腰椎管狭窄症行后路椎间融合术前、术后邻近节段退变影像学的研究

Influence of preoperative adjacent segment degeneration on the efficacy of posterior interbody fusion in patients with lumbar spinal stenosis

目的探讨腰椎管狭窄症(lumbar spinal stenosis,LSS)患者行后路椎体间融合手术前后邻近节段退变(adjacent segment degeneration,ASD)影像学的特征。方法纳入2017年3月~2019年3月行后路腰椎减压固定融合术治疗的LSS患者121例,依据患者术前邻近节段的退变情况分为:A组68例,术前邻近节段无退变;B组53例,术前邻近节段存在退变。对两组患者随访2年以上,对比其术前和末次随访的腰痛、下肢痛的VAS评分、日本骨科学会JOA评分和Oswestry功能障碍指数(Oswestry disability index,ODI);同时,对两组患者术后ASD的发生情况进行比较;对术后ASD的潜在风险因素进行多因素Logistic回归分析。结果两组患者术后均获24~31个月的随访,平均27.3个月。B组术后ASD的发生率显著高于A组(62.3%vs 20.6%,P<0.05)。术前存在退变和体质量指数均为患者术后发生ASD的独立风险因素(P<0.05)。A、B两组患者术后ASD退变的影像表现均以椎管狭窄为主,分别占比9/14和24/33;而椎间盘退变Pfirrmann分级在末次随访时并未有明显加重。A、B组患者末次随访时的VAS评分、JOA评分和ODI指数均获显著改善(P<0.05),但A组JOA评分高于B组(P<0.05);B组患者中,ASD亚组在末次随访时的腰痛VAS评分和ODI指数均高于无ASD亚组(P<0.05)。结论术前邻近节段退变和体质量指数均是LSS患者行腰椎减压融合手术后发生ASD的独立风险因素;术后椎管狭窄是ASD的主要影像改变。

Objective To explore the imaging characteristics of adjacent segment degeneration(ASD)before and after posterior interbody fusion in patients with lumbar spinal stenosis(LSS).Methods A total of 121 patients with LSS who underwent posterior lumbar decompression and fusion from March 2017 to March 2019 were analyzed.According to the degeneration of adjacent segments,they were divided into group A and group B:68 patients in group A had no degeneration of adjacent segments before operation;53 patients in group B had degeneration of adjacent segments before operation.The patients in the two groups were followed up for more than 2 years,and the VAS scale,Japanese Orthopedic Association(JOA)score and Oswestry disability index(ODI)of low back pain and lower limb pain were compared before and at the last follow-up.Meanwhile,the incidence of postoperative ASD in the two groups was compared,and the potential risk factors of postoperative ASD were analyzed by multivariate logistic regression analysis.Results Both two groups were followed up for 24 to 31 months,with an average follow-up period of 27.3 months.The incidence rate of postoperative ASD in group B was significantly higher than that in group A(62.3%vs 20.6%,P<0.05).Logistic regression analysis confirmed that preoperative degeneration and body mass index were independent risk factors for postoperative ASD(P<0.05).The imaging characteristic of ASD degeneration in group A and group B was spinal stenosis,accounted for 9/14 and 24/33 respectively,while Pfirrmann grade of intervertebral disc degeneration did not increase significantly at the last follow-up.The VAS score,JOA score and ODI index of group A and group B at the last follow-up were significantly improved(P<0.05),but the JOA score of group A was higher than that of group B(P<0.05).In group B,the VAS score and ODI index of low back pain of ASD subgroup at the last follow-up were higher than those of non-ASD subgroup(P<0.05).Conclusion Preoperative adjacent segment degeneration and body mass index are independent risk factors for ASD after lumbar decompression and fusion in patients with LSS;postoperative spinal stenosis is the main imaging change of ASD.