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Updated: Feb 15, 2026

A Teleoperated Robotic System-Assisted Percutaneous Transiliac-Transsacral Screw Fixation Technique
Published on: January 6, 2023
S-1 alar/iliac screw technique for spinopelvic fixation
J Mason DePasse1, Mauricio Valdes2, Mark A Palumbo3
11Department of Orthopaedics, Alpert Medical School of Brown University, Providence, Rhode Island; and.
Abstract:
Spinopelvic fixation provides an important anchor for long fusions in spinal deformity surgery, and it is also used in the treatment of other spine pathologies. Iliac screws are known to sometimes require reoperation due to pain resulting from hardware prominence and skin injury. S-2 alar/iliac (S2AI) screws do not often require removal, but they may provide inadequate fixation in select cases. In this paper the authors describe a technique for S-1 alar/iliac screws that may be used independently or as a supplement to S2AI screws. A preliminary biomechanical analysis and 2 clinical case examples are also provided.
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