Incidence of symptomatic tethered spinal cord in pediatric patients presenting with neurofibromatosis types 1 and 2.

OBJECTIVE The relationship between a tethered cord (TC) and neurofibromatosis type 1 (NF1) and NF2 is not known. The purpose of this study was to define the incidence of TC in pediatric neurosurgical patients who present with NF. METHODS The authors performed a single-institution (tertiary care pediatric hospital) 10-year retrospective analysis of patients who were diagnosed with or who underwent surgery for a TC and/or NF. Clinical and radiological characteristics were analyzed, as was histopathology. RESULTS A total of 424 patients underwent surgery for a TC during the study period, and 67 patients with NF were seen in the pediatric neurosurgery clinic. Of these 67 patients, 9 (13%) were diagnosed with a TC, and filum lysis surgery was recommended. Among the 9 patients with NF recommended for TC-release surgery, 4 (44%) were female, the mean age was 8 years (range 4-14 years), the conus position ranged from L1-2 to L-3, and 3 (33%) had a filum lipoma, defined as high signal intensity on T1-weighted MR images. All 9 of these patients presented with neuromotor, skeletal, voiding, and/or pain-related symptoms. Histopathological examination consistently revealed dense fibroconnective tissue and blood vessels. CONCLUSIONS Despite the lack of any known pathophysiological relationship between NF and TC, the incidence of a symptomatic TC in patients with NF1 and NF2 who presented for any reason to this tertiary care pediatric neurosurgery clinic was 13%. Counseling patients and families regarding TC symptomatology might be indicated in this patient population.