Advanced neurosurgical intervention of recurrent tethered cord syndrome with split cord malformation type 1: an illustrative case

PURPOSE: Recurrent tethered cord syndrome (TCS) with split cord malformation (SCM) is a rare presentation with distinct surgical challenges to successful patient outcomes. SCMs are rare and can progress to cause significant neurological deficits including pain, weakness, sensory disturbance, bowel and/or bladder dysfunction. In these circumstances, surgical management of TSC with SCM is indicated. Reoperation for recurrent TCS, particularly in the context of retained or regrown bony septa and prior spinal instrumentation, is technically demanding and carries elevated risk. ILLUSTRATIVE CASE: This case presents a 26-year-old woman with recurrent TCS and SCM Type I who previously underwent multiple spinal surgeries, including posterior spinal fusion and partial resection of a bony septum. She developed progressive radiculopathy, neurogenic bladder, and recurrent urinary tract infections despite conservative therapy. Advanced imaging revealed a recurrent bony septum and tethered neural elements. A two-stage surgical approach was undertaken: first, anterior spinal hardware was removed via thoracoabdominal exposure due to impingement on the hemicord; second, a complex posterior tethered cord release (TCR) was performed with resection of the recurrent bony septum, microsurgical detethering, and resection of the medial dura between hemicords. Intraoperative neuromonitoring and careful neuroanatomic dissection were critical to preserve function and minimize risk. Postoperatively, the patient demonstrated marked improvement in lower extremity pain, mobility, and bladder control. CONCLUSIONS: This case underscores the complexity of managing recurrent TCS with SCM Type I, particularly when prior surgery is incomplete or complicated by spinal instrumentation. Key technical considerations include removal of the bony septum, resection of the medial dura to prevent recurrence, and careful dissection through scarred neural tissue. Preoperative planning with multidisciplinary coordination and intraoperative neurophysiological monitoring is essential to optimize outcomes. This report contributes to the limited literature on recurrent SCM management in adults and reinforces the importance of complete initial intervention and longitudinal follow-up in complex spinal dysraphisms.