摘要目的 探讨单节段融合节段上位相邻椎间盘存在轻中度退变时,Topping-off手术预防相邻节段退变加重的作用.方法 回顾性分析2008年4月至2010年3月所有行L5～S1腰椎后路减压椎间融合术(PLIF)+L4～5棘突间固定(ISP)置入术的患者资料(Topping-off组)；回顾同期所有行L5～S1 PLIF的患者资料(PLIF组).两组患者术前性别、年龄、体质量指数、术前椎间盘分级均匹配.患者于术前及末次随访时进行视觉模拟评分(VAS)和日本骨科学会腰椎功能评分(JOA).对患者术前及术后随访时的X线片进行测量.结果 Topping-off组及PLIF组分别有25及42例患者资料完整.随访时间平均为24.8及23.7个月.两组患者均未出现症状学相邻节段退变.Topping-off组手术时间为(120±24)min,PLIF组为(106±21)min.两组术中出血量及术后引流量差异无统计学意义(P＞0.05).两组术后随访与术前相比,VAS、腰椎JOA评分较术前均有显著改善(P＜0.01)；侧位片L4～5椎间隙前后缘高度变化均无统计学意义(P＞0.05)；L4～5椎间隙角及腰椎前凸角均显著增大(Topping-off组:t=-2.30和-2.24,P＜0.05；PLIF组:t=-2.76和-1.83,P＜0.05).动力位X线片Topping-off组L4～5节段腰椎向前活动角度及L4椎体向前滑移距离变化无统计学意义(P＞0.05),L4～5节段过伸位活动角度及L4椎体后缘向后活动距离明显减小(t=5.83和4.92,P＜0.01).PLIF组L4～5节段过屈及过伸位活动角度(t=-7.82和-4.90,P＜0.01)及L4椎体前后滑移距离(t=-15.67和-18.58,P＜0.01)均明显增大.结论 当单节段融合节段上位相邻椎间盘存在轻中度退变时,Topping-off术式与单节段PLIF术式中短期疗效及安全性相近,Topping-off术式可限制过伸位时相邻节段活动,并可防止上位腰椎前后过度移动,具有潜在的预防相邻节段退变的作用.

abstractsObjective To investigate the early-middle stage clinical results of Topping-off surgery in preventing adjacent segment degeneration when mild or moderate adjacent segment degeneration exists before surgery.Methods All the cases that received L5-S1 posterior lumbar interbody fusion(PLIF)+ L4-L5interspinous process(ISP)surgeries between April 2008 and March 2010(Topping-off group)were analyzed retrospectively.The cases received L5-S1 PLIF surgery and whose intervertebral disc degeneration using modified Pfirrmann's grading system were grade 4-6 were analyzed retrospectively at the same time(PLIFgroup).Both groups matched in gender,age,body mass index and Pfirrmann's grading of disc.All the patients were evaluated with visual analogue scale(VAS)and Japanese orthopaedic association(JOA)scores before the surgery and in the last follow-up.The X-ray films before and after surgery were measured.Results There were 25 patients in Topping-off group and 42 patients in PLIF group were included in the final analysis.The follow-up averaged 24.8 and 23.7 months.No symptomatic or radiological adjacent segment degeneration was observed.The average surgery time was(120 ± 24)min and(106 ± 21)min.There was no significant difference in the blood loss during surgery or post-operation drainage(P ＞ 0.05).VAS and lumbar JOA score improved in both groups(P ＜ 0.01).In the lateral view of lumbar spine,neither of anterior or posterior disk height was significantly changed(P ＞ 0.05),segmental lordosis of L4-L5,total lordosis were all increased(Topping-off group:t =-2.30 and-2.24,P ＜ 0.05 ; PLIF group:t =-2.76 and -1.83,P ＜ 0.05).In the hyperextension and hyperflexion view,Topping-off group' s range of motion (ROM)and olisthesis in the L4-5 segment did not significantly change in flexion(P ＞0.05),but decreased in extension(t =5.83 and 4.92,P ＜0.01).In PLIF group,the ROM(t =-7.82 and-4.90,P ＜0.01)and olisthesis(t =-15.67 and-18.55,P ＜ 0.01)both significantly increased in extension and flection.Conclusions Compared with single segmental PLIF surgery,Topping-off surgery can achieve similar symptomatic improvement in cases with pre-existing mild or moderate adjacent segment degeneration,restrict the adjacent segment's range of motion in extension and prevent excessive olisthesis of adjacent segment in both extension and flexion.Topping-off surgery has a potential effect of preventing adjacent segmental degeneration.