The efficacy and safety of microendoscopic discectomy compared with conventional microsurgical discectomy: a meta-analysis of randomised controlled trials

Purpose: The objective of this study was to compare the efficacy and safety of microendoscopicdiscectomy (MED) with conventional microsurgical discectomy (CMSD) for treatment of lumbar disc herniation (LDH). Methods: A comprehensive literature search was performed in PubMed, MEDLINE, EMBASE, Web of Science, Cochrane Library, ClinicalTrials.gov, SinoMed, and CNKI. Randomised controlled trials (RCTs) that compared MED with CMSD for the surgical management of LDH were included. These trials were carefully picked out following the inclusion and exclusion criteria. Two authors independently extracted data and assessed these trials’ quality according to the Cochrane Collaboration guidelines. Results: Ten randomized controlled trials (RCTs) with a total of 1953 patients met the inclusion criteria and were included in this meta-analysis. All patients underwent MED or CMSD. Pooled estimates showed that patients treated with microendoscopic discectomy had comparable effects in blood loss (WMD=9.50, 95% CI -5.06 to 24.07, P=0.20), serum levels of CPK (WMD=35.05, 95% CI -214.08 to 284.19, P=0.78), VAS of leg pain (WMD=0.05, 95% CI -0.46 to 0.56, P=0.85), VAS of back pain (WMD=0.27, 95% CI -0.08 to 0.63, P=0.14), ODI (WMD=1.22, 95% CI -0.13 to 2.56, P=0.08), hospital stay (WMD=0.14, 95% CI -0.07 to 0.34, P=0.19) and root injury (RD=0.01, 95% CI -0.00 to 0.02, P=0.23), but had shorter size of incision (WMD=-1.32, 95% CI -1.86 to -0.78, P<0.00001), longer surgical time (WMD=8.77, 95% CI 5.25 to 12.29, P<0.00001), higher risk of total complications (RD=0.06, 95% CI 0.02 to 0.10, P=0.002), higher risk of disc herniation recurrence (RR=1.84, 95% CI 1.05 to 3.23, P=0.03), higher risk of dural tear (RD=0.02, 95% CI 0.01 to 0.04, P=0.001), and more hospital costs (SMD=1.84, 95% CI 0.12 to 3.56, P=0.04), when compared with those treated with conventional microsurgical discectomy. Conclusions: Based on current evidence, microendoscopic discectomy with a small incision significantly increased the surgical time, total complications, disc herniation recurrence, dural tear and hospital costs, but had similar effects on blood loss, serum levels of CPK, clinical effect, root injury and hospital stay, when compared with conventional microsurgical discectomy.