The present invention relates to a bone fiber composition having a varying physical characteristic and to an apparatus and method for preparing a bone fiber composition having a varying physical characteristic. More particularly, the present invention includes a bone fiber composition having at least different lengths, widths, and/or thickness, and to an apparatus capable of producing a bone fiber composition having at least different lengths, widths, and/or thickness.
The present invention is directed to the field of biocompatible materials for use in forming or filling voids, and voids in devices, for implantation in animals and humans. More particularly, the present invention is directed to an implantable tissue graft/implant formed from an allogeneic biocompatible human bone that is capable of being formed into a variety of tissue implants or compositions having different properties and different shapes. The present invention is useful because it provides a fiber composition that is easily transportable and stored. The fiber composition is then able to be formed by a surgeon into an implantable device, composition, or structure, having a conformable shape that is versatile in its ability to be formulated into a variety of implants or grafts that can be used in the treatment of a variety of medical conditions patients.
Conventional treatments for bone defects caused by various types of injuries or congenital abnormalities include the use of biocompatible on-organic materials and biocompatible organic materials. Non-organic materials include devices, materials and compositions made from metals such as titanium, or materials such as ceramics and polypropylene. A shortcoming of such non-organic devices includes an incompatibility between the non-organic device properties and the host tissue, which causes the non-organic device to loosen at the interface between the host tissue and the non-organic device. Additionally, it is common for non-organic devices to become encapsulated by the host tissue, which increases the risk of infection and rejection.
One solution to the above identified problems was the use organic materials in place of or in combination with metal, ceramic, or polypropylene implants. The use of organic materials include the use of allograft bone material. Under the proper conditions, and under the influence of osteogenic substances, implants made of allograft bone can act as the scaffolding for remodeling by the host's body. These organic implants have the benefit of functioning both structurally and biologically similar to the host tissue. Further, they allow cellular recruitment through the natural openings and proteins present in the bone matrix and allow the graft to be replaced by natural host bone.
While allograft bone fibers are very useful, they have traditionally been made by processes that create shortcomings in their final product. For instance, allograft bone fibers are generally made by using grinders or shredders that create fibers or powders having generally uniform characteristics (e.g., length, width, and thickness). The uniformity is dissimilar to naturally occurring collagen fibers present along the long axis of cortical bone.
It is an object of the present invention to have a novel composition and an apparatus, and method of preparing an allograft bone fiber having varying characteristics that can be formed into an implant or combined with a with improved cellular in-growth properties.
The applicants have discovered a novel device, apparatus, system, and process of making biocompatible, moldable, allograft material that is formable into an implant having enhanced surface area and entanglement properties for improved cellular infiltration. The present invention provides for an improved composition, device, apparatus, system, and method or process of making implantable materials for use in tissue regeneration in animals and humans. The apparatus of the present invention can manually and/or automatically convert allograft donor bone material into a fiber or shaving composition having at least two different characteristics, including having at least two different lengths, widths, and/or thickness. For example, the fibers of the composition can have at least two different lengths and at least two different widths, or it can have at least two different lengths and at least two different thicknesses. The present invention contemplates any configuration of fiber formation that includes at least two different characteristics.
In another aspect, the present invention is directed to a device, apparatus, system, and process of making an allograft bone fiber composition having at least two different characteristics that can be combined with an aqueous carrier to create a formable/moldable material. The formable/moldable material can then be implanted or combined with another material or device and then implanted into a patient. Alternatively, the fiber composition of the present invention can be combined with an aqueous carrier formed into an implantable structure or device and then dried into a predetermined shape for implantation. The shape of the tissue graft/implant of the present invention includes a strip, a sheet, a disc, a molded 3D shaped object, a plug, and a wedge.
Ideally, any cortical human bone will be suitable for use in the formation of the fiber composition of the present invention, including at least portions of all the long bones of the human body. Preferably, although not exclusively, the compact portion of the diaphysis of the human long bone.
