp is provided which separates liquid stored in the second chamber from the cylinder. Upon release of the clamp, the fluid flows from the second chamber into the orthopedic material. 
     Further disclosed is a method for reconstituting an orthopedic material. The method has the steps of providing a container which has first and second cavities. Disposing a cylindrical member between the first and second cavities so as to fluidly couple the cavities. The cylindrical member having biological materials disposed therein. Separating the cylinder from the first cavity. Applying a vacuum to the second cavity, and filling the first cavity with a liquid. The first cavity is then fluidly coupled to the cylindrical member whereupon the liquid rapidly migrates into the cylindrical member and thoroughly infuses into the orthopedic graft material so as to form a hydrated orthopedic a graft material. 
     A more complete appreciation of the present invention and its scope can be obtained from the following detailed description of the invention, the drawings, and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1  illustrates a perspective view of a packaging system for orthopedic graft materials, in accordance with one embodiment of the present invention; 
         FIG. 1   a  illustrates a perspective view of a packaging system for morselized orthopedic graft materials, in accordance with one embodiment of the present invention; 
         FIG. 1   b  illustrates a perspective view of a packaging system for machined shape synthetic orthopedic graft materials, in accordance with one embodiment of the present invention; 
         FIG. 2  illustrates a top plan view of a packaging system for orthopedic materials, in accordance with one embodiment of the present invention; 
         FIG. 3  illustrates a side elevational view of a packaging system for orthopedic materials, in accordance with one embodiment of the present invention; 
         FIG. 4  illustrates an exploded view of a clamp of the packaging system for orthopedic materials, in accordance with one embodiment of the present invention; 
         FIG. 5  illustrates a partial cross-sectional view of the clamp of the packaging system for orthopedic materials, in accordance with one embodiment of the present invention; 
         FIG. 6  illustrates a perspective view of a material introduction device and the packaging system for orthopedic materials, in accordance with one embodiment of the present invention; 
         FIG. 7  illustrates a top plan view of the initial infusion process of the dehydrated orthopedic graft material, in accordance with one embodiment of the present invention; 
         FIG. 8  illustrates a perspective view of the initial infusion process of the dehydrated orthopedic graft material, in accordance with one embodiment of the present invention; 
         FIG. 9  illustrates a top plan view of the completion of the infusion process of the dehydrated orthopedic graft material, in accordance with one embodiment of the present invention; 
         FIG. 10  illustrates a perspective view of the completion of the infusion process of the dehydrated orthopedic graft material, in accordance with one embodiment of the present invention; 
         FIG. 11  illustrates a perspective view of the opening of the packaging system for orthopedic materials, in accordance with one embodiment of the present invention; 
         FIG. 12  illustrates a perspective view of the rehydrated orthopedic graft material being removed from the packaging system for orthopedic materials, in accordance with one embodiment of the present invention. 
         FIG. 13  represents a perspective view of a packaging system for an orthopedic graft material in accordance with another embodiment of the invention; 
         FIG. 14  represents a top view of the packaging system shown in  FIG. 13 ; 
         FIG. 15  represents a side view of a packaging system shown in  FIG. 13 ; 
         FIG. 16  represents a perspective view of the introduction of reconstitution liquid into the packaging system shown in  FIG. 13 ; 
         FIG. 17  represents a perspective view of the initial infusion process of the rehydration of the allograph material in accordance with one embodiment of the present invention; 
         FIG. 18  represents a perspective view of the opening of the packaging system shown in  FIG. 13 ; and 
         FIG. 19  represents a perspective view of a syringe shown in  FIG. 1  having reconstitution bone allograph material. 
     
    
    
     The same reference numerals refer to the same parts throughout the various Figures. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is useful for the hydration and rehydration of any number of different orthopedic graft materials, such as but not limited to allograft materials (e.g., human-based graft materials), xenograft materials (e.g., non-human or animal-based graft materials), and synthetic materials (e.g., ceramic graft materials such as calcium-based materials, calcium-phosphate-based materials, calcium-sulfate-based materials, calcium-sodium-phosphate-based materials, as well as many others). 
     These various orthopedic graft materials, especially the synthetic materials, can be shaped into any number of configurations, including but not limited to blocks, rings, struts, machined shapes, chips, morsels, granules, and so forth. 
