Comparison of Radiographic And Clinical Outcomes Observed After Adult Spinal Deformity Correction Using Iliac Screw Versus S2-Alar-Iliac Screw

Abstract

Background: To date, there is a paucity of reports clarifying the change of spinopelvic parameters in patients with adult spinal deformity (ASD) who underwent long segment spinal fusion using iliac screw (IS) and S2-alar-iliac screw (S2AI) fixation.Methods: A retrospective review of consecutive patients underwent deformity correction surgery for ASD between 2013 and 2017 was performed. Patients were divided into two groups based on whether IS or S2AI fixation was performed. All radiographic parameters were measured preoperatively, immediately postoperatively, and the last follow-up. Demographics, intraoperative and clinical data were analyzed between the two groups. Additionally, the cohort was subdivided according to the postoperative change in pelvic incidence (PI): subgroup (C) was defined as change in PI ≥5° and subgroup (NC) with change <5°. In subgroup analyses, the 2 different types of postoperative change of PI were directly compared.Results: A total of 142 patients met inclusion criteria: 111 who received IS and 31 received S2AI fixation. The IS group (65.6 ± 26, 39.8 ± 13.8) showed a significantly higher change in lumbar lordosis (LL) and upper lumbar lordosis (ULL) than the S2AI group (54.4 ± 17.9, 30.3 ± 9.9) (p<0.05). In subgroup (C), PI significantly increased from 53° preoperatively to 59° postoperatively at least 50% of IS cohort, with a mean change of 5.8° (p<0.05). The clinical outcomes at the last follow-up were significantly better in IS group than in S2AI group in terms of VAS scores for back and leg. The occurrence of sacroiliac joint pain and pelvic screw fracture were significantly greater in S2AI group than in IS group (25.8% vs 9%, p<0.05) and (16.1% vs 3.6%, p<0.05).Conclusions: IS fixation showed a greater change in LL and ULL than S2AI fixation in ASD surgery. PI may be changed under certain circumstances.

Study of Sacroiliac fixation in patients with sacroiliitis associated with L5 Lythesis

“…Additionally, the post-operative ODI (31.7 19.2) was significantly lower than the pre-operative ODI (66.2 11.1) (high statistical significance; p-value 0.001). This was in agreement with Luo et al, 8 who revealed that both VAS score for back and leg and ODI were significantly improved in S2AI group.Also, Elder et al, 11 revealed that VAS score as well as ambulatory status was significantly improved in S2AI group.…”

“…This was in agreement with Luo et al, 8 who revealed that in S2AI group the mean difference VAS of back were 4.46 and for leg were 3.99. Also, Ishida et al, 10 reported that in S2AI group the mean difference VAS was 2.6 + 2.0.…”

“…As regard pre-operative ODI, the mean pre-operative ODI of all studied patients was 66.2 ± 11.1 with minimum pre-operative ODI of 44 and maximum pre-operative ODI of 78. However, Luo et al, 8 reported that in S2AI group, the mean pre-operative VAS was (7.55 ± 3.12 for back and 7.31 ± 2.52 for leg) and the mean preoperative ODI 48.24 ± 19.67. there was no statistically significant difference between the S2AI and IS groups as regard preoperative VAS and ODI.…”

“…However, Luo et al, 8 reported that in S2AI group, there were 6.5% have L1/2 fusion level, 87% have L2/3, 93.5 have L3/4, 97% have L4/5 and 97% have L5/S1. There was no statistically significant difference between the S2AI and IS groups as regard Interbody fusion level.…”