Adult Type II diastematomyelia with tethered cord and associated spinal anomalies: A case report

Abstract

Spinal dysraphism consists a group of congenital anomalies due to defective neural tube closure, among which diastematomyelia or split cord malformation is rare. Split cord malformation is classified into Type I and Type II, with Type II being less common and often asymptomatic. These anomalies may coexist with various spinal anomalies, as tethered cord, neural lipoma, hemimyelocele, and dorsal dermal sinus, forming a complex spectrum. Adult presentations are particularly uncommon and usually incidental. We herein report a 23-year-old male with chronic low back pain and a congenital midline lumbar swelling. Neurological examination and routine investigations were unremarkable. Magnetic resonance imaging revealed Type II diastematomyelia with two hemicords within a single dural sac from L4 to L5, low-lying conus medullaris, hemimyelocele with neural lipoma at L5-S1, tethered cord with filum terminale lipoma extending to S3-S4, and a dorsal dermal sinus tract. Despite the radiological complexity, the patient remained neurologically intact. Neurosurgical intervention was advised; however, the patient chose conservative management with close follow-up. This case highlights a rare adult presentation of complex spinal dysraphism with minimal symptoms. While diastematomyelia Type II is typically diagnosed in childhood, adult cases are infrequent and often delayed. Magnetic resonance imaging is crucial for diagnosis, particularly in asymptomatic individuals with cutaneous markers. Though surgery is generally recommended to prevent neurological decline, conservative management may be appropriate in selected stable cases. This case emphasizes the need to consider spinal anomalies in adults with chronic back pain and the importance of multidisciplinary evaluation.