MOLD APPARATUS AND KIT FOR IN SITU TISSUE REPAIR

• US 20010004710A1
• Filed: 11/18/1998
• Published: 06/21/2001
• Est. Priority Date: 05/06/1994
• Status: Active Grant

• Current Assignee: Disc Dynamics, Inc.
• Original Assignee: Disc Dynamics, Inc.
• Inventors: ARSENYEV, ALEXANDER, RYDELL, MARK A., FELT, JEFFREY C., ZDRAHALA, RICHARD J.
• Granted Patent: US 6,443,988 B2
• Time in Patent Office: Days
• US Class Current: 623/17.12
• CPC Class Codes: A61B 1/00165 with light-conductive means, e.g. fibre optics A61B1/07 takes precedence
• CPC Class Codes: A61B 17/00234 for minimally invasive surgery A61B17/0218, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• CPC Class Codes: A61B 17/16 Bone cutting, breaking or removal means other than saws, e.g. Osteoclasts; Drills or chisels for bones; Trepans arthroscopic bone cutters A61B17/320016; dental implant drills potentially for other surgical use A61C8/0089; bone grinders A61F2/4644, A22C17/06; A61B17/1662 takes precedence over all other subgroups except A61B17/17
• CPC Class Codes: A61B 17/17 Guides or aligning means for drills , mills, pins or wires
• CPC Class Codes: A61B 17/7097 Stabilisers comprising fluid filler in an implant, e.g. balloon; devices for inserting or filling such implants disc prostheses made of inflatable chambers or pockets filled with fluid A61F2/441; replacing the nucleus pulposus A61F2002/444
• CPC Class Codes: A61B 2017/00535 pneumatically or hydraulically operated A61B2017/22051, A61B2090/401 take precedence
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/30756 Cartilage endoprostheses A61F2/3603 takes precedence
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/3099 for temporo-mandibular [TM, TMJ] joints endoprostheses for mandibular reconstruction A61F2/2803
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2/4081 Glenoid components, e.g. cups
• CPC Class Codes: A61F 2/4202 for ankles
• CPC Class Codes: A61F 2/441 made of inflatable pockets or chambers filled with fluid, e.g. with hydrogel
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2/4601 for introducing bone substitute, for implanting bone graft implants or for compacting them in the bone cavity
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/945 : hardenable, e.g. stents formed in situ
• CPC Class Codes: A61F 2002/30016 : differing in hardness, e.g. Vickers, Shore, Brinell
• CPC Class Codes: A61F 2002/30024 : differing in coefficient of friction
• CPC Class Codes: A61F 2002/3008 : radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2002/30235 : tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30563 : having elastic means or damping means, different from springs, e.g. including an elastomeric core or shock absorbers
• CPC Class Codes: A61F 2002/30578 : having apertures, e.g. for receiving fixation screws
• CPC Class Codes: A61F 2002/30583 : filled with hardenable fluid, e.g. curable in-situ
• CPC Class Codes: A61F 2002/30601 : telescopic
• CPC Class Codes: A61F 2002/30841 : Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30929 : having at least two superposed coatings
• CPC Class Codes: A61F 2002/30957 : using a positive or a negative model, e.g. moulds
• CPC Class Codes: A61F 2002/4233 : for metatarso-phalangeal joints, i.e. MTP joints
• CPC Class Codes: A61F 2002/444 : for replacing the nucleus pulposus
• CPC Class Codes: A61F 2002/4627 : with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2002/4635 : using minimally invasive surgery
• CPC Class Codes: A61F 2210/0085 : hardenable in situ, e.g. epoxy resins
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2250/0019 : differing in hardness, e.g. Vickers, Shore, Brinell
• CPC Class Codes: A61F 2250/0021 : differing in coefficient of friction
• CPC Class Codes: A61F 2250/0098 : radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61L 2430/38 : for reconstruction of the spine, vertebrae or intervertebral discs
• CPC Class Codes: A61L 27/18 : obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 29/041 : obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 29/06 : obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: B01F 2101/2305 : Mixers of the two-component package type, i.e. where at least two components are separately stored, and are mixed in the moment of application
• CPC Class Codes: C08G 18/10 : Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• CPC Class Codes: C08G 18/3206 : aliphatic
• CPC Class Codes: C08G 18/4854 : Polyethers containing oxyalkylene groups having four carbon atoms in the alkylene group
• CPC Class Codes: C08G 18/69 : Polymers of conjugated dienes hydrogenated polymers of conjugated dienes C08G18/6208
• CPC Class Codes: C08L 23/00 : Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 67/02 : Polyesters derived from dicarboxylic acids and dihydroxy compounds C08L67/06 takes precedence
• CPC Class Codes: C08L 75/04 : Polyurethanes
• CPC Class Codes: C08L 83/04 : Polysiloxanes
• CPC Class Codes: Y10S 606/907 : Composed of particular material or coated
• CPC Class Codes: Y10S 606/91 : Polymer

Abstract

A method, and related composition and apparatus for repairing a tissue site. The method involves the use of a curable polyurethane biomaterial composition having a plurality of parts adapted to be mixed at the time of use in order to provide a flowable composition and to initiate cure. The flowable composition can be delivered using minimally invasive means to a tissue site and there fully cured provide a permanent and biocompatible prosthesis for repair of the tissue site. Further provided are a mold apparatus, e.g., in the form of a balloon or tubular cavity, for receiving a biomaterial composition, and a method for delivering and filling the mold apparatus with a curable composition in situ to provide a prosthesis for tissue repair.

