Background/Aims: Activation of the cold receptor, transient receptor potential melastatin 8 (TRPM8) by menthol inhibits esophageal secondary peristalsis in healthy adults. Ineffective esophageal motility (IEM) is common. This study is to evaluate the effects of acute infusion of menthol on esophageal peristalsis in patients with IEM. Methods: Twenty patients with IEM (males 11, mean age 36) were studied for esophageal peristalsis using high-resolution manometry. All participant had primary peristalsis performed with 10 water swallows and secondary peristalsis generated with 10 rapid air injections of 20 mL via mid-esophageal infusion port. Two different sessions by randomly performing acute administration of placebo or menthol (3 mM) were used for testing their effects on esophageal peristalsis. Results: Menthol infusion had no effects on distal contractile integral (P = 0.471), distal latency (P = 0.58), or complete peristalsis (P = 0.251). Menthol infusion did not change basal lower esophageal sphincter pressure (P = 0.321), esophagogastric junction contractile integral (P = 0.758), or integrated relaxation pressure (P = 0.375) of primary peristalsis, but reduced upper esophageal sphincter pressure (P = 0.037). Infusion of menthol significantly reduced the frequency of secondary peristalsis for air injects of 20 mL (P = 0.002), but did not affect distal contractile integral of secondary peristalsis for air injections of 20 mL. Conclusion This work has suggested that activation of TRPM8 by menthol can attenuate mechanosensitivity of secondary peristalsis in response to rapid air distension regardless of the presence of IEM.

Background/Aims: Activation of the cold receptor, transient receptor potential melastatin 8 (TRPM8) by menthol inhibits esophageal secondary peristalsis in healthy adults. Ineffective esophageal motility (IEM) is common. This study is to evaluate the effects of acute infusion of menthol on esophageal peristalsis in patients with IEM. Methods: Twenty patients with IEM (males 11, mean age 36) were studied for esophageal peristalsis using high-resolution manometry. All participant had primary peristalsis performed with 10 water swallows and secondary peristalsis generated with 10 rapid air injections of 20 mL via mid-esophageal infusion port. Two different sessions by randomly performing acute administration of placebo or menthol (3 mM) were used for testing their effects on esophageal peristalsis. Results: Menthol infusion had no effects on distal contractile integral (P = 0.471), distal latency (P = 0.58), or complete peristalsis (P = 0.251). Menthol infusion did not change basal lower esophageal sphincter pressure (P = 0.321), esophagogastric junction contractile integral (P = 0.758), or integrated relaxation pressure (P = 0.375) of primary peristalsis, but reduced upper esophageal sphincter pressure (P = 0.037). Infusion of menthol significantly reduced the frequency of secondary peristalsis for air injects of 20 mL (P = 0.002), but did not affect distal contractile integral of secondary peristalsis for air injections of 20 mL. Conclusion This work has suggested that activation of TRPM8 by menthol can attenuate mechanosensitivity of secondary peristalsis in response to rapid air distension regardless of the presence of IEM.

This video presents a case of L4–5 unstable spondylolisthesis treated with full-endoscopic transforaminal lumbar interbody fusion (Endo-TLIF), emphasizing the GUARD (Glider Used as a Rotary Device) technique for nerve root protection. This innovative approach involves controlled rotation of the cage glider before cage insertion to minimize the risk of nerve root injury, a significant complication in Endo-TLIF procedures. The GUARD technique, validated in previous cadaveric studies, provides enhanced safety during cage insertion by protecting the nerve root. A 48-year-old woman with a 3-year history of progressive low back pain and bilateral lower extremity radiculopathy (right-sided predominance) was diagnosed with L4–5 unstable spondylolisthesis and spinal stenosis. After failure of conservative management, she underwent uniportal full-endoscopic facet-resecting transforaminal lumbar interbody fusion using the GUARD technique. Postoperatively, the patient experienced significant symptomatic improvement and resolution of radiculopathy, without any intraoperative nerve root injury or postoperative neurological deficits. This case demonstrates the effectiveness of the GUARD technique in reducing neurological complications and improving patient outcomes.

