Objective: To investigate the effects of Modic changes on the fusion rate and cage subsidence after transforaminal lumbar interbody fusion (TLIF). Methods: From January 2015 to January 2018, a total of 186 patients with degenerative lumbar disease who received lumbar instrumentation fusion and monosegmental TLIF with single polyetheretherketone (PEEK) cage in Nanjing Drum Tower Hospital were retrospectively reviewed. Patients with Modic changes at the level where the cage was placed were enrolled as Modic group, and the remaining were assigned into non-Modic group. Disk height, lumbar lordosis and segmental lordosis of the level with TLIF were measured based on the preoperative, postoperative and latest follow-up lateral radiograph. The fusion rate and cage subsidence (more than 2 mm on either endplate) were recorded based on CT scan at the latest follow-up. The Oswestry disability index (ODI) and visual analogue scale (VAS) of pain was used to evaluate the clinical outcome. The data were compared with paired t test between the two groups. Results: In this study, there were 70 males and 116 females with an average age of (55±13) years. There were 99 patients in the Modic group (25 with type 1, 66 with type 2, 8 with type 3), and 87 patients in the non-Modic group. There was no significant difference between Modic group and non-Modic group in demographics and postoperative radiographs. The patients were followed-up for (19±4) months (13 to 48 months). All patients achieved grade 1 or 2 fusion. Cage subsidence was detected in 34 patients (18.3%, 34/186). The incidence of subsidence in Modic group (24.2%, 24/99) was significantly higher than that in non-Modic group (11.5%, 10/87) (χ(2)=5.038, P<0.05), and the incidence of subsidence in type Ⅰ (28.0%, 7/25) and type Ⅱ (24.2%, 16/66) were higher than that in non-Modic group (11.5%, 10/87). There was no significant difference in ODI and VAS between Modic group and non-Modic group before and after the operation and at the latest follow-up (t=0.397-1.568, all P>0.05). Conclusion: Preoperative Modic changes have no impact on fusion rate after transforaminal lumbar interbody fusion, but both type Ⅰ and Ⅱ Modic changes do increase the risk of cage subsidence.
目的： 探讨Modic改变对于经椎间孔腰椎椎间融合术（TLIF）术后椎间融合效果和融合器沉降的影响。 方法： 回顾性分析186例于2015年1月至2018年1月在南京鼓楼医院放置单枚高分子聚醚醚酮（PEEK）融合器行单节段TLIF手术患者的临床资料，根据术前MRI影像放置融合器节段是否存在Modic改变，将患者分为Modic改变组和无Modic改变组，于X线片上测量术前、术后及末次随访时行TLIF节段的椎间隙高度、腰椎前凸角和融合器节段前凸角，于末次随访的CT上观察融合情况和融合器沉降。使用Oswestry功能障碍指数（ODI）、腰腿痛视觉模拟评分（VAS）评价临床疗效。各组不同时间数据比较采用配对t检验。 结果： 全组患者中男70例，女116例，平均年龄（55±13）岁。Modic改变组99例，Ⅰ型25例，Ⅱ型66例，Ⅲ型8例；无Modic改变组87例。两组患者在年龄、性别、诊断、手术时间、手术出血量、融合节段数、随访时间及术后影像学参数等差异均无统计学意义。术后平均随访（19±4）个月（13~48个月），两组所有放置融合器节段均达到1级或2级融合。34例（18.3%，34/186）观察到融合器沉降。Modic改变组融合器沉降发生率（24.2%，24/99）高于无Modic改变组（11.5%，10/87），差异有统计学意义（χ(2)=5.038，P<0.05），其中Ⅰ型（28.0%，7/25）和Ⅱ型（24.2%，16/66）明显高于无Modic改变组（11.5%，10/87）。术前、术后及末次随访时Modic改变组与无Modic改变组VAS评分及ODI的差异均无统计学意义（t=0.397~1.568，均P>0.05）。 结论： 术前Modic改变对于TLIF术后椎间融合效果没有明显影响，但可显著增加融合器沉降风险，尤以Modic Ⅰ型和Ⅱ型为著。.
Keywords: Cage subsidence; Lumar interbody fusion; Modic changes.