Claims

1. A method for repairing a tissue site, the method comprising the steps of:

(a) providing a curable polyurethane biomaterial composition comprising a plurality of parts adapted to be mixed at the time of use in order to provide a flowable composition and to initiate cure,

(b) mixing the composition parts in order to initiate cure and employing minimally invasive means to deliver a quantity of the curing composition to the tissue site, and

(c) completely curing the delivered composition to provide a permanent repair of the tissue site.

2. A method according to

claim 1

wherein the composition parts comprise:

(1) a quasi-prepolymer component comprising the reaction product of one or more polyether polyols, one or more isocyanates, and one or more reactive hydrophobic additives, and (2) a curative component comprising one or more polyether polyols, one or more chain extenders, and one or more catalysts,

wherein the composition is sufficiently flowable to permit it to be delivered to the tissue site by minimally invasive means and there undergo complete cure in situ under physiologically acceptable conditions in order to provide a biocompatible material.

3. A method according to

claim 2

wherein the composition provides improved cure characteristics and cured properties as compared to a comparable composition lacking the reactive hydrophobic additive component.

4. A method according to

claim 3

wherein the improved cure characteristics include a significant reduction in the appearance of bubbles when cured in the presence of moisture.

5. A method according to

claim 1

wherein the curing composition provides an induction period of about thirty seconds to two minutes and a set time of about 3 minutes to about 15 minutes following mixing.

6. A method according to

claim 1

wherein the method is used to repair an orthopedic joint selected from the group consisting of diarthroidal and amphiarthroidal joints.

7. A method according to

claim 6

wherein the amphiarthroidal joints are selected from the group consisting of synphysoidal joints and syndemoidal joints.

8. A method according to

claim 7

wherein the synphysiodal joints are intervertebral joints.

9. A method according to

claim 6

wherein the method is performed using endoscopic/arthroscopic surgical instrumentation and under fiberoptic visualization.

10. A method according to

claim 9

wherein the instrumentation comprises a static mixer and delivery cannula to mix and deliver the composition.

21. A method according to

claim 1

, wherein the method comprises the further steps of:

a) providing an implantable mold apparatus comprising an expandable cavity adapted to receive and contain the flowable biomaterial composition and a conduit adapted to connect the cavity to a source of curable, flowable biomaterial composition,

b) inserting the mold apparatus to the tissue site,

c) mixing and delivering biomaterial composition to the mold in order to fill the cavity to a desired extent,

d) permitting the biomaterial composition to completely cure, and

e) employing the molded biomaterial in situ as a prosthesis at the tissue site.

22. A method according to

claim 21

wherein the steps of inserting the mold apparatus, delivering the biomaterial composition, and curing the composition are each performed by minimally invasive means.

23. A method according to

claim 21

wherein the cavity is provided in the form of an inflatable balloon and the method is used to prepare an intact prosthesis.

24. A method according to

claim 23

wherein the method is used to repair an intervertebral disc.

25. A method according to

claim 23

wherein the method is used to resurface a knee.

26. A method according to

claim 21

wherein the cavity is provided in tubular form and the method is used to prepare a tubular implant.

27. A method according to

claim 26

wherein the tubular implant is used to form an implant selected from the group consisting of stents, shunts and grafts.

28. A method according to

claim 27

wherein the tubular implant comprises a prosthetic implant for repairing an abdominal aortic aneurysm.

29. A method according to

claim 21

wherein the composition parts comprise:

(1) a quasi-prepolymer component comprising the reaction product of one or more polyether polyols, one or more isocyanates, and one or more reactive hydrophobic additives, and (2) a curative component comprising one or more polyether polyols, one or more chain extenders, one or more catalysts, wherein the composition is sufficiently flowable to permit it to be delivered to the tissue site by minimally invasive means and there undergo complete cure in situ under physiologically acceptable conditions in order to provide a biocompatible material.

30. A method according to

claim 29

wherein the curing composition provides an induction period of about thirty seconds to two minutes and a set time of about 3 minutes to about 15 minutes following mixing.

11. A curable polyurethane composition comprising a plurality of parts capable of being mixed at the time of use in order to provide a flowable composition and to initiate cure, the parts comprising:

(1) a quasi-prepolymer component comprising the reaction product of one or more polyether polyols, one or more isocyanates, and one or more reactive hydrophobic additives, and (2) a curative component comprising one or more polyether polyols, one or more chain extenders, and one or more catalysts,

wherein the composition is sufficiently flowable to permit it to be delivered to a tissue site by minimally invasive means and there undergo complete cure in situ under physiologically acceptable conditions in order to provide a biocompatible material.

