Split Cord Malformation Combined with Tethered Cord Syndrome in an Adult
A 34-year-old woman was admitted with neck pain, back pain, and recurrent bilateral leg weakness of 2 months duration. On physical examination, there was a paresis with 4/5 muscle strength and deep tendon hyperreflexia in both legs. There were no pathologic reflexes. The initial neurologic evaluation revealed sensory numbness below the level of the C-7 dermatome. An urodynamic study, somatosensory evoked potentials, and electromyograhic evaluation showed no abnormalities.\nThe radiologic examination revealed mild scoliosis of the thoracic spine, hemi-vertebrae at T6 level, and butterfly vertebral bodies at T11 level. Spina bifida was also present. The admission cervicothoracic MRI showed that the spinal cord was divided into two segments from the level of C-7 to T-11, and there was development the subcutaneous fat within the bifid spine. No fibrous septum was demonstrated on MR imaging. On lumbosacral MRI, the conus was shown to be low-lying, ending at the L5 level (). CT myelography showed that dye was leaked incidentally into the epidural and intradural spaces. A fibrous septum divided the spinal cord and extended to the epidural space and attached to the ventral cortex of the lamina at T9 level ().\nThe patient underwent surgery to prevent progression of the neurologic damage resulting from tethering of the spinal cord. A laminectomy was performed from the level of T-8 to T-11. The T-9 and T-10 spines were bifid and abnormal fat tissue was infiltrated between the bisected spinous process. Surgery revealed a symmetric duplication of the spinal cord above the level of T-10, which was encompassed by a single dural sac, and the fibrous septum was recognized between the divided hemi-cord at the T-9 level, 10 mm above the cord reunion site (T-10). The fibrous septum splits and tethers spinal cord. The tethered spinal cord was released by resection of the fibrous septum ().\nAfterwards, a L5 and S1 laminectomy was performed to release the tethered cord syndrome by the thickened filum terminale. The nerve roots appeared slightly adherent to the dura at the L-5 level, and resection of the thickened filum was made because the cord was tethered at the level of the lesion (). The patient had an uneventful postsurgical recovery.\nAt the 7-year follow-up examination, the patient had a normal neurologic examination, with no complaints of episodic paraparesis or back pain.