05885286 is referenced by 462 patents and cites 21 patents.

A multi-axial bone engaging fastener assembly includes a bone screw having a partially spherical head. The bone screw head is truncated at an upper surface in which a tool receiving recess is defined. The assembly includes a receiver member including a central bore that defines a tapered recess to receive the head of the bone screw. The bore of the receiver member also defines a channel communicating with the recess and configured to receive a spinal rod therein. A portion of the channel is threaded to receive a set screw above the rod. The assembly also includes a crown member disposed between the rod and the head of the bone screw. As the set screw is tightened into the receiver member, the set screw compresses the rod against the crown member, which presses the head of the bone screw into the tapered recess. In one embodiment, the head of the bone screw includes a flared edge that penetrates at least the crown member as the assembly is tightened. In another embodiment, the bone screw head includes a plurality of circumferential ridges configured to bite into the crown member. In a further aspect, the crown member is threaded to be inserted into the receiver member by threading through the threaded portion of the receiver member.

Title
Multi-axial bone screw assembly
Application Number
719161
Publication Number
5885286
Application Date
February 11, 1997
Publication Date
March 23, 1999
Inventor
Troy Drewry
Memphis
TN, US
Michael C Sherman
Memphis
TN, US
Agent
Woodard Emhardt Naughton Moriarty & McNett
Assignee
SDGI Holdings
DE, US
IPC
A61B 17/70
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