Is the location of nondermatomal sensory abnormalities (NDSAs) related to pain location?
OBJECTIVE
Nondermatomal sensory abnormalities (NDSAs) are alleged to be nonorganic physical findings, where one finds diminished sensation to light touch, pinprick, and, sometimes, other modalities fitting a "nondermatomal pattern." The presence of NDSAs has historically been classified as a conversion symptom. We wished to determine if, in chronic pain patients (CPPs), NDSA location was associated with pain location.


METHODS
The setting was a multidisciplinary pain facility. Patients included in the study were those CPPs who, on physical examination by two independent examiners, were found to have NDSAs. NDSA location and pain location were recorded for each CPP. Chi-square analyses (Fisher exact tests) and Kappa statistics were used to test for a relationship between NDSA location and pain location in three patient groups: Pain, upper body only; pain, lower body only; and pain, both lower and upper body.


RESULTS
Of 283 consecutive CPPs, 74 were found to have NDSAs, by both examiners, and to fulfill the inclusion criteria of this study. The relationship between NDSA location and pain location was found to be significant (Fisher exact test) for all three patient subsets: Upper body P < 0.05, lower body P < 0.0001, and upper and lower body P < 0.000001. Similarly, the relationship between NDSA location and pain location was found to be statistically significant for all three patient subsets using the Kappa statistic.


CONCLUSIONS
The findings of this study suggest that NDSA location is associated with perceived pain location. This finding has implications for whether the presence of NDSAs is considered a conversion symptom.
Fishbain
David A
DA
Department of Psychiatry, University of Miami School of Medicine, Miami, Florida, USA. d.fishbain@miami.edu
Cutler
R B
RB
Lewis
John
J
Cole
Brandly
B
Rosomoff
R Steele
RS
Rosomoff
H L
HL
D000328:Adult; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000150:complications / Q000503:physiopathology* / Q000523:psychology*; D020886:Somatosensory Disorders / Q000209:etiology / Q000503:physiopathology* / Q000523:psychology*; D014110:Touch