Characteristics of repeated untethering pattern in patients with myelomeningocele from infancy to adolescence

Radiological evidence of secondary spinal cord tethering has been observed in patients with myelomeningocele (MMC), even after primary surgical treatment. A significant number of these patients may develop symptomatic tethered cord syndrome (TCS) several times during the clinical course, with worsening of preexisting neurological deficits, or bladder or bowel function. Early untethering is necessary to prevent further progression of symptoms. The aim of this study was to investigate factors influencing postoperative outcome of spinal cord untethering (SCU) on recurrent TCS.

A retrospective analysis was conducted in a cohort of 156 patients with MMC treated between January 1990 and March 2025. Indications for SCU, perioperative data on neurosurgical interventions, postoperative complications, and clinical-neurological outcomes were analyzed.

After primary closure (n = 156), 43% of patients (n = 67) with MMC required at least 1 SCU. A total of 91 SCUs were performed in 67 patients in whom 10 years of follow-up was available. Among those, 30 developed another TCS while 61 remained neurologically stable. After the age of 15 years, the risk of SCU decreased. An increased risk of secondary SCU intervention was found in those individuals with either a postoperative epidural CSF collection (hazard ratio [HR] 3.9, 10-year survival rate; p = 0.02) or a lack of intraoperative neurophysiological monitoring (IONM) used during SCU (HR 2.3, 10-year survival rate; p = 0.03) as negative prognostic factors.

To achieve timely intervention, it is essential to implement multidisciplinary patient management and early recognition of TCS. Surgical experience is relevant to avoid possible complications with SCU if intervention is indicated. IONM is a valuable technique in the surgical management of secondary TCS as it appears to reduce the risk of repeated surgery.