Prior to the processing of any donor bone material in the device of the present invention, the donor bone material is debrided and washed to remove connective tissue, lipids, blood, and other non-bone tissues. The bone is subsequently demineralized in acid (such as hydrochloric acid or acetic acid). The demineralized bone is then processed by a fiber production apparatus that creates fibers having at least two different characteristics. After the fibers are produced, they undergo acid neutralization and further washing steps to remove any remaining residual non-bone tissues. The fibers are then freeze-dried and packaged into a final vial or jar for distribution to the end-user.
Any of the compositions of tissue graft/implants of the present invention may include collagen fibers, growth factors, antibiotics, cells, or particles such as demineralized bone matrix (DBM), mineralized bone matrix, cortical cancellous chips (CCC), crushed cancellous chips, tricalcium phosphate, hydroxyapatite, or biphasic calcium phosphate (wherein the latter is the combination of tricalcium phosphate and hydroxyapatite) or a combination thereof.
The fiber composition of the present invention, either alone or in a composition, is particularly suited for treating bone trauma, bone disease, bone defects, artificial arthrodesis, or for other treatments where new bone formation and/or repair of bony defects is desired. The fiber composition may be completely or partially demineralized and may be combined with other forms of demineralized bone matrix (“DBM”), mineralized bone matrix, CCC, crushed cancellous chips, tricalcium phosphate, hydroxyapatite, or biphasic calcium phosphate dispersed in the matrix.
The fiber composition of the present invention, either alone or in a mixture, is advantageous because it can be formed/molded, and the resulting shape implanted. The molded implantable material is porous and has a significant surface area and fiber entanglement that tis particularly well suited for the infiltration by colonizing cells (e.g., osteoconduction). The structure of the molded or implanted fiber composition can also be used for the storage and release of materials such as seeded cells, growth factors, and chemotactic agents to attract desired cells (e.g., osteoinduction), including proteins natively present and bound to the bone matrix, such as bone morphogenetic proteins (BMP's).
When the fiber composition or implant of the present invention is to be used to treat bone trauma, disease and defects, artificial arthrodesis and for other treatment where new bone formation is desired, it is optionally seeded with osteogenic cells. Optionally, the fiber composition or implant of the present invention is seeded with stem cells that will provide a natural distribution of the native cells necessary for restoration of the injury or defect at the site of implantation.
The fiber composition, and implants made therefrom, exhibit a great degree of tensile strength. They are readily stitchable and retain most of their tensile strength, even when rehydrated. In addition, upon hydration, the fiber composition and implants of the present invention are moldable and suitable for filling in irregular gaps or holes in the tissue to be repaired. Typically, the hydrated fibers of the composition are press-fitted by a surgeon into the defect or cavity to be filled.
It is also within the scope of the present invention that the fiber composition and the implants made therefrom can be utilized with a load-bearing member used in a spinal fusion. Suitable load bearing members include hollow spinal cages, hollow dowels, C-shaped and D-shaped spacers, and other devices known in the art, having a pocket, chamber, or other mechanism for retaining the bone fibers or molded implant of the present invention. Typically, the load-bearing member has a compressive strength of at least about 1,000 N. More typically, when utilized between lumbar vertebrae, the load-bearing member has a compressive strength of 3,000 to 11,000 N. When utilized between cervical vertebrae, the load bearing member has a compressive strength of about 1,000 to 3,000 N. Suitable load bearing members are known in the art and described in multiple U.S. patents, including, for example in U.S. Pat. Nos. 5,522,899, 5,785,710, 5,776,199 and 5,814,084, 6,033,438, 6,096,081, each of which is hereby incorporated by reference in its entirety
The method of making a composition of fibers having varying lengths, widths and/or thicknesses that are suitable for forming implants of improved porosity, surface area, and cell infusion comprises the steps of: obtaining a donor material. The donor bone material is then debrided and washed to remove connective tissue, lipids, blood, and other non-bone tissues. The bone is subsequently demineralized in acid (such as hydrochloric acid or acetic acid). The demineralized bone is then placed in a fiber production apparatus to produce fibers of the present invention. After the fibers are produced, they undergo acid neutralization and further washing steps to remove any remaining residual non-bone tissues. The fibers are then freeze-dried and packaged into a final vial or jar for distribution to the end-user.
In the above method, the matrix of allogeneic human bone comprises from about 1% to about 100% of the final weight of the composition or implant, more typically, from 50% to about 99% of the final weight of the implant, even more typically from 75% to about 99% of the final weight of the implant.
