Anti-backout mechanism
AssigneeDePuy Spine, Inc.
InventorsPaul S. Maguire, Douglas L. Hester
Life of this patent
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Abstract
Methods and devices for locking a fastener in a thru-bore are provided herein. In one exemplary embodiment, a spinal anchor is provided that includes a bone engaging fastener, an anti-backout mechanism, and a locking mechanism. The anti-backout mechanism can be movable between a retracted position in which it is disposed within the fastener and a deployed position in which is extends from the bone engaging fastener. The locking mechanism can be matable to the bone engaging fastener and can be configured to move the anti-backout mechanism from the retracted position to the deployed position. In the deployed position, the anti-backout mechanism can prevent the bone engaging fastener from backing out of a thru-bore in a spinal plate.
Claims20
A spinal anchor, comprising:
- a bone engaging fastener having a threaded shank with a head formed thereon and configured to sit in a thru-bore in a spinal plate;
- an anti-backout mechanism disposed within the head of the bone engaging fastener and movable between a retracted position in which the anti-backout mechanism is retracted into the bone engaging fastener, and a deployed position in which the anti-backout mechanism extends from the bone engaging fastener, the anti-backout mechanism being biased to the retracted position;
- and
- a locking mechanism matable to the bone engaging fastener and configured to move the anti-backout mechanism from the retracted position to the deployed position;
- wherein the locking mechanism includes an elongate member extending distally therefrom such that the elongate member extends through the anti-backout mechanism to maintain alignment between the locking mechanism and the bone engaging fastener;
- and
- wherein the anti-backout mechanism comprises a leaf spring.
A spinal fixation kit, comprising:
- a spinal plate having at least one thru-bore formed therein;
- a bone engaging fastener having a head disposable within the at least one thru-bore in the spinal plate and having an anti-backout mechanism disposed therein;
- and
- a locking mechanism matable to the bone engaging fastener and configured to cause the anti-backout mechanism to extend from the bone engaging fastener to engage at least one of the spinal plate and a bushing disposed within the spinal plate when the head is seated therein to prevent the bone engaging fastener from backing out of the thru-bore in the spinal plate;
- wherein a distal portion of the locking mechanism is configured to extend through a bore formed in the anti backout mechanism to maintain alignment between the locking mechanism and the bone engaging fastener;
- and
- wherein the anti-backout mechanism comprises a leaf spring.
A spinal anchor, comprising:
- a bone engaging fastener having a shank with a head formed thereon and configured to sit in a thru-bore in a spinal plate;
- an anti-backout mechanism disposed within the bone engaging fastener and movable between a retracted position in which the anti-backout mechanism is retracted into the bone engaging fastener, and a deployed position in which the anti-backout mechanism extends from the bone engaging fastener, the anti-backout mechanism being biased to the retracted position;
- and
- a set screw having an elongate member extending distally therefrom, the set screw being matable to the bone engaging fastener such that distal advancement of the set screw within the bone engaging fastener causes the anti-backout mechanism to move from the retracted position to the deployed position;
- wherein the elongate member extends through the anti-backout mechanism to maintain alignment between the set screw and the bone engaging fastener;
- and
- wherein the anti-backout mechanism comprises a leaf spring.
Dependencies are inferred from the claim text.