There is an old Korean saying about medical promotion: “The best way of promotion comes from the patients who underwent this surgery, mouth to mouth in the nearby local area.” It means there is fact, result, confidence, and progress in detail, even with feelings and emotions during the period of treatment. Nowadays, in the era of wireless social media, “mouth to mouth” has become “mouths to mouths,” much faster and on a much wider national scale. This study reports well on this phenomenon; it must be one of the common ways of natural communication. The speed of the spread of this technique and patients’ needs through medical promotion has become much faster than with conventional open techniques. This has likely been helped by social media through recording and reviewing on a monitor.

The basal difference between the en bloc & two-wings and the piecemeal technique is that in the first two groups, flavectomy is attempted after completing upper and lower laminectomy, with careful dissection of the ligamentum flavum (LF) insertion point, securing enough space between the dura and LF, and creating a working space for gently inserting an instrument, especially on the contralateral side. Therefore, there is less risk of dural tear. In the last group, with the piecemeal resection technique, flavectomy may be performed simultaneously with laminectomy, area by area. This means that instrument handling and flavectomy must be performed in a still narrow working space. A Kerrison punch is attempted to be inserted into the narrow and jammed space between the laminar spur and LF. This report provides evidence of a safe workflow for decompression: laminectomy first, followed by flavectomy, to protect the dura and avoid unnecessary dural tears. One wing or two wings does not matter in terms of decompressing one side first and then the other side later.

Debridement and irrigation are the first strategy for infection. From this point of view, endoscopic surgery under continuous irrigation is one of the best options for infectious spondylitis. Furthermore, less soft tissue dissection using an endoscope must be less harmful to soft tissue healing, in contrast to wider dissection required to reach deeper pathology. It is good evidence of an effective approach for infectious spondylitis.

The larger the amount of bone graft, the better the guarantee for solid and early fusion. However, in continuous water flow, fine hydroxyapatite granules, small bone chips, and even mixed demineralized bone matrix could be easily washed out during the attempt at caging, because at that time we need to increase water input to see structural margins clearly and avoid dural or root injury. So, in terms of bone material grafting, the open technique is much superior to endoscopic caging. How can we overcome material gushing out during the stage of grafting and caging in endoscopic fusion?

Clinical severity and progression of degenerative spondylosis are not only defined by the percentage of ventral slip, but also by how much disc space has collapsed or whether there is an endplate stress fracture on magnetic resonance sagittal view. Most degenerative spondylosis in senile patients shows grade I, lower grade, or sometimes no or minimal change of ventral slip-on flexion and extension views. However, only decompression of lower-grade cases with endplate collapse or fracture shows continuous buttock and referred pain. In studying decompression-alone for degenerative spondylosis, disc collapsing condition and endplate status should be considered. Without that, most young surgeon recruits become confused and misunderstand the results of the study as a common one. In the early stage, with relatively good disc height and sound endplate in observational radiographic instability, no fusion is needed for the listhesis itself; decompression alone is enough for clinical satisfaction. In the late stage, with endplate fracture—meaning continuous clinical symptomatic instability—fusion is definitely needed to stop buttock pain coming from the fracture rather than from motion.

One of the main purposes of endoscopic spine surgery is preserving normal structures as much as possible, including the facet joint. To do that in the transforaminal approach, the access point should start far laterally to reach the ventral surface of the foramen directly, without burring off the isthmus, lateral side of the lamina, or even the superior articular process. This study clearly reveals why we should move the portal position far laterally. Good results came from the change to a far-lateral portal position, which is different from conventional tubular surgery or classic unilateral biportal endoscopy (UBE) with portals placed directly above the lateral margin of the isthmus.

The main technical benefit of uniportal or biportal endoscopy-assisted lumbar fusion might be unilateral laminotomy for bilateral decompression, laminectomy on one side while preserving the other facet, and indirect foraminal decompression using disc height restoration by caging. This point could be a main weak point and one of the reasons for clinical dissatisfaction. If there is endplate subsidence due to caging—which is a common occurrence because most patients in need of fusion surgery have osteopenia or osteoporosis—there may be persistent chronic back and buttock pain after endoscopic fusion. Cage subsidence tends to occur relatively early, resulting in screw loosening, foraminal recollapse, and delayed union, with chronic and moderate back and buttock pain caused by microfracture of the endplate and irritation of the sinovertebral nerve endings in the vertebral body. A systematic review should focus on why there is a higher rate of cage subsidence in endoscopic lumbar fusion.

This is a well-defined concept of learning curve of new spinal techniques. It is not only for learners but also mentors on learning and teaching something from or to someone. And also well documented are educational tools nowadays. If UBE are willing to be a standard technique generally for degenerative spinal diseases, standard decompression technique should be well organized, not by dependent on personal eccentric experience but by common shared skills. However, all techniques came from cumulative experiences of very personal, specific, special conditions of patient’s symptoms, medical conditions and needs on surgical interventions. So, we cannot insist on only one correct technical approach on UBE. Such diversity and imperfection on learning and teaching, however, can be a dynamic motive to develop UBE from the better to the best.