The fibers of the composition can be placed into a jar or vial and transported and stored until needed. The fibers are then able to be combined with an aqueous material/solution to create a formable/moldable mass that can be formed into any desired shape or configuration.
Prior to being used for implantation, the freeze-dried fiber composition of the present invention is removed from its sterile packaging and rehydrated by contacting it with an aqueous material/solution such as water, saline, blood, plasma, a buffered solution, or any other suitable liquid. The rehydrating liquid can also contain a growth factor, or a chemotactic agent as discussed above.
Alternatively, the fiber composition and the aqueous material can be made into a slurry that is an implantable tissue matrix of any size or shape. The slurry can be combined with other agents, such as DBM, CCC or a collagen (e.g., bone, tendon/ligament, fascia, and dermis) slurry before being placed into a mold. In one example embodiment, the slurry can be formed in an implantable film by applying a thin layer of the slurry into/on a flat plate that is allowed to either air dry, air dried with positive airflow, or dried in an oven, preferably a convection oven. The slurry can also be used to produce a sponge, a gasket, or any implantable shape. The slurry (neat or amended) is cast into a mold of the appropriate or desired shape, frozen or dried (to retain its size), and lyophilized. The resulting dried implantable film or shape is then ready for packaging and sterilization.
The above summary is not intended to limit the scope of the invention, or describe each embodiment, aspect, implementation, feature, or advantage of the invention. The detailed technology and preferred embodiments for the subject invention are described in the following paragraphs accompanying the appended drawings for people skilled in this field to well appreciate the features of the claimed invention. It is understood that the features mentioned hereinbefore and those to be commented on hereinafter may be used not only in the specified combinations, but also in other combinations or in isolation, without departing from the scope of the present invention.
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular example embodiments described. On the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims.
In the following descriptions, the present invention will be explained with reference to various exemplary embodiments. Nevertheless, these embodiments are not intended to limit the present invention to any specific example, environment, application, or particular implementation described herein. Therefore, descriptions of these example embodiments are only provided for purpose of illustration rather than to limit the present invention.
Dimensions and relative proportions of components are merely example embodiments and can be varied unless specifically limited in a given claim. Thus, the dimensions can be varied without departing from the scope of the invention.
The present invention of a fiber producing apparatus 10 that is configured for producing a fiber composition having varying characteristics. In one example embodiment, the fiber producing apparatus 10 is configured to produce a composition of fibers having that at least two-dimensional characteristics such as different lengths and different widths, different lengths and different thicknesses, or different widths and different thicknesses.
In the present invention, the term “fiber composition” refers to fibers having different physical characteristics, such as different lengths and different widths, different lengths and different thicknesses, or different widths and different thicknesses, and the like.
The apparatus, device or system 10 comprises an actuator assembly 12 that controls the production of the fiber composition, a carriage assembly 20 that is configured for holding a donor bone material that is used to produce the fiber composition, a drive assembly 60 that is operatively coupled to and extends between the actuator assembly 12 and the carriage assembly 20, and a support assembly 80 that is configured to support the actuator assembly 12, carriage assembly 20, and the drive assembly 60. The following specification describes example embodiments of the present invention that includes one or more of the above assemblies.
As illustrated in
In one example embodiment, the housing 13 can also include a display screen 15 that is able to display various operating parameters to an operator, including but not limited to a length, width, and thickness of the fibers being produced, an amount of production time remaining, a thickness of a donor tissue being processed, a speed of production, an amount of weight being used during production, and an amount/weight/volume of fibers produced. It should be appreciated that other production parameters/characteristics can also be displayed, and the above list should not be considered limiting. The housing 13 also includes an interior that is configured to at least hold a portion of a drive assembly 60, which is discussed in more detail below.
Referring to
As illustrated in
Referring back to
Referring to
The fiber cutting plate 29, combined with the capabilities of the actuator assembly 12, form a system 10 that can cut bone fibers having at least two or more dimensions. In one example embodiment of the present invention, there are a first plurality of blades 30a extending upwardly from an upper surface of the fiber cutting plate 29. There are also a second plurality of cutting blades 30b extending upwardly from the upper surface of the fiber cutting plate 29. The first plurality of cutting blades 30a have a height and width, when measured from the upper surface of the fiber cutting plate 29, then the plurality of second cutting blades 30b. The variation in the height and width of the first cutting blades 30a and the second cutting blades 30b provide bone fibers of at least two different thicknesses and two different widths.
