US Patent 7722650 Variable angle spinal implant connection assembly

A variable angle connector for engaging a bone fastener to a spinal rod includes a body defining a channel for receiving the spinal rod and a set screw arrangement for clamping the rod within the channel. The body defines an engagement face configured for interdigitating engagement with the head of the bone fastener. The fastener is mounted on a post projecting from the engagement face of the body, with means for engaging the fastener to the post. The body of the connector includes a deformable portion at one portion of the engagement face that deforms when the set screw is tightened to clamp the rod within the rod channel. As the connector body deforms, the portion of the engagement face is brought into engagement with the head of the bone fastener.