US Patent Issued on Aug. 5 for "Pivotal bone anchor assembly with ring retainer and twist-in-place pressure insert" (Kansas Inventor)

ALEXANDRIA, Va., Aug. 6 -- United States Patent no. 12,376,894, issued on Aug. 5.

"Pivotal bone anchor assembly with ring retainer and twist-in-place pressure insert" was invented by Roger P. Jackson (Prairie Village, Kan.).

According to the abstract* released by the U.S. Patent & Trademark Office: "A pivotal bone anchor assembly includes a receiver having an internal cavity with a circumferential groove adjacent a bottom opening, an upper channel with a downward-facing surface below a closure mating structure, and an internal cylindrical surface with a fixed rotation abutment surface. The assembly also includes an insert positionable into the upper channel having outer side surfaces of upstanding arms with a protruding abutment structure...