Featuring a screw-based method of retraction that provides a fixed position to the anatomy. This simplified and flexible design allows for one-step, percutaneous placement of the screw and retractor, providing direct visualization and improved access for rod introduction. Features Direct Visualization and Access to the Screw Heads for Simple Rod Insertion Flexible Design Simplifying Multi-Level and L5-S1 Rod Insertion One-Step, Percutaneous Delivery of the Screw and Retractor Reducing Set-up Time Screw-Based Retractor Design Providing a Secure Method of Retraction Minimally Invasive Technique Reducing Potential for Musculature and Vascular Disruption Polymer Retractor Design Allowing for Neuromonitoring During Screw Insertion Used With the K2M TERRA NOVA® System for Direct Posterior Interbody Access