The Morphology and Clinical Significance of the Dorsal Meningovertebra Ligaments in the Lumbosacral Epidural Space

Abstract

In Brief Study Design. A dissection-based study of 30 embalmed cadavers. Objective. To determine the morphology and morphometry of the dorsal meningovertebral ligaments in the lumbosacral segments and to discuss their clinical significance. Summary of Background Data. Postoperative cerebrospinal fluid leakage is associated with longer hospital stays and significant implications for the patient, the surgeons, and society as a whole. To protect the dural sac during lumbar surgery, knowledge of the surgical anatomy of the dorsal meningovertebral ligaments is crucial. Methods. A total of 30 adult embalmed cadavers (52–70 yr of age; mean age of 64 yr) were used. The vertebral canal was divided to expose the dural sac and the spinal nerve roots, and the spinal cord was removed. The morphology, quantity, and attachment of the dorsal meningovertebral ligaments in the lumbosacral region were observed, and the length, width, or diameter and thickness of the ligaments were measured with vernier calipers. Results. The dorsal meningovertebral ligaments in the lumbosacral region connect the dura to the ligamenta flava or the lamina. The number of the attachment points on the ligamenta flava was relatively larger than that on the lamina, and the occurrence rate of dorsal meningovertebral ligaments was 97% at L5–S1. The thickest ligaments were observed at the L5 and S1 vertebrae. The length of the ligaments varied from 5.16 to 40.24 mm, and the ligaments extended caudally from their origin on the dura to their attachment to the lamina or the ligamentum flavum. The morphology of the dorsal meningovertebral ligaments was divided into 5 types: strip type, cord type, “Y”-shaped type, grid type, and thin slice type. Conclusion. The dorsal meningovertebral ligaments may contribute to dura laceration and epidural hemorrhage during flavectomy and laminectomy, and an appreciation of this relationship might help reduce the risk of such complications. A total of 30 cadaveric pelvic specimens were investigated. The morphology and morphometry of the dorsal meningovertebral ligaments in the lumbosacral segments were described and analyzed. This study suggests that the structure of these ligaments may be the anatomical factor that determines the occurrence of dura laceration and epidural hemorrhage, and it might be beneficial for surgeons to become familiar with their anatomy through gross anatomical dissections prior to performing lumbar surgery.