Bone anchor assembly with bone debris sweep ring in receiver sub-assembly

Abstract

A bone anchor assembly includes a bone anchor with a capture portion having a horizontal capture recess and an anchor portion opposite the capture portion, and a receiver with a central bore having a seat surface proximate a bottom opening and a channel for receiving a rod. The assembly also includes a ring retainer with a center aperture having a lower internal recess and an upper internal recess, an open sweep ring in the lower internal recess for sweeping the capture recess of bone debris when the capture portion is uploaded into the center aperture of the ring retainer, and an open capture ring in the upper internal recess for snapping into the swept capture recess of the bone anchor to capture and hold the capture portion of the bone anchor to the ring retainer. The ring retainer is positionable within the central bore of the receiver with its outer surface in frictional engagement with the seat surface to secure the captured bone anchor to the receiver.