Methods, materials, and apparatus for treating bone and other tissue

• US 20070027230A1
• Filed: 02/22/2006
• Published: 02/01/2007
• Est. Priority Date: 03/21/2004
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: Disc-O-Tech Medical Technologies Limited (Medtronic Plc)
• Inventors: Beyar, Mordechay, Globerman, Oren, Wachsler-Avrahami, Hila, Shavit, Ronen
• Granted Patent: US 8,415,407 B2
• Time in Patent Office: Days
• US Class Current: 523/117
• CPC Class Codes: A61B 17/1604 Chisels; Rongeurs; Punches; Stamps
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/3421 Cannulas
• CPC Class Codes: A61B 17/8811 characterised by the introducer tip, i.e. the part inserted into or onto the bone
• CPC Class Codes: A61B 17/8816 characterised by the conduit, e.g. tube, along which fluid flows into the body or by conduit connections
• CPC Class Codes: A61B 17/8822 characterised by means facilitating expulsion of fluid from the introducer, e.g. a screw pump plunger, hydraulic force transmissions, application of vibrations or a vacuum
• CPC Class Codes: A61B 17/8836 for heating, cooling or curing of bone cement or fluid fillers
• CPC Class Codes: A61B 2017/00539 hydraulically
• CPC Class Codes: A61B 2017/2905 flexible
• CPC Class Codes: A61B 2090/3937 Visible markers
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• 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 2002/4693 hydraulic
• CPC Class Codes: A61L 24/043 Mixtures of macromolecular materials
• CPC Class Codes: A61L 24/06 obtained by reactions only involving carbon-to-carbon unsaturated bonds A61L24/043, A61L24/046 take precedence
• CPC Class Codes: A61L 2430/02 for reconstruction of bones; weight-bearing implants
• CPC Class Codes: A61L 2430/38 for reconstruction of the spine, vertebrae or intervertebral discs
• CPC Class Codes: A61L 27/26 Mixtures of macromolecular compounds
• CPC Class Codes: B01F 27/95 with stirrers having planetary motion, i.e. rotating about their own axis and about a sun axis
• CPC Class Codes: B01F 35/3202 Hand driven
• CPC Class Codes: B01F 35/53 : characterised by the configuration of the interior, e.g. baffles for facilitating the mixing of components
• CPC Class Codes: B01F 35/75425 : using pistons or plungers
• CPC Class Codes: B01F 35/754251 : reciprocating in the mixing receptacle
• CPC Class Codes: C08L 33/12 : Homopolymers or copolymers of methyl methacrylate

Abstract

A bone cement comprising a first component and a second component, wherein contacting the first component and the second component produces a mixture which attains a high viscosity an initial period and the viscosity of the mixture remains relatively stable for a working time of at least 5 minutes after the initial setting period, and the mixture is suitable for in-vivo use.

Claims

11. A bone cement comprising:

a first component; and

a second component,

wherein, contacting the first component and the second component produces a mixture which attains a viscosity greater than 200 Pascal seconds within 1 minute,

wherein the viscosity of the mixture remains between 200 and 2000 Pascal seconds for a working time of at least 5 minutes after the initial period,

wherein the viscosity of said cement is changing by less than 10% in a period of 2 minutes within said working time, and

wherein the mixture is suitable for in-vivo use.

12. A bone cement comprising:

a mixture resulting from the contacting of a first component including PMMA with a second component including MMA,

wherein a porton of the PMMA has a molecular weight between about 600,000 Dalton and about 1,200,000 Dalton.

13. The bone cement of claim 12, wherein the first component contains about 69.4% w/w PMMA, about 30.1% Barium Sulfate, and about 0.5% Benzoyl Peroxide;

and wherein the second component contains about 98.5% v/v MMA, about 1.5% DMPT, and about 20 ppm Hydroquinone.

14. The bone cement of claim 12, wherein the average molecular weight of the PMMA is between about 80,000 Dalton and about 180,000 Dalton.

15. The bone cement of claim 12, wherein the average molecular weight of the PMMA is about 110,000 Dalton.

16. The bone cement of claim 12, wherein at least 80% of the PMMA has a bead size between 10 and 200 microns.

17. The bone cement of claim 12, further comprising processed bone and/or synthetic bone that is mixed together with the first component and the second component.

18. A bone cement kit comprising:

a first component including PMMA and a second component including MMA,

wherein a portion of the PMMA has a molecular weight between about 600,000 Dalton and about 1,200,000 Dalton.

19. The bone cement kit of claim 18, wherein the first component includes about 69.4% w/w PMMA, about 30.1% Barium Sulfate, and about 0.5% Benzoyl Peroxide;

and

the second component including about 98.5% v/v MMA, about 1.5% DMPT, and about 20 ppm Hydroquinone.

20. The bone cement kit of claim 18, wherein the average molecular weight of the PMMA is between about 80,000 Dalton and about 180,000 Dalton.

21. The bone cement kit of claim 18, wherein the average molecular weight of the PMMA is about 110,000 Dalton.

22. The bone cement kit of claim 18, wherein at least 80% of the PMMA has a bead size between 10 and 200 microns.

23. A cement comprising an acrylic polymer mixture, the cement achieving a viscosity of at least 500 Pascal-second within 180 seconds following initiation of mixing of a monomer component and a polymer component and characterized by sufficient biocompatability to permit injection into bone.

