The role of motor evoked potentials in the management of a case of presumed hysterical paraplegia precipitated by spinal injury in a man with a previous history of surgery for scoliosis is presented. Motor evoked potentials were elicited with magnetic stimulation 12 days after injury and were within normal limits. The presence of normal motor electrophysiology and observation by the patient of involuntary movement of the lower limbs during stimulation greatly facilitated the patient's management. These findings are discussed with reference to current diagnostic investigations in the presence of a suspected diagnosis of hysterical paraplegia.