VASCULARITY AFFINITY PRECURSOR STRUCTURE FOR MUSCULO-SKELETAL TISSUE HEALING

Abstract

The present invention relates to an implantable device configured to deliver, to an injured bone site, components for revascularisation and bone repair, the device comprising: a first osteoconductive scaffold component adapted to hold and deliver to the injured bone site, growth factors for inducing cellular events that initiate healing; and comprising a second osteoconductive scaffold component adapted to hold and deliver to the injured bone site, viable autologous osteogenic and/or angiogenic cells, and wherein the device also comprises a third scaffold component adapted to promote bone cell proliferation and vascularity, whereby the scaffold components provide a stable mechanical environment for promoting bone cell proliferation and vascularity. The present invention also relates to a method of manufacture of the implantable device.

Claims

1. An implantable device configured to deliver, to an injured bone site, components for revascularisation and bone repair, the device comprising: at least one osteoconductive scaffold component adapted to hold and deliver to the injured bone site, growth factors for inducing cellular events that initiate healing; at least one osteoconductive scaffold component being adapted to hold and deliver to the injured bone site, viable autologous osteogenic and/or angiogenic cells, and wherein the device also comprises a component adapted to promote bone cell proliferation and vascularity, wherein the at least one scaffold component provides a stable mechanical environment for promoting bone cell proliferation and vascularity.

2. The implantable device, as claimed in claim 1, configured to deliver, to an injured bone site, components for revascularisation and bone repair, the device comprising: a first osteoconductive scaffold component adapted to hold and deliver to the injured bone site, growth factors for inducing cellular events that initiate healing; and comprising a second osteoconductive scaffold component adapted to hold and deliver to the injured bone site, viable autologous osteogenic and/or angiogenic cells, and wherein the device also comprises a third scaffold component adapted to promote bone cell proliferation and vascularity, whereby the scaffold components provide a stable mechanical environment for promoting bone cell proliferation and vascularity.

3. The device as claimed in claim 1 wherein the third scaffold component comprises a biomimetic bone generating agent.

4. The device as claimed in claim 2 wherein the biomimetic bone generating agent comprises an inorganic bone precursor.

5. The device as claimed in claim 1 wherein the first scaffold component and the second scaffold component comprise a porous biomaterial.

6. The device as claimed in claim 5 wherein the porous biomaterial comprises a sponge; preferably, comprising a natural or synthetic hydrogel matrix for supporting 3D cellular growth throughout the scaffold component; and most preferably, comprises collagen, optionally, in the form of a layer of collagen.

7. The device as claimed in claim 5 wherein the first scaffold component and the second scaffold component varies in formulation and specification in order to optimize the environment and therapeutic effect for the molecules which each of the first and second scaffold components host.

8. The device as claimed in claim 5 wherein the first scaffold component comprises a first porous scaffold component having pores of a first size and the second scaffold component comprises a second porous scaffold component having pores of a second size, the pores being sized appropriately to hold and deliver the respective growth factors; and viable autologous osteogenic and/or angiogenic cells, which the respective scaffold components hold and deliver.

9. The device as claimed in claim 7 wherein the first scaffold component comprises the first porous structure having the first pore size adapted to hold and deliver to the injured bone site, growth factors for inducing cellular events that initiate healing.

10. The device as claimed in claim 7 wherein the second scaffold component comprises the porous structure having the second pore size adapted to hold and deliver autologous osteogenic and angiogenic cells.

11. The device as claimed in claim 8, wherein the first pore size is relatively small and the second pore size is relatively large whereby the relatively smaller pore size of the first scaffold sponge is adapted for holding and delivering the PRP and growth factors to the bone defect site and the relatively larger pore size of the second scaffold component is adapted for holding and delivering the osteogenic and/or angiogenic cells to the bone defect site.

12. The device as claimed in claim 10 wherein the first scaffold component comprises pores having a first pore size of 2-10 M and the second scaffold component comprises pores having a second pore size of 100-350 M.

13. The device as claimed in claim 1 wherein the device can be produced in shapes comprising of rectangles, squares, circles and cylinders.

