Analysis Of The Effect Of Short Segment Decompression And Fusion In Degenerative Scoliosis And Related Factors Of Adjacent Segment Disease

Objective: The purpose of this study was to analyse the clinical efficacy and the possible related factors of adjacent segment disease(ASD)in degenerative scoliosis(DS)patients after decompression and fusion,in order to provide reference for further optimization of clinical treatment plan and improve the treatment effect.Methods: Retrospective analysis was conducted on 37 cases of adult patients with degenerative scoliosis and undergoing short segment decompression and fusion admitted to our spinal department from January2016 to December 2019.Preoperative and postoperative oswestry disability index(ODI)and visual analogue scale(VAS)were compared to evaluate the postoperative clinical efficacy.According to the occurrence of symptomatic adjacent segment disease(ASD)at the last follow-up,the patients were divided into ASD Group and N-ASD Group.Three possible influence factors were included in this study: 1.Patient characteristics: gender,age,smoking,body mass index(BMI),preoperative back and leg VAS and ODI score;2.Surgical variables: number of fusion segment,surgical segment,operative time,amount of blood loss,and whether superior facet joint violation during surgery;3.Radiographic parameters: lumbar lordosis(LL),sacral slope(SS),pelvic tilt(PT),pelvic incidence(PI),the mismatch between pelvic incidence and lumbar lordosis(PI-LL),the L1 axis and S1 distance(LASD),coronal Cobb angle,preoperative intervertebral disc degeneration at adjacent segment.The t-test and chi-square test were used to compare the differences between the two groups.Results: The 37 patients were followed up for a mean of 27.5 months(12-58 months).Low back and leg VAS score and ODI score were reduced at3 months after surgery and at the last follow-up,with statistically significant differences(P<0.001).The mean improvement rates of 3 months postoperative and the last follow-up ODI scores were 40.3% and 48.6% respectively.In all37 patients,6 patients developed postoperative ASD,with an incidence of16.2%.Comparison of mean follow-up time,age,gender,smoking or not,BMI,preoperative low back and leg VAS and ODI score,number of fusion segments,surgical segments,operative time,blood loss,preoperative LL,SS,LASD,preoperative intervertebral disc degeneration in adjacent segments between the two groups showed no statistically significant differences(P>0.05).Compared with non-ASD group,preoperative PT(33.3±9.9 vs 21.0±8.7,P=0.004),preoperative PI(55.1±8.3 vs 45.9±7.0,P=0.007),preoperative PI-LL(32.3±15.7 vs 18.1±12.4,P=0.020),preoperative coronal Cobb angle(28.5± 4.3 vs 20.0 ± 7.2,P=0.010)were significantly higher in ASD group,with statistically significant differences.Conclusion: This study concluded that patients with degenerative scoliosis were often complicated with lumbar spinal stenosis,postoperative leg and low back pain and spinal function recovery were improved to varying degrees after short segment decompression and fusion.However,patients were generally elderly,and there was a risk of residual low back pain and accelerated degeneration of adjacent segment.At a mean follow-up of 27.5months,the incidence of ASD was 16.2%,and the occurrence of ASD may be related to the high values of preoperative PI,PT,PI-LL and coronal Cobb angle.This is helpful to assess the risk of ASD and optimize the clinical treatment plan,so as to reduce the incidence of ASD and improve the treatment effect.