OBJECT: Patients who have undergone myelomeningocele or lipomyelomeningocele repair may present with symptomatic retethering of the spinal cord. The authors describe the results as well as the utility of urological testing in pediatric patients undergoing multiple repeat untethering operations. METHODS: The authors reviewed the records of 13 patients with lipomyelomeningocele or myelomeningocele who underwent at least 2 untethering procedures after their initial repair and who had urodynamic testing within 6 months prior to and 6 months following each untethering operation. In each case, urological testing included a slow-fill cystometrogram and an external urethral sphincter electromyogram using a concentric needle electrode to analyze individual motor unit action potentials at rest, in response to sacral reflexes, and during bladder filling and emptying. RESULTS: New urinary symptoms were identified in 7 of 13 cases prior to surgery. Postoperative subjective improvement in urinary symptoms was noted in 5 of these 7 cases. Improvement in bladder function on urodynamic testing correlated with symptomatic improvement. Sphincter electromyography findings did not correlate with changes in preoperative symptoms or postoperative improvement. CONCLUSIONS: In patients undergoing multiple repeat spinal cord untethering operations, measuring bladder function is more useful than sphincter electromyographty when selecting candidates for surgery and for measuring surgical outcomes.
OBJECT: Patients who have undergone myelomeningocele or lipomyelomeningocele repair may present with symptomatic retethering of the spinal cord. The authors describe the results as well as the utility of urological testing in pediatric patients undergoing multiple repeat untethering operations. METHODS: The authors reviewed the records of 13 patients with lipomyelomeningocele or myelomeningocele who underwent at least 2 untethering procedures after their initial repair and who had urodynamic testing within 6 months prior to and 6 months following each untethering operation. In each case, urological testing included a slow-fill cystometrogram and an external urethral sphincter electromyogram using a concentric needle electrode to analyze individual motor unit action potentials at rest, in response to sacral reflexes, and during bladder filling and emptying. RESULTS: New urinary symptoms were identified in 7 of 13 cases prior to surgery. Postoperative subjective improvement in urinary symptoms was noted in 5 of these 7 cases. Improvement in bladder function on urodynamic testing correlated with symptomatic improvement. Sphincter electromyography findings did not correlate with changes in preoperative symptoms or postoperative improvement. CONCLUSIONS: In patients undergoing multiple repeat spinal cord untethering operations, measuring bladder function is more useful than sphincter electromyographty when selecting candidates for surgery and for measuring surgical outcomes.