14. The device in claim 1 wherein the device is adapted to be cut and sized depending on the requirement of the patient.

15. The device in claim 1 wherein the device is can be cut and sized to aid delivery through cannulated devices or similar, to the bone defect site.

16. The device as claimed in in claim 3 wherein the inorganic bone precursor comprises a calcium based compound.

17. The device as claimed in claim 16 wherein the calcium based compound comprises a biomimetic octacalcium phosphate compound; preferably, provided in granular form and having a particle size that is optimized for cell proliferation.

18. The device in claim 1 wherein the biomimetic bone generating agent (bone precursor) comprises a calcium phosphate based salt.

19. The device as claimed in claim 3, wherein the biomimetic bone generation phase comprises a calcium phase comprises any one or more selected from the following group of calcium compounds: octacalcium phosphate (OCP) and/or tri-calcium phosphate (TCP) and/or hydroxyapatite (HA) and/or dicalcium phosphate dihydrate (DCPD) and/or dicalcium phosphate anhydrous (DCPA) and/or amorphous calcium phosphate (ACP) and/or calcium carbonate.

20. The device as claimed in claim 16, wherein the biomimetic bone pre-cursor comprises octacalcium phosphate (OCP) in granular form, optionally, in combination with dicalcium phosphate dehydrate, with a particle size optimized for cell proliferation.

21. The device as claimed in claim 1 wherein the biomimetic bone generating agent is encapsulated within at least one scaffold component.

22. The device as claimed in claim 2, wherein the biomimetic bone generating agent is encapsulated within at least one of the first and second scaffold components.

23. The device as claimed in claim 2, wherein the biomimetic bone generating agent is provided between the first scaffold component and the second scaffold component.

24. The device as claimed in claim 23 wherein the biomimetic bone generating agent is provided as a layer between the first scaffold component and the second scaffold component.

25. The device in claim 2 or wherein the composition of the biomimetic bone precursor may be multiphasic.

26. The device as claimed in claim 1, wherein the or each osteoconductive scaffold comprises a biological material, preferably a porous biomaterial.

27. The device as claimed in claim 26 wherein the biomaterial is selected from the group consisting of: allograft or xenograft trabecular bone, demineralised bone matrix (DBM), collagen, hydroxyapatite (HA), polylactic or polyglycolic acid, bioactive glasses, calcium-based ceramics, hydrogel, and combinations thereof.

28. The device as claimed in claim 26 wherein the biomaterial is collagen, hydrogel or both collagen and hydrogel.

29. The device as claimed in claim 1, wherein the or each osteoconductive scaffold comprises a calcium based ceramic, preferably, comprising a calcium phosphate compound.

30. The device as claimed in claim 1, wherein biomimetic bone generation agent comprises a calcium compound, preferably, comprising any one or more selected from the following group of calcium compounds: octacalcium phosphate (OCP) and/or tri-calcium phosphate (TCP) and/or hydroxyapatite (HA) and/or dicalcium phosphate dihydrate (DCPD) and/or dicalcium phosphate anhydrous (DCPA) and/or amorphous calcium phosphate (ACP) and/or calcium carbonate.

31. An implantable device for musculo-skeletal tissue healing for bone repair and regeneration and comprises and/or is adapted to deliver the following components: Osteogenic Cells and/or angiogenic cells; at least one Osteoconductive Scaffold; at least one Growth Factor; and a favorable/stable mechanical environment.

32. The device as claimed in claim 31 wherein the device is configured to deliver said components, simultaneously, for bone repair and regeneration.

33. The device as claimed in claim 1, wherein the osteoconductive scaffold comprises a biological material, preferably a porous biomaterial and wherein the biomaterial is selected from at least of the following: allograft or xenograft trabecular bone, demineralised bone matrix (DBM), collagen, hydroxyapatite (HA), polylactic or polyglycolic acid, bioactive glasses, calcium-based ceramics, and hydrogel; and wherein a biomimetic calcium phosphate bone precursor is encapsulated within the osteoconductive scaffold for musculo-skeletal tissue healing.

34. The device as claimed in claim 1, wherein the materials are modified to allow addition of other factors including but not limited to pharmaceutical or medical devices.

