Morphological features of the lumbosacral spinal lipomas with special reference to clinical symptoms and surgical outcome in children

Abstract

Introduction: The shape and structures surrounding lumbosacral spinal lipoma have a variety of morphologies, including neural tissues and the dural sac. In determining how best to manage lumbosacral spinal lipomas, it is necessary to compare the natural course of the disease and the outcomes associated with surgery (e. g., incomplete untethering, the risk of surgical complications and the remaining risk of retethering). In this study, we compared the morphological implications associated with the natural course and operative results in patients with lipoma. Methods Thirty-four consecutive patients with spinal lipomas (20 cases of conus lipomas and 14 cases of filum lipomas), aged 0 months to 13 years, were studied retrospectively. We analyzed the association of 3 morphological features-protrusion of the spinal cord from the spinal canal, widespread adhesion between the spinal cord and lipoma, and abnormal exit of the nerve root from the dural sac-with preoperative symptoms and surgical outcomes. Results Preoperative symptoms of conus lipomas were more significantly associated with the existence of any of the 3 morphological features (92%) than their absence (0%) (p<0.05). Surgical outcomes for conus lipomas, such as incomplete untethering, neurological complications, and remaining narrow subarachnoid space, were more significantly associated with the existence of any of the 3 morphological features (46%) than their absence (0%) (p<0.05). None of the 3 morphological features were observed in patients with filum lipomas. Preoperative MRI demonstrated spinal cord herniation and widespread adhesion of the lipoma in all of the patients with these morphologies but failed to demonstrate abnormal root exits in 50% of the patients. Conclusion The morphological features of the spinal lipomas presented in this study may be important factors for predicting the difficulty of untethering surgery and the clinical course of conus lipomas.