In an example embodiment of the present invention, the placement of the cutting blades on the fiber cutting plate 29, along with a variation of stroke length, can add another dimensional difference to the bone fibers. For instance, the first plurality of cutting blades 30a are positioned and arranged proximate to one end of the fiber cutting plate 29 and the second plurality of cutting blades 30b are oriented generally toward a second end of the fiber cutting plate 29. Each of the first plurality of blades 30a and each of the second plurality of blades 30b have an adjacent opening, 32a and 32b respectively, which permit the cut fibers to pass through the fiber cutting plate 29.
In another example embodiment, as illustrated in
In another example embodiment, as also illustrated in
The same cutting blades 30a or 30b can also alternate directions such that the fiber cutting plate 29 has multiple cutting zones. This is illustrated by cutting blades 30aa, 30ab and 30bb, 30ba. Any number of zones and alternating cutting blade rows can be implemented.
A particular advantage of the present invention is that the alternating cutting direction of the cutting blades 30a, 30aa, 30ab, 30b, 30bb, and 30ba, enables cutting or severing of created fibers from the donor bone in both stroke directions (strokes occurring in the X-plane parallel to a horizontal table surface). The ability to cut or sever the fibers from the donor bone enables the ability to vary a bone fiber length by adjusting one or more stroke lengths.
The ability to cut or sever the bone fibers in both stroke directions in the X-plane can be improved by a weight or pressure provided in a Z-plane direction, which causes a compression of the bone against the fiber cutting plate 29. The weight or pressure may be adjusted to increase or decrease the Z-directional force. As a bone fiber is pulled out of a cutting blade (e.g., 30aa) hole or aperture it can expand and as the weight in the Z-plane causes a downward force it causes the attached bone fiber it to engage a cutting blade (e.g., 30ab) that is oriented in an opposition direction, thereby causing it to be severed from the donor bone.
As illustrated in
The fiber cutting plate 29 is removably positioned on the carrier plate 21 to aid in cleaning, sterilization, and replacement. The fiber cutting plate 29 may mate with one or more pins 26 extending from the carrier plate 21. In another example embodiment, fasteners are used to secure the fiber cutting plate 29 to the carrier plate 21.
In one example embodiment of the present invention, as illustrated in
In another example embodiment, as illustrated in
As illustrated in
As can be seen in
A plunger assembly 50 configured to hold the donor bone in the containment portion 42 is adjustably positioned above the top plate 40. The plunger assembly 50 comprises a pressure plate 52 and a press guide 54. The pressure plate 52 is configured to transfer pressure along the Z axis through the press guide 54 and onto the donor bone to generally fix the position of the donor bone in the containment portion 42 of the top plate 40.
In one example embodiment of the present invention, the press guide 54 comprises a toothed free end or surface that can pierce into the donor bone to fix it in place. The press guide 54 has a shape and configuration that enables to mate or extend into the containment portion 42 of the top plate 40. The press guide 54 may also be able to extend into the opening 27 of the securing member 25 as the donor bone draws near completion of its processing.
The top plate 40 and the pressure plate 52 have one or more holes 56a and 56b, respectively, extending through them. The holes 56a and 56b are aligned and configured to receive and slide over one or more guides 58a, 58b, and 58c coupled to and extending generally upward from the carriage assembly 20.
As mentioned above, the present invention includes a drive assembly 60 that is operatively coupled to the carrier plate 21 of the carriage assembly 20. The drive assembly 60 comprises a motor 61 coupled to a reciprocating drive shaft 62 that is operatively coupled to the channel 24 of the carrier plate 21. The motor 61 moves the drive shaft 62 and correspondingly the carrier plate 21 in a reciprocating motion along the X axis.
