Exploring Physical Lumbar Microvascular Geometry Through Endoscopy and Illustrations: Implications for Clinical Interpretation.

Abstract

Retrospective Study. Minimally invasive endoscopic spinal surgery is gaining popularity, but our understanding of the lumbar spine's microvascular geometry relies heavily on cadaver studies and textbook illustrations. Additionally, inconsistent nomenclature of vessels in the literature hampers effective communication among surgeons. This study aims to improve the clarity and comprehensibility of the lumbar spinal microvascular geometry under endoscopic view. The study included 400 patients who underwent endoscopic spinal surgery for lumbar spinal canal stenosis and foraminal stenosis. The surgeries were performed by an experienced surgeon using either the interlaminar or transforaminal approach. Endoscopic video recordings were further analyzed to map the microvascular geometry and common bleeding foci. The observed results were cross-referenced with existing literature to reconstruct a comprehensive view of the vascular anatomy. The transforaminal approach commonly encounters bleeding foci originating from the major branches of the segmental lumbar artery and the emissary veins within the foramen. The interlaminar approach primarily encounters bleeding foci from the muscle vessels in the dorsal lamina, which are believed to be located near the ends of the three main branches. In the intracanal region, epidural vessels form a rotary loop above the disc, which can contribute to most of the bleeding during discectomy. This study provides a comprehensive understanding of the microvascular anatomy in the lumbar spine during endoscopic spinal surgery. Recognizing the geometry will help surgeons anticipate and control bleeding, reducing the risk of complications. The findings contribute to the improvement of surgical techniques and patient safety in endoscopic spinal surgery.