{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T03:10:40Z","timestamp":1792638640220,"version":"4.5.0"},"reference-count":35,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,9,3]],"date-time":"2021-09-03T00:00:00Z","timestamp":1630627200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Objective: There is limited literature comparing the uniportal full endoscopic posterolateral transforaminal lumbar interbody fusion outside-in approach (ETLIF (O)) with the inside-out approach (ETLIF (I)). Methods: Radiological evaluation was performed on disc height restoration and coronal wedging angle, and operation time (inferior articular process resection time\/total operation time) and clinical evaluation were made. Result: 48 cases of inside-out and 38 cases of outside-in cases were included. Compared to inside-out, the outside-in approach had significantly less operative time required to resect inferior articular process: 36.55 \u00b1 10.37, and total operative time: 87.45 \u00b1 20.14 min compared to 49.83 \u00b1 23.97 and 102.56 \u00b1 36.53 min, respectively, for the inside-out approach, p &lt; 0.05. Compared to the preoperative state, both cohorts achieved significant improvement of VAS and ODI at post-operative 1 week, 3 months and at final follow up. Both cohorts achieved statistically significant increased disc height with 5.00 \u00b1 2.87 mm, 5.49 \u00b1 2.33 mm and statistically significant improvement in coronal wedge angle with 1.76 \u00b1 1.63\u00b0, 3.24 \u00b1 2.92\u00b0 in the inside-out and outside-in approaches respectively. Conclusions: Complete removal of inferior articular process is the key part of endoscopic fusion with two methods that can be applied: an inside-out approach or an outside-in approach. Comparing both techniques, the outside-in approach has a shorter operative time required for inferior articular process resection and total length of operation with similar good clinical and radiological outcomes.<\/jats:p>","DOI":"10.3390\/brainsci11091169","type":"journal-article","created":{"date-parts":[[2021,9,6]],"date-time":"2021-09-06T13:09:25Z","timestamp":1630933765000},"page":"1169","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Evaluation of Two Methods (Inside-Out\/Outside-In) Inferior Articular Process Resection for Uniportal Full Endoscopic Posterolateral Transforaminal Lumbar Interbody Fusion: Technical Note"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5361-5234","authenticated-orcid":false,"given":"Hyeun-Sung","family":"Kim","sequence":"first","affiliation":[{"name":"Spine Surgery, Nanoori Gangnam Hospital, Seoul 06048, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pang-Hung","family":"Wu","sequence":"additional","affiliation":[{"name":"Spine Surgery, Nanoori Gangnam Hospital, Seoul 06048, Korea"},{"name":"Orthopaedic Surgery, JurongHealth Campus, National University Health System, Singapore 609606, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jin-Woo","family":"An","sequence":"additional","affiliation":[{"name":"Nanoori Hospital Spine And Joints Clinic, Dubai 66566, United Arab Emirates"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yeon-Jin","family":"Lee","sequence":"additional","affiliation":[{"name":"Spine Surgery, Nanoori Gangnam Hospital, Seoul 06048, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun-Hyung","family":"Lee","sequence":"additional","affiliation":[{"name":"Spine Surgery, Nanoori Gangnam Hospital, Seoul 06048, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Myeong-Hun","family":"Kim","sequence":"additional","affiliation":[{"name":"Spine Surgery, Nanoori Gangnam Hospital, Seoul 06048, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Inkyung","family":"Lee","sequence":"additional","affiliation":[{"name":"Spine Surgery, Nanoori Gangnam Hospital, Seoul 06048, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jong-Sung","family":"Park","sequence":"additional","affiliation":[{"name":"Spine Surgery, Nanoori Gangnam Hospital, Seoul 06048, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun-Hyung","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Chosun University School of Medicine, Gwangju 61452, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun-Hwan","family":"Park","sequence":"additional","affiliation":[{"name":"Neurosurgery Department, Medical School University, 4032 Debrecen, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Il-Tae","family":"Jang","sequence":"additional","affiliation":[{"name":"Spine Surgery, Nanoori Gangnam Hospital, Seoul 06048, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6","DOI":"10.14245\/ns.1836322.161","article-title":"Evolution of Spinal Endoscopic Surgery","volume":"16","author":"Kim","year":"2019","journal-title":"Neurospine"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"S3","DOI":"10.14245\/ns.2040188.094","article-title":"Development of Endoscopic Spine Surgery for Healthy Life: To Provide Spine Care for Better, for Worse, for Richer, for Poorer, in Sickness and in Health","volume":"17","author":"Kim","year":"2020","journal-title":"Neurospine"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"305","DOI":"10.1007\/s00701-019-04157-z","article-title":"How I do it? 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