In one example embodiment of the present invention, as illustrated in
Referring back to
In another example embodiment, there can be two bottom supports, bottom support 82a positioned under at least a portion of the carriage assembly and support bottom 82b positioned at least partially under the drive assembly 60. The bottom supports 82a and 82b can be manufactured of different materials. For instance, bottom support 82a can be manufactured from a vibration reducing material, such as rubber, that reduces or absorbs any vibrations generated by the drive assembly 80. Bottom support 82b can be manufactured from any material, such as steel, that can be easily cleaned and sterilized after being in contact with the bone fibers. Similarly, the upright support members 84a and/or 84b can also be manufactured from similar or dissimilar materials that aid in stabilizing the system 10 and/or aid in cleaning the system 10. Various materials can be used and should be considered to be within the spirit and scope of the present invention.
A motor upright member or stand 85 can also be coupled to or mounted on the bottom support 82b. The motor upright member 85 is configured to position the motor 61 at a height that positions the drive shaft 62 parallel to the bottom supports 82a and 82b.
In one embodiment of the invention, the motor upright member 85 is adjustable to accommodate systems 10 of varying sizes. A height of the upright members 84a and 84b can also be adjustable to accommodate systems 10 of various sizes. The bottom support members 82a and 82b can be configured to permit various placement locations of the upright support members 84a and 84b. Varying the distance between the upright support members 84a and 84b adjusts a distance or space between the upright support members 84a and 84b. Additional upright support members can be added to the system 10 to accommodate drive shafts 62 and carriage assemblies 20 of varying lengths.
As illustrated in
As illustrated in
Referring to
An end of the rod 104 is coupled to a ram 106 that is configured for pressing against the pressure plate 52. In one example embodiment of the present invention, the ram 106 has a generally spherical shape. However, the ram 106 may have any size and shape configured to exert pressure onto the pressure plate 52.
The rod 104 of the piston 101 is extendable to exert pressure on the pressure plate 52 and retractable to relieve pressure from the pressure plate 52. As illustrated in
Pressure can also be applied to the pressure plate 52 by a manual mechanism. As illustrated in
In an alternative fiber formation apparatus 100, as illustrated in
In one example embodiment of the invention, the tabs 131a and 131b of the press support plate 122 can be formed as handles that can be coupled to or rested upon the upright support members 84a and 84b.
The bone press assembly 100 also comprises a bone housing or containment 140 having an aperture 142 extending generally through its center to provide access to the fiber cutting plate 29. As illustrated in
As illustrated in
The press assembly 100 also comprises a plunger 150 that is configured for being inserted into the aperture 142 of the bone housing 140. The plunger 150 includes a generally textured lower surface that is configured to engage the donor bone material and reduce its movement within the aperture 142 of the bone housing 140. The lower surface of the plunger 150 may comprise a plurality of patterned projections that are configured to penetrate the periosteum connected to the donor bone, thereby firmly resisting loss of grip, and thus loss of relative motion, between cutting plate 29 and the donor bone material.
The lower surface of the plunger 150 can also include a plurality of teeth capable of engaging with the surface of the donor bone material or periosteum. Other textured configurations are also possible and should be considered to be within the spirit and scope of the invention.
The weights 124 are also provided to exert downward pressure on the plunger 150 causing it to engage with the surface of the donor bone, thereby causing it to be pressed against the cutting blades 30a and 30b of the fiber cutting plate 29. The weights 124 can include one or more holes 126 extending through them and are able to receive and move along one or more poles or pins 130. The poles 130 act as a guide for the one or more weights 124. In one example embodiment of the invention, the poles 130 can extend through the one or more holes 152 in the bone housing 140. The poles 130 can also extend into the upper or top surface of the press support plate 122. The passage of the poles 130 through the weights 124, the bone housing 140 and, optionally, the press support plate 122, provides precise uniform movement of the weights 124 onto the plunger 150 and engagement of the donor bone onto the fiber cutting plate 29.
In use, an operator places a donor bone in the containment portion 42 or a similar retaining member. The apparatus 10 or 100 is switched from an off-state to an on-state. An emergency button is checked to ensure it is deactivated prior to performing the fiber cutting process. An actuator control is activated to begin the fiber cutting process. In one example embodiment, two actuator controls are required to be activated to ensure an operator's hands are free from the cutting area.
