Correlation of measurements of pressure perception using the pressure-specified sensory device with electrodiagnostic testing.

Abstract

Quantitative sensory testing of pressure threshold has been recommended for diagnosis and monitoring of peripheral nerve problems, yet there has been no validation of the results of such testing with electrodiagnostic testing (EDT), the "gold standard." The Pressure-Specified Sensory Device (PSSD) was used to measure the pressure threshold in 72 clinical nerve entrapment syndromes (23 carpal, 23 cubital, and 16 tarsal tunnel syndromes, and 10 common peroneal nerve entrapment at the fibular head), each of which also had EDT. There was diagnostic agreement between both EDT and PSSD in 54 of the 72 nerve entrapments (75%). The sensitivity of the PSSD was 100% for each of the four nerve entrapments. In those patients in whom there was a disagreement, the PSSD was abnormal when the EDT was normal. In conclusion, quantitative sensory testing with the PSSD has a high sensitivity, but a low specificity, when compared with EDT for diagnosis of peripheral nerve entrapment.