35. The device as claimed in claim 34 wherein the additional factors comprise at least one selected from the following group: bone morphogenetic proteins, antibiotics, antifungals, antivirals, bisphosphonates, growth factors, hormones, proteins and other inorganic minerals.

36. The device as claimed in claim 1 wherein the growth factors are provided by Bone Marrow Aspirate (BMA) and/or Bone Marrow Aspirate Concentrate (BMAC) and/or viable platelet rich plasma (PRP) and the at least one scaffold component is adapted to hold the Bone Marrow Aspirate (BMA) and/or viable platelet rich plasma (PRP) and deliver the growth factors to the injured site.

37. The device as claimed in claim 1, wherein the autologous osteogenic and angiogenic cells are provided by Bone Marrow Aspirate (BMA) and/or Bone Marrow Aspirate Concentrate (BMAC).

38. The device as claimed in claim 36 wherein the BMA BMAC is collected preoperatively, grown/modified in the lab and used when needed during surgery.

39. The device as claimed in claim 1 wherein once the device has been implanted, mechanical fixing means may be used to fix the bone fracture in place if required.

40. The device as claimed in claim 39 wherein the fixing means comprises any at least one selected from the following group: secure pins, screws and orthopaedic fixing devices.

41. The device as claimed in claim 1, wherein different sized -TCP/OCP granules may be used to trap air bubbles between the first and second scaffold components to be utilized by the cells as needed.

42. The device as claimed in claim 1, wherein the scaffold component(s) are flushed with oxygen so that oxygen will be trapped within the fibers and can be utilized by the cells when needed.

43. The device as claimed in claim 1, wherein as the scaffold component(s), in the form of a collagen layer, is being manufactured, trapped air bubbles are retained in the scaffold component and said trapped air bubbles can be utilized by the cells if needed.

44. A method of manufacture of an implantable device configured to deliver, to an injured bone site, components for revascularisation and bone repair, the method comprising the following steps: providing at least one osteoconductive scaffold component adapted to hold and deliver to the injured bone site, growth factors for inducing cellular events that initiate healing; at least one osteoconductive scaffold component being adapted to hold and deliver to the injured bone site, viable autologous osteogenic and/or angiogenic cells, and providing a component adapted to promote bone cell proliferation and vascularity, whereby the at least one scaffold component provides a stable mechanical environment for promoting bone cell proliferation and vascularity.

45. The method of manufacture of an implantable device, as claimed in claim 44, the device being configured to deliver, to an injured bone site, components for revascularisation and bone repair, the method comprising the following steps: providing a first osteoconductive scaffold component adapted to hold and deliver to the injured bone site, growth factors for inducing cellular events that initiate healing; and providing a second osteoconductive scaffold component adapted to hold and deliver to the injured bone site, viable autologous osteogenic and/or angiogenic cells, and providing a third scaffold component adapted to promote bone cell proliferation and vascularity, whereby the scaffold components provide a stable mechanical environment for promoting bone cell proliferation and vascularity.

46. The method as claimed in claim 45 wherein the third scaffold component comprises a biomimetic bone generating agent.

47. The method as claimed in claim 46 wherein the biomimetic bone generating agent comprises an inorganic bone precursor.

48. The method as claimed in claim 44 wherein the first scaffold component and the second scaffold component comprise a porous biomaterial.

49. The method as claimed in claim 48 wherein the porous biomaterial comprises a sponge; comprising a natural or synthetic hydrogel matrix for supporting 3D cellular growth throughout the scaffold component.

50. The method as claimed in claim 45, further comprising the steps of providing the first scaffold component comprising a first porous scaffold component having pores of a first size and providing the second scaffold component comprises a second porous scaffold component having pores of a second size, the pores being sized appropriately to hold and deliver the respective growth factors; and viable autologous osteogenic and/or angiogenic cells, which the respective scaffold components hold and deliver.

51. The method as claimed in claim 50 wherein the first scaffold component comprises the first porous structure having the first pore size adapted to hold and deliver to the injured bone site, growth factors for inducing cellular events that initiate healing.

