Management of adult tethered cord syndrome

ABSTRACT

This study was done to evaluate the surgical outcome of untethering of the cord in a consecutivec 10 adult patients suffering from tethered cord syndrome. This prospective study was carried out on consecutive 10 adult patients suffering from manifestations due to tethering of the cord. The patients were admitted to the Alexandria main university hospital over a period of 3 years starting from March 2002 to March 2005. The male to female ratio was 7 to 3 and their ages ranged from 25 till 57 years with mean age of 38.5. Most patients [9 patients] suffered from low back pain, while 7 patients showed signs of root affection and radiculopathy, sphincteric disturbances were present in all patients. Interestingly one patient had bilateral neuropathic ulcers at the site of the heel. All our patients developed signs and symptoms of tethered cord syndrome in adulthood. All patients were subjected to preoperative MRI of the lumbosacral spine, urodynamic study, and preoperative electrophysiological study of the lumbo-sacral plexuses. Intraoperative electrophysiological monitoring maneuvers using a bipolar stimulating electrode were used to identify functional neural tissue from the filum terminale and the response of lower limb muscles, and external anal sphincter were recorded either manually or by electromyography. Untethering of the cord using surgical microscope was done under general anesthesia without muscle relaxation. Dural graft was used in one case with secondary adhesions. Mean postoperative follow-up period was 15 months, including both clinical and MRI examination. The lower level of the conus was at lumbar vertebra L2 in one case, at L4 in 6 cases and at level from L5 to sacrum in 3 cases. The tethering lesions were tight filum terminale in 7 patients, lipoma in 2 patients, and secondary adhesions in one patient. Thickness of the filum was ranged from 1 to 7mm with a mean of 3.7mm. There was no operative mortality, and surgery did not provoke any permanent neurological aggravation of our cases. After surgery 2 patients [20%] were asymptomatic, 5 patients [50%] improved, and 3 patients [30%] stabilized, also all the patients were independent. The surgical outcome after tethered cord release in the adults is favorable, as most patients report improvement or stabilization of their symptoms. Safe surgical treatment with minimal complications and side effects can be achieved with the aid of intraoperative neurophysiological monitoring techniques. The success of surgery depends on early diagnosis and complete untethering of the spinal cord. It seems reasonable to recommend early surgical treatment in both symptomatic and asymptomatic adults