Wiltse approach assisted by O-arm three-dimensional CT navigation in treatment of Lenke 5C Idiopathic Scoliosis / 中华骨科杂志

ABSTRACT

Objective To explore the feasibility and efficacy of posterior minimally invasive scoliosis surgery in Lenke 5C adolescent idiopathic scoliosis (AIS).Methods From November 2012 to March 2014,a total of 16 patients underwent posterior minimally invasive scoliosis surgery assisted by O-arm three-dimensional CT navigation were included.There were 14 female and 2 male,with an average age of (16.7± 1.6) years (ranged from 14 to 18 years).The mean Cobb angles of lumbar and thoracic curve were 48.7°±5.6°and 24.1°±5.4°,respectively.Results 16 patients were successfully completed the operation,the average operation time was (246±89) min,the average intraoperative blood loss was (192± 105) ml,and the fusion level was 4.9±0.5 on average.A total of 155 screws were inserted in the 16 patients,with a mean implant density of 98.9％±4.9％.All the patients were followed up for (26.4±3.9) months on average.The following radiographic parameters were evaluated before surgery,immediately after surgery and at the last follow-upcurve magnitude,apical vertebral translation (AVT),apical vertebral rotation (AVR),trunk shift,thoracic kyphosis (TK),thoracolumbar kyphosis (TLK),lumbar lordosis (LL) and sagittal vertical axis (SVA).The accuracy of pedicle screw placement was assessed according to postoperative CT scans.SRS-22 scores and complications were also recorded during the follow-up.Immediately after surgery,the correction rate of main lumbar curve was 80.1％±8.3％,and thoracic curve was 59.3％±8.7％,and a obvious improvement was noted in terms of AVT,AVR,trunk shift and TLK.At the last follow-up,except the increase of SVA from (-27.6± 19.5) mm to (-12.3±6.6) mm,no obvious changes of AVT,AVR,trunk shift,TK,TLK and LL were observed during the follow-up.According to CT evaluation,the satisfactory rate of pedicle screw placement was 94.2％,while the perforation rate was 5.8％ (9/155).Fusion across the facet joint were satisfactory.In SRS-22 assessment,the mean scores of functional,pain,self-image,mental state and satisfaction were (4.3 ± 0.5) points,(4.7 ± 0.6) points,(4.2 ± 0.7) points,(4.2 ± 0.5)points and (4.4 ± 0.6) points.No wound infection,implant failure and neurologic complications were found after surgery.Conclusion Wiltse approach assisted by O-arm three-dimensional CT navigation has the characteristics of small injury,less bleeding,high accuracy placement of pedicle screws and high self-satisfaction of patients.It is a feasible,safe and effective way to treat Lenke 5C AIS.