Lumbar spinal stenosis (LSS) is a common degenerative spinal condition where spinal canal narrowing causes symptoms such as neurogenic claudication, radiculopathy, and lower back pain. While non-operative and surgical approaches yield similar long-term outcomes, surgical intervention—particularly decompression—can provide earlier symptom relief, functional recovery, and fall prevention in selected patients with refractory symptoms. Recent advancements in surgical technologies and image guidance have brought about a paradigm shift in LSS management. Biportal endoscopic spine surgery (BESS) has gained global traction as a minimally invasive alternative to traditional decompression methods, offering superior visualization, less soft tissue damage, shorter hospital stays, and faster recovery. High-quality studies, including randomized controlled trials, have shown promising outcomes for this technique. Furthermore, the integration of navigation systems, robot-assisted instrumentation, and artificial intelligence (AI)-driven diagnostics and surgical planning tools is transforming spinal surgery by enhancing precision in preoperative evaluation and intraoperative execution. These innovations enable accurate targeting, reduce complications, and improve reproducibility across diverse surgical settings. This review provides an updated overview of LSS, covering its pathophysiology, clinical assessment, diagnosis, and treatment. Special emphasis is placed on the growing role of BESS and the transformative impact of digital technologies such as navigation, robotics, and AI in the evolving landscape of spinal stenosis care.

Objective: Implant fixation in osteoporotic bone presents substantial challenges due to reduced bone mass and compromised microarchitecture. This study investigated whether romosozumab, a sclerostin inhibitor, improves osseointegration and mechanical stability of cancellous bone screws in glucocorticoid-induced osteoporosis.Methods: Fifty-five New Zealand white rabbits were enrolled. Osteoporosis was induced via either bilateral ovariectomy or weekly intramuscular glucocorticoid injections (4–8 mg/kg). Based on bone mineral density results, glucocorticoid injection was selected for experimental induction. Rabbits were divided into 5 groups: control, untreated osteoporosis, parathyroid hormone (PTH), PTH combined with denosumab, and romosozumab. Cancellous bone screws (4.0-mm diameter, titanium alloy) were bilaterally inserted into the iliac bones. Antiosteoporosis treatments were administered for 3-week postimplantation. Histomorphometric evaluation of bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) was performed using nondecalcified sectioning and Goldner trichrome staining. Biomechanical pull-out testing measured resistance at 1-mm displacement using a standardized setup on the MTS system.Results: The romosozumab-treated group exhibited superior outcomes. BIC reached 21.2%±18.1%, and BAFO was 56.9%±9.9%. Pull-out strength significantly increased to 275±55 N in the romosozumab group, outperforming PTH (184±61 N), PTH+denosumab (202±23 N), and untreated osteoporosis (120±33 N). Enhanced collagen structure and neobone formation were observed histologically around implants.Conclusion: Romosozumab significantly enhances cancellous bone screw fixation strength and osseointegration in glucocorticoid-induced osteoporotic bone. These findings suggest its clinical potential as an adjuvant therapy in improving spinal implant outcomes in osteoporotic patients.

Kim N, et al. Clin Orthop Surg. 2023 Apr;15:e22. https://doi.org/10.4055/cios22387

Background/Objectives: This is a retrospective study. We aimed to identify an optimal biportal endoscopic spine surgery (BESS) technique that maximizes facet joint preservation while achieving sufficient decompression for central to extraforaminal lumbar stenosis across all spinal levels. Methods: We retrospectively analyzed the data of 46 patients who underwent surgery and assessed clinical outcomes (visual analogue scale scores for pain; pregabalin usage) and radiological changes (using computed tomography/magnetic resonance imaging) in the spinal canal; intervertebral foramen area expansion; facet joint preservation; and degenerative change. Results: Using interlaminar and transforaminal approaches (two-way BESS decompression technique), the mean facet joint volume preservation ratio was 87%, and the mean facet joint length maintenance ratio was 90%, indicating a successful anatomical preservation compared with previous studies. Radiological outcomes revealed effective decompression (178% in the spinal canal; 245% in intervertebral foramen expansion). Additionally, all clinical outcome parameters significantly improved (p < 0.001). Conclusions: To the best of our knowledge, this study is the first to accurately estimate the degree of facet joint preservation using different methods after endoscopic surgery. The two-way BESS decompression technique maximized facet joint preservation with sufficient decompression and clinically improved central to extraforaminal stenosis across all lumbar levels. Therefore, this technique can sufficiently preserve facet joints to prevent rapid degenerative change after surgery.