Patent ID: 9119673
Filing Date: 2015-09-01
Classification: A61B

Abstract:
1. A spinal correction device adapted for use with a rod and a polyaxial screw having a ball-shaped head and a threaded end, the device comprising: a head-body and a cap, the head-body having a lower internal cavity to receive the ball-shaped head of the screw, an upper bore to receive a fixation rod therethrough, and an upper end configured to receive the unthreaded cap, wherein the cap comprises a cap rim, wherein the head-body comprises a head-body rim, and wherein the cap rim is configured to mate with and engage the head-body rim, wherein the cap rim varies in thickness around at least a portion of the perimeter of the cap, wherein the cap rim comprises at least one tapering section in which the cap rim thickness gradually varies; wherein the head-body and the unthreaded cap are configured such that: