Comparison Of Clinical And Imaging Featrues Between Isthmus Spondylolisthesis At L4 And L5

Objectives1.To compare the difference of imaging and clinical features between patients with isthmic spondylolisthesis(IS)at L4 and at L5.2.To explore the correlations among imaging parameters and the degree of spondylolisthesis,and the severity of clinical symptoms in patients with IS at L4 and at L5MethodsPatients hospitalized in our hospital from January 2011 to November 2018 due to L4 IS or L,IS were analyzed retrospectively.The general data to be collected included age,gender,height,weight and comorbidity.The parameters of lumbo-pelvic alignment were measured on standing lumbar lateral radiograph,including:pelvic incidence angle(PI),pelvic tilt angle(PT),sacral slope(SS),lumbar lordosis(LL),lower lumbar lordosis(LLL),lumbar 5 incidence(151),Lumbosacral angle(LSA).The degree of lumbar spondylolisthesis and the degree of disc degeneration were evaluated by slippage rate(SR)and modified Pfirrmann disc degeneration grade.Roussouly type of all patients was determined according to the shape of sagittal lumbar pelvis.The severity of clinical symptoms was assessed and ODI.The differences between the two groups were analyzed.The relationships among the parameters in L4 IS and L5 IS groups were studied.ResultsA total of 139 patients were included in this study,including 44 with L4 IS,95 with L5 IS.There were 44 men and 95 women.The average age of L4 IS group was significantly older than L,IS group(58.5±8.7 vs 52.8±10.1,p<0.01).LLL in L4 IS group was significantly smaller than that in L5 IS group(27.1±8.2 vs 30.9±9.3,p=0.021).There was no difference between two groups in other parameters.An agematched analysis was further performed and the results were similar.Among patients in L4 IS group,the most common type was type 2(43.2%).However,in L5 IS group,patients were concentrated in type 3(44.2%).In L5 IS group,PI,PT,LL,SS and L5I were positively correlated with SR(P<0.01),while LSK was negatively correlated with SR(P<0.01);in L4 IS group,only L5I was positively correlated with SR(P<0.01).In L5 IS group,SS was negatively correlated with ODI(P<0.05);in L4 IS group,there was no sagittal lumbar pelvic parameter significantly correlated with ODI.There was a negative correlation between DG and ODI in L5 IS group(P<0.05),but no significant correlation between DG and ODI in L4 IS group.There was a significant correlation between DG and SR in both groups(P<0.01),but no significant correlation between SR and ODI.Conclusions1.When compared with patients with L5 IS,patients with L4 IS were of older age and had straighter low lumbar curvature when they were obviously symptomatic.2.The sagittal lumbo-pelvic parameters have more complicated correlations with imaging grading and degree of clinical symptoms in patients with IS at L5.3.For patients with high PI and IS at L5,close follow-up and active treatment should be taken into consideration.For patient with IS at L4,LSI can be considered as an important predictor of slip progression.