Device and method for storing and mixing a bone cement

Patent metadata

Field	Value
Publication number	US-10307195-B2
Application number	US-201615281224-A
Country	US
Kind code	B2
Filing date	Sep 30, 2016
Priority date	Oct 2, 2015
Publication date	Jun 4, 2019
Grant date	Jun 4, 2019

Abstract

Devices and methods mix a bone cement and comprise at least one cartridge, wherein the cartridge comprises in its interior a cylindrical mixing chamber, a discharge piston movable in the cylindrical mixing chamber in the longitudinal direction and sealable against the walls of the mixing chamber, a mixing device for thoroughly mixing the content of the mixing chamber, which is arranged in the interior of the mixing chamber. The mixing device is operable externally via a mixing rod and the mixing rod is guided through a passage in the discharge piston such that it can be rotated and displaced in the longitudinal direction by the discharge piston. The cartridge comprises a discharge opening opposite the discharge piston, wherein, in the mixing chamber, a first component is contained between the discharge piston and the discharge opening, wherein a monomer fluid as a second component is introducable through the discharge opening into the mixing chamber. The device further comprises a locking element with which the mixing rod is affixable to the discharge piston such that the discharge piston is movable by means of the mixing rod in the mixing chamber in the longitudinal direction.

First claim

The invention claimed is:

1. A device for mixing a bone cement, the device comprising
at least one cartridge comprising, in its interior, a cylindrical mixing chamber,
a discharge piston movable, in the cylindrical mixing chamber, in the longitudinal direction and sealed against walls of the mixing chamber,
a mixing device, for mixing the content of the mixing chamber, arranged in an interior of the mixing chamber, wherein the mixing device operable externally via a mixing rod and the mixing rod is guided through a passage in the discharge piston such that the mixing rod is rotatable and displacable in the longitudinal direction by the discharge piston,
wherein the at least one cartridge further comprises a discharge opening opposite the discharge piston, wherein, in the mixing chamber, a first component of the bone cement is contained between the discharge piston and the discharge opening, wherein a monomer fluid as a second component of the bone cement is introducable through the discharge opening into the mixing chamber,
wherein the device comprises a locking element with which the mixing rod is affixable or is affixed to the discharge piston such that the discharge piston is movable by means of the mixing rod in the mixing chamber in the longitudinal direction,
and further wherein the discharge piston comprises a gas impermeable upper side that faces away from the discharge opening and a gas permeable underside, that is impermeable for powder particles, that faces towards the discharge opening, wherein the gas permeable underside is connected via at least one passage in the discharge piston with at least one side opening in the side surface of the discharge piston, such that the mixing chamber is gas-permeably connected with the environment of the cartridge, when the at least one opening in the side surface of the discharge piston is not covered by the inner wall of the mixing chamber of the cartridge.

2. The device according to claim 1 , wherein the mixing rod with the locking element is detachably affixable or is detachably affixed to the discharge piston.

3. The device according to claim 1 , wherein, in the discharge opening or in front of the discharge opening, a filter is provided that is impermeable for powder but permeable for fluids, which closes or covers the discharge opening.

4. The device according to claim 1 , wherein at least one latching element is provided on the discharge piston, which grips into at least one counter-latching means on the cartridge such that the discharge piston can no longer be moved in the direction away from the discharge opening beyond the at least one latching position.

5. The device according to claim 4 , wherein at least one of the at least one latching element is operable externally via at least one operating element.

6. The device according to claim 1 , wherein the discharge piston comprises an upper circumferential seal between the gas impermeable upper side of the discharge piston and the at least one side opening and a lower circumferential seal between the gas permeable underside and the at least one side opening, which seal the discharge piston against the inner wall of the mixing chamber, or are suitable for sealing the discharge piston against the inner wall of the mixing chamber, when the discharge piston has been inserted sufficiently deeply into the cartridge in the direction of the discharge opening.

7. The device according to claim 4 , wherein at least two latching positions are provided for the discharge piston, wherein the at least one side opening lies exposed in a first latching position and in a second latching position, the at least one side opening is covered.

8. The device according to claim 1 , wherein, on the mixing rod, a manually operated actuation element is attached.

9. The device according to claim 1 , wherein the locking element is a screw cap which encloses the mixing rod and which is screwable onto or into a counter-thread on the discharge piston such that the screw cap or the passage through the discharge piston presses onto the mixing rod such hat the mixing rod is affixed against the discharge piston, or the locking element is at least one pin which is to be inserted through at least one passage in the mixing rod, or which is to be inserted into at least one recess in the mixing rod, so that the mixing rod is no longer insertable into the mixing chamber.

10. The device according to claim 1 , wherein the free volume in the mixing chamber which is not taken up by the first component and the discharge piston when the discharge piston is arranged in the cartridge at a maximum distance in the direction away from the discharge opening is at least as large as the volume of the monomer fluid to be introduced and all connection lines provided between the monomer fluid and the mixing chamber.

11. The device according to claim 1 , wherein the mixing rod comprises a predetermined breaking point that is arranged directly above the upper side of the discharge piston or the locking element when the mixing rod is pulled out of the mixing chamber such that the mixing device lies on the underside of the discharge piston.

12. A cementing device, for storing the initial components of a bone cement and for mixing the bone cement, comprising the device according to claim 1 and a connection line connected to the discharge opening and which connects the mixing chamber in a fluid permeable manner with a vessel, wherein, in the vessel, a monomer vessel with a monomer fluid contained therein can be inserted or is contained, wherein the monomer vessel should be opened in the device and the monomer fluid should be suctioned into the mixing chamber through the connection line by an underpressure which is generated in the mixing chamber by a movement of the discharge piston away from the discharge opening.

13. The cementing device according to claim 12 , wherein, in the vessel, at least one passage is provided, wherein the at least one passage connects the vessel with the environment in a gas permeable manner.

14. The cementing device according to claim 12 , further comprising an opening device with which the monomer vessel should be opened in the vessel without hereby opening the device or without hereby opening the vessel.

15. The cementing device according to claim 12 , further comprising a foot part that is connected to the cartridge and on which the vessel is also attached.

16. The device according to claim 4 , wherein the at least one latching element is arranged on a side sheath surface of the discharge piston and the at least one counter-latching means is arranged on the inner wall of the mixing chamber.

17. The device according to claim 5 , wherein the operating element is connected to the at least one of the at least one latching element and protrudes over the upper edge of the cartridge, wherein the upper edge of the cartridge lies opposite the discharge opening.

18. The device according to claim 17 , wherein the operating element is connected as a single piece with the at least one of the at least one latching element.

19. The device according to claim 7 , wherein, in the first latching position, the discharge piston is only sealed against the mixing chamber by the lower circumferential seal, and, in the second latching position, the discharge piston is sealed against the mixing chamber by the upper and lower seal.

20. The device according to claim 1 , wherein the locking element is at least one pin which is to be inserted through at least one passage in the mixing rod,

Assignees

• Heraeus Medical Gmbh

Inventors

• Vogt Sebastian

Classifications

• A61B2090/037

  with a frangible part, e.g. by reduced diameter · CPC title

• A61B17/8833 Primary

  Osteosynthesis tools specially adapted for handling bone cement or fluid fillers; Means for supplying bone cement or fluid fillers to introducing tools, e.g. cartridge handling means · CPC title

• A61B2017/8838

  for mixing bone cement or fluid fillers · CPC title

• A61B17/8802

  Equipment for handling bone cement or other fluid fillers · CPC title

• A61B17/8827

  with filtering, degassing, venting or pressure relief means · CPC title