Tethered cord prevalence among patients with prenatal or postnatal myelomeningocele repair

Background: Myelomeningocele (MMC) is a severe form of spina bifida characterized by spinal cord extrusion into a cerebrospinal fluid (CSF) filled sac which may lead to lifelong disability. Repair of these lesions have classically occurred shortly after birth, but more recently, prenatal myelomeningocele repair techniques have been elucidated. This study aimed to investigate the outcome of surgery, particularly with subsequent spinal cord tethering, in patients with prenatal myelomeningocele closure and those with postnatal repair surgery.

Materials and methods: In this retrospective study which assessed patients from April 2002 to April 2020, the data of 18 total patients with MMC were reviewed. Nine patients from each group were included, closed prenatally or postnatally, respectively. Demographic information including age and sex, birth week, infant comorbidities, presence of dermoid or lipoma, cutaneous stigmata, total number and timing of detethering procedures, presence of Chiari malformation, and need for VPS was obtained.

Results: Eighteen patients including nine infants closed prenatally and nine infants with myelomeningoceles closed postnatally were reviewed. The mean age was 4 ± 3 years and 6.22 ± 2.4 in prenatal and postnatal retrospectively. There was a significant relationship between the number of detethering procedures (p-value = 0.03) and the need for a ventriculoperitoneal shunt (VPS) (p-value = 0.01) between the groups, with the prenatal closure group having lower rates of each. There was no significant difference between the groups in regard to the mean age at the detethering procedure (p = 0.4), sex (p = 0.09), birth week (p = 0.8), comorbidities (p = 0.8), presence of intraspinal dermoid or lipoma (p = 0.09), presence of cutaneous stigma (p = 0.08), Chiari (p = 0.6), fatty filum (p = 0.08), syrinx (p = 0.4), bone anomaly (p = 0.4), and spina bifida neurological scale (p = 0.66).

Conclusion: There was a significant relationship between the two groups in terms of the number of detethering procedures, and the need for VPS. Our data represents a possible difference in the need for detethering surgeries and ventriculoperitoneal shunt placements between patients with prenatal and postnatal myelomeningocele closures.