腰椎斜外侧椎间融合术中终板损伤的原因分析

Analysis the causes of endplate injury in oblique lateral interbody fusion

目的探讨斜外侧椎间融合术(oblique lateral interbody fusion,OLIF)治疗腰椎病变术中终板损伤的特点,分析其原因,并提出预防措施。方法回顾性分析五个医疗中心2014年10月至2017年12月采用Stand-alone OLIF或OLIF联合椎弓根螺钉固定治疗腰椎病变术中出现终板损伤的35例患者临床资料。男7例,女28例;年龄(62.8±8.13)岁(范围:51~78岁)。腰椎间盘退行性病变2例、腰椎管狭窄症10例、腰椎退行性滑脱症17例、腰椎峡部裂伴或不伴椎体滑脱症2例、腰椎退行性侧凸4例。L3,42例、L4,521例、L2~43例、L3~54例、L2~53例、L1~52例。术前骨密度:T值>-1 SD 7例、T值-1^-2.5 SD 24例、T值<-2.5 SD 4例。其中高髂嵴5例。融合节段:单节段25例、双节段5例、三节段3例、四节段2例。术中均发生终板损伤,共发生于39个椎间隙40个终板,1个椎间隙上、下终板均有损伤,余为单终板损伤;上终板损伤35个、下终板损伤5个;合并椎体骨折3例。发生终板损伤节段融合器位于Ⅰ~Ⅱ区3枚、Ⅱ~Ⅲ区31枚、Ⅲ~Ⅳ区5枚。主要观察指标为腰痛视觉模拟评分(visual analog scale,VAS)、Oswestry功能障碍指数(Oswestry disability index,ODI)、椎间隙高度及融合器位置等。结果术中损伤终板的原因包括患者合并骨量减少或骨质疏松28例、术者操作不当9例、髂嵴过高5例、终板解剖形态变异5例、椎间隙明显狭窄4例、使用的融合器偏大3例及混合因素12例。所有患者获得(18.5±8.1)个月的随访。随访期间发生融合器横向移位3例,Stand-alone OLIF 1例、OLIF联合椎弓根螺钉固定2例。35例均出现融合器不同程度的沉降,其中7例行Stand-alone OLIF者二期附加后路椎弓根螺钉固定。椎间隙高度术后均获得良好地恢复,与术前的差异有统计学意义;但末次随访时出现较大的丢失,与术后比较差异有统计学意义。腰痛VAS评分由术前(6.6±2.2)分改善至末次随访时(1.3±0.74)分,ODI由术前36.3%±7.4%恢复至末次随访时9.6%±3.5%。末次随访时除3例不能明确外,余获得椎间融合,融合率为91.4%。结论OLIF术中终板损伤的发生率较高,终板损伤既有患者自身的因素,也有手术操作的原因。终板损伤与随访期间椎间隙高度下降、融合器沉降或移位密切相关,部分病例可能需要再次手术,故需加强终板损伤的预防,一旦出现应采取及时、有效的处理,并严密随访。

Objective To investigate the characteristics and causes of endplate injury in the oblique lateral interbody fusion for the treatment of lumbar diseases,and summarize the precaution of endplate injury.Methods Thirty-five cases of endplate injury were observed,which were originally treated with oblique lateral interbody fusion with or without pedicle screw fixation from October 2014 to December 2017.There were 7 males and 28 females,and the age ranged from 51 to 78 years old(averagely 62.8±8.13 years).There were 2 cases of lumbar disc degeneration,10 cases of lumbar canal stenosis,17 cases of lumbar degenerative spondylolisthesis,2 cases of lumbar spondylolysis with or without spondylolisthesis,and 4 cases of lumbar degenerative scoliosis.Lesion sites contained L3,4 in 2 cases,L4,5 in 21 cases,L2-4 in 3 cases,L3-5 in 4 cases,L2-5 in 3 cases and L1-5 in 2 cases.Preoperative bone mineral density examination revealed there were 7 cases of T>-1 SD,24 cases of-2.5 SD<T<-1 SD and 4 cases of T<-2.5 SD.There were 5 cases of high iliac crest.There were 25 cases of single segment,5 cases of double segment,3 cases of three segments,and 2 cases of four segments.Endplate injury occurred in all cases,and a total of 40 endplates occurred in 39 intervertebral spaces,of which the upper and lower endplates of 1 intervertebral space were injured,and the rest were single endplate injuries.There were 35 cases of upper endplate injury,5 cases of lower endplate injury and 3 cases combined with vertebral fracture.The cage location where the endplate injury occurred:3 cases in zoneⅠ-Ⅱ,31 cases in zoneⅡ-Ⅲand 5 cases in zoneⅢ-Ⅳ.The main observation indicators were Visual Analog Scale(VAS)for low back pain,Oswestry disability index(ODI),intervertebral space height,and position of cage.Results The reasons for endplate injury were:osteopenia or osteoporosis 28 cases,improper surgical steps 9 cases,high iliac crest 5 cases,endplate anatomical morphology variation 5 cases,obvious stenosis of the intervertebral space 4 cases,large cage 3 cases and mixed factors 12 cases.The follow-up time was 18.5±8.1 months.There was no pedicle screw loosen during the follow-up.There were 3 cases of lateral displacement of cage,including 1 case of Stand-alone OLIF,2 cases of OLIF combined with pedicle screw fixation.In all cases,different degrees of cage subsidence occurred.Among them,7 cases of Stand-alone OLIF were supplemented with posterior pedicle screw fixation.The intervertebral height of diseased segment was well restored postoperatively,which was statistically significant compared with preoperative.But there was significant loss during the follow-up,and the difference was statistically significant at the last follow-up.The low back pain VAS score was from 6.6±2.2 preoperative to 1.3±0.74 at the last follow-up,which was statistically different.The ODI was from 36.3%±7.4%preoperative to 9.6%±3.5%at the last follow-up,which was statistically different.Except 3 cases,the remaining had well interbody fusion,with the fusion rate of 91.4%.Conclusion The incidence of endplate injury during oblique lateral interbody fusion is high.The reasons of endplate injury include both the patient's factors and the surgical factors.Endplate injury is closely related to the decreased intervertebral space height during the follow-up period,as well as the settlement or displacement of cage.Some cases may require reoperation.The prevention of endplate injury should be strengthened.Once it occurs,timely and effective treatment should be taken,and follow-up should be done closely.