Polyaxial pedicle screw having provisional fastening means

Patent metadata

Field	Value
Publication number	US-10555759-B2
Application number	US-201715432111-A
Country	US
Kind code	B2
Filing date	Feb 14, 2017
Priority date	Sep 6, 2011
Publication date	Feb 11, 2020
Grant date	Feb 11, 2020

Abstract

A polyaxial pedicle screw includes a screwed shaft section for anchoring the pedicle screw in a vertebra, on one axial end of which a shaft head is configured which is coupled in a rotating and/or pivoting manner as well as in a tensile-force transmitting manner to a receiving sleeve for a longitudinal support. The receiving sleeve has a fastening means for selective positional fastening of the receiving sleeve with respect to the shaft section, the fastening means at least consisting of an inlay/pin mounted in the receiving sleeve and acting on the shaft head, and a locking element acting on the inlay/pin. The inlay/pin is configured with attachment points or engagement elements, which are not covered or overlapped by the locking element, for the provisional introduction of a compressive force on the inlay/pin parallel to the locking element.

First claim

The invention claimed is:

1. A polyaxial pedicle screw having a screwed shaft section for anchoring the pedicle screw in a vertebra,
wherein a shaft head is configured at an axial end of the screwed shaft section, said shaft head being pivotably and/or rotatingly coupled to a receiving sleeve for a longitudinal support,
wherein the receiving sleeve comprises a fastening means for selective positional fastening of the receiving sleeve with respect to the screwed shaft section, said fastening means at least comprising an inlay mounted in the receiving sleeve and acting on the shaft head, and a locking element acting via the longitudinal support on the inlay and screwed directly into the receiving sleeve,
wherein the inlay is configured with inlay engagement elements, which are not covered or overlapped by the locking element nor by the longitudinal support, for the introduction of a provisional compressive force parallel to the locking element on the inlay,
wherein the inlay engagement elements extend radially outwardly from an outermost circumference of the locking element in a direction perpendicular to the longitudinal axis of the locking element.

2. The polyaxial pedicle screw according to claim 1 , wherein the receiving sleeve comprises a sleeve body open on both sides whose sleeve wall is slotted in a U-shape starting from a proximal end face, whereby there occur two flanks lying radially opposite each other, wherein the inlay engagement elements are located between the two flanks.

3. The polyaxial pedicle screw according to claim 2 , wherein the inlay diametrically connects both of the U-shaped slots in the sleeve body.

4. The polyaxial pedicle screw according to claim 1 , wherein the inlay has an outline deviating from a circle, at least at one axial portion.

5. The polyaxial pedicle screw according to claim 1 , wherein the inlay is formed by an inlay sleeve, one end face of which is widened to a flange-like, oval or rectangular collar.

6. The polyaxial pedicle screw according to claim 5 , wherein the inlay is formed as a rectangular collar, wherein radially projecting lugs are configured at the inlay at corners of the rectangular collar, and wherein the radially projecting lugs constitute the inlay engagement elements.

7. The polyaxial pedicle screw according to claim 1 , wherein the receiving sleeve is configured or provided with at least one receiving sleeve engagement element via which an external provisional tensile force parallel to the locking element can be applied to the receiving sleeve.

8. The polyaxial pedicle screw according to claim 7 , wherein the at least one receiving sleeve engagement element forms an engagement undercut on an external sleeve-side of the receiving sleeve.

9. The polyaxial pedicle screw according to claim 7 , wherein the at least one receiving sleeve engagement element is provided with at least one indentation, pocket, undercut or strip-shaped projection.

10. The polyaxial pedicle screw according to claim 7 , wherein the at least one receiving sleeve engagement element is provided with two axially spaced indentations, pockets, undercuts or strip-shaped projections.

11. The polyaxial pedicle screw according to claim 1 , wherein the inlay engagement elements are configured as inlay engagement elements having form-locking fit in a plane perpendicular to an axial direction of the receiving sleeve.

