斜外侧腰椎椎间融合术引起腰椎节段性前凸改变的因素分析

Analysis of Factors Causing Segmental Lordosis Angle Changes in the Lumbar Spine during Oblique Lumbar Interbody Fusion

摘要: 目的：阐明影响斜外侧腰椎椎间融合术(oblique lumbar interbody fusion, OLIF)术后腰椎节段前凸角(segmental lordotic angle, SLA)增大或减小的相关因素。方法：对2017年至2022年9月在我院接受OLIF手术的85例患者进行回顾性分析，并进行至少1年的随访。统计患者的一般资料和围手术期数据，通过术前、术后和末次随访时获得的腰椎正侧位X线片测量椎间盘角度(disc angle, DA)、SLA、腰椎前凸角、椎间盘高度、椎间孔高度、后方间隙比(posterior gap ratio, PGR)等。根据术后SLA与术前SLA的差值 > 0和≤0分为前凸组(50例)和后凸组(35例)，用统计学方法予以分析。结果：前凸组和后凸组的PGR存在统计学差异(p < 0.05)，融合器放置在偏前位置时术后SLA增大更明显；多因素分析结果显示，PGR (B = 0.326, p = 0.000)是术后节段性前凸变化的预测因素，与SLA的变化呈正相关；术前SLA (B = −0.162, p = 0.030)也是术后节段性前凸变化的预测因素，与SLA的变化呈负相关。结论：OLIF术后导致节段前凸增大或减小与术前SLA和椎间融合器的位置有明确相关性。较小前凸的节段术后变得前凸增大，而较大前凸的节段术后前凸可能会减小。椎间融合器放置在靠前的位置上会导致节段前凸增大更明显。

Abstract: Objective: To clarify the factors that affect the increase or decrease of segmental lordotic angle (SLA) after oblique lumbar interbody fusion (OLIF) surgery. Methods: A retrospective analysis was conducted on 85 patients who underwent OLIF surgery in our hospital from 2017 to September 2022, with a minimum follow-up of 1 year. The general data and perioperative data of the patients were statistically analyzed. The disc angle (DA), SLA, lumbar lordotic angle, disc height, intervertebral foramen height, and posterior gap ratio (PGR) were measured by pre-operative, post-operative, and final follow-up lumbar lateral X-rays. Based on the difference between postoperative SLA and preoperative SLA being >0 and ≤0, patients were divided into a lordotic group (50 cases) and a kyphotic group (35 cases). Statistical analysis was performed using statistical methods. Results: There was a statistically significant difference in PGR between the lordotic group and the kyphotic group (p < 0.05). The post-operative SLA increased more significantly when the fusion device was placed in a more anterior position. Multivariate analysis showed that PGR (B = 0.326, p = 0.000) was a predictor of segmental lordotic change after surgery, which was positively correlated with the change in SLA. Preoperative SLA (B = −0.162, p = 0.030) was also a predictor of segmental lordotic change after surgery, which was negatively correlated with the change in SLA. Conclusion: The increase or decrease of segmental lordosis after OLIF surgery is clearly correlated with pre-operative SLA and the position of the interbody fusion device. The segment with smaller pre-operative lordosis became more lordotic after surgery, while the segment with larger pre-operative lordosis may have a decrease in pre-operative lordosis. Placing the interbody fusion device in a more anterior position results in a more pronounced increase in segmental lordosis.