52. The method as claimed in claim 50 wherein the second scaffold component comprises the porous structure having the second pore size adapted to hold and deliver autologous osteogenic and angiogenic cells.

53. The method as claimed in claim 50. wherein the first pore size is relatively small and the second pore size is relatively large whereby the relatively smaller pore size of the first scaffold sponge is adapted for holding and delivering the PRP and growth factors to the bone defect site and the relatively larger pore size of the second scaffold component is adapted for holding and delivering the osteogenic and/or angiogenic cells to the bone defect site.

54. The method as claimed in claim 46, wherein the biomimetic bone generating agent is encapsulated within at least one scaffold component.

55. The method as claimed in claim 44, wherein the autologous osteogenic and angiogenic cells are provided by Bone Marrow Aspirate (BMA) and/or Bone Marrow Aspirate Concentrate (BMAC).

56. The method as claimed in claim 55 wherein the BMA and/or BMAC is collected preoperatively, grown/modified in the lab and used when needed during surgery.

57. The method as claimed in claim 47, wherein the biomimetic bone generating agent is encapsulated within at least one of the first and second scaffold components.

58. The method as claimed in claim 46, further comprising the step of providing the biomimetic bone generating agent between the first scaffold component and the second scaffold component.

59. The method as claimed in claim 57 wherein the biomimetic bone generating agent is provided as a layer between the first scaffold component and the second scaffold component.

60. The method as claimed in claim 44, wherein once the device has been implanted, mechanical fixing means may be used to fix the bone fracture in place if the damaged tissue/bone requires additional surgical intervention/stabilization.

61. The method as claimed in claim 60 wherein the fixing means comprises at least one selected from the following group: secure pins, screws and orthopaedic fixing devices.

62. The method as claimed in claim 44, wherein different sized -TCP/OCP granules may be used to trap air bubbles between the first and second scaffold components to be utilized by the cells as needed.

63. The method as claimed in claim 44, wherein the scaffold component(s) are flushed with oxygen so that oxygen will be trapped within the fibers and can be utilized by the cells when needed.

64. The method as claimed in claim 44 wherein as the scaffold component(s), in the form of a collagen layer, is being manufactured, trapped air bubbles are retained in the scaffold component and these trapped air bubbles can be utilized by the cells if needed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0076] The device of the present invention will now be described more particularly, with reference to the accompanying drawings and to the following Examples, in which are, respectively, shown and described, by way of example only, a number of alternative embodiments of the device and method of the present invention.

[0077] In the drawings:

[0078] FIG. 1 is a schematic diagram showing the requirements for bone regeneration and revascularisation represented by the Diamond Concept;

[0079] FIG. 2 is a schematic longitudinal cross sectional view of a first embodiment of the device of the present invention and more specifically, represents a first stage in the manufacture of a first embodiment of the device of the present invention comprising: A first scaffold component comprising a porous biological material comprising, in this embodiment, collagen, configured to carry and maintain growth factors, for instance, growth factors present in BMA and/or viable platelet rich plasma (PRP);

[0080] A second scaffold component comprising a porous biological material comprising, in this embodiment, collagen, configured to carry and maintain viable osteogenic and angiogenic cells provided by Bone Marrow Aspirate (BMA); and

[0081] A third component comprising a biomimetic bone generating phase, optionally comprising a calcium phase; which also functions as an osteoconductive scaffold for providing a stable mechanical environment. In this embodiment, the biomimetic calcium phase preferably comprises a calcium phosphate compound optionally, in the form of a salt. In this embodiment, the calcium phosphate compound comprises Octacalcium Phosphate (OCP);

[0082] FIG. 3 is a schematic longitudinal cross sectional view of the first embodiment of the device of the present invention shown in FIG. 2, and more specifically, represents a stage in the in-situ use of the first embodiment of the device of the present invention as will be described hereinbelow;

[0083] FIG. 4 is a schematic longitudinal cross sectional view of the first embodiment of the device of the present invention shown in FIG. 2, and more specifically, represents a stage in the in-situ use of the first embodiment of the device of the present invention;

[0084] FIG. 5 is a schematic diagram showing the Figures of the earlier patent application and the related Figures of the present application;

