Discectomy Combined With Annulus Fibrosus Repair For The Treatment Of Lumbar Disc Herniation: A Meta-analysis

Background: Lumbar disc herniation(LDH)refers to a series of clinical symptoms,such as lumbar back pain,numbness,pain and weakness of one or both lower extremities,caused by the breakthrough of annulus fibrosus(AF)in the nucleus pulposus of the intervertebral disc and the stimulation or compression of adjacent spinal nerve roots.Currently,for LDH patients with mild symptoms,conservative treatment such as medicine,bed rest and physiotherapy is often used,but some patients can not tolerate pain in the process of conservative treatment or for patients who have failed to undergo regular conservative treatment,surgery is often needed.Surgical interventions included discectomy,lumbar fusion and internal disc replacement.Discectomy considered as a classic procedure for the treatment of LDH.During the operation,some patients can feel the obvious relief of symptoms at the moment of being relieved of nerve compression.However,the amount of nucleus pulposus removal has been a controversial issue for clinicians.Some studies have suggested that excessive removal of nucleus pulposus tissue to reduce the rate of recurrence lumbar disc herniation.However,studies have shown that excessive removal of nucleus pulposus tissue could accelerate normal disc degeneration,reduce the height of the intervertebral disc after surgery,change the overall structure and biomechanics of the lumbar spine,and even lead to the risk of lumbar instability.Afterwards,some scholars supported limited removal of nucleus pulposus tissue and a small amount of nucleus pulposus removal,which could reduce the operation time and speed up the prognosis of patients,but the operation method has significantly increased the recurrence rate after surgery.In traditional surgery,there is no treatment for the ruptured AF after the removal of the nucleus pulposus tissue.Due to the poor nutritional supply in the intervertebral disc AF,the healing is slow and the early anti-stress strength is low,thus,there is a high risk of re-protrusion of nucleus pulposus at the original rupture site.In recent years,AF repair technology has been gradually applied to repair ruptured AF after nucleus pulposus removal,and the therapeutic effect of AF repair has been evaluated and analyzed in relevant literatures.However,due to the small sample size and inconsistent conclusions of a single literature,it is not enough to provide a basis for clinical treatment.Therefore,we performed current meta-analysis to investigate clinical effects of two methods for the treatment of LDH and look forward to providing evidence-based basis for the treatment of clinicians.Methods: We searched PubMed,Embase,Web of science,WanFang data and CNKI,until February,2019 for studies evaluating the treatment effect of lumbar disc herniation by two surgical methods.Two reviewers independently selected studies,assessed quality and extracted data based on the inclusion criteria of current study.The primary outcomes of this meta-analysis were recurrence rate,reoperation rate,postoperative reduction of VAS and ODI,postoperative complications.Secondary outcomes were operative time(mins),intraoperative blood loss(ml)and length of surgical incision(cm).This meta-analysis was conducted strictly in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)statement.The protocol for the meta-analysis was registered in the International Prospective Register of Systematic Reviews(ID = CRD42018110414).We used RevMan 5.3 for data statistics and analysis in our study.Results: Seven randomized controlled trials(RCTs)were included in the meta-analysis,including 1714 patients,911 in the repair group and 803 in the non-repaired group.The pooled results suggested that the recurrence rate and reoperation rate in the non-repair group were 2.16 and 1.74 times higher than those in the repair group [RR= 2.16,95% CI(1.50,3.10),P<0.01],[RR=1.74,95% CI(1.22,2.49),P<0.01].The rate of VAS relief in the repair group was significantly better than in non-repair group [WMD=0.22,95% CI(0.06,0.37),P <0.01],and did not increase the incidence of postoperative complications.There were no significant differences between the two surgical procedures in the ODI reduction [WMD=0.36,95% CI(-0.79,1.50),P=0.54],intraoperative blood loss(ml)[WMD =-1.23,95% CI(-4.46,2.00),P = 0.45] and the length of the surgical incision(cm)[WMD = 0.08,95% CI(-0.01,0.18),P=0.10].However,the operation time of the repair group was slightly longer than non-repair group [WMD =6.73,95% CI(2.80,10.66),P<0.01].Conclusions: Discectomy combined with annular repair is superior to discectomy regarding postoperative recurrence rate,reoperation rate and postoperative pain relief,but the operation time is slightly longer than the latter.There is no significant difference in intraoperative blood loss,length of surgical incision,postoperative complication rate and reduction in ODI between the two surgical procedures.However,due to the small number of studies and the small sample size,we expect a multi-center,large sample,high quality,double-blind RCT study to further update our conclusions.