Objective: Biportal endoscopic spine surgery (BESS) has emerged as a minimally invasive alternative for lumbar decompression, offering improved visualization with reduced tissue disruption. Therefore, this study aims to identify key anatomical considerations, particularly interlaminar-disc mismatch and the “banana-shaped” curvature of the lamina, and to examine their impact on portal trajectory, alignment of the surgical corridor, and preservation of spinal structures. Methods: A retrospective, video-based analysis was conducted on 23 BESS lumbar decompression cases performed between January and March 2024. Surgical levels included L3–4 (n=3), L4–5 (n=17), and L5–S1 (n=3). Intraoperative anatomical landmarks were assessed independently by 2 spine surgeons. Interobserver agreement was evaluated using Cohen kappa, based on the identification of 3 landmarks per case in 23 cases, calculated with unweighted kappa. Visualization quality was scored on a 3-point scale. Cranial and caudal interlaminar-disc mismatches were measured and averaged. Results: Interlaminar-disc mismatch was identified in 93% of cases, with cranial and caudal mismatches ranging from 5.5±1.02 mm to 8±1.2 mm. Laminar curvature was consistently observed at L4–5 and L5–S1, which required a medial-caudal portal. In addition, the superior articular process (SAP) served as a reliable fluoroscopic and endoscopic landmark, facilitating safe access to the intervertebral disc. A limited medial facetectomy provided adequate operating space. The findings also demonstrated high interobserver reliability for anatomical identification (κ=0.84), and the use of layer-specific flavectomy preserved the inner layer of the ligamentum flavum. Conclusion Successful BESS requires integrating detailed anatomical understanding with intraoperative adaptability. Recognizing interlaminar-disc mismatch, laminar curvature, and SAP orientation enables optimal portal placement and targeted decompression. These principles are essential for achieving reproducible and safe outcomes in BESS.

Background: pinal epidural abscess (SEA) is a rare disease, difficult to detect, high defect rate, and can be lifethreatening. It is characterized by accumulation of pus in the epidural space causing suppression of the spinal cord and spinal roots. This study will describe a case of a 35-year-old man with SEA in Indonesia. Case presentation: A 35-year-old male with pain in the lumbar region 1, radicular pain according to thoracic dermatome 10, flaccid inferior paraplegia, hypoesthesia as high as thoracic dermatome 10, and retention of alviet uri due to SEA caused by Staphylococcus pseudintermedius confirmed by abscess culture. Management of this patient was through an operation, debridement, and administration of antibiotic. Conclusion This patient was diagnosed with SEA from anamnesis, physical examination, laboratory finding, and radiology finding. This case is rarely found and is a big problem for neurologists due to the difficulty of early diagnosis.
Pain