Tethered Spinal Cord
Tethered spinal cord syndrome refers to a group of neurological disorders that relate to malformations of the spinal cord. Various forms include:
- Tight filum terminale
- Split spinal cord malformations
- Dermal sinus tracts
Normally, the spinal cord hangs loose in the canal giving it the ability to move up and down with growth and during bending and stretching. A tethered cord, however, is held tight at the end or at some point in the spinal canal, making it so the cord is not free to move. In adults the spinal cord stretches in the course of normal activity, usually leading to progressive spinal cord damage if untreated. Tethered spinal cord syndrome is often associated with the closure of aspina bifida. It can be congenital, such as in tight filum terminale, or the result of injury later in life.
- Lesions, hairy patches, dimples, or fatty tumors on the lower back
- Foot and spinal deformities
- Weakness in the legs
- Change in or abnormal gait including awkwardness while running or wearing the tips or side of one shoe
- Low back pain
- Urinary irregularities (incontinence or retention)
Symptoms of a neuropathic bladder are seen in over 70 percent of adult patients, versus only 20 percent to 30 percent of children. These symptoms include urinary frequency and urgency, feeling of incomplete voiding, poor voluntary control, and urge and stress incontinence. Chronic recurrent infections are common and occasionally lead to nephrolithiasis (kidney stones), renal failure, or renal transplantation.
Tethered spinal cord syndrome may go undiagnosed until adulthood, when sensory, motor, bowel, and bladder control issues emerge. This delayed presentation of symptoms relates to the degree of strain on the spinal cord over time.
Tethering may also develop after spinal cord injury. Scar tissue can block the flow of fluids around the spinal cord. Fluid pressure may cause cysts to form in the spinal cord, a condition called syringomyelia. This can lead to additional loss of movement or feeling, or the onset of pain or autonomic nervous system symptoms.
Operations to release a tethered spinal cord have been developed by pediatric neurosurgeons and may be recommended in cases in which there are clinical signs or symptoms of deterioration. Because tethered cord syndrome can occur due to a person's genetic makeup, the exact techniques used to perform such operations vary depending upon the complexity of the underlying cause. These operations commonly involve microsurgical technique and sometimes employ laser surgical technique often with intraoperative physiologic monitoring of neurological function during the procedure.