Patent ID: 11877776
Assignee: WARSAW ORTHOPEDIC, INC.
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 0:
1. A bone fastener comprising:
a. a head assembly comprising:
i. a first ring,
ii. a second ring, and
iii. a receiver having spaced apart arms that define an implant cavity, the implant cavity configured to receive a spinal rod, the receiver having an internal surface defining a first groove, a second groove spaced apart from the first groove, and a circumferential channel located in between the first groove and the second groove, wherein the first groove is configured to receive the first ring and the second groove is configured to receive the second ring; and

b. a screw shaft assembly having a head with planar outer surface portions, wherein the screw shaft assembly is restricted to a single plane of motion when the screw shaft assembly is engaged with the head assembly,
wherein the first ring is configured to move from the first groove and into the channel to prevent the second ring from moving into the channel.