Tethered cord syndrome in low motor level children with myelomeningocele.

The clinical presentation of tethered spinal cord and the results of tethered cord release were examined in a group of 30 low motor level (L3 and below) children with a history of myelomeningocele without concomitant CNS complications. Changes in orthopedic and/or neurologic status formed the basis of consideration for tethered cord release. Clinically, these patients presented with a new onset or recently progressing scoliosis, spasticity with or without contractures, decrease in motor function and low back pain at the site of closure. One or more of these findings was present in all cases and led to the suspicion of tethered spinal cord. The diagnosis of tethered cord was confirmed in all cases by MRI or CT myeolography. In order to isolate tethering as the etiology for the patients' clinical deterioration, patients with concomitant CNS complications, e.g. shunt dysfunction or hydromyelia were excluded from the study. Twenty-nine such patients, of an initial 59, who would have otherwise been considered, were excluded on the basis of this criteria of concomitant CNS complications. The results of release 1 year after the procedure were as follows: regarding scoliosis, in 75% of cases the curve either remained stable or decreased by more than 10 degrees, with 25% experiencing curve progression of > 10 degrees. The most recent follow-up in this group revealed that 11.8% experienced a decrease in curvature of >10 degrees; 47.1% remained stable, and 41.2% ultimately progressed 10 degrees. In the group with spasticity, 43.8% improved; 56.3% remained stable, and none worsened. Most (78.6%) of the children who had experienced a decline in motor function improved postoperatively, and all those with back pain experienced complete resolution. In conclusion, tethered cord release in symptomatic low lumbar and sacral level children with myelomeningocele appears to be of benefit, especially with respect to stabilization of scoliosis in selected patients, back pain at the site of closure, and prior decline in motor function. Results in the cases with spasticity were more equivocal.