本研究的目的是 1) 确定经椎间孔腰椎椎间融合术 (TLIF) 椎体下沉的发生率； 2) 使用基于 CT 的评估确定术前和术中患者和器械特定风险因素预测术后下沉的相对重要性； 3) 确定 TLIF 下沉对术后并发症和融合率的影响。 回顾性识别 2017 年至 2019 年间在多机构学术中心因腰椎退变性疾病接受一级或两级 TLIF 的所有成年患者。排除外伤、感染、恶性肿瘤、既往指数水平融合、前后路联合手术、TLIF 水平超过两个水平的手术或不完整随访的患者。在术后 6 个月以上获得的冠状和矢状 CT 扫描的面向终板的表面上直接测量每个 TLIF 水平的上终板和下终板的椎间沉降。根据每个手术水平的最大下沉量对患者进行分组，根据先前记录的 < 2 毫米、2 至 4 毫米和 ≥ 4 毫米阈值分别分为轻度、中度或重度。单变量和回归分析比较了患者的人口统计数据、合并症、术前骨质量、手术因素（包括椎间融合器参数）以及各沉降组的融合和并发症发生率。共有 67 名患者（具有 85 个独特的融合水平）符合纳入和排除标准。总体而言，TLIF 后，28% 的水平表现出中度下沉，35% 的水平表现出严重下沉，上终板下沉和下终板下沉没有显着差异。中度（≥ 2 毫米）和重度（≥ 4 毫米）沉降与融合器表面积和泰拉德指数以及采用聚醚醚酮 (PEEK) 材料和锯齿表面几何形状的椎间融合器的减少显着相关。严重下沉还与术前椎间盘间隙较高、椎体亨斯菲尔德单位 (HU) 减少、骨形态发生蛋白 (BMP) 缺乏以及融合器表面光滑显着相关。回归分析显示，Taillard 指数、笼表面积和 HU 均有所下降，并且没有使用 BMP 来预测沉降。严重下沉被发现是假关节的预测因素，但与翻修手术没有显着相关性。TLIF 下沉的患者水平危险因素包括 HU 降低和术前椎间盘高度增加。术中 TLIF 下沉的危险因素包括融合器表面积减少、PEEK 融合器材料、子弹笼、后融合器定位、光滑的融合器表面和锯齿形表面设计。严重下沉预示着TLIF假关节；然而，这种关系的因果关系仍不清楚。

The aims of this study were to 1) define the incidence of transforaminal lumbar interbody fusion (TLIF) interbody subsidence; 2) determine the relative importance of preoperative and intraoperative patient- and instrumentation-specific risk factors predictive of postoperative subsidence using CT-based assessment; and 3) determine the impact of TLIF subsidence on postoperative complications and fusion rates.All adult patients who underwent one- or two-level TLIF for lumbar degenerative conditions at a multi-institutional academic center between 2017 and 2019 were retrospectively identified. Patients with traumatic injury, infection, malignancy, previous fusion at the index level, combined anterior-posterior procedures, surgery with greater than two TLIF levels, or incomplete follow-up were excluded. Interbody subsidence at the superior and inferior endplates of each TLIF level was directly measured on the endplate-facing surface of both coronal and sagittal CT scans obtained greater than 6 months postoperatively. Patients were grouped based on the maximum subsidence at each operative level classified as mild, moderate, or severe based on previously documented < 2-mm, 2- to 4-mm, and ≥ 4-mm thresholds, respectively. Univariate and regression analyses compared patient demographics, medical comorbidities, preoperative bone quality, surgical factors including interbody cage parameters, and fusion and complication rates across subsidence groups.A total of 67 patients with 85 unique fusion levels met the inclusion and exclusion criteria. Overall, 28% of levels exhibited moderate subsidence and 35% showed severe subsidence after TLIF with no significant difference in the superior and inferior endplate subsidence. Moderate (≥ 2-mm) and severe (≥ 4-mm) subsidence were significantly associated with decreases in cage surface area and Taillard index as well as interbody cages with polyetheretherketone (PEEK) material and sawtooth surface geometry. Severe subsidence was also significantly associated with taller preoperative disc spaces, decreased vertebral Hounsfield units (HU), the absence of bone morphogenetic protein (BMP) use, and smooth cage surfaces. Regression analysis revealed decreases in Taillard index, cage surface area, and HU, and the absence of BMP use predicted subsidence. Severe subsidence was found to be a predictor of pseudarthrosis but was not significantly associated with revision surgery.Patient-level risk factors for TLIF subsidence included decreased HU and increased preoperative disc height. Intraoperative risk factors for TLIF subsidence were decreased cage surface area, PEEK cage material, bullet cages, posterior cage positioning, smooth cage surfaces, and sawtooth surface designs. Severe subsidence predicted TLIF pseudarthrosis; however, the causality of this relationship remains unclear.