[0085] FIG. 6(a) is the same as shown in FIG. 2 and FIGS. 6(b) and (c) are photos showing alternative views of the device of the first embodiment and showing in particular, the porous nature of each of the biological material scaffolds;

[0086] FIG. 7 is a similar view to that shown in FIGS. 6 (a), (b) and (c);

[0087] FIG. 8 shows in cross section, the porous nature of the respective scaffold sponges, showing in particular, the relatively larger pore size of the second scaffold sponge and the relatively smaller pore size of the first scaffold sponge; the granular nature of the OCP is also shown in FIG. 8;

[0088] FIG. 9 is a further view similar to that shown in FIG. 8;

[0089] FIG. 10 is a schematic diagram showing the manner of use of the device shown in FIGS. 1 to 10;

[0090] FIG. 11 is a cross sectional view of an alternative embodiment of the device of the present invention in which the OCP is encapsulated in the scaffold sponge and are interspersed throughout the collagen layer(s); not dispersed in between the first scaffold sponge and the second scaffold sponge as was the case in the first embodiment shown in FIGS. 1 to 10; as the collagen layers are being cast, the OCP granules will be mixed into the collagen before it solidifies so that the granules are interspersed throughout the collagen layer.

[0091] FIG. 12 is a schematic diagram showing the Figures of the earlier patent application and the Figures of the present application in relation to the second embodiment;

[0092] FIG. 13(a), FIGS. 13(b) and 13(c) are pictorial representations showing alternative views of the device of the alternative embodiment of FIGS. 11 and 12;

[0093] FIG. 14(a), FIG. 14(b) and FIG. 14(c) are pictorial representations of the device of the alternative embodiment of FIGS. 11 to 13 and FIG. 14(c) is a photo of the device as shown in FIGS. 14(a) and 14(b);

[0094] FIG. 15(a), FIG. 15(b) and FIG. 15(c) show the same device and views as shown in FIG. 14(a), FIG. 14(b) and FIG. 14(c);

[0095] FIG. 16 is a schematic diagram of an alternative embodiment where the OCP is encapsulated within a third collagen layer which is sandwiched between the first and second collagen layers; with a porosity to specifically trap the PRP fraction and associated growth factors. The second collagen layer is designed specifically for the BMA/BMAC cells; and

[0096] FIG. 17 is a schematic diagram of a further alternative embodiment comprising a single collagen sponge comprising both the relative large pores (100-350 M) and the relative small pores (2-10 M) and also comprising the OCP encapsulated within one single collagen layer.

DETAILED DESCRIPTION OF THE DRAWINGS

[0097] Referring initially to FIGS. 2 to 10, there is shown a first embodiment of the device of the present invention. The device in this embodiment is indicated generally by the reference numeral 100 and comprising a first porous scaffold component and a second porous scaffold component. The first scaffold component is indicated generally by reference numeral 101 and comprises pores 110 having a relatively small pore size (2-10 M). The second scaffold component 102 comprises pores 120 having a relatively larger pore size (100-350 M).

[0098] This sizing of the pores 110, 120 in the respective first scaffold component 101 and the second scaffold 102 has the advantage that the relatively larger pore size of the second scaffold sponge 102 is adapted for holding and delivering the osteogenic and/or angiogenic cells to the bone defect site; and the relatively smaller pore size of the first scaffold sponge 101 is adapted for holding and delivering the PRP and growth factors to the bone defect site.

[0099] As also shown in FIGS. 2 to 10, a biomimetic bone generation agent, preferably, OCP is provided in between the first scaffold component 101 and the second scaffold component 102. The OCP is preferably in the form of granules 130 as shown in FIG. 2 and corresponding Figures and also shown in FIG. 8b. The granules 130 of OCP are dispersed on the surface of the first scaffold component 101 which in this embodiment is a porous sponge 101 and the second scaffold component 102 which is also a porous sponge 102.

[0100] As shown in FIG. 3, growth factors provided by Plasma-rich platelets (PRP) are included in the first sponge and as shown in FIG. 4, osteogenic and/or angiogenic cells are incorporated in the second scaffold sponge 102.

