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Updated: Feb 8, 2026

A Spine Robotic-Assisted Navigation System for Pedicle Screw Placement
Published on: May 11, 2020
Fluoroscopy only for the placement of long iliac screws: A study on 14 patients
Marcelo D Vilela1,2, Bruno P Braga3, Hugo A S Pedrosa1,4
1Department of Neurosurgery, Hospital Mater Dei, Belo Horizonte, Brazil.
Background:
Iliac screw placement is challenging due to the particular anatomy of the ilium. Most series have reported the use of relatively short (≤90 mm in length) screws despite a long iliac buttress, which has an average length of 129 mm in females and 141 mm in males. This study describes a series of 14 patients who underwent placement of long iliac screws (≥100 mm in length) as part of a spinopelvic fusion utilizing fluoroscopy alone.
Methods:
All patients who received at least one long iliac screw were included in this study. Placement accuracy, the average distance from the screw tip to the anterior inferior iliac spine (AIIS), neurovascular injuries, acetabulum and/or sciatic notch violations, and screw prominence were all measured.
Results:
Fourteen patients received 38 iliac screws, with 31 screws being ≥100 mm in length. The accuracy rate was 87.1% (27/31) for the long iliac screws. The average shortest distance from the iliac screw tip to the AIIS was 15.5 mm for the right-sided and 17.1 mm for the left-sided ilia. There were no neurovascular injuries, acetabulum, or sciatic notch violations, and no screws loosened or fractured. Of interest, only one patient required off-set connectors to link the rods to the iliac screws.
Conclusions:
Placement of long iliac screws under intraoperative fluoroscopy only was shown to be feasible, with a high accuracy rate and few complications, in this series of patients.
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