Solla Federico, Barrey Cédric Y, Burger Evalina, Kleck Christopher J, Fière Vincent
Orthopaedic and Scoliosis Surgery Unit, Lenval Hospital, Nice.
Spine Unit, P. Wertheimer Hospital, University Hospitals of Lyon, Bron.
Clin Spine Surg. 2019 Mar;32(2):80-86. doi: 10.1097/BSD.0000000000000721.
This was an innovative concept and a preliminary prospective series.
The aim of this study was to present the concept and the technical aspects of patient-specific rods (PSR), and compare preoperative and postoperative sagittal parameters (after PSR implantation), with a special focus on the difference pelvic incidence (PI)-lumbar lordosis (LL).
Despite established techniques for planning and proven correlations between quality of life and sagittal alignment, some patients do not achieve optimal radiologic outcomes after surgery and are still hypolordotic and imbalanced. We hypothesize that the use of PSR could improve the correspondence between planning and surgical realization.
The planning was based on spinopelvic parameters evaluated on a full-spine x-ray. The surgical procedure including osteotomies was simulated using a dedicated program to reach the following objectives: PI-LL<10 degrees, a pelvic tilt <20 degrees, and sagittal vertical axis <50 mm. From the virtually corrected spine, the rod curvature and length were defined. Two PSRs were thus precisely manufactured and bent to this specification. Adults with degenerative spinal disorders requiring a construct ≥5 levels were implanted with PSR and prospectively included. We compared ratios through the χ test.
A total of 60 patients (mean age of 64.4 years old; range, 34-83) were included. Follow-up was carried out over a period of 1 year. Average pedicle screws construct was of 6.4 levels (range, 5-9). Eight patients underwent a pedicle subtraction osteotomy. PI-LL was <10 degrees at baseline in 29/60 patients, and at follow-up in 50/60 (odds ratio=5, P=E-5).
The ratio of patients with optimal PI-LL improved significantly from PSR implantation. In comparison with published data for conventional surgery, patients implanted with PSR were 2.6 times more likely to be optimally corrected. The expected benefits of PSR include the optimal execution of the plan, decreased mechanical complications, and reduced operating time, no longer requiring the bending of rods during surgery. A randomized trial on sagittal correction using PSR is ongoing.
这是一个创新概念及初步前瞻性系列研究。
本研究旨在介绍定制棒（PSR）的概念及技术方面，并比较术前和术后矢状面参数（PSR植入后），特别关注骨盆入射角（PI）-腰椎前凸（LL）的差异。
尽管已有规划技术且生活质量与矢状面排列之间存在已证实的相关性，但一些患者术后并未获得最佳的影像学结果，仍存在腰椎前凸不足和失衡。我们假设使用PSR可改善规划与手术实施之间的契合度。
规划基于全脊柱X线片评估的脊柱骨盆参数。使用专用程序模拟包括截骨术在内的手术过程，以达到以下目标：PI-LL<10度、骨盆倾斜<20度以及矢状垂直轴<50毫米。根据虚拟矫正后的脊柱确定棒的曲率和长度。据此精确制造并弯曲两根PSR。纳入前瞻性研究的患者为患有退行性脊柱疾病且需要≥5节段内固定的成年人，并植入PSR。我们通过χ检验比较比率。
共纳入60例患者（平均年龄64.4岁；范围34-83岁）。随访1年。平均椎弓根螺钉内固定节段为6.4节（范围5-9节）。8例患者接受了椎弓根截骨术。29/60例患者基线时PI-LL<10度，随访时50/60例患者如此（优势比=5，P=E-5）。
植入PSR后，PI-LL最佳的患者比例显著提高。与传统手术的已发表数据相比，植入PSR的患者获得最佳矫正的可能性高出2.6倍。PSR的预期益处包括计划的最佳实施、机械并发症减少、手术时间缩短，术中不再需要弯曲棒。一项关于使用PSR进行矢状面矫正的随机试验正在进行中。
