L-Point Entry, Juxtapedicular, and Endplate-Parallel Trajectory (L-JET) Screw Fixation: A Novel Technique in Thoracic Spinal Tumor Surgery
10.21182/jmisst.2025.02446
- Author:
Seunghoon LEE
1
;
Young Rak KIM
;
Chang-Hyun LEE
;
Jungbo SIM
;
Woojin KIM
;
Ho Sung MYEONG
;
Hangeul PARK
;
Jun-Hoe KIM
;
Chi Heon KIM
Author Information
1. Department of Neurosurgery, Seoul National University Hospital, Seoul, Korea
- Publication Type:Original Article
- From:
Journal of Minimally Invasive Spine Surgery and Technique
2026;11(1):6-13
- CountryRepublic of Korea
- Language:English
-
Abstract:
Objective:Thoracic pedicle screw fixation is technically demanding because of the natural variability in pedicle anatomy, a challenge that is further exacerbated in patients with spinal tumors who often have compromised pedicles. The L-point entry, juxtapedicular, and endplate-parallel trajectory (L-JET) technique was developed to provide a uniform entry point, a predictable screw trajectory, and the capacity to accommodate larger-diameter screws at levels T3–10. This study aimed to evaluate the safety and feasibility of the L-JET technique in comparison with the conventional transpedicular method.
Methods:A comparative analysis of consecutively collected data was performed to evaluate outcomes associated with the L-JET technique in patients undergoing surgery for thoracic extradural spinal tumors. The L-point was defined as the intersection of a vertical line along the lateral margin of the facet joint and a horizontal line along the upper edge of the transverse process. The screw trajectory was planned with 30° of medial convergence in the axial plane, creating a juxtapedicular path, and a straightforward trajectory in the sagittal plane. Primary outcome measures included screw diameter, screw length, cortical breach rate, and the need for revision surgery, as assessed using computed tomography scans and medical records.
Results:A total of 108 screws were placed in 22 patients using the L-JET technique, while 98 screws were placed in 18 patients using the conventional technique. The L-JET group used significantly larger-diameter screws (6.06±0.65 mm) than the conventional group (5.74±0.80 mm, p=0.02), with no significant difference observed in screw length between groups. Medial cortical breach occurred in one screw in each group, and no supra- or infrapedicular breaches were identified. No screw-related neurovascular complications or revision surgeries occurred in either group.
Conclusion:The L-JET technique enables consistent screw placement with larger-diameter screws, even in compromised pedicles associated with thoracic spinal tumors, without increasing the risk of complications or the need for revision surgery.
