Patent ID: 11937854
Assignee: nan
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 0:
1. A receiver assembly for securing an elongate rod to a bone anchor via a threaded plug, the receiver assembly comprising:
a receiver having a longitudinal axis, a base portion, and an upper portion comprising a pair of upright arms defining a channel configured to receive the elongate rod, the channel extending between a front surface and a back surface of the receiver and communicating with a top surface defining a top of the receiver, the receiver having interior surfaces with a helically wound thread form formed in at least a portion of the interior surfaces and opposite outwardly-facing side surfaces on each of the upright arms, each of the outwardly-facing side surfaces having a planar surface that is parallel with respect to the planar surface of the opposite of the outwardly-facing side surfaces, the front and back surface of the receiver each including parallel planar surfaces with respect to each other; and
the threaded plug configured to be positioned within the channel to secure the elongate rod to the receiver in a locked configuration, the threaded plug comprising a cylindrical body having a central axis, an upper surface having a central drive structure, a lower surface, and an outer external surface with a mating continuous helically wound thread form formed on at least a portion of the outer external surface, the thread form of the threaded plug having a lower clearance surface and an outer crest surface forming at least a portion of an obtuse angle with respect to the lower clearance surface, the thread form of the threaded plug further including a load flank extending in at least one direction that slopes upwardly and outwardly relative to the central axis of the cylindrical body or perpendicular relative to the central axis and an inner root surface extending parallel to the central axis with a lower portion adjacent to and above a base of the thread form of the threaded plug and an upper portion adjacent to and below the base of the thread form of the threaded plug,
wherein the lower surface of the cylindrical body extends continuously between an outer circumference thereof and includes a centrally located downwardly extending solid portion configured to engage and lock the elongate rod in the channel of the receiver, and
wherein when the receiver assembly is in the locked configuration, the threaded plug does not extend over any part of the top surface defining the top of the receiver and the entire lower clearance surface and entire outer crest surface of the thread form of the threaded plug are spaced apart from the thread form of the receiver.