12. The polyaxial pedicle screw according to claim 1 , wherein a front face of the inlay is widened to a flange-like collar or formed as a concave trough.

13. A polyaxial pedicle screw having a screwed shaft section for anchoring the pedicle screw in a vertebra,
wherein a shaft head is configured at an axial end of the screwed shaft section, said shaft head being pivotably and/or rotatingly coupled to a receiving sleeve for a longitudinal support,
wherein the receiving sleeve comprises a fastening means for selective positional fastening of the receiving sleeve with respect to the screwed shaft section, said fastening means at least comprising an inlay mounted in the receiving sleeve and acting on the shaft head, and a locking element acting via the longitudinal support on the inlay and screwed directly into the receiving sleeve,
wherein the inlay is configured with inlay engagement elements, which are not covered or overlapped by the locking element or by the longitudinal support, for introduction of a provisional compressive force parallel to the locking element on the inlay,
wherein the receiving sleeve is configured or provided with at least one receiving sleeve engagement element via which an external provisional tensile force parallel to the locking element can be applied to the receiving sleeve,
wherein the inlay comprises a rectangular collar, wherein radially projecting lugs are configured at the inlay at corners of the rectangular collar, and wherein the radially projecting lugs constitute the inlay engagement elements.

14. The polyaxial pedicle screw according to claim 13 , wherein the at least one receiving sleeve engagement element forms an undercut on an external sleeve-side of the receiving sleeve.

15. The polyaxial pedicle screw according to claim 13 , wherein the at least one receiving sleeve engagement element is provided with at least one indentation, pocket, undercut or strip-shaped projection.

16. The polyaxial pedicle screw according to claim 15 , wherein the at least one receiving sleeve engagement element is provided with two axially spaced indentations, pockets, undercuts or strip-shaped projections.

17. A polyaxial pedicle screw having a screwed shaft section for anchoring the pedicle screw in a vertebra,
wherein a shaft head is configured at an axial end of the screwed shaft section, said shaft head being pivotably and/or rotatingly coupled to a receiving sleeve for a longitudinal support,
wherein the receiving sleeve comprises a fastening means for selective positional fastening of the receiving sleeve with respect to the screwed shaft section, said fastening means at least comprising an inlay mounted in the receiving sleeve and acting on the shaft head, and a locking element acting via the longitudinal support on the inlay and screwed directly into the receiving sleeve,
wherein the inlay is configured with inlay engagement elements, which are not covered or overlapped by the locking element or by the longitudinal support, for introduction of a provisional compressive force parallel to the locking element on the inlay,
wherein the inlay engagement elements are configured as inlay engagement elements providing form-locking fit in a plane perpendicular to an axial direction of the receiving sleeve, and
wherein the inlay engagement elements are each formed as a concentric trough, hollow or recess having an indentation in the axial direction of the receiving sleeve providing form locking fit in all directions in the plane perpendicular to the axial direction of the receiving sleeve.

18. The polyaxial pedicle screw according to claim 17 , wherein each concentric trough, hollow or recess defines an opening facing a proximal end of the receiving sleeve.

19. The polyaxial pedicle screw according to claim 17 , wherein the inlay is formed such that it projects or is exposed, at least in portions, radially outwardly beyond an outermost circumference of the locking element in a direction perpendicular to a longitudinal axis of the locking element, whereby the inlay engagement elements occur at these radial portions which are not covered or overlapped by the locking element.

Assignees

• Aesculap Ag

Inventors

• Krüger Sven

Classifications

• A61B17/7032 Primary

  Screws or hooks with U-shaped head or back through which longitudinal rods pass · CPC title

• A61B17/708

  with tubular extensions coaxially mounted on the bone anchors · CPC title

• A61B17/7035 Primary

  Screws or hooks, wherein a rod-clamping part and a bone-anchoring part can pivot relative to each other · CPC title

• A61B17/7002

  Longitudinal elements, e.g. rods · CPC title

• A61B17/7037

  wherein pivoting is blocked when the rod is clamped · CPC title