What is Selective Dorsal Rhizotomy (SDR)?
SDR involves sectioning (cutting) of some of the dorsal sensory nerve fibers that come from the muscles and enter the spinal cord. At the time of the operation, the neurosurgeon divides each of the dorsal roots into 3-5 rootlets and stimulates each rootlet electrically. By examining electromyographic (EMG) responses from muscles in the lower extremities, the surgical team identifies the rootlets that cause spasticity. The abnormal rootlets are selectively cut, leaving the normal rootlets intact. This reduces messages from the muscle, resulting in a better balance of activities of nerve cells in the spinal cord, and thus reduces spasticity. At present, SDR is the only surgical procedure that can provide permanent reduction of spasticity in CP. SDR results in improvements in sitting, standing, walking, and balance control in walking.