Occult filum terminale syndrome.

Thirty-two pediatric patients presenting with symptoms of urinary dysfunction, stool incontinence and/or severe back and/or leg pain are described. In patients with urological dysfunction, urodynamic testing was consistent with a neurogenic etiology. Imaging studies demonstrated the tip of the conus medullaris to lie above the L2 vertebral body, and the filum terminale to be of normal diameter ( < 2 mm) in all patients. A diagnosis of an occult filum terminale syndrome was made based on clinical presentation in the absence of associated imaging abnormalities and section of the filum terminale was performed. Postoperatively, the majority of patients (97%) experienced significant ( > 50%) relief of their symptoms. The management of these patients is discussed.