Clinical Efficacy Of Oblique Lumbar Interbody Fusion In The Treatment Of Degenerative Lumbar Spondylolisthesis And Its Feasibility Research At The L5-S1 Level

PART ONE COMPARISON BETWEEN OBLIQUE LUMBAR INTERBODY FUSION AND MINIMALLY INVASIVE TRANSFORAMINAL LUMBAR INTERBODY FUSION FOR THE TREATMENT OF SINGLE-LEVEL DEGENERATIVE SPONDYLOLISTHESISBackground and Purpose Degenerative lumbar spondylolisthesis(DLS)is a common cause of severe low back pain,which seriously influences the patients’ life quality and working capacity.At present,oblique lumbar interbody fusion(OLIF)and minimally invasive transforaminal lumbar interbody fusion(MIS-TLIF)are widely used in the treatment of degenerative lumbar spondylolisthesis and other degenerative lumbar diseases.However,there are few studies comparing their features of minimal-invasive and clinical effects.In this study,a single center retrospective study was conducted to compare the clinical efficacy of OLIF and TLIF in single-level DLS,providing evidence for clinical treatment.Materials and Methods We retrospectively analyzed patients underwent single-level DLS surgery in our department from 2017 to 2019.The enrolled patients were divided into the OLIF group and the TLIF group according to the surgical method.Clinical outcomes included operation time,operation blood loss,postoperative drainage,hospital stay,hidden hemorrhage volume,albumin loss,the CRP and ESR on the first day after operation,visual analog scale(VAS)score,Oswestry disability index(ODI),and imaging outcomes included disc height(DH),lumbar lordosis(LL),fused segmental lordosis(FSL),slip percentage(SP %),bone fusion rate and complications were recorded and analyzed.Results A total of 57 patients were finally included,and there were 21 patients and 36 patients in the OLIF group and the MIS-TLIF group,respectively.The OLIF group had shorter operation time(P < 0.001),less intraoperative blood loss(P = 0.008),less postoperative drainage(P = 0.004),less PCIA usage(P = 0.011)and less hidden hemorrhage volume(P = 0.033).There was no significant difference in VAS score and ODI index between the two groups before operation,3 months postoperative,6 months postoperative and at the last follow-up.Compared with the MIS-TLIF group,the VAS score and ODI index of the OLIF group were significantly improved at 1 week postoperative(VAS score: P < 0.001;ODI index: P < 0.001).There was no significant difference in disc height,fused segmental lordosis and slip percentage between the two groups.The bone fusion rate of the OLIF group and the MIS-TLIF group were 76.19%,90.48%,100% and 72.22%,83.33%,97.22% at 3 months postoperative,6 months postoperative and at the last follow-up,respectively,with no significant difference(P = 0.743,0.724 and 0.594).There were 4 complications in the OLIF group and 5 in the MIS-TLIF group.There was no significant difference in the incidence of complications between the two groups.Conclusions Both OLIF and MIS-TLIF are ideal surgical methods for the treatment of degenerative lumbar spondylolisthesis.The clinical efficacy of the two surgical methods is similar,but OLIF is more minimally invasive and has obvious advantages at the early stage after operation.During the procedure of MIS-TLIF,attention should be paid to protect the nerve structure and avoid nerve root injury.PART TWO FEASIBILITY RESEARCH OF OLIF IN L5-S1 SEGMENT AND INTRODUCING V-LINE TO CHOOSE SURGICAL CORRIDOR BASED ON CT IMAGESBackground OLIF51 could be described as laterally-positioned ALIF,but it was superior to ALIF in many aspects.Damage to LCIV is the most threatening complication associated with OLIF51,which impeding the wide application of this technology.For OLIF51,we could choose the medial approach or the lateral approach.However,which approach might reduce the risk of vascular injury has not been comprehensively studied.Purpose A retrospective imaging study assessing the availability of oblique lumbar interbody fusion at the level of L5-S1(OLIF51)and to choose ideal surgical corridor in OLIF51 by introducing V-line.Methods The axial views through the center of L5-S1 disc were reviewed.We adopt 18 mm as the width of the simulated surgical corridor.The midline of the surgical corridor is at the center of L5-S1 disc.According to the traction distance of the left iliac vein(LCIV)and psoas major(PM),we defined all the subjects as V(+)(traction-difficultly LCIV),V(-)(traction-friendly LCIV),P(+)(traction-difficultly PM)and P(-)(traction-friendly PM). V-line was defined as a straight line dividing equally the simulated surgical corridor.All cases were divided into 2 groups: The V-line(+)group,more than half of the LCIV region is located in ventral part of V-line;the V-line(-)group,more than half of the LCIV region is located in dorsal part of V-line.Multiple variables regressive analysis was conducted to analyze the independent risk factors of V-line(+).Results V-line(+)was found in 36(38.7%)patients and V-line(-)in 57(61.3%).Incidence of V(+)and P(+)were 35.4%(33/93)and 30.1%(28/93),respectively.16.1%(15/93)subjects processed V(+)and P(+)at the same time.The independent risk factor of V-line(+)were gender of male(P = 0.034,OR: 12.152)and medial position of LCIV(P < 0.001,OR: 265.085).High iliac crest was a significant independent protective factor(P = 0.001,OR: 0.750).Conclusions Most patients were suitable for OLIF51.V-line could assess the injury risk of LCIV.Patients who are V-line(+),mainly among males having the LCIV near the midline or the iliac crest relatively low,a surgical corridor external to the LCIV should be taken into consideration.