Children undergoing SDR for spastic cerebral palsy have significant post-operative pain. The procedure requires dissection of the lumbar back musculature and removal of the L1 lamina (the bony posterior part of the vertebra). The majority of the operation is intradural, and a water-tight dural closure at the termination of the operation is critical in order to prevent leakage of cerebrospinal fluid (CSF) from the wound. In fact, these children must remain flat on their back for 48 hours to allow the dural incision to heal prior to mobilization. Thus, adequate pain control is essential not only for patient comfort, but also to prevent agitation and additional stress on the dural closure.