Sensory detection and pain thresholds in spinal cord injury patients with and without dysesthetic pain, and in chronic low back pain patients.

In an effort to understand the mechanisms involved in dysesthetic pain syndrome (DPS) in spinal cord injury (SCI) patients, four groups of 13 subjects each--SCI subjects with DPS, SCI subjects without pain, chronic low back pain subjects, and control subjects--were examined for sensory detection and pain thresholds at forearm, neck, and rostral trunk areas. Results indicated that the SCI pain group had significantly lower pain thresholds at all skin sites, compared to the SCI no-pain and chronic low back pain groups, and at the rostral trunk skin site, compared to the control group. The SCI pain group also showed a lower sensory detection threshold at the rostral trunk skin site than did the SCI no-pain group. Equally important, the SCI no-pain group had detection and pain thresholds significantly higher than those of the control group. The results suggest fundamental differences in somatosensory processing when DPS is or is not a consequence of SCI.