Split cord malformation associated with spinal open neural tube defect

OBJECTIVE: To illustrate the clinical and radiological findings of split cord malformation (SCM) in patients with spinal open neural tube defect (SONTD), and report the outcome of their treatment.

METHODS: A retrospective study of the clinical and radiological findings of 11 patients diagnosed with SCM, identified among 83 patients with SONTD at King Khalid University Hospital, in Riyadh, Saudi Arabia between 1995 and 2010.

RESULTS: There were 6 girls and 5 boys; their age ranged from less than a year to 9 years (mean 4.2 years). Six patients had type I SCM, and 5 patients type II SCM. The CT and MRI imaging showed characteristic bony, cartilaginous, or fibrous septum, and other SONTD-associated anomalies. Seven patients were graded A & B according to the Frankel grading score, and none of them required surgery, while worsening neurology led to surgical intervention in 3 patients, with clinical improvement after surgery, and one patient that underwent cord untethering remained stable.

CONCLUSION: Split cord malformation is not uncommon among patients with SONTD. It tends to involve mainly the lumbar spine, and female predominance is more remarkable in type I. Neurological manifestations of SCM may be superimposed with SONTD. Surgery is effective for symptomatic patients, and not indicated in the severely disabled.