     Furthermore, ceramic cements, such as but not limited to tetracalcium phosphate/tricalcium phosphate cement, calcium sodium phosphate cement, and calcium sulfate, may also be used as orthopedic graft materials. The powder portion would typically be mixed with a citric acid solution or a citrate salt solution in order to form a thick paste which hardens in 5 to 15 minutes. 
     By the term “orthopedic graft material,” as that term is used herein, it is meant any orthopedic material that is capable of either being hydrated and/or rehydrated. By the term “rehydrated,” as that term is used herein, it is meant either hydrated and/or rehydrated. 
     The hydrating and/or rehydrating material may be comprised of any number of aqueous-based liquids, such as water, saline, or the like. Additionally, biologically active materials (e.g., therapeutic and/or prophylactic), such as but not limited to antibiotics, platelet concentrates, bone growth factors, may be introduced into the hydrating and/or rehydrating material, or alternatively, may comprise a portion of, or the entire volume of, the hydrating and/or rehydrating material. 
     Referring now to  FIGS. 1–3 , a packaging system for orthopedic materials is shown designated generally by the reference numeral  10 . The packaging system  10  is somewhat similar to the packaging systems described in U.S. Pat. Nos. 5,370,221 and 5,398,483, the entire specifications of which are incorporated herein by reference. 
     The packaging system  10  of the present invention primarily includes a preferably flexible container  12 , a divider or clamp  14 , a tubular portion  16 , a vacuum reservoir  18 , and an optional gas permeable membrane  20 . Preferably, the optional gas permeable membrane  20  is also substantially liquid impermeable. By way of a non-limiting example, the material to be stored can be either substantially solid allograft materials ( FIG. 1 ), morselized allograft materials ( FIG. 1   a ), xenograft materials (not shown), synthetic materials ( FIG. 1   b ), as well as other types of orthopedic graft materials. 
     The container  12  preferably includes a front panel  22  and a rear panel  24 , each made of a thin generally impervious flexible film or laminate. The exact nature of the thin generally impervious flexible film or laminate to be used with the container  12  of the present invention depends upon the nature of the materials to be stored and the conditions under which the materials will be combined and used. For many applications and materials, films and/or laminates of polyethylene, fluoropolymer, nylon, ethyl vinyl alcohol, metal foil, laminated glass and various combinations of the foregoing materials may be used. However, it will be appreciated that other suitable materials may also be used as well. 
     Additionally, while the container  12  is shown as being substantially rectangular, it is to be understood that the present invention is applicable to flexible containers of other shapes, such as square, triangular or trapezoidal and may have curved edges. The panels  22  and  24  can be formed from a single sheet of flexible film sealed to each other at a bottom edge  26  and side edges  28  and  30 . 
     As noted, the container  12  further includes a tubular portion  16  which is sealed along its continuous edge  32  similar to the edges  26 ,  28 , and  30 . Disposed within the tubular portion  16  is the vacuum reservoir device  18 , the purpose of which will be more fully explained herein. 
     The clamp  14  is arranged to provide a temporary seal of the inner surfaces of the panels  20  and  22  to each other along a line extending from an initial point  34  on the sealed edge  28  to a terminal point  36  on the sealed edge  30  to form a first or upper compartment  38  and a second or lower compartment  40 . As will be appreciated by those skilled in the art, the clamp  14  is preferably placed on the container  12  prior to being filled with either the liquid component or the orthopedic graft material component. 
     Referring to  FIGS. 4–5 , the clamp  14  comprises a C-shaped outer retention member  42  and an I-shaped inner retention member  44  which partially fits within the hollow of the C-shaped outer retention member  42 . When the clamp  14  is assembled with respect to the container  12  as shown in  FIG. 5 , the outer retention member  42  is positioned on the outside of the rear panel  22  and the inner retention member  44  is positioned on the outside of the front panel  20  such that the panels  20  and  22  are pinched together along a pair of parallel lines extending from the initial point  34  to the terminal point  36 . The inner retention member  44  has a contoured upper end which fits within the inner hollow of outer retention member  42  and has a thickness substantially equal to the inner distance between the open ends of the C-shaped section of the outside retention member  42  so that a double thickness of panels  20  and  22  is tightly compressed along a pair of parallel lines to form an effective seal or divider. The outer retention member  42  is made of a resilient material so that the inner retention member  44  may be forced into position therein by placing it over the entire length of the opening of the outer retention member  42  and then pressing it into place. Inner retention member  44  has a contoured upper end which can open the open ends of the C-shaped section of the outside retention member  42  to accommodate the inner retention member  44 . 