Objective: Uniportal full-endoscopic transforaminal lumbar interbody fusion (FE-TLIF) carries a unique risk of nerve traction and abrasion injury during cage insertion. This study aims to evaluate the clinical efficacy of the GUARD technique and delayed ligamentum flavectomy in reducing postoperative radicular pain and neurapraxia in patients undergoing uniportal FE-TLIF. Methods: A retrospective analysis was conducted on 45 patients with an average age of 53.9±12.4 years who underwent either FE facet-sparing TLIF (FE fs-TLIF) or FE facet-resecting TLIF (FE fr-TLIF). Patients were divided into 2 groups: the sentinel group (21 patients) using traditional sentinel pin techniques, and the GUARD group (24 patients) using the GUARD technique with delayed ligamentum flavectomy. Patient-reported outcomes included the visual analogue scale (VAS) for leg and back pain, and Oswestry Disability Index. Complication rates, including incidental durotomy, postoperative neurapraxia, and hematoma, were also documented. Results: Postoperative radicular pain in the legs was significantly reduced at 6 weeks in the GUARD group compared to the sentinel group (VAS: 2.201 vs. 3.267, p=0.021). The incidence of postoperative neurapraxia was markedly lower in the GUARD group (0% vs. 19%, p=0.047). Both groups showed similar improvements in disc height, segmental lordosis, and lumbar lordosis at the 1-year follow-up, with no significant differences in endplate injury or fusion rates. Conclusion The GUARD technique and delayed ligamentum flavectomy significantly enhance patient safety by reducing postoperative radicular pain and neurapraxia without incurring additional costs. These techniques are easy to learn and integrate into existing surgical workflows, offering a valuable improvement for surgeons performing FE-TLIF procedures.

Background/Aims: Activation of the cold receptor, transient receptor potential melastatin 8 (TRPM8) by menthol inhibits esophageal secondary peristalsis in healthy adults. Ineffective esophageal motility (IEM) is common. This study is to evaluate the effects of acute infusion of menthol on esophageal peristalsis in patients with IEM. Methods: Twenty patients with IEM (males 11, mean age 36) were studied for esophageal peristalsis using high-resolution manometry. All participant had primary peristalsis performed with 10 water swallows and secondary peristalsis generated with 10 rapid air injections of 20 mL via mid-esophageal infusion port. Two different sessions by randomly performing acute administration of placebo or menthol (3 mM) were used for testing their effects on esophageal peristalsis. Results: Menthol infusion had no effects on distal contractile integral (P = 0.471), distal latency (P = 0.58), or complete peristalsis (P = 0.251). Menthol infusion did not change basal lower esophageal sphincter pressure (P = 0.321), esophagogastric junction contractile integral (P = 0.758), or integrated relaxation pressure (P = 0.375) of primary peristalsis, but reduced upper esophageal sphincter pressure (P = 0.037). Infusion of menthol significantly reduced the frequency of secondary peristalsis for air injects of 20 mL (P = 0.002), but did not affect distal contractile integral of secondary peristalsis for air injections of 20 mL. Conclusion This work has suggested that activation of TRPM8 by menthol can attenuate mechanosensitivity of secondary peristalsis in response to rapid air distension regardless of the presence of IEM.

This video presents a case of L4–5 unstable spondylolisthesis treated with full-endoscopic transforaminal lumbar interbody fusion (Endo-TLIF), emphasizing the GUARD (Glider Used as a Rotary Device) technique for nerve root protection. This innovative approach involves controlled rotation of the cage glider before cage insertion to minimize the risk of nerve root injury, a significant complication in Endo-TLIF procedures. The GUARD technique, validated in previous cadaveric studies, provides enhanced safety during cage insertion by protecting the nerve root. A 48-year-old woman with a 3-year history of progressive low back pain and bilateral lower extremity radiculopathy (right-sided predominance) was diagnosed with L4–5 unstable spondylolisthesis and spinal stenosis. After failure of conservative management, she underwent uniportal full-endoscopic facet-resecting transforaminal lumbar interbody fusion using the GUARD technique. Postoperatively, the patient experienced significant symptomatic improvement and resolution of radiculopathy, without any intraoperative nerve root injury or postoperative neurological deficits. This case demonstrates the effectiveness of the GUARD technique in reducing neurological complications and improving patient outcomes.

Objective: Uniportal full-endoscopic transforaminal lumbar interbody fusion (FE-TLIF) carries a unique risk of nerve traction and abrasion injury during cage insertion. This study aims to evaluate the clinical efficacy of the GUARD technique and delayed ligamentum flavectomy in reducing postoperative radicular pain and neurapraxia in patients undergoing uniportal FE-TLIF. Methods: A retrospective analysis was conducted on 45 patients with an average age of 53.9±12.4 years who underwent either FE facet-sparing TLIF (FE fs-TLIF) or FE facet-resecting TLIF (FE fr-TLIF). Patients were divided into 2 groups: the sentinel group (21 patients) using traditional sentinel pin techniques, and the GUARD group (24 patients) using the GUARD technique with delayed ligamentum flavectomy. Patient-reported outcomes included the visual analogue scale (VAS) for leg and back pain, and Oswestry Disability Index. Complication rates, including incidental durotomy, postoperative neurapraxia, and hematoma, were also documented. Results: Postoperative radicular pain in the legs was significantly reduced at 6 weeks in the GUARD group compared to the sentinel group (VAS: 2.201 vs. 3.267, p=0.021). The incidence of postoperative neurapraxia was markedly lower in the GUARD group (0% vs. 19%, p=0.047). Both groups showed similar improvements in disc height, segmental lordosis, and lumbar lordosis at the 1-year follow-up, with no significant differences in endplate injury or fusion rates. Conclusion The GUARD technique and delayed ligamentum flavectomy significantly enhance patient safety by reducing postoperative radicular pain and neurapraxia without incurring additional costs. These techniques are easy to learn and integrate into existing surgical workflows, offering a valuable improvement for surgeons performing FE-TLIF procedures.

