Patent ID: 8337530

Claim:
A method of assembling a polyaxial bone anchor, the method comprising: providing an upper housing having a bore extending vertically therethrough, the upper housing including a plurality of plastically deformable tabs circumferentially around a lower end of the upper housing in a first radially unexpanded state, each tab having a portion that extends radially outward beyond a radial extent of the bore and a portion that extends radially inside the bore in the first radially unexpanded state; providing a lower housing having a lip proximate an upper end of the lower housing; placing the lower housing beneath the upper housing so that the lip is radially adjacent the tabs; inserting a mandrel downward through the bore in the upper housing; forcing the tabs radially outward with the mandrel to a second radially expanded state, each tab on the upper housing plastically deforming radially outward and engaging the lip on the lower housing; and withdrawing the mandrel from the upper housing, wherein the tabs remain in the second radially expanded state upon withdrawing the mandrel from the upper housing.