     The nature of the clamp  14  may also vary. The clamp  14  described in connection with the present invention consisting of an I-shaped inner retention member  44  and a C-shaped outer retention member  42 , is preferred because of its simplicity and ease of handling. However, other types of clamps suitable for applying pressure to the container  12  may also be used. In addition, it is possible to replace the clamp  14  with an additional separation seal or divider (not shown). In this embodiment, the separation seal can be either a heat seal or an adhesive seal to separate the upper compartment  38  from the lower compartment  40 . The strength of this separation seal must be such that it can be broken by placing pressure on either of the compartments  38  and  40  without damaging the panels  20  and  22 . This separation seal may also be used in conjunction with the clamp  14 . 
     The method of packaging the components of the orthopedic graft materials within the packaging  12  will now be described. The side edges  26  and  28  of the front panel  20  and the rear panel  22  are typically secured together by heat sealing, although other means of sealing may be used as well, such as adhesives. The clamp  14  is then placed over the front panel  20  and the rear panel  22  so as to form a temporary seal between the front panel  20  and the rear panel  22  and partially form the upper compartment  38  and the lower compartment  40  under environmentally controlled conditions. In certain circumstances, it will be necessary to position the orthopedic graft material D within the lower compartment  40  prior to heat sealing of the respective edges of the lower compartment  40  due, in part, to the size and configuration of the orthopedic graft material. In that circumstance, once the orthopedic graft material D is properly positioned, a heat seal then closes the lower compartment  40 . The container  12  is then sterilized employing gamma radiation, electron beam or other means. The liquid component L (e.g., water, saline, or the like) is then filled into the upper compartment  38  under aseptic conditions and then the upper compartment  38  is closed by the seal  24 . However, it should be noted that it is not necessary that the liquid component L be added at the same time the orthopedic graft material D is introduced. For example, the liquid component L can be introduced immediately before the infusion process is to take place, for example, in the operating room. Additionally, a port device  46  may be provided on the upper compartment  38  in order to introduce additional materials into the liquid component L (via syringe  48 ), such as but not limited to biologically active materials, as shown in  FIG. 6 . Preferably, the port device  46  is self-sealing, or is provided with a cap or similar device, so as to prevent any leakage problems. 
     The main benefit of the present invention is that it provides a system for in situ mixing of the two components to produce a rehydrated orthopedic graft material. This is achieved by maintaining the lower compartment  40  under vacuum. This vacuum condition is facilitated by the presence of the vacuum reservoir  18  in the tubular portion  16 . The vacuum reservoir  18  preferably has a sufficiently large volume to take up the residual gases which will be replaced in the interstitial voids between the particles of the orthopedic graft material by the liquid component upon release or breaking of the seal between the first and second compartments. The purpose of the optional gas permeable membrane  20  is to allow air to be drawn out of the lower compartment  40  (e.g., during the creation of the vacuum condition), while preventing any liquid or particulate matter from penetrating into the tubular portion  16  or leaving the graft material. 
     The force which transfers the liquid component L into the second compartment  40  to combine with the orthopedic graft material component D is thus the pressure differential between the atmospheric pressure acting on the walls of the first compartment  38  and the pressure prevailing in the second compartment  40 . The function of the vacuum reservoir  18  is to maintain a sufficiently low pressure in the second compartment  40  until the orthopedic graft material component D has been completely and thoroughly infused by the liquid component L. Once the clamp  14  has been removed, the liquid component L will rapidly flow into the second compartment  40 , completely and thoroughly infusing the orthopedic graft material component D, as shown in  FIGS. 7–8 . Once the infusion process is complete, the hydrated (or rehydrated) orthopedic graft material R will be ready for immediate implantation, as shown in  FIGS. 9–10  Following the infusion process, the container  12  holding the hydrated/rehydrated orthopedic graft material R is opened (see  FIG. 11 ) and the hydrated/rehydrated graft material R is removed (see  FIG. 12 ), preferably with a sterile instrument such as a forceps  50 , and is now ready for immediate affixation onto a bone defect, for example. 
