Polyaxial Bone Fixation Element

Patent metadata

Field	Value
Publication number	US-2021100590-A1
Application number	US-202017124625-A
Country	US
Kind code	A1
Filing date	Dec 17, 2020
Priority date	Jul 20, 2007
Publication date	Apr 8, 2021
Grant date	—

Abstract

The present disclosure includes a polyaxial bone fixation element for use in spinal fixation to interconnect a longitudinal spinal rod with a patient's vertebra. The polyaxial bone fixation element preferably includes a bone anchor, a collet, a body, and a locking cap. The polyaxial bone fixation element preferably enables in-situ assembly. That is, the polyaxial bone fixation element is preferably configured so that in use, the bone anchor may be secured to the patient's vertebra prior to being received within the body. Accordingly, the polyaxial bone fixation element enables a surgeon to implant the bone anchor without the body to maximize visibility and access around the anchoring site. Once the bone anchor has been secured to the patient's vertebra, the body can be snapped-onto the bone anchor. The bone anchor preferably also includes a second tool interface so that a surgical instrument can be directly coupled to the bone anchor.

First claim

What is claimed:

1 . A polyaxial bone fixation element for coupling a longitudinal spinal rod to a vertebra, the bone fixation element comprising:
a bone anchor including an enlarged, curvate head portion, wherein the head portion includes a first tool interface for engaging a first surgical instrument and a second tool interface for engaging a second surgical instrument, the first and second tool interfaces positioned in a head interface cavity; a body for interconnecting the bone anchor and the longitudinal spinal rod, the body having a longitudinal axis, an upper end with an upper opening, a lower end with a lower opening, a bore extending substantially between the upper opening and the lower opening, the bore having a first diameter D 1 , a rod-receiving channel for receiving the spinal rod located at the upper end, the rod-receiving channel having a channel axis that is oriented substantially perpendicular to the longitudinal axis, the body further including a lower edge portion adjacent the lower opening, the lower edge portion defining a second diameter D 2 smaller than the first diameter D 1 ; a collet including a first end, a second end and one or more slots extending from the second end, the slots defining a plurality of flexible arms, the collet movably positioned within the bore of the body; and a locking cap removably engageable with the body, the locking cap being movable from an unlocked position to a locked position wherein movement of the locking cap from the unlocked position to the locked position urges the rod against the collet and the flexible arms against the lower edge portion to secure a position of the bone anchor relative to the body.

Assignees

• Depuy Synthes Products Inc

Inventors

• Keyer Thomas
• Capozzoli Joseph
• Mcdivitt Eric

Classifications

• A61B17/7076

  for driving, positioning or assembling spinal clamps or bone anchors specially adapted for spinal fixation · CPC title

• A61B17/7037 Primary

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

• A61B17/864

  hollow, e.g. with socket or cannulated · CPC title

• A61B17/7082

  for driving, i.e. rotating, screws or screw parts specially adapted for spinal fixation, e.g. for driving polyaxial or tulip-headed screws · CPC title

• A61B17/8841

  Tools specially adapted to engage a prosthesis · CPC title