Neurologic testing with somatosensory evoked potentials in idiopathic scoliosis.

A study was undertaken to determine if a somatosensory conduction delay is present in the posterior columns of adolescents with idiopathic scoliosis. Somatosensory evoked potentials were recorded after median and posterior tibial nerve stimulation in 12 adolescent subjects being followed for idiopathic scoliosis with an average age of 14.6 years (range, 12.0-16.6 years). Twelve normal controls matched for age, sex, race, and height underwent identical testing. Evoked potential peak latencies were measured and conduction velocities calculated. Results showed no difference between scoliotics and normal controls. Comparable posterior column conduction velocities were recorded in both groups. If a defect in posterior column function does exist in adolescent idiopathic scoliosis, as previously postulated, it is not reflected by a conduction delay as measured by somatosensory evoked potential testing.