Pressure pain thresholds in different tissues in one body region. The influence of skin sensitivity in pressure algometry.

This study aimed at determining whether there are differences in pressure pain sensitivity in different tissues in the same body region when systematically assessed, before and after skin hypoesthesia. Pressure pain thresholds (PPTs) were assessed bilaterally in 15 healthy females at the bony part of the epicondylus lateralis humeri, at the belly of m. extensor carpi ulnaris and at m. brachioradialis where the superficial radial nerve branches pass underneath ("muscle/nerve" site). Following a double blind design, a local anaesthetic cream (EMLA) or a control cream was applied to the skin and PPTs were reassessed. The PPT was significantly (p < 0.001) lower at the "muscle/nerve" site than at the bony and "pure" muscle sites. The PPTs over the bony and "pure" muscle sites did not differ. There was no significant difference when PPTs were compared before and after application of EMLA cream. However, PPTs after control cream were lower (p < 0.001) over all examined areas than those obtained prior to cream application. Thus, EMLA cream increased PPTs compared to control sites in all examined areas (p < 0.001). Under the given circumstances, skin pressure pain sensitivity was demonstrated to influence the PPT.