Sacropelvic Fixation with S2-Alar-Iliac (S2AI) Screws Via CT-guided Navigation

Sacropelvic fixation is frequently used for the correction of complex pediatric spine deformities.S2-alar-iliac (S2AI) screws are a powerful method to obtain iliac fixation.Advantages include a medialized starting point that requires less soft tissue dissection, no need for connectors to the rod, and reduced screw head prominence.Though the technique for S2AI placement under free-hand and fluoroscopic techniques has been described, there is limited description of computed tomography (CT)-guided technique for the placement of S2AI screws in pediatric patients undergoing surgery for complex spinal deformity.The goal of this paper is to describe the technique for placement of S2AI screws via CT-guided navigation and compare it to traditional fluoroscopy and free-hand techniques. Key Concepts• Sacral fixation is often needed in children with neuromuscular disorders as a result of pelvic obliquity.• Sacro-alar-iliac fixation provides superior fixation and may help avoid complications such as failure of fixation and nonunion at the spine-pelvis junction.• Surgical navigation has been used to place pedicle screws for fixation and can help achieve safe and stable fixation, especially when instrumenting complex spinal anatomy.• Similarly, surgical navigation may facilitate efficient placement of large sacro-alar iliac screws and this manuscript demonstrates that methodology.