05669911 is referenced by 393 patents and cites 1 patents.

A polyaxial orthopedic device for use with rod implant apparatus includes a screw having a curvate head, a locking collar disposed therearound, and a receiving member having a linearly tapered tapered socket in which the screw and the collar are nested. The locking collar is slotted and tapered, and has a semi-spherical interior volume into which the screw head is initially polyaxially held. The receiving member has a transverse channel formed in it for receiving a rod, and an axial bore having a linearly tapered chamber in the bottom portion thereof. The collar is inserted down the bore from the top to seat in the chamber, and the screw is subsequently inserted up through the bottom of the bore and into the collar. The linear taper of the chamber provides a radially inward force on the locking collar when the collar is forced downward therein. This radially inward force causes the locking collar to crush lock against the head of the screw, therein locking the two at the given angulation. It is the placement of the rod in the transverse channel, against the top of the collar, and the subsequent locking down of the rod in the channel which provides the downward force against the locking collar, which in turn locks the screw in its given angulation.

Title
Polyaxial pedicle screw
Application Number
421087
Publication Number
5669911
Application Date
June 13, 1996
Publication Date
September 23, 1997
Inventor
James D Ralph
Oakland
NJ, US
Thomas J Errico
Summit
NJ, US
Joseph P Errico
Far Hills
NJ, US
Agent
Joseph P Errico
Assignee
Fastenetix L L C
NJ, US
IPC
A61B 17/70
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