A surgical system kit is described. The surgical system kit includes a peripheral electrode, a surgical access instrument configured to be placed in a surgical target site, and a control unit. The surgical access instrument has a body with a proximal end, and a distal end, two or more electrodes on the distal end at fixed locations and spaced apart a known distance. The control unit is configured to send a signal to the peripheral electrode, receive information indicative of a neural response from at least one electrode of the surgical access instrument, and interpret the information according to a nerve conduction velocity modality to measure the nerve conduction velocity through the segment of the nerve.
