Evaluation of Two Methods (Inside-Out/Outside-In) Inferior Articular Process Resection for Uniportal Full Endoscopic Posterolateral Transforaminal Lumbar Interbody Fusion: Technical Note

• Published in: Brain sciences 2021-09, Vol.11 (9), p.1169
• Main Authors: Kim, Hyeun-Sung, Wu, Pang-Hung, An, Jin-Woo, Lee, Yeon-Jin, Lee, Jun-Hyung, Kim, Myeong-Hun, Lee, Inkyung, Park, Jong-Sung, Park, Jun-Hwan, Jang, Il-Tae
• Format: Article
• Language: English
• Subjects: Back surgery; Degenerative disc disease; degenerative spine disease; Dissection; Drilling; endoscopic lumbar interbody fusion; endoscopic spine surgery; Endoscopy; Intervertebral discs; minimally invasive spine surgery; Patients; spinal fusion; Spinal stenosis; Statistical analysis; transforaminal lumbar interbody fusion; Vertebrae
• ISSN: 2076-3425; 2076-3425
• DOI: 10.3390/brainsci11091169

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 ± 10.37, and total operative time: 87.45 ± 20.14 min compared to 49.83 ± 23.97 and 102.56 ± 36.53 min, respectively, for the inside-out approach, p < 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 ± 2.87 mm, 5.49 ± 2.33 mm and statistically significant improvement in coronal wedge angle with 1.76 ± 1.63°, 3.24 ± 2.92° 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.