Embryology and classifications of spinal cord lipomas (literature review)

Lumbosacral lipomas are congenital spinal malformations caused by defects in primary and secondary neurulation during embryogenesis, leading to tethered spinal cord syndrome and neurological deficits. Understanding the embryological development and pathogenesis of these lipomas is crucial for improving surgical outcomes. Embryogenesis involves primary neurulation, where the neural plate forms and folds into the neural tube, and secondary neurulation, where the medullary cord forms and differentiates into the conus medullaris and filum terminale. Disruptions in these processes can result in lumbosacral lipomas. The premature disjunction theory suggests that early ectoderm separation allows mesenchymal invasion, while dorsal induction disorders and secondary neurulation defects involve mesodermal elements disrupting normal development, leading to lipomatous tissue tethering the spinal cord. The classification systems by Chapman, Arai, and Pang categorize lumbosacral lipomas based on anatomical and embryological features, aiding in surgical planning and prognosis. These classifications help neurosurgeons determine the complexity and associated risks of lipomas, guiding surgical techniques to minimize complications and improve outcomes. Understanding these classifications and the underlying embryology is essential for advancing treatment and patient care.