融合器前置或中后置对改良侧方入路腰椎椎体间融合术患者邻近关节退变的影响

The effects of anterior placement or middle-posterior placement of fusion cage on adjacent segment degeneration of patients undergoing CLIF

目的探讨融合器放置位置对改良侧方入路腰椎椎体间融合术(CLIF)后邻近节段退变的影响。方法46例行CLIF的腰椎退行性病变患者,根据术中融合器放置位置分为前置组(n=22)和中后置组(n=24),CLIF术中融合器中心位于椎间隙前1/3部为前置组,CLIF术中融合器中心位于椎间隙中后2/3部为中后置组。比较两组手术前、后疼痛视觉模拟评分(VAS)和Oswestry功能障碍指数(ODI);比较两组术前和末次随访时相邻椎间隙高度、相邻椎体间椎间活动度;比较两组相邻椎体椎间盘改良Pfirrmann分级改变。结果两组术后各时间点VAS评分和ODI比较,差异无统计学意义(P>0.05);末次随访时两组间椎间隙高度比较及与术前比较差异无统计学意义(P>0.05),两组L3-4椎间活动度高于术前,且中后置组高于前置组(P<0.05),两组L5S1椎间活动度手术前后比较,差异无统计学意义(P>0.05);前置组3例Pfirrmann等级升高1级,中后置组6例升高1级,1例升高2级。前置组影像学邻近节段退变(ASD)发生率13.64%,中后置组发生率为29.17%,差异无统计学意义(P>0.05)。结论CLIF术能有效改善腰椎管狭窄症临床症状和恢复腰椎功能,融合器放置位置对短期疗效无明显影响,融合器位置中后置相较于前置会更显著地影响术后邻近节段椎间活动度。

Objective To investigate the effects of fusion cage placement locations on adjacent segment degeneration(ASD)after modified crenel lateral interbody fusion(CLIF).Methods A retrospective analysis was performed on 46 patients with lumbar degenerative lesions who underwent CLIF.They were divided into anterior placement group(n=22)and middle-posterior placement group(n=24)according to intraoperative placement locations of fusion cage.In CLIF,fusion cage was located at anterior 1/3 of intervertebral space was defined as anterior placement group,while located at middle-posterior 2/3 was defined as middle-posterior placement group.The score of visual analogue scale(VAS)and Oswestry dysfunction index(ODI)before and after surgery were compared between the two groups.The height of adjacent intervertebral space and adjacent intervertebral activity before surgery and at the end of last follow-up were compared between the two groups.The changes in modified Pfirrmann grading of adjacent intervertebral disc were also compared between the two groups.Results There was no significant difference in VAS score and ODI between the two groups at any time point after surgery(P>0.05).There was no significant difference in height of intervertebral space between the two groups at the end of last follow-up(P>0.05).After surgery,intervertebral activity of L3-4 in the two groups was increased,and the above index in the middle-posterior placement group was higher than that in the anterior placement group(P<0.05).There was no significant difference between the two groups in L5S1 intervertebral activity before and after surgery(P>0.05).In the anterior placement group,there were 3 cases with Pfirrmann grade increasing by 1 level.In middle-posterior placement group,there were 6 cases increasing by 1 level,and 1 case increasing by 2 levels.The incidence ASD in the anterior placement group and the middle-posterior placement group were 13.64%and 29.17%,respectively(P>0.05).Conclusion CLIF can effectively improve the clinical symptoms such as lumbar spinal stenosis and restore lumbar function.There is no significant effect of fusion cage placement locations on short-term curative effect.The middle-posterior placement of fusion cage will more significantly influence intervertebral activity of adjacent segments when compared with anterior placement.