Evaluation of pericranial myofascial nociception by pressure algometry. Reproducibility and factors of variation.

Abstract

Pressure pain detection threshold and pressure pain tolerance threshold were measured in the temples and on the fingers in 40 healthy volunteers, equally distributed as to sex and handedness. Lower pressure pain thresholds were found over the temporal muscle than in a neighbouring temporal location without interposed myofascial tissue (p less than 0.001), indicating that nociception from myofascial tissue contributes to the pressure pain threshold. Pressure pain tolerance was more reproducible within the individual subject but differed more between subjects than pressure pain detection. Pressure pain thresholds were higher on the fingers than in the temples (p less than 10(-5)) and, in general, thresholds were higher in males than in females (p = 0.02-0.09). Finally, pressure pain thresholds were lateralized in dextrals but not in sinistrals. The information that can be obtained from pressure pain detection and tolerance thresholds is discussed and examination of both threshold types is recommended in future studies.