A Comparison Study Of Unilateral Interlaminar Decompression Using MED And The Laminectomy Decompression Combined With Internal Fixation In Degenerative Lumbar Spinal Stenosis Treatment

BackgroundDegenerative Lumbar spinal stenosis(DLSS)is a common clinical disease,which is more common in middle-aged and elderly people.It is usually one of the important causes of waist and leg pain in middle-aged and elderly patients.According to reports,the incidence of adults is about 1.7%to 10%[1,2].When conservative treatment fails,surgery is the most effective way to relieve the patient’s pain[3].Spinal canal decompression surgery can effectively alleviate the symptoms of spinal canal stenosis.Because decompression may cause potential iatrogenic lumbar instability,simple decompression surgery is often not effective.Research shows that decompression combined with fusion or fusion surgery is an effective way to treat lumbar degenerative diseases[4].Traditional laminectomy decompression surgery is the "gold standard" for DLSS[5].However,although laminectomy can achieve sufficient decompression,the structure of the posterior column of the spine has been extensively removed,which can easily cause postoperative iatrogenic lumbar instability[6,7].In addition,it is easy to cause postoperative adhesion of muscle and dural scar,resulting in narrowing and pulling of the dura,which will cause iatrogenic spinal stenosis[8].In recent years,scholars have continuously tried a variety of minimally invasive treatments.The earliest channel surgery is MED,which has less bleeding,less trauma,and decompression effects comparable to traditional surgery.Since then,the minimally invasive channel technology has undergone X-tube technology[9],Quadrant expandable channel technology[10],METRx Ⅱ technology and Vista technology[11].The MED system used in this study is an improvement of the working channel of the movable cone MED system,which uses a double retractor to retract and expose the nerve[12].This can not only swing the working channel to achieve the purpose of"unilateral approach,bilateral decompression",but also complete the placement of the expansion cage under the channel.Since minimally invasive decompression is limited,some scholars worry that decompression is sufficient?What is the specific effect?What are the advantages over traditional methods of decompression?There is no clear conclusion whether MED decompression or laminectomy decompression combined with internal fixation can better treat degenerative lumbar spinal stenosis.This study aims to compare the advantages and disadvantages of the two surgical methods through a retrospective study of two groups cases.ObjectiveIn order to investigate the efficacy of unilateral interlaminar decompression using MED and laminectomy decompression combined with internal fixation in the treatment of degenerative lumbar spinal stenosis,and its characteristics were compared and analyzed to provide ideas and basis.MethodA retrospective analysis of 71 patients with degenerative lumbar spinal stenosis treated in the Department of Orthopaedics of the First Affiliated Hospital of Zhengzhou University from May 2015 to May 2017,37 males and 34 females.Among them,35 cases were treated with unilateral interlaminar decompression using MED(group A),20 males and 15 females;36 cases were treated with laminectomy decompression(group B),17 males and 19 females.The preoperative basic data,operation time,intraoperative blood loss and postoperative complications of the two groups of patients were compared and analyzed.The clinical efficacy grade was evaluated by Japanese Orthopaedic Association Scores(JOA).The improvement of waist and leg pain was evaluated by Visual Analogue Scale(VAS).The degree of postoperative daily life impact was evaluated by Oswestry Disability Index(ODI).ResultsAll the 71 patients underwent surgery successfully.All patients were followed up for an average of 14 months(12～16months).No screw fractures,deep and incision-related infections,and displacement of the fusion cage were found during postoperative follow-up.There were no significant differences in the basic data such as age,sex,disease duration,average hospitalization day between the two groups(P>0.05).Surgical condition:The blood loss and operation time in group A were less than those in group B,and the difference was statistically significant(P<0.05);Evaluation of postoperative efficacy:Group A was excellent in 25 cases(71.4%),good in 9 cases(25.7%),fair in 1 case(2.9%),poor in 0 cases(0.0%),and the excellent and good rate was 97.1%(34/35);Group B was excellent in 24 cases(66.7%),good in 11 cases(30.6%),fair in 1 case(2.8%),and poor in 0 cases(0.0%).The excellent and good rate was 97.2%(35/36);Statistical analysis showed no significant difference in postoperative clinical efficacy between the two groups(x2=0.206,P=0.902).The VAS score and ODI were significantly improved in the two groups(P<0.05)at 3,6,and 12 months after surgery,but there was no significant difference between the two groups(P>0.05).ConclusionsUnilateral interlaminar decompression using MED and laminectomy decompression combined with internal fixation all have good clinical effects as surgical methods for treating degenerative lumbar spinal stenosis.However,the former has the characteristics of short operation time and low intraoperative blood loss.It can not only meet the requirements of spinal canal decompression,but also less damage to the lumbar spine,and more effectively retain the lumbar spine structure and function.