Functional deterioration following placode untethering in myelomeningocele

Placode untethering in myelomeningocele patients can result in improvement and/or stabilization of neurological function, spinal curvature and pain. This paper reviews the outcome of untethering procedures in 24 patients to determine the frequency of subsequent functional deterioration. Decreased range of movement, joint stiffness and changes in muscle tone were the commonest indications for surgical intervention, occurring in 15 patients. Untethering resulted in improvement in 8 patients, stabilization of progression in 6 and continued deterioration in 1 patient. Two patients previously untroubled with spasticity became symptomatic within 3 months of the procedure. Changes in ambulation were present preoperatively in 9 patients. Stabilization was observed in 4 and improvement in 5. One of the patients, who had improved, deteriorated during the 1st year of follow-up. Alterations in bladder capacity and continence occurred in 7 patients. Improvement was seen in 2 patients, deterioration in 2 and no change in 3. Of the patients who improved, 1 subsequently deteriorated again within the 2nd postoperative year. Of those patients who had stable bladder function preoperatively, 6 subsequently deteriorated despite untethering. Pain was a less frequent symptom, occurring in 6 patients. Six patients became pain-free within 3 months of untethering. Two patients who did not have pain preoperatively had pain at the operative site persisting for up to 3 months postoperatively. Of the 20 patients having a single untethering procedure to date, 11 have further symptoms that can be attributed to retethering.