单节段颈前路椎间融合术后ROI-C融合器沉降的相关因素分析

Risk factors for postoperative subsidence of ROI-C in single-level anterior cervical discectomy and fusion

中文关键词:  颈前路椎间盘切除减压融合术  椎间融合器  沉降  颈椎曲度

英文关键词:Anterior cervical discectomy and fusion  Stand-alone cage  Postoperative subsidence  Cervical alignment

中文摘要:

  【摘要】 目的：分析采用ROI-C行颈前路单节段椎间盘切除减压融合（anterior cervical discectomy and fusion，ACDF）术后融合器沉降的相关因素。方法：回顾总结采用ROI-C行单节段ACDF治疗颈椎间盘退变性疾病的83例患者资料。记录患者年龄、性别、手术节段、吸烟史及骨密度检查结果。在术前颈椎侧位X线片上测量颈椎整体曲度（cervical alignment，CA）、融合节段角度（segmental angle，SA）、椎间隙前高度（anterior disc height，ADH）和椎间隙后高度（posterior disc height，PDH）。将随访的中立位颈椎侧位X线片与术后即刻比较，ADH或PDH丢失＞2mm判定为融合器沉降，分入沉降（subsidence）组（S组，22例），并记录沉降的部位；≤2mm分入未沉降（nonsubsidence）组（N组，61例）。应用独立样本t检验、χ2检验对以上参数行组间比较，采用多变量Logistic回归分析单节段ACDF术后ROI-C沉降的危险因素。将危险因素进一步分组使用χ2检验计算似然比（likelihood ratio，LR）进行评价。结果：单节段ACDF术后ROI-C沉降发生率为26.5%（22/83），其中陷入椎体前方终板者占63.6%（14/22）。S组、N组年龄分别为59.86±12.11岁、52.77±10.34岁，差异有统计学意义（P=0.010）；性别、吸烟史、手术节段和骨密度均无统计学差异（P>0.05）。S组术前的CA、SA、ADH分别为-0.800°±5.637°、0.432°±2.162°和3.768±1.210mm，N组分别为4.893°±5.718°、1.198°±1.826°和5.066±1.257mm，两组比较差异有统计学意义（P<0.001，P=0.031和P<0.001），两组的PDH差异无统计学意义（P=0.092）。多变量Logistic回归分析显示术前CA和年龄是ROI-C沉降的危险因素（P=0.014和P=0.038）。根据术前CA情况将患者分为术前CA后凸（CA＜0°）和前凸（CA≥0°）组，根据术前年龄将患者分为＜60岁和≥60岁组，χ2检验显示术前CA后凸和60岁以上病例ROI-C沉降概率分别比前凸和60岁以下病例高12.5倍和4.5倍（LR=12.529，P<0.001；LR=4.454，P=0.030）。结论：术前CA后凸和年龄60岁以上是单节段ACDF术后ROI-C沉降的危险因素。选择ROI-C行单节段ACDF治疗颈椎间盘退变性疾病时应考虑这两项因素的影响。

英文摘要:

  【Abstract】 Objectives: To investigate and analyze the risk factors for postoperative subsidence of RIO-C in single-level anterior cervical discectomy and fusion(ACDF). Methods: Eighty-three patients who underwent single-level ACDF with ROI-C for cervical degenerative disc disease were included in this retrospective study. The factors such as age, sex, operative level, smoking history, bone mineral density(BMD), and preoperative sagittal cervical alignment(CA), operated segmental angle(SA), anterior/posterior disc height(ADH/PDH) in the lateral radiographs of cervical spine were collected. Patients were categorized into subsidence group(S group, n=22) and nonsubsidence group(N group, n=61) based on the loss of the disc height for 2mm. These clinical and radiographic factors were compared between two groups by using independent sample t-test or Chi-square test． Risk factors for postoperative subsidence of ROI-C in single-level ACDF were analyzed by multivariate Logistic regression. The likelihood ratios(LR) of risk factors were obtained by using χ2 test on the basis of a cutoff. Results: Subsidence occurred in 22(26.5%) of 83 patients. The incidence of subsidence into the anterior endplate was 63.6%(14/22). Mean age was 59.86±12.11 and 52.77±10.34 years(P=0.010) in group S and group N, while gender, surgery level, smoking history, BMD showed no significant differences between group S and group N(P>0.05). A significant difference was found with respect to preoperative CA, SA and ADH in group S compared with group N(P<0.001, P=0.031 and P<0.001, respectively), whereas there was no significant difference in PDH(P=0.092). Multivariate Logistic regression analysis revealed that the preoperative CA(P=0.014) and age(P=0.038) affected subsidence. The patients in each group were assigned to kyphotic or lordotic subgroup and senior or junior subgroup according to cervical alignment cutoff of 0 degree and age cutoff of 60 years respectively. The risk of ROI-C subsidence in the kyphotic subgroup was 12.5-fold greater than that in the lordotic subgroup(LR=12.529, P<0.001). The patients older than 60 years were 4.5-fold more likely to display subsidence than those younger than 60 years(LR=4.454, P=0.030). Conclusions: In single-level ACDF with ROI-C, the risk factors affecting postoperative cage subsidence are preoperative CA of kyphosis and age older than 60 years. The data suggest that spinal surgeons should cautiously consider the preoperative CA and/or age when deciding on the ROI-C for single-level ACDF to treat patients with degenerative disc disease.