Nonspecific neuronal activity elicited by intraspinal microstimulation in the intermediate and ventral gray matter of thoracic spinal segments caudal to a complete spinal cord transection significantly increased the rat hindlimb Basso,Beattie,Bresnahan locomotor score by activating the central patt generator located in the lumbar spinal cord.However,the best region for intraspinal microstimulation is unclear.Using an incomplete spinal cord injury model at T8,we compared the use of intraspinal microstimulation to activate the spinal cord in rats with a spontaneous recovery group.The intraspinal microstimulation group recovered sooner and showed three kinds of movement: the left hindlimb,the left hindlimb toes,and the paraspinal muscles and tails.These had different microstimulation thresholds.There was mild hyperplasia of the astrocytes surrounding the tips of the microelectrodes and slight inflammatory reactions nearby.These results indicate that implantation of microelectrodes was relatively safe and induced minimal damage to the lumbar-sacral spinal cord.Intraspinal microstimulation in the lumbar sacral spinal cord may improve leg movements after spinal cord injury.Non-specific intraspinal microstimulation may be a novel technique for the recovery of spinal cord injuries.