A comparative study of fixation failure between iliac screws and second sacral alar-iliac screws in patients with adult spinal deformity surgery
10.3760/cma.j.cn121113-20241226-00762
- VernacularTitle:髂骨钉与经第2骶椎骶髂螺钉固定治疗成人脊柱畸形术后失败的对比研究
- Author:
Bangheng LIANG
1
;
Jie LI
;
Yanjie XU
;
Changsheng FAN
;
Zezhang ZHU
;
Yong QIU
;
Zhen LIU
Author Information
1. 南京医科大学鼓楼临床医学院骨科脊柱外科,南京 210008
- Publication Type:Journal Article
- Keywords:
Spinal curvatures;
Spinal fusion;
Postoperative complications;
Pelvic fixation
- From:
Chinese Journal of Orthopaedics
2025;45(18):1169-1176
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To compare the incidence of instrumentation-related complications and health-related quality of life following pelvic fixation using iliac screws (IS) or second sacral alar-iliac (S 2AI) screws in adult spinal deformity (ASD). Methods:A retrospective cohort study was conducted on 108 ASD patients who underwent posterior corrective fusion and fixation extending to the pelvis at Nanjing Drum Tower Hospital between September 2010 and April 2021. According to the type of pelvic fixation, patients were divided into an IS group ( n=34; 12 males, 22 females; mean age 53.7±11.1 years, range 28-73 years) and an S 2AI group ( n=74; 23 males, 51 females; mean age 52.8±8.6 years, range 27-72 years). Pre- and post- operative standing anteroposterior and lateral radiographs were evaluated for Cobb angle, coronal balance distance (CBD), thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). At 2 years postoperatively, health-related quality of life were assessed using the Scoliosis Research Society-22 questionnaire (SRS-22), Oswestry disability index (ODI), and visual analogue scale (VAS) for pain. Instrumentation failure related to pelvic fixation during follow-up was recorded. Results:All patients completed follow-up. Mean follow-up duration was 28.5±3.6 months (range 24-37 months) in the IS group and 28.1±4.3 months (range 24-43 months) in the S 2AI group. Postoperatively, both groups showed significant improvement in Cobb angle, CBD, TK, LL, SVA, PT, and SS compared to baseline ( P<0.05), whereas PI remained unchanged ( t=0.664, P=0.509; t=1.227, P=0.222). Preoperative PT was greater in the IS group than in the S 2AI group (33.6°±8.7° vs. 29.3°±9.6°, t=2.228, P=0.028). No significant intergroup differences were observed in any other pre- or post- operative radiographic parameters ( P>0.05). Pelvic fixation failure occurred in 31 patients (28.7%, 31/108). Patients with fixation failure had a longer fusion segment extension than those without failure (12.0±2.8 vs. 10.8±2.4 segments; t=2.256, P=0.026). In the IS group, complications comprised 3 cases of screw loosening (8.8%), 2 of screw breakage (5.9%), and 4 of rod fracture within the pelvic region (11.8%), including 1 case with concurrent screw and rod failure. In the S 2AI group, there were 21 cases of screw loosening (28.4%) and 2 of screw breakage (2.7%). Screw loosening was less frequent in the IS group than in the S 2AI group (χ 2=5.154, P=0.023), whereas pelvic rod fracture was more common in the IS group (χ 2=9.041, P=0.003). Screw breakage rates did not differ significantly ( P>0.05). Mean VAS, ODI, and SRS-22 scores in the IS group were 3.2±2.4, 24.9%±18.8%, and 3.2±0.8, respectively; corresponding to 2.5±1.8, 18.9%±10.9%, and 3.3±0.6 in the S 2AI group. ODI was significantly higher in the IS group ( t=2.062, P=0.042), whereas VAS and SRS-22 were comparable ( P>0.05). Among S 2AI patients, VAS and ODI scores did not differ significantly between those with and without screw loosening ( P>0.05). Conclusions:The post-operative incidence of pelvic fixation failure following ASD surgery reached 28.7%. The predominant failure mode with S 2AI was screw loosening, whereas IS was more frequently complicated by rod fracture. Early postoperative health-related quality of life was superior with S 2AI screws compared with iliac screws.