Real spinal cord injury without radiologic abnormality in pediatric patient with tight filum terminale following minor trauma: a case report

The patient was a 6-year-old girl who had no signs or symptoms of tethered cord syndrome prior to the minor trauma. Her father struck her hipshot with a painting pen and she performed evasive action with back bend movement. 30 min later, she could not get up again because of weakness in her legs. She complained of back pain and suffered from incontinence. On admission to the hospital 30 h after injury, she had paralysis of the lower extremities and dysfunction of two bowel movements. No signs of external wounds were found. She had no particular past history. A blood examination demonstrated no specific findings. Computed tomography (CT) of the spine showed spina bifida occulta. A spinal cord magnetic resonance imaging (MRI) performed 3 days following the injury. The sagittal MRI images showed longitudinally extended intramedullary patchy T1 hypointensity and T2 hyperintensity at the T9-L1 level. The conus was located at L1 level with moderate swelling. A nodular T1 isointensity and T2 isointensity shadow was showed at the dorsal of the cone. The next day, the patient underwent extended surgical exploration and lysis of the filum terminale. In the operation, we found 2 mm in diameter TFT with fibrous degeneration, which was confirmed by the histopathologic examination. There was contusion and laceration in the conus medullary. Some contusion and laceration tissue outflew the soft spinal meninges (Fig. 1). She remained in the hospital for 14 days. Upon discharge, the patient still complained of residual weakness and paresthesias in the lower extremities. By the 1-year follow-up, the patient still had paralysis of the lower extremities and dysfunction of two bowel movements.

A healthy 7-year-old boy danced on the bed, making back bend and front bend movements. Suddenly he felt weakness in both of his leg and fell off the bed. He could get up again. About 30 min later, he complained of numbness and weakness in the lower extremities and had incontinence. On admission to the hospital, the patient had paralysis of the lower extremities and dysfunction of two bowel movements. He had no signs or symptoms of tethered cord syndrome prior to the trauma. The patient was placed on a corticosteroid protocol. CT found spina bifida occulta. The sagittal MRI images showed longitudinally extended diffused intramedullary patchy T1 hypointensity and T2 hyperintensity at the T12-L1 level. The conus medullary was located at L1 level with mild swelling. The patient underwent extended surgical exploration and lysis of the filum terminale. Contusion in the conus medullary and 2 mm in diameter TFT with fibrolipoma was found in the operation. The fibrolipoma of the filum terminale was confirmed by histopathology (Fig. 2). Upon discharge, the patient still had paralysis of the lower extremities and incontinence. By the 10-month follow-up, the patient’s left leg muscle strength improved to grade I but still had incontinence and paralysis of his right leg.

A healthy 6-year-old girl felt weakness in both legs after performing back bend movement and fell off. She could get up again and had no pain. She had no signs or symptoms of tethered cord syndrome prior to the trauma. About 6 h later, she complained of numbness and weakness in the lower extremities and had incontinence. On admission to the hospital 3 days after injury, the patient had flaccid paraparesis, sensory disturbance below the thoracic dermatome level, and bladder and bowel dysfunction. The sagittal MRI images showed longitudinally extended diffused intramedullary patchy T1 hypointensity and T2 hyperintensity at the T6-T10 level. The conus medullary was located at L1 level. The T1 transverse-sectional MRI of sacral vertebra showed fibrolipoma of the filum terminale. The patient underwent extended surgical lysis of the filum terminale. Swelling in the conus medullary, tortuous dilation of proximal cone vessels, and 4 mm in diameter TFT with fibrolipoma were found in the operation. The fibrolipoma of the filum terminale was confirmed by histopathology (Fig. 3). Upon discharge, the patient still had paralysis of the lower extremities and incontinence. By the 8-month follow-up, the patient still had paralysis of the lower extremities and dysfunction of two bowel movements.