Fluoroscopically Guided Interventional Transforaminal Needling for Lumbar Instability using a Specially Designed Needle Conjoining Epiduroscopic Evaluation: An Exploratory Study

Objective: Spinal instability is a major cause of low back or radicular pain. We developed an interventional procedure to manage pain resulting from lumbar instability using a specially designed needle. This study describes the methodological approach and clinical application of the procedure. Methods: A cadaveric study was conducted to develop an approach route for the needle. After developing an approach route, the technique was applied clinically to patients with lumbar instability (n = 15). The patients underwent epiduroscopy before undergoing the procedure to evaluate the epidural space findings related to lumbar instability. A specially designed curved Round Needle was inserted 8‑12 cm lateral to the midline, one level above the target. The needle was advanced to the facet joint and moved forward and backward within a range of a few millimeters until smooth sliding was felt at the tip of the needle. It was advanced in a medial and caudal direction along the facet joint and superior articular process. When the needle accessed the interface between the posterior longitudinal ligament and annulus fibrosus in the lateral recess, below the inferior end plate, it was moved forward and backward within a range of a few millimeters again until smooth sliding was felt at the tip of the needle. Results: After the patients underwent the intervention, outcome measures in this study (visual analog scale pain score, EQ-5D index, and self-rated improvement following intervention compared with initial state) improved significantly at the 2- and 6-month followup evaluations. Conclusion: This study suggests that fluoroscopically guided interventional transforaminal needling has clinical significance in managing pain resulting from lumbar instability.