Spinal fixation element rotation instrument

Patent metadata

Field	Value
Publication number	US-9788869-B2
Application number	US-39546909-A
Country	US
Kind code	B2
Filing date	Feb 27, 2009
Priority date	Feb 27, 2009
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

A spinal fixation element rotation instrument with two lever arms is provided. The lever arms are connected to each other at distal ends thereof. The second lever arm rotates relative to the first lever arm. The distal ends of the first and second lever arms are adapted to couple to a spinal fixation element. The distal ends of the lever arms may have a dual ratchet feature that prevents rotation in a set direction. When one arm rotates back and forth, the other arm is held stationary. As a result, the spinal fixation element rotates in a predetermined direction and is prevented from rotating back toward its initial position. The direction of the rotation of the spinal fixation element may be set using knobs or switches provided at a proximal end of one or both of the lever arms.

First claim

The invention claimed is:

1. An instrument for rotating a spinal fixation element having a notch at a proximal end comprising:
a first lever arm, wherein a distal end of the first lever arm is adapted to couple to the spinal fixation element; and
a second lever arm rotatably coupled to the first lever arm at the distal end thereof, a distal end of the second lever arm being adapted to couple to the spinal fixation element, wherein the second lever arm rotates relative to the first lever arm, about a central axis of the distal ends of the first lever arm and the second lever arm to rotate the spinal fixation element from an initial position to a rotated position,
wherein the first lever arm includes a first ratchet and the second lever arm includes a second ratchet forming a dual ratchet mechanism that prevents the spinal fixation element from rotating back toward the initial position;
a first switch provided on a proximal end of the first lever arm, wherein the first switch allows the first ratchet to rotate clockwise when the first switch is at a first position, and the first switch allows the first ratchet to rotate counterclockwise when the first switch is at a second position;
a second switch provided on a proximal end of the second lever arm, wherein the second switch allows the second ratchet to rotate clockwise when the second switch is at a first position, and the second switch allows the second ratchet to rotate counterclockwise when the second switch is at a second position;
wherein a first hole is formed in the distal end of the first lever arm, and a second hole is formed at the distal end of the second lever arm, and
an extension element having a proximal end that couples to the instrument by fitting through the first hole and the second hole, a distal end with a grabbing tip coupled to a carrier of the extension element for grabbing the spinal fixation element so that the spinal fixation element may be rotated by the instrument, a retractable sleeve surrounding the carrier, wherein in a retracted position of the retractable sleeve the grabbing tip is in an extended position and wherein in an advanced position the retractable sleeve is advanced over the carrier and the grabbing tip to prevent decoupling of the spinal fixation element from the extension element.

2. The instrument of claim 1 , wherein the second lever arm comprises:
a first section;
a second section; and
an attachment mechanism to attach the first section to the second section so that the first section is rotatable relative to the second section about a central axis of the attachment mechanism, wherein the central axis of the attachment mechanism is perpendicular to the central axis of the distal ends of the first lever arm and the second lever arm.

3. The instrument of claim 2 , wherein the attachment mechanism is a hinge.

4. The instrument of claim 2 , wherein the attachment mechanism is a loaded spring mechanism that allows the first section to assume one or more positions relative to the second section.

5. The instrument of claim 1 , wherein the instrument configured to receive the spinal fixation element in a portion of an opening provided at the distal end of the first lever arm and the second lever arm.

6. The instrument of claim 1 , wherein the distal ends of the first lever arm and the second lever arm are removable and replaceable.

7. The instrument of claim 1 , wherein the spinal fixation element is rotated clockwise when the first ratchet and the second ratchet are set to rotate clockwise.

8. The instrument of claim 1 , wherein the spinal fixation element is rotated counterclockwise when the first ratchet and the second ratchet are set to rotate counterclockwise.

9. The instrument of claim 1 , wherein the first ratchet and the second ratchet lock each other out so as to prevent the spinal fixation element from rotating when the first ratchet is set to rotate in a first direction and the second ratchet is set to rotate in a second direction opposite to the first direction.

Assignees

• Stad Shawn D
• Ramsay Christopher L
• Gamache Thomas
• Murphy Raymond F
• Depuy Synthes Products Inc

Inventors

• Stad Shawn D
• Ramsay Christopher L
• Gamache Thomas
• Murphy Raymond F

Classifications

• A61B17/8891

  at its periphery · CPC title

• A61B17/7085

  for insertion of a longitudinal element down one or more hollow screw or hook extensions, i.e. at least a part of the element within an extension has a component of movement parallel to the extension's axis · CPC title

• A61B17/701

  Longitudinal elements with a non-circular, e.g. rectangular, cross-section (A61B17/7005, A61B17/7007 take precedence) · CPC title

• A61B17/7011

  Longitudinal element being non-straight, e.g. curved, angled or branched (adjustable length longitudinal elements A61B17/7014; A61B17/7019 takes precedence, e.g. coil springs) · CPC title

• A61B17/7083 Primary

  Tools for guidance or insertion of tethers, rod-to-anchor connectors, rod-to-rod connectors, or longitudinal elements · CPC title