Anatomy of the spinal cord with meningomyelocele and tethered cord symptoms

This chapter describes the anatomy of the spinal cord in children born with meningomyelocele, and reviews co-morbidities following the primary repair of meningomyeloceles. Data from 654 cases of meningomyelocele have been drawn from a computerized database, Patient Data Management System/fx [16]. We have also performed computer-assisted analysis of magnetic resonance imaging (MRI) studies of the spinal cord. This chapter describes the anatomy of the spinal cord of 41 patients examined by 67 MRI studies from a total of 83 patients. All cases were selected because they experienced symptoms compatible with a tethered cord and had had a neurosurgical procedure. An additional five were diagnosed with spinal cord hypoplasia. Tethered cord symptoms were related to local scarring, and improved following surgical release for 62 of the 83 postmeningomyelocele repair patients. Of the symptoms of the other 21 patients, 16 were relieved by other operations (e.g., CSF shunt repair) and five were not subjected to an untethering procedure because of a diagnosis of spinal cord hypoplasia. Etiologies other than, or in addition to, tethering included an obstructed cerebrospinal fluid shunt, syringohydromyelia, and benign tumor, as well as spinal cord hypoplasia. The areas of spinal cords were determined from axial MRI by digitized cross sections of 23 vertebral levels of the 41 patients and five normal controls. These studies differentiated very small, symptomatic spinal cords from the spinal cords of symptomatic and asymptomatic syringohydromyelia as well as from spinal cords of patients with spinal cord tethering. Collaborative, multicenter studies of larger numbers of patients are recommended.