[0101] Referring now to FIG. 11, there is shown, a second embodiment of the device of the present invention in which the OCP indicated by reference numeral 230 is encapsulated in the scaffold sponge and are interspersed throughout the collagen layer(s); thus, in this second embodiment, the OCP is not dispersed in between the first scaffold sponge and the second scaffold sponge as was the case in the first embodiment shown in FIGS. 1 to 10; as the collagen layers are being cast, the OCP granules 230 will be mixed into the collagen before it solidifies so that the OCP granules 230 are interspersed throughout the collagen layer.

[0102] The device in the second embodiment is indicated generally by the reference numeral 200 and comprising a first porous scaffold component and a second porous scaffold component. The first scaffold component is indicated generally by reference numeral 201 and comprises pores 210 having a relatively small pore size (2-10 M). The second scaffold component 202 comprises pores 220 having a relatively larger pore size (100-350 M).

[0103] This sizing of the pores 210, 220 in the respective first scaffold component 101 and the second scaffold 202 has the advantage that the relatively larger pore size of the second scaffold sponge 202 is adapted for holding and delivering the osteogenic and/or angiogenic cells to the bone defect site; and the relatively smaller pore size of the first scaffold sponge 201 is adapted for holding and delivering the growth factors to the bone defect site.

[0104] Referring now to FIG. 16, an alternative embodiment of the device will be described. The device in this embodiment is indicated generally by the reference numeral 300 and comprising a first porous scaffold component and a second porous scaffold component. The first scaffold component has a relatively small pore size (2-10 M) and the second scaffold component has a relatively larger pore size (100-350 M) and where the OCP, in the form of granules 330, is encapsulated within a third scaffold layer which is sandwiched between the first and second porous scaffold layers; the first porous scaffold component comprising a porosity to specifically trap the PRP fraction and associated growth factors. The second collagen layer 302 is designed specifically for the BMA/BMAC cells.

[0105] Thus the device 300 comprising a first porous scaffold component 301 and a second porous scaffold component 302. The first scaffold component 301 comprises pores 310 having a relatively small pore size (2-10 M). The second scaffold component 302 comprises pores 320 having a relatively larger pore size (100-350 M).

[0106] This sizing of the pores 310, 320 in the respective first scaffold component 301 and the second scaffold 302 has the advantage that the relatively larger pore size of the second scaffold sponge 302 is adapted for holding and delivering the osteogenic and/or angiogenic cells to the bone defect site; and the relatively smaller pore size of the first scaffold sponge 301 is adapted for holding and delivering the growth factors to the bone defect site.

[0107] Referring now to FIG. 17, a further alternative embodiment of the device will be described. The device in this embodiment is indicated generally by the reference numeral 400 and comprising a single scaffold component in the form of a collagen sponge 401 comprising both the relatively large pores 420 (pore size in the range of 100-350 M) and the relatively small pores 410 (pore size in the range of 2-10 M) and also comprising the OCP 430 encapsulated within the single collagen layer.

EXAMPLES

Example 1

[0108] OCP is prepared following a modification of the publication LeGeros (Calcif Tissue Int. 1985 March; 37(2):194-7) in which calcium and phosphate solutions are first prepared and then mixed. Once the precipitate is fully formed, the OCP is filtered and heated to 50 C. to evaporate any remaining liquids. Once dried, the OCP precipitate is passed through standard testing sieves. The granules are separated into 3 groups, including granules with diameters ranging from 53 to 300 m, 300 to 500 m and 500 to 1000 m. These are sterilised by heating at 120 C. for 2 hours. Previous research has shown that this treatment of heating to 120 C. for 2 hours does not affect the physical properties such as the crystalline structure or specific surface are of the OCP granules. It has also been reported that temperatures exceeding 100 C., over time, induce a gradual collapse of the OCP structure due to dehydration.

