Sacropelvic Fixation for Adult Deformity Surgery Comparing Iliac Screw and Sacral 2 Alar-Iliac Screw Fixation: Systematic Review and Updated Meta-Analysis

Two commonly used techniques for spinopelvic fixation in adult deformity surgery are iliac screw (IS) and sacral 2 alar-iliac screw (S2AI) fixations. In this article, we systematically meta-analyzed the complications of sacropelvic fixation for adult deformity surgery comparing IS and S2AI. The PubMed, Embase, Web of Science, and Cochrane clinical trial databases were systematically searched until March 29, 2023. The proportion of postoperative complications, including implant failure, revision, screw prominence, and wound complications after sacropelvic fixation, were pooled with a random-effects model. Subgroup analyses for the method of sacropelvic fixation were conducted. Ten studies with a total of 1,931 patients (IS, 925 patients; S2AI, 1,006 patients) were included. The pooled proportion of implant failure was not statistically different between the IS and S2AI groups (21.9% and 18.9%, respectively) (p = 0.59). However, revision was higher in the IS group (21.0%) than that in the S2AI group (8.5%) (p = 0.02). Additionally, screw prominence was higher in the IS group (9.6%) than that in the S2AI group (0.0%) (p < 0.01), and wound complication was also higher in the IS group (31.7%) than that in the S2AI group (3.9%) (p < 0.01). IS and S2AI fixations showed that both techniques had similar outcomes in terms of implant failure. However, S2AI was revealed to have better outcomes than IS in terms of revision, screw prominence, and wound complications.