Lertudomphonwanit Thamrong, Berry Chirag A, Jain Viral V, Sturm Peter F
Department of Orthopaedics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
Cincinnati VA Medical Center, Cincinnati, OH, USA.
Asian Spine J. 2022 Jun;16(3):375-385. doi: 10.31616/asj.2020.0398. Epub 2021 May 10.
Retrospective cohort study.
To determine whether implant density impact three-dimensional deformity correction in posterior spinal fusion (PSF) without Ponte osteotomies (POs) for patients with Lenke 1 and 2 adolescent idiopathic scoliosis (AIS).
Currently, the optimal pedicle screw (PS) density for flexible moderate-sized thoracic AIS curve correction is still controversial. There are limited data regarding the impact of implant density on three-dimensional correction in PSF without the use of PO for thoracic AIS surgery.
A database of patients with AIS with Lenke 1 and 2 curves treated with PSF without PO and instrumented with PSs and ≥2-year follow-up was reviewed. The preoperative, immediate, and final follow-up postoperative radiographs were analyzed. The correlation between PS density and the following factors were determined: major curve correction (MCC), correction index (CI; MCC/curve flexibility), kyphosis angle change, and rib index (RI) correction. Then, patients were divided into low-density (LD) and high-density (HD) groups according to mean PS density for the entire cohort (1.5 PS per level). Demographics and radiographic and clinical outcomes were compared between groups.
The study included 99 patients with Lenke 1 and 23 patients with Lenke 2 AIS. The average MCC was 67.2%. There was no correlation between screw density and these parameters: MCC (r=0.10, p=0.26), CI (r=0.16, p=0.07), change in T2-T12 kyphosis angle (r=-0.13, p=0.14), and RI correction (r=-0.09, p=0.37). Demographic and preoperative radiographic parameters were similar between the LD and HD groups. At the latest follow-up, there were no differences between the two groups in regard to MCC, CI, change in T2-T12 kyphosis angle, RI correction, and Scoliosis Research Society-30 scores (all p>0.05).
This study revealed no significant correlation between screw density and curve correction in any planes. HD construct may not provide better deformity correction in patients with flexible and moderate thoracic AIS undergoing PSF without PO.
回顾性队列研究。
确定对于Lenke 1型和2型青少年特发性脊柱侧凸（AIS）患者，在不进行庞特截骨术（PO）的后路脊柱融合术（PSF）中，植入物密度是否会影响三维畸形矫正。
目前，对于柔韧性中等大小的胸椎AIS曲线矫正，最佳椎弓根螺钉（PS）密度仍存在争议。关于在胸椎AIS手术中不使用PO的PSF中植入物密度对三维矫正的影响的数据有限。
回顾了一个数据库，该数据库包含接受了不进行PO且使用PS进行器械固定并随访≥2年的Lenke 1型和2型AIS患者。分析术前、即刻及最终随访时的术后X线片。确定PS密度与以下因素之间的相关性：主弯矫正（MCC）、矫正指数（CI；MCC/曲线柔韧性）、后凸角变化及肋骨指数（RI）矫正。然后，根据整个队列的平均PS密度（每节段1.5枚PS）将患者分为低密度（LD）组和高密度（HD）组。比较两组之间的人口统计学、影像学和临床结果。
该研究纳入了99例Lenke 1型患者和23例Lenke 2型AIS患者。平均MCC为67.2%。螺钉密度与这些参数之间无相关性：MCC（r = 0.10，p = 0.26）、CI（r = ¼ 0.16，p = 0.07）、T2 - T12后凸角变化（r = -0.13, p = 0.14）及RI矫正（r = -0.09，p = 0.37）。LD组和HD组的人口统计学和术前影像学参数相似。在最近一次随访时，两组在MCC, CI, T2 - T12后凸角变化、RI矫正及脊柱侧凸研究学会-30评分方面均无差异（所有p > 0.05）。
本研究表明，螺钉密度与任何平面的曲线矫正之间均无显著相关性。对于接受不进行PO的PSF的柔韧性中等的胸椎AIS患者，高密度结构可能无法提供更好的畸形矫正效果。
