A Patient with a Type I Split Cord Malformation and an Open Myelomeningocele without Advanced Lower Limb Paresis: A Case Report and a Review of the Literature.

We report a rare case of a split cord malformation (SCM) combined with an open myelomeningocele (MMC) on the right hemicord. The patient was a male neonate, who exhibited an MMC in the lumbosacral region at birth. Both of his lower limbs moved with slight spasticity, but no atrophic changes or clubfoot deformities were seen. Three-dimensional computed tomography (CT) demonstrated a bony septum, and the patient was diagnosed with a type I SCM. Magnetic resonance imaging (MRI) showed an MMC on the right hemicord (a hemimyelomeningocele). The repair of the open MMC and the removal of the septum were performed immediately to prevent infection and neurological deterioration. Intraoperatively, the right hemicord was thinner than the left hemicord. No additional neurological deficits or complications appeared during treatment. Our findings suggest that when a minor hemicord is affected by both an SCM and an open MMC, good functional outcomes of the lower limbs can be achieved.