Lumbar disc herniation (LDH) is a common medical condition with a pathological process that leads to spinal surgery. The annulus fibrosus of an intervertebral disc fracture and allows the soft central portion, the nucleus pulposus, to protrude beyond the damaged annulus fibrosus [1] . Lumbar disc herniation is a major cause of low back pain and sciatica [2] . Advances in surgical techniques have provided minimally invasive approaches for its treatment, including percutaneous endoscopic discectomy (PELD) and microdiscectomy [3] . The most common complications within this procedure are dural tears, epidural hematoma, transient dysesthesia, and incomplete decompression [4] . This article aims to compare clinical outcomes, complications, and recovery between both techniques.

Embase databases until October 2024, using terms such as “percutaneous endoscopic lumbar discectomy”, “lumbar microdiscectomy”, “lumbar disc herniation”, and “minimally invasive spine surgery”. Studies were included that compared both techniques in terms of efficacy, recovery times, complications and hernia recurrence, where discectomy and microdiscectomy were used. A revision of articles published between 2019 and October 2024 was considered. Complete studies accessible in full text were included. Inclusion criteria were patients with symptoms of lumbar radiculopathy or disabling low back pain, patients who underwent percutaneous endoscopic discectomy (PELD) or open microdiscectomy (OLMD), patients with Modic changes 1 - 3 and studies with a minimum follow-up of 6 months. Exclusion criteria were those who received other types of spinal surgeries not related to discectomy or microdiscectomy, as well as those including patients with spinal tumor surgeries, spinal fusion, or severe scoliosis. ( Figure 1 )

The systematic review included six studies that compared the postoperative outcomes of lumbar disc herniation resection using percutaneous endoscopic discectomy (PELD) versus microdiscectomy (OLMD) or micro endoscopic tubular resection (TMD). The studies presented outcomes in terms of Visual Analogue Pain Scale (VAS), hospital stay, time to return to work, and postoperative complications.

Both techniques are safe and effective for the treatment of lumbar disc herniation, offering pain relief and improved function. PELD has the advantage of being a minimally invasive technique that allows for faster recovery and lower initial complication rates, but requires a steeper learning curve. On the other hand, microdiscectomy remains the gold standard in terms of complete herniation resolution and a slightly lower reoperation rate. The results of this systematic review suggest that percutaneous endoscopic discectomy (PELD) offers several advantages over open microdiscectomy (OLMD) and microendoscopic tubular discectomy (TMD), particularly in terms of hospitalization time, return to work, and complication rate. Although the reviewed studies did not always present specific data on preoperative and postoperative VAS values, most agree that PELD tends to be more effective in reducing pain, with faster postoperative recovery. Furthermore, the lower incidence of complications in PELD, as observed in several studies, supports the use of this minimally invasive technique as an effective alternative to OLMD, especially in patients seeking faster recovery and fewer complications. However, studies such as those by Jung et al. [8] and Lee & Ahn [9] pointed out the need to consider the learning curve of PELD, which may affect outcomes in less experienced centers. The reviewed studies indicated that while both techniques are effective in reducing pain and improving function, PELD appears to be superior in terms of shorter hospital stay, shorter recovery time and fewer complications. However, further research is required to assess the long-term benefits and reduce variability between studies in terms of the accuracy of results. PELD represents a promising surgical option for patients with lumbar disc herniation, with significant pain reduction, shorter hospital stay and faster return to work compared to OLMD or TMD, and with a favorable complication profile. The results of this review support the use of percutaneous endoscopic discectomy (PELD) as an effective and safe technique for the resection of lumbar disc herniations, with several advantages over microdiscectomy (OLMD) and tubular discectomy (TMD). Reduced postoperative pain, shorter hospital stay, faster return to work, and lower incidence of complications make PELD a superior option for many patients. The PELD learning curve, mentioned by Lee & Ahn [9] , is an aspect to consider as it may influence the results, but the potential benefits of this minimally invasive technique are evident. Both techniques are effective, with PELD demonstrating significant clinical advantages in terms of postoperative recovery, suggesting that it could be the preferred option in many clinical settings, especially in centers with experience in endoscopic procedures.

Discectomy (PELD) has been shown to be significantly effective in reducing postoperative pain compared to microdiscectomy (OLMD/TMD). In studies such as that of Priola et al. [5] , a remarkable decrease in long-term pain was observed, confirming its effectiveness in the management of low back pain resulting from disc herniation. These results underline the ability of PELD to provide sustained relief in patients. Regarding hospitalization time, PELD consistently showed a reduction in hospital stay days compared to OLMD and TMD. All the reviewed studies agreed that PELD offers a faster recovery, positively impacting the efficiency of the health system by requiring fewer hospital resources. In addition, patients undergoing PELD also showed a faster return to work, as pointed out by studies such as those by Wei et al. [6] and Bombieri et al. [7] , which reinforces the idea that this technique accelerates the functional recovery of patients. Additionally, PELD was associated with a lower complication rate compared to OLMD/TMD. This includes fewer reoperations and fewer intraoperative complications, suggesting that PELD is a safer and less invasive option. However, PELD presents a considerable learning curve, implying that outcomes may vary depending on the surgical experience available and that specialized training is required to maximize the benefits of the technique. PELD offers multiple advantages over OLMD and TMD, mainly in terms of faster recovery, shorter hospital stay, and fewer complications [10] . However, its success is highly dependent on surgical experience [11] . Therefore, PELD should be considered a first-line option in lumbar disc herniation resection, especially in patients seeking a less invasive procedure with accelerated recovery [12] - [14] .

The authors are grateful to the participants and researchers of the primary studies identified for the present review.

LDH: Lumbar disk herniation; MD: Microdiscectomy; MI: Minimally invasive; PRISM: Preferred Reporting Items for Systematic Reviews.