[0109] The collagen can be cast using either freeze dry or electrospinning techniques. In this Example, Collagen scaffolds will be produced by lyophilisation of a collagen suspension. The suspension will be produced by blending micro fibrillar bovine tendon collagen in 0.05 M acetic acid. The resulting suspension will contain 0.5% w/v of collagen. The suspension will be maintained at 4 C. during blending to prevent denaturation of the collagen. Following blending the suspension will be degassed in a vacuum desiccator for 60 min to remove trapped air bubbles. The Collagen slurry will be lyophilized following a protocol developed by O'Brien et al., to produce Collagen scaffolds with a homogeneous pore structure. Briefly, 67.25 mL of the Collagen suspension will be pipetted into a stainless-steel tray (55 in., grade 304 SS). The tray will be placed onto the freeze-dryer shelf and the freezing cycle will be started. To make the collagen with the larger pore size i.e. 325 Mthe samples will be cooled to a temperature of 20 C at a constant cooling rate of 0.9 C.=min and will be held at this temperature for 20 min to allow the suspension to freeze. The temperature will then be increased to 10 C. to start annealing and will be held there for a specific annealing time which in this case is 0.25 hours. After freeze-drying the scaffolds will be dehydrothermally crosslinked at 105 C. for 24 hours in a vacuum oven at 50 mTorr.

[0110] In one embodiment of the present invention, the collagen is cast with conditions to produce a small pore size (e.g. varying the concentration of acetic acid), freeze dried, and OCP with a granular size of 500 to 1000 M will be addednot in a layer but rather as granules dispersed on top of the set collagen layerand the second collagen layer will be cast on top and freeze dried at different conditions to yield a larger pore size (see above).

[0111] In another embodiment of the inventionthe first collagen layer (smaller pore scaffold) and the second collagen layer (larger pore scaffold) will be cast separately. Again, the OCP granules will be dispersed on top of one of the layers, then using a biological adhesive and/or a synthetic glue, the first and second layers will be glued together.

[0112] In yet another embodiment of this inventionas the collagen layers are being cast, the OCP granules (53-300 M) will be mixed into the collagen before it solidifies so that the granules are interspersed throughout the collagen layers.

[0113] Once the surgeon has the device in the operating theatre, the scaffold can be cut to the required size depending on the therapeutic application. For this example, the collagen scaffolds can be cut into strips of 53 cm.

[0114] Plasma-Rich Platelets (PRP)

[0115] The PRP is obtained from a sample of patients' blood drawn during surgery. PRP is produced by centrifugation of whole blood using the Smartprep2 centrifuge (Harvest Technologies, Munich, Germany). In general, the blood is centrifuged twicethe first spin, separates out the Red blood cells (RBC) while the second centrifugation step concentrates the Platelets in the smallest final plasma volume. An initial starting volume of 30 cc venous blood draw will yield 3-5 cc of PRP.

[0116] This obtained volume of PRP will then be canted over the top of the device allowing a few minutes for the PRP to sediment down through the collagen scaffold and for the scaffold to absorb the PRP and all essential elements e.g. growth factors.

[0117] Bone Marrow Aspirate (BMA)

[0118] In some embodiments of this invention, BMA will be used and in other embodiments of the invention, BMAC will be used. Both techniques are described here.

[0119] A total of 60 ml bone marrow aspirate (BMA) is obtained by vacuum aspiration from the posterior iliac crest. Bone marrow aspiration concentrate (BMAC) is produced via density gradient centrifugation using the Smartprep2 centrifuge (Harvest Technologies, Munich, Germany) in accordance with the manufacturer's directions including 2,500 rpm for 3 min and followed by 2,300 rpm for 9 min to yield a total volume of 8 ml BMAC.

[0120] This volume of BMAC is carefully canted over the top of the already soaked device allowing a few minutes for the BMAC to sediment down through the collagen scaffold and also allowing the scaffold to absorb the BMAC.

[0121] Once the scaffold has absorbed both cell types the surgeon can roll the strip into a roll as shown schematically, in FIG. 10 and using the AVN system the device of the present invention can be implanted into the femoral head. Several strips/rolls can be used to fill the bone void.

