Comparison of the 3D-printed operation guide template technique and the free-hand technique for S2-alar-iliac screw placement

Yonghui Zhao,Sheng Lu,Haotian Luo,Yongqing Xu,Jinlong Liang,Yulong Ma,Xingbo Cai

doi:10.1186/s12893-020-00930-5

Abstract

BackgroundTo compare the safety and accuracy of the 3D-printed operation guide template technique and the free-hand technique in the placement of the S2-alar-iliac (S2AI) screw.MethodsWe conducted a retrospective analysis of 47 patients undergoing S2AI screw placement in our hospital, divided into the 3D-printed operation guide template group and the free-hand screw placement group. The duration of single S2AI screw placement was documented in all patients. A postoperative CT scan was performed to assess screw placement effectiveness according to the distance from the screw tip to the breach of the cortical bone wall.ResultsIn total, 42 screws were placed in the guide template group, with an average screw placement duration of 151.6 ± 44.8 s. Screw placement grading was as follows: 40 screws in grade 0, two in grade 1, and none in grades 2 and 3. This grading resulted in excellent and good rates of 95.2% and 100%, respectively. In total, 52 screws were placed in the free-hand group, with an average screw placement duration of 138.3 ± 45.9 s. Screw placement grading was as follows: 42 screws in grade 0, seven in grade 1, three in grade 2, and none in grade 3. This grading resulted in excellent, good and acceptable rates 80.8%, 94.2% and 100%, respectively. Screw placement duration did not significantly differ between the groups (p > 0.05). The excellent rate of screw placement was greater in the guide template group than in the free-hand group (p < 0.05), but the good and acceptable rates did not significantly differ between the two groups (p > 0.05).ConclusionBoth techniques can be applied to S2AI screw placement. The 3D-printed guide technique is superior to the free-hand technique in terms of safety and accuracy.

Highlights

Pelvic internal fixation is the key to treating adult spine deformity, severe pelvic inclination, and severe lumbar spondylolisthesis [1]
This study focused on the application of the 3D-printed operation guide template technique and the free-hand technique guided by anatomical signs during operation in S2AI screw placement, comparing their safety and accuracy to provide a reference for clinical application
According to the size of the screw trajectory measured before surgery, appropriate screws were selected for screw placement, and the screw placement duration was documented

Summary

Introduction

Pelvic internal fixation is the key to treating adult spine deformity, severe pelvic inclination, and severe lumbar spondylolisthesis [1]. To solve the above problems, Sponseller et al proposed the S2-alariliac screw (S2AI) technique and achieved satisfactory results in adult and pediatric orthopedic surgeries [11, 12]. The advantages of this technique include less stripping of the soft tissues, a deeper screw position under the skin, no need for a connecting module during fixation, no hindrance to harvesting the ala of the ilium for grafting, achievement of biomechanical stability similar to that of ilial screw placement, and less intraoperative blood loss, postoperative infection, and pain [13, 14]. To compare the safety and accuracy of the 3D-printed operation guide template technique and the free-hand technique in the placement of the S2-alar-iliac (S2AI) screw

Methods

Results

Discussion

Conclusion