[A case of late-onset tethered cord syndrome presenting with spastic paraparesis]

We report a patient with late-onset tethered cord syndrome who presented with slowly progressive spastic paraparesis. Final diagnosis was made with spinal MRI. A 55-year-old man developed disturbance in gait at 52 years. He had severe congenital scoliosis of the thoracic spine and skin anomaly and hypertrichosis in the midline of the sacral region. His feet revealed pes equinovarus and pes cavus. Deep tendon reflexes in the lower extremities were hyperactive with positive Babinski signs. Vibration sense was diminished in the lower extremities. He had sexual impotence but no vesical or rectal disturbances. The plain X-rays revealed scoliosis at the fourth and fifth thoracic vertebrae, multiple costal fusion from the fourth through the eighth ribs on the left, and spina bifida occulta at the lumbosacral vertebrae. On MRI, the conus was tethered downward at the level between the forth and fifth vertebral bodies, and a thickened filum terminale connected the conus with a coccygeal cyst. Tethered cord syndrome, though rare in adults, should be differentiated from other diseases which produce late-onset spastic paraparesis, and MRI of the lumbo-sacral region is very useful for its diagnosis.