Chen Qian, Ai Youwei, Huang Yong, Li Qiujiang, Wang Juehan, Ding Hong, Zhu Ce, Feng Ganjun, Liu Limin
Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, No.37 Guoxue alley, Chengdu 610041, Sichuan, China; Department of Orthopaedics and Laboratory of Biological Tissue, Engineering and Digital Medicine, Affiliated Hospital of North Sichuan Medical College, No. 1 South Maoyuan Road, Nanchong 637000, Sichuan, China.
Department of Orthopedic Surgery and Orthopedic Research Institute, West China Hospital, Sichuan University, No.37 Guoxue alley, Chengdu 610041, Sichuan, China.
Spine J. 2023 Nov;23(11):1652-1658. doi: 10.1016/j.spinee.2023.07.002. Epub 2023 Jul 11.
Cage subsidence following transforaminal lumbar interbody fusion (TLIF) has closely correlated with poor vertebral bone quality. Studies have shown better predictive value for cage subsidence by measuring bone density at specific site. However, few studies have been performed to examine the relationship between site-specific MRI bone assessment and cage subsidence in patients who have undergone lumbar interbody fusion. The association between MRI-based assessment of endplate bone quality and cage subsidence after TLIF remains unclear.
To study the predictive value of MRI-based endplate bone quality (EBQ) score for cage subsidence following TLIF, using QCT bone densitometry as a reference standard.
STUDY DESIGN/SETTING: A retrospective study.
A total of 280 adult patients undergoing single-segment TLIF for degenerative lumbar spine disease from 2010 to 2020 at our institution who had preoperative T1-weighted MRIs.
Cage subsidence, disc height, endplate bone quality (EBQ) score, bone mineral density, fusion rate.
The retrospective study reviewed patients who underwent TLIF at one institution between March 2010 and October 2020. Cage subsidence was measured with postoperative lumbar X-rays based on the cage protrusion through into the superior or inferior end plate or both by more than 2 mm. The EBQ score was measured from preoperative T1-weighted MRI in accordance with the previously reported method.
Cage subsidence was observed in 42 of the 280 patients. Bone densitometry with quantitative computed tomography was visibly reduced in the subsidence group. The mean EBQ scores of the lumbar endplate bone was 4.3±0.9 in nonsubsidence and 5.0±0.6 in subsidence. On multivariate logistic regression, the difference between the two groups was remarkable. Risk of cage subsidence increases significantly with higher EBQ scores (odds ratio [OR]=2.063, 95% confidence interval [CI] 1.365-3.120, p=.001) and was an independent factor in predicting subsidence after TLIF. On receiver operating characteristic curve, the AUC for the EBQ score was 0.820 (95% confidence interval [CI]: 0.755-0.844) and the most suitable threshold for the EBQ score was 4.730 (sensitivity: 76.2%, specificity: 83.2%).
Higher EBQ scores measured on preoperative MRI correlated significantly with cage subsidence following TLIF. Performing EBQ assessment prior to TLIF may be a valid method of predicting the risk of postoperative subsidence.
经椎间孔腰椎椎体间融合术（TLIF）后椎间融合器下沉与椎体骨质质量差密切相关。研究表明，通过测量特定部位的骨密度对椎间融合器下沉具有更好的预测价值。然而，很少有研究探讨腰椎椎体间融合术后特定部位MRI骨评估与椎间融合器下沉之间的关系。基于MRI的终板骨质质量评估与TLIF术后椎间融合器下沉之间的关联仍不明确。
以定量CT骨密度测定作为参考标准，研究基于MRI的终板骨质质量（EBQ）评分对TLIF术后椎间融合器下沉的预测价值。
研究设计/地点：一项回顾性研究。
2010年至2020年在本机构接受单节段TLIF治疗退行性腰椎疾病且术前行T1加权MRI检查的280例成年患者。
椎间融合器下沉、椎间盘高度、终板骨质质量（EBQ）评分、骨密度、融合率。
这项回顾性研究纳入了2010年3月至2020年10月期间在一家机构接受TLIF手术的患者。根据术后腰椎X线片测量椎间融合器下沉情况，即椎间融合器向上或向下终板或两者均突出超过2mm。按照先前报道的方法从术前行T1加权MRI测量EBQ评分。
280例患者中有42例观察到椎间融合器下沉。下沉组定量CT骨密度明显降低。非下沉组腰椎终板骨的平均EBQ评分为4.3±0.9，下沉组为5.0±0.6。多因素逻辑回归分析显示，两组间差异显著。EBQ评分越高，椎间融合器下沉风险显著增加（比值比[OR]=2.063，95%置信区间[CI] 1.365-3.120，p=0.001），是预测TLIF术后下沉的独立因素。在受试者工作特征曲线上，EBQ评分的曲线下面积（AUC）为0.820（95%置信区间[CI]：0.755-0.844），EBQ评分最合适的阈值为4.730（敏感性：76.2%，特异性：83.2%）。
术前MRI测量的较高EBQ评分与TLIF术后椎间融合器下沉显著相关。在TLIF术前进行EBQ评估可能是预测术后下沉风险的有效方法。