     Referring to  FIGS. 13–15 , a packaging system for orthopedic materials is shown designated generally by the reference numeral  60 . The packaging system  60  of the present embodiment includes a flexible container  62 , a divider or clamp  64 , and a tubular port  65 . Disposed within the flexible container is a syringe  20  containing biocompatible material  67  of morselized allograph materials, xenograft materials, synthetic bone cement, or any other types of orthopedic graft materials. 
     The container  62  contains a front panel  66  and a rear panel  68 . The exact nature of the layers  66  and  68  depend upon the nature of the materials to be stored and the nature of the environmental conditions the system  60  will be subject to. The container  62  further defines a proximal end  69  and a distal end  70 . Disposed between the proximal end and distal ends  69  and  70  at a medial location  72  is the clamp  64  which functions as described above. Defined between the clamp  64  and the proximal end  68  is a first cavity  74  which is configured to hold reconstitution liquid  76 . Disposed between the clamp and a distal end  70  is a second cavity  78  which holds the syringe  20 . 
     The second cavity  78  can optionally have a first portion  79  adjacent to the medial location  72  having a radius which comports to the outer diameter  71  of the syringe. In this regard, as described below, a body portion  82  of the syringe  20  functions to act as a fluid couple between the first cavity  74  and the second cavity  78 . 
     The body  82  further acts as a vacuum reservoir  18  which obviates the need for a separate vacuum holding component. The first portion  79  functions to seal the syringe  20  to an internal surface of the container  62 . The vacuum reservoir  18  of the syringe  20  functions to provide a vacuum sufficient enough to remove any residual gases within the orthopedic material  67  or the reconstitution liquid. Disposed at a proximal end  84  of the generally cylindrical body  82  is the orthopedic material  67 . Disposed in the aperture  86  formed by the distal end  88  of the cylindrical body  82  is a plunger  90 . The plunger  90  has a cylindrical portion  92  which comports to an interior surface  94  of the cylindrical body  82  and further defines a plurality of through passages  94   a – 94   e , which function to allow gases to pass through the orthopedic material  67  into the second cavity  78 . Optionally, the plunger has a locking device  91  which functions to resist the movement of the plunger  90  during the reconstitution of the orthopedic material  67 . This locking device  91  can take the form of foam or a releasable polymeric clasp. 
     Disposed between the plunger  90  and the orthopedic material  67  is a layer of gas permeable material  96  which functions to allow the air to flow through and out of the orthopedic material  67  into the second cavity  78  and into the vacuum reservoir device  18  as previously described. Further, the gas permeable material  96  functions to prevent the reconstitution liquid from being drawn out of the orthopedic material or entering the body of the syringe  20 . Optionally, a second gas and reconstitution liquid permeable membrane  97  can be disposed at the proximal end  84  of the syringe  20  so as to hold the orthographic material in the syringe  20 . 
     The force needed to transfer the liquid into the syringe  20  to combine with the orthopedic material  67  is the difference between the atmospheric pressure acting on the first cavity  74  and the pressure within the cavity  78 . As previously described, the function of the vacuum reservoir  10  within the syringe  20  is to maintain a sufficiently low pressure in the second cavity  78  so as to allow the proper amount of liquid to be pulled into the orthopedic material  67  in the syringe  20 . 
     The infusion of the orthopedic material  67  is shown in  FIGS. 16 and 17 . It should be noted that the first cavity  74  can either be prepackaged with reconstitution fluid  76 , or can have the reconstitution fluid  76  injected through the port  65 . The use of the clamp  64  allows the mixing of various biological material such as platelets or antibiotics into the reconstitution liquid  76  prior to infusion. It additionally is envisioned that the reconstitution liquid can be injected directly into the port  65  without the use of the clamp  64  for direct rehydration of the material  67 . Once rehyrdration is complete, the orthopedic material  67  is ready for implantation. As is shown in  FIG. 18 , the syringe is removed from the container  62 . The locking device  91  is removed from the plunger  90 . The plunger  90  can now be used to implant the orthopedic material  67  or bone cement material as is needed. It is envisioned that injection heads (not shown) can be coupled to the syringe  20  to assist in the interoperative use of the orthopedic material  67  or the bone cement. 
     The foregoing description is considered illustrative only of the principles of the invention. Furthermore, because numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and process shown as described above. Accordingly, all suitable modifications and equivalents that may be resorted to that fall within the scope of the invention as defined by the claims that follow.