An operator is than able to activate the plunger assembly 50, which moves the rod 104 and ram 106 toward the pressure plate 52. The press, plunger, or guide 54 is then pressed against the donor bone, which is pressed against the fiber cutting plate 29. The textured surface of the press guide 54 penetrates the periosteum, thereby firmly resisting a loss of grip, and thus a loss of relative motion between fiber cutting plate 29 and the donor bone.
The operator can then begin the fiber cutting process by activating the motor 61 that is operatively coupled to the carriage assembly 20. The motor 61 moves the carriage assembly 20, including, the fiber cutting plate 29 and its blades 30a, 30aa, 30ab, 30b, 30bb, and 30ba, in a reciprocating motion. The blades 30a, 30aa, 30ab, 30b, 30bb, and 30ba cut fibers having dimensions consistent with the dimensions of the blades 30a, 30aa, 30ab, 30b, 30bb, and 30ba, the length of the strokes of the movement of the carriage assembly 20, and the amount of pressure applied to the donor bone against the cutting plate 29. As the donor bone is cut, grated, or shredded, the pressure or weight continues to increase, thereby pushing the donor bone against the fiber cutting plate 29 until the donor bone reaches a predetermined minimum thickness. Once the predetermined minimum thickness is reached the apparatus 10 or 100 stops and an operator can remove any remaining donor bone from the containment portion 42.
As fibers having different dimensions are cut, they can fall into a collection assembly 180, as illustrated in
The apparatus 10 or 100 of the present invention includes, but is not limited to, the following controls. 1) a first stroke-length control, a second stroke-length control, a speed control, a weight or pressure control, a depth control, and the like. The apparatus 10 or 100 can display parameters (such as those of the listed control) on the display 15. Other parameters can also be displayed and should be considered to be within the spirit and scope of the invention.
The first stroke and the second stroke of the apparatus 10 and 100 can be set to create varying lengths of bone fibers. For instance, the first or outward stroke can be set to 3 mm while the second or inward stroke can be set to 1 mm. As described above, the first plurality of cutting blades 30a can have a height and/or width different than the second plurality of cutting blades 30b. As a result, bone fibers having varying lengths and different thicknesses and/or widths are produced. Different blades 30a, 30aa, 30ab, 30b, 30bb, and 30ba with different cutting blade configurations can be used to make or create a greater variety of bone fibers. The different blades 30a, 30aa, 30ab, 30b, 30bb, and 30ba can be arranged in different areas or zones. The blades 30a, 30aa, 30ab, 30b, 30bb, and 30ba can also be arranged in zones facing each other, as particularly illustrated in
The apparatus 10 or 100 can be preprogrammed to vary stroke lengths and the pressure applied to the donor bone. In one example embodiment, the stroke lengths and pressures can be randomly varied throughout the cutting process to provide a fiber composition that is completely random and provides a potentially more realistic or natural fibrous consistency.
While the invention has been disclosed as cutting, shredding, or grating donor bone material it is within the spirit and scope of the invention that any material that can be cut, shredded, or grated can be used in the apparatus 10 or 100 of the present invention.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it will be apparent to those of ordinary skill in the art that the invention is not to be limited to the disclosed embodiments. It will be readily apparent to those of ordinary skill in the art that many modifications and equivalent arrangements can be made thereof without departing from the spirit and scope of the present disclosure, such scope to be accorded the broadest interpretation of the appended claims so as to encompass all equivalent structures and products. An example of this would be accomplishing relative motion between the cutting blade and bone other than reciprocating linear motion by deploying a rotational design where the bimodal cutting teeth travel in a circular path and the bone shaft is held in contact with the blade with a variable amount of force to produce a fiber. Moreover, features or aspects of various example embodiments may be mixed and matched (even if such combination is not explicitly described herein) without departing from the scope of the invention.
This application claims the benefit of priority from U.S. Provisional Application No. 63/141,404, filed Jan. 25, 2021, titled “APPARATUS AND METHOD OF PREPARING BONE FIBERS,” the entire contents of which are hereby incorporated by reference herein.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/US2022/013773 | 1/25/2022 | WO |
Number | Date | Country | |
---|---|---|---|
63141404 | Jan 2021 | US |