Electrophysiological phenotyping of neuropathic pain following spinal cord injury

Pain-related evoked potentials provide an objective assessment of nociceptive pathways. The application of multimodal electrophysiological recordings is of high value to assess the integrity of nociceptive pathways while lesions of spinothalamic projections are considered indispensable for the development of neuropathic pain following spinal cord injury. Depending on the type of stimulation, i.e., laser, heat, mechanical, or electrical, specific primary afferents and projections of the spinothalamic tract can be discerned. The dermatomal stimulation across defined spinal segments, e.g., segments adjacent to focal lesions within the cervical and thoracic cord, enables topographical diagnostics within the spinothalamic pathways. The high specificity and sensitivity of spinothalamic assessments complements clinical assessments in the evaluation of neuropathic pain following a spinal damage. Beyond the diagnostic value of revealing damage to nociceptive pathways, evoked potentials can be utilized to assess alterations in central pain processing. Impaired habituation of pain-related evoked potentials and pathological pain-autonomic interaction may resemble electrophysiological correlates of the clinical pain phenotype.