Formulation for a cement preparation as bone substitute

• US 20050287071A1
• Filed: 05/31/2005
• Published: 12/29/2005
• Est. Priority Date: 12/03/2002
• Status: Abandoned Application

• Current Assignee: Kyphon SARL (Medtronic Plc)
• Original Assignee: Kyphon Incorporated
• Inventors: Wenz, Robert
• Application Number:
  US11/141,769
• Publication Number:
  US 20050287071A1
• Time in Patent Office: Days
• US Class Current: 424/9.4
• CPC Class Codes: A61K 2300/00 Mixtures or combinations of active ingredients, wherein at least one active ingredient is fully defined in groups A61K31/00 - A61K41/00
• CPC Class Codes: A61K 33/42 Phosphorus; Compounds thereof
• CPC Class Codes: A61K 49/0409 Physical forms of mixtures of two different X-ray contrast-enhancing agents, containing at least one X-ray contrast-enhancing agent which is not a halogenated organic compound
• CPC Class Codes: A61L 24/001 Use of materials characterised by their function or physical properties
• CPC Class Codes: A61L 24/02 containing inorganic materials
• CPC Class Codes: A61L 2430/02 for reconstruction of bones; weight-bearing implants
• CPC Class Codes: A61L 27/12 Phosphorus-containing materials, e.g. apatite
• CPC Class Codes: A61L 27/50 Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials

Abstract

A bone cement comprises a powdery component including calcium phosphate and an aqueous liquid component. A radiopaque material is added to at least one of the powder and liquid components, and the components may be combined into a pasty substance for application to bone.

Claims

1. A cement preparation useful as bone substitute comprises a calcium phosphate powder which may be combined with an aqueous liquid, wherein the at least one of the powder or aqueous liquid is admixed with a radiopaque material prior to combination into the cement.

2. The preparation according to claim 1, further comprising a flowability enhancing additive for improving the flowability of the cement preparation after being combined with the liquid.

3. The preparation according to claim 1, wherein the admixed additive is combined with the calcium phosphate containing powder composition, whereby hardening characteristics of the cement preparation and/or mechanical properties of the hardened product are essentially not deteriorated.

4. The preparation according to claim 1, wherein the radiopaque material comprises a barium salt.

5. The preparation according to claim 4, wherein the barium salt is selected from the group consisting of barium sulfate, tribarium phosphate, barium jodide, barium zirconate and barium wolframate.

6. The preparation according to claim 1, wherein at least one of a metal, an inorganic metal compound, and a metal organic compound is admixed as the additive, wherein the metal or the metal compound is based on any metal element selected from the group consisting of iron, titanium, tantalum, gold, silver, rare earth elements, yttrium, ytterbium, zirconium, niobium, molybdenum, ruthenium, rhodium, palladium and tungsten.

7. The preparation according to claim 6, wherein the metal compound is selected from the group consisting of iron phosphate, iron oxide, iron hydroxide, and iron compounds with organic acids.

8. The preparation according to claim 1, wherein the additive comprises a compound of an element selected from the group of rare earth elements.

9. The preparation according to claim 1, wherein an iodo compound is admixed as the additive.

10. The preparation according to claim 9, wherein the iodo compound is an organic iodo compound of ionic or non-ionic type, preferably diatrizoate, ioxidalamate, iotamidol, iohexol or ioxaglate or a mixture thereof.

11. The preparation according to claim 1, wherein the admixed additive is a water soluble compound being admixed to the aqueous liquid component.

12. The preparation according to claim 11, wherein the metal or the metal oxide is admixed as the additive in a fine particulate form.

13. The preparation according to claim 1, wherein a sintered material, preferably sintered hydroxyapatite and/or sintered tricalcium phosphate, is admixed as the additive.

14. The preparation according to claim 1, wherein the additive for enhancing X-ray contrast is admixed in an amount of about 2.5 percent by weight to about 50 percent by weight relative to the total amount of the cement preparation.

15. The preparation according to claim 1, wherein the cement preparation comprises calcium, magnesium, and orthophosphates and optionally other salts of orthophosphoric acid as components of the composition.

16. The preparation according to claim 15, wherein the cement preparation further comprises an ammonium salt, preferably in the aqueous liquid component in the form of ammonium phosphate and/or ammonium hydrogen phosphate.

17. The preparation according to claim 1, wherein the cement preparation with the aqueous liquid is capable of providing a hardened cement which comprises at least one of the structural components selected from the group consisting of an apatite structure, a hydroxyapatite structure, a struvite structure and a tribarium phosphate structure.

23. The preparation according to claim 1 or the cement preparation according to claim 18, wherein a pharmaceutically and/or biologically active substance is further admixed to the cement preparation.

24. A hardened bone substitute material as obtained from the preparation according to claim 1 or the cement preparation according to claim 18.

25. The hardened bone substitute material according to claim 24, wherein the hardened cement comprises at least one of the structural components selected from the group consisting of an apatite structure, a hydroxyapatite structure, a struvite structure and a tribarium phosphate structure.

26. A use of the hardened bone substitute material according to claim 24 as bone implant, bone filler, bone cement or bone adhesive or as a therapeutic agent for the treatment of bone defects or osteoporosis.

27. A method for the treatment of bone defects or for the treatment of disease condition of the bone system, comprising a step of applying a formulation according to claim 1 or a cement preparation according to claim 18 to the defect site of a bone or a portion of the skeleton of a patient in need of such treatment.

28. The method according to claim 27, wherein the bone defect is applied to a vertebral body of the patient.

29. A process for the formation of a calcium phosphate containing cement, comprising the steps of:

mixing the powdery and liquid components of the formulation as defined in claim 1 or of the cement preparation as defined in claim 18;

and

allowing the obtained mixture to harden.

18. A cement preparation comprising a powdery component including an admixture of salts of calcium, magnesium, and orthophosphate to be admixed an aqueous liquid component, wherein the cement preparation further comprises at least one additive for enhancing the X-ray contrast selected from the group consisting of:

a barium salt;

metals and inorganic and organic metal compounds, preferably metal oxides, wherein the metal is selected from the group consisting of iron, titanium, tantalum, gold, silver, rare earth elements, yttrium, ytterbium, zirconium, niobium, molybdenum, ruthenium, rhodium, palladium and tungsten;

compounds of rare earth elements, preferably of gadolinium or cerium;

inorganic or organic iodo compounds; and

sintered hydroxyapatite and sintered tricalcium phosphate.

19. The cement preparation according to claim 18, wherein the additive is admixed as a fine particulate form to the powdery component of the cement preparation.

20. The cement preparation according to claim 18, wherein the additive is a water soluble compound and is admixed to the water or aqueous liquid component of the cement preparation.

21. The cement preparation according to claim 18, further comprising a strontium salt in the powders component.

22. The cement preparation according to claim 18, wherein the additive is a barium salt selected from the group consisting of barium sulfate, tribarium phosphate, barium jodide, barium zirconate and barium wolframate, and/or that the metal compound is selected from the group consisting of iron phosphate, iron oxide, iron hydroxide, and iron compounds with organic acids.