Percutaneous Transforaminal Endoscopic Discectomy Versus Open Microdiscectomy for Lumbar Disc Herniation

A Systematic Review and Meta-Analysis

Pravesh S. Gadjradj, MD; Biswadjiet S. Harhangi, MD, PhD; Jantijn Amelink, BSc; Job van Susante, MD, PhD; Steven Kamper, PhD; Maurits van Tulder, PhD; Wilco C. Peul, MD, PhD; Carmen Vleggeert-Lankamp, MD, PhD; Sidney M. Rubinstein, PhD


Spine. 2021;46(8):538-549. 

In This Article

Abstract and Introduction


Study Design: Systematic review and meta-analysis.

Objective: To give a systematic overview of effectiveness of percutaneous transforaminal endoscopic discectomy (PTED) compared with open microdiscectomy (OM) in the treatment of lumbar disk herniation (LDH).

Summary of Background Data: The current standard procedure for the treatment of sciatica caused by LDH, is OM. PTED is an alternative surgical technique which is thought to be less invasive. It is unclear if PTED has comparable outcomes compared with OM.

Methods: Multiple online databases were systematically searched up to April 2020 for randomized controlled trials and prospective studies comparing PTED with OM for LDH. Primary outcomes were leg pain and functional status. Pooled effect estimates were calculated for the primary outcomes only and presented as standard mean differences (SMD) with their 95% confidence intervals (CI) at short (1-day postoperative), intermediate (3–6 months), and long-term (12 months).

Results: We identified 2276 citations, of which eventually 14 studies were included. There was substantial heterogeneity in effects on leg pain at short term. There is moderate quality evidence suggesting no difference in leg pain at intermediate (SMD 0.05, 95% CI –0.10–0.21) and long-term follow-up (SMD 0.11, 95% CI –0.30–0.53). Only one study measured functional status at short-term and reported no differences. There is moderate quality evidence suggesting no difference in functional status at intermediate (SMD –0.09, 95% CI –0.24–0.07) and long-term (SMD –0.11, 95% CI –0.45–0.24).

Conclusion: There is moderate quality evidence suggesting no difference in leg pain or functional status at intermediate and long-term follow-up between PTED and OM in the treatment of LDH. High quality, robust studies reporting on clinical outcomes and cost-effectiveness on the long term are lacking.

Level of Evidence: 2


Sciatica is a frequently used term to describe radiating leg pain. It is mostly caused by lumbar disc herniation (LDH).[1,2] Even though the natural course of sciatica is favorable and most cases respond to conservative treatment, surgery is deemed necessary in some cases.[3] The current standard procedure to decompress the nerve root by removing disc fragments, is open microdiscectomy (OM).[4]

In attempts to reduce the surgical invasiveness, techniques which use endoscopes to remove disc fragments were developed. The expectation was that by causing less tissue damage during surgery, patients would have less postoperative back pain, recover sooner from surgery, and have shorter duration of hospitalization.[5] Development of methods facilitating insertion of surgical endoscopes into the safe entry zone in the neuroforamen formed (also known as Kambin triangle), enabled the development of percutaneous transforaminal endoscopic discectomy (PTED).[6,7] During PTED no paraspinal muscles are deattached from their origin and bony anatomy is affected limited. Previous studies which have examined PTED demonstrated favorable clinical outcomes, with the result that percutaneous full-endoscopic discectomy has made its way into small scale clinical practice.[4,8,9]

A previous review published in 2009 which compared the effects of PTED with OM concluded that the quality of the evidence regarding effectiveness of PTED is low[10] and PTED could not be recommended for the treatment of LDH. Since then large observational studies as well as randomized controlled trials (RCTs) have examined the effects of endoscopic discectomy techniques versus OM, which have been summarized in recent reviews, including meta-analyses.[11–16] Despite similar aims, these meta-analyses differ in methodology. As a result, the uncertainty regarding the effectiveness of PTED compared with OM remains.

In 2014, a systematic review was published by our research group, comparing minimally invasive surgery with OM.[17] Due to the low number and high risk of bias of the included studies as well as small sample sizes, no pooled effect estimates were calculated for the effects of PTED versus OM.[18] Preliminary analysis of studies published since then, suggested that there were sufficient studies to warrant an update of our previous review, focusing on the effects of PTED versus OM in the treatment of LDH.