24. A bone cement comprising an acrylic polymer mixture, the cement achieving a viscosity of at least 500 Pascal-second when 100% of a polymer component is wetted by a monomer component.

25. A bone cement according to claim 24, the cement achieving a viscosity of at least 500 Pascal-second when 95% of a polymer component is wetted by a monomer component.

26. A bone cement comprising:

a monomer containing component and a polymer containing component, the cement characterized in that when the monomer containing component and the polymer containing component contact one another so that the polymer component is wetted by the monomer component a high viscosity cement characterized by a relatively stable flowability for a period of at least 8 minutes results after an intitial setting period.

27. A bone cement according to claim 26, wherein the initial period does not exceed 2 minutes.

28. A bone cement according to claim 26, wherein the initial period does not exceed 0.5 minutes.

29. A bone cement according to claim 26, wherein the initial period does not exceed 5 seconds.

30. A bone cement according to claim 26, wherein the high viscosity is at least 500 Pascal sec.

31. A bone cement according to claim 26, wherein the high viscosity is at least 900 Pascal sec.

32. A bone cement according to claim 26, wherein the stable flowability results from a change in viscosity of less than 200 Pascal sec.

33. A bone cement comprising a monomer containing a monomer component and a polymer containing component, the cement characterized in that when the monomer containing component and the polymer containing component contact one another so that the polymer component is wetted by the monomer component a high viscosity cement is formed after an initial period, a viscosity of said high viscosity cement changing by less than 20% in a period of 5 minutes.

34. A bone cement according to claim 33, wherein the initial period does not exceed 2 minutes.

35. A bone cement according to claim 33, wherein the initial period does not exceed 0.5 minutes.

36. A bone cement according to claim 33, wherein the initial period does not exceed 5 seconds.

37. A bone cement according to claim 33, wherein the high viscosity is at least 500 Pascal sec.

38. A bone cement according to claim 33, wherein the high viscosity is at least 900 Pascal sec.

39. A bone cement according to claim 33, wherein the stable flowability results from a change in viscosity of less than 200 Pascal sec.

40. A bone cement comprising an acrylic polymer mixture, the cement achieving a viscosity of at least 500 Pascal-second within 180 seconds following initial contact of a monomer component and a polymer component.

1. A bone cement comprising:

a first component; and

a second component,

wherein, contacting the first component and the second component produces a mixture which attains a viscosity greater than 500 Pascal seconds within an initial period,

wherein the viscosity of the mixture remains between 500 and 2000 Pascal seconds for a working time of at least 5 minutes after the initial period, and

wherein the mixture is suitable for in-vivo use.

2. The bone cement of claim 1, wherein the working time is at least 8 minutes long.

3. The bone cement of claim 1, wherein the initial period is less than 3 minutes

4. The bone cement of claim 1, wherein the initial period does not exceed 1 minute.

5. The bone cement of claim 1, wherein the mixture solidifies after the working time.

6. The bone cement of claim 1, wherein the initial period is less than 3 minutes and the mixture solidifies after the working time

7. The bone cement of claim 6, wherein the first component includes PMMA and Barium Sulfate.

8. The bone cement of claim 6, wherein the second component includes MMA and DMPT.

9. The bone cement of claim 6, wherein the first component includes PMMA, Barium Sulfate, and Benzoyl Peroxide, and wherein the second component includes MMA, DMPT, and Hydroquinone.

10. The bone cement of claim 1, wherein the viscosity of greater than 500 Pascal-second results at least partly from a polymerization reaction.

41. A bone cement according to claim 40, wherein the viscosity is at least 900 Pascal sec.

42. A bone cement according to claim 40, wherein the viscosity is at least 1500 Pascal sec.

43. A bone cement according to claim 40, wherein the viscosity is achieved within 2 minutes.

44. A bone cement according to claim 40, wherein the viscosity is achieved within 1 minute.

44-1. A bone cement according to claim 40, wherein the viscosity is achieved within 45 seconds.

46. A bone cement, the cement achieving a putty like state when 95% of a polymer component is wetted by a monomer component.

47. A bone cement according to claim 46, wherein the putty like state is characterized by a viscosity of at least 500 Pascal sec.

48. A bone cement according to claim 46, wherein the putty like state is characterized by a viscosity of at least 900 Pascal sec.

49. A bone cement according to claim 46, wherein the 95% wetting occurs within 60 seconds of an initial contact.

50. A method of injecting bone cement, the method comprising:

(a) retaining a cement characterized by a viscosity of at least 500 Pascal-second within a reservoir; and

(b) applying sufficient pressure to the cement in the reservoir to propel at least 5 ml of the material from the reservoir through a bone injection cannula operably connected to an outlet of the reservoir and having a distal tip inserted in a bone, the cannula characterized by an internal diameter not exceeding 4 mm.

51. A bone cement comprising:

a polymer component; and

a monomer component,

wherein, when the two components are mixed together, the resulting mixture attains, within a period of up to 2 minutes, a putty-like consistency

wherein the viscosity of the resulting mixture remains approximately constant during a period of time of at least 8 minutes.