Spinal dural attachments to the vertebral column: An anatomic report and review of the literature

BACKGROUND The spinal dura is anchored within the vertebral canal by connective tissue in the epidural space as well as the spinal roots. Inadvertent disruption of these dural attachments may lead to durotomy and cerebrospinal fluid (CSF) leaks. We observed well-developed connective tissue ligaments connecting the lumbar dura to the spinal column and examined these tissues microscopically. METHODS Intraoperative images were obtained during lumbar laminectomy procedures. They demonstrated connective tissue attachments, linking the lumbar dura to the spinal column in the dorsal midline and dorsolaterally. Tissue samples were obtained and examined microscopically. We then conducted a search of the literature to find references to dural attachments to the spinal column. RESULTS Histological examination of the samples showed minimal cellular fibrous tissue. To date no references to these attachments have been made in neurosurgical literature. Previous studies, including live, cadaveric, and radiographic examinations, have demonstrated a dorsomedian fold of dura attached to the junction of the ligamentum flavum, and dorsolateral ligaments that divide the dorsal epidural space into an anterior and posterior compartment. CONCLUSIONS Epidural fibrous connections or ligaments between the dura and the lumbar spinal column may be of clinical importance to the neurosurgeon. Care should be taken during lumbar procedures not to disrupt or tear these ligaments as this may cause dural tears and CSF leaks. Identifying these ligaments and cutting them sharply may prevent inadvertent durotomies.