12. A composition according to

claim 11

wherein the composition provides improved cure characteristics and cured properties as compared to a comparable composition lacking the reactive hydrophobic additive.

13. A composition according to

claim 12

wherein the hydrophobic polymer additive is present at a concentration of between about 1% and about 50% by weight, and is selected from the group consisting of hydroxyl- or amine-terminated compounds selected from the group consisting of poybutadiene, polyisoprene, polyisobutylene, silicones, polyethylenepropylenediene, copolymers of butadiene with acryolnitrile, copolymers of butadiene with styrene, copolymers of isoprene with acrylonitrile, copolymers of isoprene with styrene, and mixtures thereof.

14. A composition according to

claim 12

wherein the improved cure characteristics include a significant reduction in the appearance of bubbles when cured in the presence of moisture.

15. A composition according to

claim 11

wherein the curing composition provides an induction period of about thirty seconds to two minutes and a set time of about 3 minutes to about 15 minutes following mixing.

16. A composition according to

claim 12

wherein the improved cured properties include a hardness of about 60 Shore to about 95 Shore, and a tensile strength (measured in the dry stage) of between about 6,000 psi and about 10,000 psi.

17. A composition according to

claim 13

wherein, within the prepolymer, the polyether component is present at a concentration of between about 2% and about 10%, by weight, based on the weight of the composition, and is selected from the group consisting of linear or branched polyols with polyether backbones of polyoxyethylene, polyoxypropylene, and polytetramethylene oxide (polyoxytetramethylene), and copolymers thereof.

18. A composition according to

claim 17

wherein the polyol comprises one or more polytetramethylene oxides having molecular weights in the range of 250 to 2900.

19. A composition according to

claim 13

wherein the isocyanate is present in excess in the prepolymer component and comprises an aromatic (poly)isocyanate selected from the group consisting of 2,2′

- , 2,4′

-, and 4,4′

-diphenylmethanediisocyanate (MDI), and combinations thereof.

20. A kit comprising a plurality of compositions according to

claim 11

, the compositions providing different hardnesses in their cured form, for use in preparing a heterogeneous implant.

31. A mold apparatus for forming a prosthesis in situ, the apparatus comprising an implantable, expandable cavity adapted to receive and contain a flowable, curable biomaterial, and a removable conduit adapted to connect the cavity to a source of flowable biomaterial.

32. An apparatus according to

claim 31

, wherein the apparatus is adapted for use by minimally invasive means and the cavity is a provided in the form of an inflatable balloon for use in preparing an intact prosthesis.

33. An apparatus according to

claim 32

wherein the balloon is adapted for use in repairing an intervertebral disc.

34. An apparatus according to

claim 33

wherein the apparatus further comprises an air passageway positioned to vent the balloon in the course of filling with biomaterial.

35. An apparatus according to

claim 33

further comprising distal control valves for the biomaterial conduit and air passageway, respectively.

36. An apparatus according to

claim 32

wherein the balloon provides a knee prosthesis and is adapted to be permanently positioned and filled in apposition to subchondral bone.

37. An apparatus according to

claim 36

wherein the balloon comprises a surface for contact with subchondral bone, the surface being provided with one or more foot pads adapted to be implanted into corresponding anchor points drilled within subchondral bone.

38. An apparatus according to

claim 36

wherein the balloon comprises a surface for contact with subchondral bone, the surface being fenestrated in order to permit the passage of biomaterial from the cavity to contact with the subchondral bone.

39. A surgical kit comprising an apparatus according to

claim 37

in combination with a template for use in drilling anchor points in subchondral bone at positions corresponding to those of foot pads on the apparatus.

40. A surgical kit for use in preparing a prosthesis in vivo, the kit comprising (a) an implantable mold apparatus comprising an expandable cavity adapted to receive and contain a flowable, curable biomaterial, and a removable conduit adapted to connect the cavity to a source of curable, flowable biomaterial and (b) a supply of a curable, flowable polyurethane biomaterial composition.

41. A prosthesis for repairing an intervertebral disc, the prosthesis comprising an expanded mold cavity containing a cured, biocompatible, polyurethane biomaterial composition, the prosthesis providing a hardness of about 60 Shore to about 95 Shore, and a tensile strength (measured in the dry stage) of between about 6,000 psi and about 10,000 psi.

42. A prosthesis for repairing the surface of a knee joint, the prosthesis comprising a cured, biocompatible, polyurethane biomaterial composition providing a hardness of about 60 Shore to about 95 Shore, and a tensile strength (measured in the dry stage) of between about 6,000 psi and about 10,000 psi.

43. A prosthesis according to

claim 42

wherein the prosthesis is heterogeneous, comprising a plurality of cured polyurethane compositions, in order to provide layers having one or more different properties.

44. A prosthesis according to

claim 42

wherein the cured biomaterial is provided within a mold cavity and the prosthesis is adapted to be permanently positioned in apposition to subchondral bone.

45. A prosthesis according to

claim 43

wherein the mold cavity is provided in the form of a balloon comprising a surface for contact with subchondral bone, the surface being provided with one or more foot pads adapted to be implanted into corresponding anchor points drilled within subchondral bone.