Example 2

[0122] Again, OCP will be prepared following a modification of the publication LeGeros (Calcif Tissue Int. 1985 March; 37(2):194-7) in which calcium and phosphate solutions are first prepared and then mixed. Once the precipitate is formed, the OCP is filtered and heated to 50 C. to evaporate any remaining liquids. Once dried, the OCP precipitate is passed through standard testing sieves. Granules are separated into 3 groups, granules with diameters ranging from 53 to 300 m, 300 to 500 m and 500 to 1000 m. These will be sterilised by heating at 120 C. for 2 hours. Previous research has shown that this treatment of heating to 120 C. for 2 hours does not affect the physical properties such as the crystalline structure or specific surface are of the OCP granules. It has also been reported that temperatures exceeding 100 C., over time induce a gradual collapse of the OCP structure due to dehydration.

[0123] In this embodiment of the Invention, Spinplant in Germany which can produce collagen Nano fibres will design two collagen weaves specifically designed to trap either BMA/BMAC or PRPs depending on their pore sizes. As with Example 1, the smaller PRP cells will be initially canted onto the device in surgery followed by the larger BMAC, allowing time for them to sediment through the collagen scaffold. The scaffolds designed by Spinplant will be optimized to best facilitate cellular growth within the scaffold and to best house the proteins contained within the PRP.

[0124] Once the surgeon has the device in the operating theatre, the scaffold can be cut to the required size depending on the therapeutic application. For this example, the collagen scaffolds can be cut into strips of 53 cm.

[0125] Plasma-Rich Platelets (PRP)

[0126] The PRP is obtained from a sample of patients' blood drawn during surgery. PRP is produced by centrifugation of whole blood using the Smartprep2 centrifuge (Harvest Technologies, Munich, Germany). In general, the blood is centrifuged twicethe first spin, separates out the Red blood cells (RBC) while the second centrifugation step concentrates the Platelets in the smallest final plasma volume. An initial starting volume of 30 cc venous blood draw will yield 3-5 cc of PRP.

[0127] This obtained volume of PRP will then be canted over the top of the device allowing a few minutes for the PRP to sediment down through the collagen scaffold and for the scaffold to absorb the PRP and all essential elements e.g. growth factors.

[0128] Bone Marrow Aspirate

[0129] In some embodiments of this invention, BMA is used and in other embodiments of the invention, BMAC are used. Both techniques are described here.

[0130] A total of 60 ml bone marrow aspirate (BMA) is obtained by vacuum aspiration from the posterior iliac crest. Bone marrow aspiration concentrate (BMAC) is produced via density gradient centrifugation using the Smartprep2 centrifuge (Harvest Technologies, Munich, Germany) in accordance with the manufacturer's directions including 2,500 rpm for 3 min and followed by 2,300 rpm for 9 min to yield a total volume of 8 ml BMAC.

[0131] This volume of BMAC is carefully canted over the top of the already soaked device allowing a few minutes for the BMAC to sediment down through the collagen scaffold and also allowing the scaffold to absorb the BMAC.

[0132] Once the scaffold has absorbed both cell types, the surgeon can roll the strip into a roll and, using the AVN system, the device of the present invention can be implanted into the femoral head. Several strips/rolls can be used to fill the bone void.

[0133] In some embodiments, the BMA/BMAC may be collected preoperatively, grown/modified in the lab and used when neededduring surgery. This changes the categorisation of the invention from a medical device to a medicine.

[0134] In some embodiments, the damaged tissue/bone may require surgical intervention/stabilisation in addition to the materials added to address the bone defect and aid in the bone regeneration. For example, in some embodiments once the device has been implanted, secure pins, screws and other orthopaedic devices can be used to fix the bone fracture in place.

[0135] In some embodiments, different sized -TCP/OCP granules may be used to trap air bubbles between the two sheets of collagen to be utilised by the cells as needed.

[0136] In some embodiments, the collagen sheets will be flushed with oxygen so that oxygen will be trapped within the fibres and can be utilised by the cells when needed.

[0137] In some embodiments as the collagen layer is being made the step to remove trapped air bubbles specifically degassing in a vacuum desiccator for 60 min will be eliminated. These trapped air bubbles can be utilised by the cells if needed.

[0138] The words comprises/comprising when used in this specification are to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0139] The examples and other embodiments contained here are only exemplary in nature. They and are not intended to be limiting in describing the full scope of compositions and methods of this invention as defined in the appended Claims.