A tethered spinal cord results from tissue attachments in the spinal canal that cause abnormal spinal cord stretching. Release surgery seeks to sever those attachments to avoid or reverse neurological impairment. Several factors affect the likelihood of complications, and the most significant of these is the patient's age. Younger children have the best prospects for relief of symptoms. The number and extent of adhesions in the spinal cord, as well as the patent's general health, also are important.
Genitourinary and Sexual Complications
The most serious complication of tethered spinal cord surgery is a condition called atonic bladder, according to a 2007 article in "Neurosurgical Focus." Another 2007 article in the same journal states that this dysfunction occurs in about 2 percent of cases. The problem occurs when the bladder's muscle tone is lost because of injury to the spinal roots that control the bladder. This complication can be minimized by partly untethering the spinal cord instead of fully untethering it.
Electronic monitoring techniques have been used to help identify spinal roots or neural tissue, particularly if they are at risk of injury because they're obscured by scars or other structures. Unfortunately, these techniques have not proven to minimize the rate of atonic bladder complications.
Another related complication of the surgery is sexual and bowel dysfunction. These complications can be either permanent or transient.
Cerebrospinal Fluid Leakage
Cerebrospinal fluid leakage is another possible complication of surgery to untether the spinal cord and can occur up to 31 percent of the time, according to a 2007 article by J. Blount in "Neurosurgical Focus." Cerebrospinal fluid is the liquid that bathes the spinal cord and spinal nerve roots and is contained by a membranous sac, called the dura mater, surrounding these tissues. The fluid serves as a vehicle for nutrients as well as mechanical protection for the spinal cord and spinal nerve roots.
As the "Journal of Neurosurgery" notes, the dura mater tends to thin out when untethering occurs and adhesions are removed. It often requires patching with the patient's own tissues or artificial tissue to close or strengthen the defect. If the defect is improperly sealed, the cerebrospinal fluid can leak out. This can lead to the erosion and permanent injury of the neural tissues beneath. The result may be neurological dysfunction.
Revision Surgery
The "Journal of Neurosurgery" reports that one serious complication of surgery to untether the spinal cord is retethering, which requires another surgery. It occurs because the original surgery may have caused scarring and pinning of the spinal cord by fibrous tissues. These tissues thicken and eventually create fresh tethers, which ultimately result in the return of pain. Repeated surgery is necessary more often in children than in adults--about 57 percent of children need it, but only about 16 percent of adults do.
References
- "Neurosurgical Focus"; Surgical Management of the Tethered Spinal Cord; J. Drake; August 2007
- Long Island Neurological Association: Laminectomy for Tethered Cord
- "Neurosurgical Focus": Spinal Cord Transection for Definitive Untethering
- "Neurosurgical Focus"; Spinal Lipomas; M. Finn and M. Walker; August 2007
- "Journal of Neurosurgery"; Surgical Management of Tethered Cord Syndrome in Adults; G. Lee et. al.; February 2006
