Neurophysiologic intraoperative monitoring during selective dorsal rhizotomy

Selective dorsal rootlet rhizotomy (SDR) is a neurosurgical procedure designed to reduce spasticity in the legs, although preserving motor and sensory function, of appropriately selected children with spastic quadraparesis. This is accomplished by neurophysiologicially guided (e.g., selective) severing of specific dorsal rootlets in the cauda equina. This decreases facilitatory input to spinal anterior motor neurons, thereby reducing spasticity in the legs. This first portion of this article discusses the neurophysiologic intraoperative monitoring techniques during SDR, with the understanding that there are no universally agreed upon protocols nor standards of care. The second portion of the article reviews supporting data for the utility of SDR and long-term outcomes. With major benefits attributed to the selective nature of the procedure, SDR was increasingly used in the 1980-1990's after its introduction by Fasano et al. (Neurochirurgie. 1976;22:23-34; Acta Neurochir. 1977;suppl 24:53-57; Child's Brain. 1978;4:289-305) and revision by Peacock and colleagues (S Afr Med J. 1981;60:849-850;S Afr Med J. 1982;62:119-124). More extensive SDR discussions of its history, theoretical and physiological bases, patient selection criteria, neurosurgical techniques, and postoperative and long-term management, may be found elsewhere.