POLYMER CEMENT FOR PERCUTANEOUS VERTEBROPLASTY AND METHODS OF USING AND MAKING SAME

• US 20080044374A1
• Filed: 06/04/2007
• Published: 02/21/2008
• Est. Priority Date: 05/14/2004
• Status: Active Grant

• Current Assignee: Teknimed SA
• Original Assignee: Teknimed SA
• Inventors: Leonard, Alain, Lavergne, Claudine
• Granted Patent: US 8,153,704 B2
• Time in Patent Office: Days
• US Class Current: 424/78.31
• CPC Class Codes: A61L 24/0094 containing macromolecular fillers
• CPC Class Codes: A61L 2430/02 for reconstruction of bones; weight-bearing implants
• CPC Class Codes: A61L 27/446 with other specific inorganic fillers other than those covered by A61L27/443 or A61L27/46
• CPC Class Codes: C08L 33/12 Homopolymers or copolymers of methyl methacrylate

Abstract

The invention provides a fluid cement for medical use for bone reconstruction, in particular for filling the vertebral body, and a binary composition which is intended for the preparation of such a cement. The invention also provides a device for conditioning the binary composition, and a method of preparing a bone cement from a binary composition. The fluid cement according to the invention comprises: a) approximately 60% to 85% by weight of a polymer comprising a polymethylmethacrylate and a methylmethacrylate monomer and b) approximately from 15 to 40% by weight of a radio-opaque composition. Preferably, the radio-opaque composition comprises a radio-opacifier, such as barium sulfate and zirconium dioxide, in a mixture with a calcium phosphate, for example apatite hydroxide.

Claims

1. Fluid cement, for medical use, for filling the vertebral body, characterized in that it comprises:

a) approximately 60% to 85% by weight of a polymer comprising a polymethylmethacrylate and a methylmethacrylate monomer, and b) approximately from 15% to 40% by weight of a radio-opaque composition.

2. The fluid cement according to claim 1, characterized in that said radio-opaque composition comprises a radio-opaque compound and calcium phosphate.

3. The fluid cement according to claim 2, characterized in that said radio-opaque composition comprises a radio-opaque compound and calcium phosphate wherein the radio-opaque compound comprises approximately 18% to 37% by weight of the fluid cement and the calcium phosphate comprises approximately 3% to 10% by weight of the fluid cement.

4. The fluid cement of claim 3, wherein the radio-opaque compound comprises about 27% by weight of the fluid cement.

5. The fluid cement of claim 3, wherein the radio-opaque compound comprises about 34% by weight of the fluid cement.

6. The fluid cement of claim 3, wherein the radio-opaque compound comprises about 20% by weight of the fluid cement.

7. The fluid cement of claim 3, wherein the calcium phosphate comprises about 3% by weight of the fluid cement.

8. The fluid cement of claim 3, wherein the calcium phosphate comprises about 4% by weight of the fluid cement.

9. The fluid cement of claim 3, wherein the calcium phosphate comprises about 6% by weight of the fluid cement.

10. The fluid cement according to claim 2, characterized in that said radio-opaque compound is selected from the group consisting of barium sulfate and zirconium dioxide.

11. The fluid cement according to claim 2, characterized in that the calcium phosphate is apatite hydroxide.

12. The fluid cement according to claim 1, characterized in that the polymethylmethacrylate and the methylmethacrylate monomer are introduced in a weight ratio between 1 and 2.

14. The fluid cement according to claim 1, characterized in that it comprises in addition an effective quantity of one or more of the reagents selected from the group consisting of a chemical polymerization activator, a polymerization initiator and a stabilizer.

15. The fluid cement according to claim 14, wherein the chemical polymerization activator is dimethylparatoluidine.

16. The fluid cement according to claim 14, wherein the polymerization initiator is benzoyl peroxide.

17. The fluid cement according to claim 14, wherein the stabilizer is hydroquinone.

18. A binary composition intended for preparation of a bone cement according to claim 1, composed of a liquid component L comprising a methylmethacrylate monomer and a powder component P comprising a polymethylmethacrylate, characterized in that the powder component P comprises approximately from 25% to 60% by weight relative to the weight of powder of a radio-opaque composition.

19. The binary composition according to claim 18, characterized in that the powder component P comprises between approximately 35% and 50% by weight relative to the weight of powder of a radio-opaque composition.

20. The binary composition according to claim 18, characterized in that the radio-opaque composition comprises a radio-opaque compound and calcium phosphate.

21. The binary composition according to claim 20, characterized in that the radio-opaque composition comprises a radio-opaque compound and calcium phosphate wherein the radio-opaque compound comprises approximately 25% to 50% by weight of the powder component and wherein the calcium phosphate comprises approximately 4% to 12% by weight of the powder component.

22. The binary composition according to claim 21, wherein the radio-opaque compound comprises about 45% by weight of the powder component.

23. The binary composition according to claim 21, wherein the radio-opaque compound comprises about 27% by weight of the powder component.

24. The binary composition according to claim 21, wherein the calcium phosphate comprises about 5% by weight of the powder component.

25. The binary composition according to claim 21, wherein the calcium phosphate comprises about 9% by weight of the powder component.

26. The binary composition according to claim 20, characterized in that said radio-opaque compound is selected from the group consisting of barium sulfate and zirconium dioxide.

27. The binary composition according to claim 20, characterized in that the calcium phosphate is apatite hydroxide.

28. The binary composition according to claim 18, comprising in addition an effective quantity of one or more of the reagents selected from the group consisting of:

a chemical polymerization activator in the liquid component L, a polymerization initiator in the powder component P, and a stabilizer.

29. The binary composition according to claim 28, wherein the chemical polymerization activator is dimethylparatoluidine.

30. The binary composition according to claim 28, wherein the polymerization initiator is benzoyl peroxide.

31. The binary composition according to claim 28, wherein the stabilizer is hydroquinone.

32. The binary composition according to claim 18, characterized in that the powder component P and the liquid component L are in a weight ratio P/L between 1 and 2.

33. The binary composition according to claim 32, characterized in that the powder component P and the liquid component L are in a weight ratio P/L between 1.4 and 1.6.

34. A device intended for preparation of a fluid cement for medical use from a binary composition according to claim 18, characterized in that it comprises:

i) a first receptacle containing the liquid component L, and ii) a second receptacle containing the powder component P.

35. A method of preparing a fluid cement, for medical use, for filling the vertebral body, comprising essentially the step consisting in mixing the components made of powder P and liquid L according to claim 18 into a homogeneous mass.

36. The method according to claim 35, in which the powder component P and the liquid component L are provided in a weight ratio P/L between 1 and 2.

37. The method according to claim 36, in which the powder component P and the liquid component L are provided in a weight ratio P/L between 1 and 2, preferably between 1.4 and 1.6.

38. Fluid cement for medical use for filling the vertebral body prepared by means of the device according to claim 34.

39. Fluid cement for medical use for filling the vertebral body obtained by the method according to claim 35.

13. The fluid cement according to claim 13, characterized in that the polymethylmethacrylate and the methylmethacrylate monomer are introduced in a weight ratio between 1.4 and 1.6.