Related Experiment Video
Updated: Jun 27, 2025

Uniportal Full Endoscopic Posterolateral Transforaminal Lumbar Interbody Fusion
Published on: June 6, 2025
Imaging anatomy study related to unilateral biportal endoscopic lumbar spine surgery
Shengxuan Hu1, Jingwen Zhang1, Weibo Zeng1
1Department of Spine Surgery, Zhujiang Hospital, Southern Medical University, 253 Gongye Road, Guangzhou, 510282, China.
Purpose:
To provide lumbar spine anatomical parameters relevant to the UBE technique and explore their intraoperative application.
Methods:
CT imaging data processed by Mimics for parametric measurements, including laminar abduction angle (LAA), laminar slope angle (LSA), minimum laminar height (MLH), distance between the inferior margin of the lamina and attachment of the ligamentum flavum onto the cephalad lamina (DLL), distance between the initial point and the middle of the articular process (DIA), and distance from the inferior margin of the lamina to the inferior border of the vertebral body (DLV), and were manually measured.
Results:
LAA and DIA gradually increase from L1 to L5. At L1, the DIA is approximately the length of 2 drill bits with a diameter of 3 mm (male: 7.77 ± 1.39 mm, female: 7.22 ± 1.09 mm), while at L5, it can reach the length of 4-5 drill bits (male: 14.96 ± 2.24 mm, female: 13.67 ± 2.33 mm). MLH, DLL, and DLV reach their maximum values at the L3 and decrease toward the cranial and caudal ends. The DLL is smallest at L5 (male: 9.58 ± 1.90 mm, female: 9.38 ± 2.14 mm), equivalent to the length of 3 drill bits, while the DLL at L3 is the length of 4-5 drill bits (male: 14.17 ± 2.13 mm, female: 14.01 ± 2.07 mm).
Conclusion:
Referring to the drill diameter during surgery can mark the extent of laminotomy. The characteristics of vertebral plate angles at different lumbar levels can provide references for preoperative incision design.

