05882350 is referenced by 383 patents and cites 5 patents.

A polyaxial orthopedic device for use with rod implant apparatus includes a screw having a curvate head, a two-piece interlocking coupling element which mounts about the curvate head, and a rod receiving cylindrical body member having a tapered socket into which both the screw and the interlocking coupling element are securely nested. The interlocking coupling element includes a socket portion which is slotted and tapered so that when it is radially compressed by being driven downwardly into the tapered socket in the cylindrical body it crush locks to the screw. The securing of the rod in the body member provides the necessary downward force onto the socket portion through a contact force on the top of the cap portion. Prior to the rod being inserted, therefore, the screw head remains polyaxially free with respect to the coupling element and the body. In a preferred embodiment, the cap portion and the socket portion are formed and coupled in such a way that when the cap portion is compressed toward the socket portion, there is an additional inward radial force applied by the cap portion to the socket portion, thereby enhancing the total locking force onto the head of the screw.

Title
Polyaxial pedicle screw having a threaded and tapered compression locking mechanism
Application Number
421087
Publication Number
5882350
Application Date
January 2, 1998
Publication Date
March 16, 1999
Inventor
Stephen Tatar
Montvale
NJ, US
James D Ralph
Oakland
NJ, US
Agent
Joseph P Errico Esq
Assignee
Fastenetix
NJ, US
IPC
A61B 17/70
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