This video presents a case of L4–5 unstable spondylolisthesis treated with full-endoscopic transforaminal lumbar interbody fusion (Endo-TLIF), emphasizing the GUARD (Glider Used as a Rotary Device) technique for nerve root protection. This innovative approach involves controlled rotation of the cage glider before cage insertion to minimize the risk of nerve root injury, a significant complication in Endo-TLIF procedures. The GUARD technique, validated in previous cadaveric studies, provides enhanced safety during cage insertion by protecting the nerve root. A 48-year-old woman with a 3-year history of progressive low back pain and bilateral lower extremity radiculopathy (right-sided predominance) was diagnosed with L4–5 unstable spondylolisthesis and spinal stenosis. After failure of conservative management, she underwent uniportal full-endoscopic facet-resecting transforaminal lumbar interbody fusion using the GUARD technique. Postoperatively, the patient experienced significant symptomatic improvement and resolution of radiculopathy, without any intraoperative nerve root injury or postoperative neurological deficits. This case demonstrates the effectiveness of the GUARD technique in reducing neurological complications and improving patient outcomes.

Objective: Uniportal full-endoscopic transforaminal lumbar interbody fusion (FE-TLIF) carries a unique risk of nerve traction and abrasion injury during cage insertion. This study aims to evaluate the clinical efficacy of the GUARD technique and delayed ligamentum flavectomy in reducing postoperative radicular pain and neurapraxia in patients undergoing uniportal FE-TLIF. Methods: A retrospective analysis was conducted on 45 patients with an average age of 53.9±12.4 years who underwent either FE facet-sparing TLIF (FE fs-TLIF) or FE facet-resecting TLIF (FE fr-TLIF). Patients were divided into 2 groups: the sentinel group (21 patients) using traditional sentinel pin techniques, and the GUARD group (24 patients) using the GUARD technique with delayed ligamentum flavectomy. Patient-reported outcomes included the visual analogue scale (VAS) for leg and back pain, and Oswestry Disability Index. Complication rates, including incidental durotomy, postoperative neurapraxia, and hematoma, were also documented. Results: Postoperative radicular pain in the legs was significantly reduced at 6 weeks in the GUARD group compared to the sentinel group (VAS: 2.201 vs. 3.267, p=0.021). The incidence of postoperative neurapraxia was markedly lower in the GUARD group (0% vs. 19%, p=0.047). Both groups showed similar improvements in disc height, segmental lordosis, and lumbar lordosis at the 1-year follow-up, with no significant differences in endplate injury or fusion rates. Conclusion The GUARD technique and delayed ligamentum flavectomy significantly enhance patient safety by reducing postoperative radicular pain and neurapraxia without incurring additional costs. These techniques are easy to learn and integrate into existing surgical workflows, offering a valuable improvement for surgeons performing FE-TLIF procedures.

This video presents a case of L4–5 unstable spondylolisthesis treated with full-endoscopic transforaminal lumbar interbody fusion (Endo-TLIF), emphasizing the GUARD (Glider Used as a Rotary Device) technique for nerve root protection. This innovative approach involves controlled rotation of the cage glider before cage insertion to minimize the risk of nerve root injury, a significant complication in Endo-TLIF procedures. The GUARD technique, validated in previous cadaveric studies, provides enhanced safety during cage insertion by protecting the nerve root. A 48-year-old woman with a 3-year history of progressive low back pain and bilateral lower extremity radiculopathy (right-sided predominance) was diagnosed with L4–5 unstable spondylolisthesis and spinal stenosis. After failure of conservative management, she underwent uniportal full-endoscopic facet-resecting transforaminal lumbar interbody fusion using the GUARD technique. Postoperatively, the patient experienced significant symptomatic improvement and resolution of radiculopathy, without any intraoperative nerve root injury or postoperative neurological deficits. This case demonstrates the effectiveness of the GUARD technique in reducing neurological complications and improving patient outcomes.