Lipoma of the conus: A study about 546 children from the neurosurgical care to a physical and rehabilitation medicine management

Abstract

Lipoma of the conus is the most frequent occult spinal dysraphism. For children with lipoma of the conus, the evolution of the symptoms remains unclear. The convention that prophylactic surgery improves outcome is discussed for the last twenty years. The aims of this work are to describe the symptoms and the natural history with or without surgery of this malformation and to highlight some prognostic factors. The children were included if they were followed by a neurosurgeon (hôpital Necker–Enfants-Malades, Paris) and a rehabilitation doctor (hôpital Armand-Trousseau, Paris). The study was retrospective from 1970 to 1995 then prospective to 2013. A total of 546 patients with lipomas of the conus were recruited. The sex-ratio is 1.24 for girls. The first symptoms appeared most commonly before the five years old. The most frequent symptoms are constipation and fecal incontinence. The bladder dysfunctions have the biggest impact on the social life of the children. Following the neurosurgery, the neurologic deterioration has continued for 12% of the patients. After 1995, 217 children without symptoms at the first consultation went to surgery only if neurological signs appeared. During the follow up, 91% of those patients remained asymptomatic. The prognostic factors we find are: the lipoma size, a very low conus medullaris position, nerve roots malformations and difficulties to obtain total or near-total resection lipoma. After the diagnosis done, the surveillance has to be continued for asymptomatic patients. Neurosurgery is proposed only if symptoms appeared. Management of neurologic bowel and bladder is to obtain a vesicle and fecal continence adapted to the age of the child. The renal function and the integrity of bladder wall is protected with regular and complete bladder emptying with low pressure. The orthopedic problems are foot malposition, which can needed orthosis. The frequency and the severity of the urinary and bowel dysfunctions alone require a physical and rehabilitation medicine follow-up.