Effect of dorsal column stimulation on pain-induced intracerebral impulse patterns.

Evoked electrical potentials were recorded via intracerebral electrodes in a patient with stump and phantom limb pain who had a previously implanted dorsal column stimulator. When pain was elicited by peripheral stimulation it was found that positive deflections appeared in the ventrolateral nucleus of the thalamus at time latencies corresponding to the propagation velocities of A delta- and C-fibres. Dorsal column stimulation completely eliminated the C-fibres. Dorsal column stimulation completely eliminated the C-fibre deflection and partially eliminated the A delta-fibre deflection.