Patent ID: 6451021
Filing Date: 2002-09-17
Classification: A61B

Abstract:
A screw and coupling element assembly for use with an orthopedic rod implantation apparatus, comprising:a) a screw that has a head and a shaft that extends from the head; b) a coupling element that has a seat within which the head can be seated such that the shaft protrudes from the coupling element; and c) a locking element that can be mated with the coupling element and that thereafter can be selectively moved through a plurality of positions including an unlocked position and a locked position; wherein: d) when the locking element is in the unlocked position: (i) the locking element presents a rod-receiving channel, and (ii) the head is movable in the seat such that the shaft can be directed in a plurality of angles relative to the coupling element; and e) when the locking element is in the locked position: (i) a rod disposed within the rod-receiving channel is fixed relative to the coupling element, and (ii) the head is immovable in the seat such that the shaft is fixed at an angle relative to the coupling element; and wherein: f) the head has a distal portion defined by a compression surface; g) the locking element has a permissive surface that is presented to the compression surface when the locking element is in the unlocked position; h) when presented with the permissive surface, the compression surface is unhindered such that the head is movable in the seat; the locking element has a confrontational surface that is presented to the compression surface when the locking element is in the locked position; i) the confrontational surface is defined by a recess that has a recessed surface corresponding to the compression surface; and when the locking element is in the locked position: i) the locking element is compressed within the coupling element, ii) the compression surface is compressed by the confrontational surface such that the curvate proximal portion is compressed toward the bore and the head is immovable in the seat, and iii) the compression surface seats in the recess and thereby is biased against retreat from the recess.