Recent onset vs. persistent pain: evidence for a distinction.

Evidence for a distinction between chronic and recent onset pain on behavioural and subjective indices was reviewed. Pain behaviours and subjective indices of pain were studied in chronic and recent onset low back pain sufferers. No differences were found between chronic and acute sufferers on measures of pain behaviour, nor on subjective indices of pain. However, differences were found in the relationships between the subjective and behavioural indices of pain in these groups. Pain behaviours were found to be independent of the subjective pain experience in recent onset pain. The relationships between subjective pain experience and pain behaviour became stronger with increased pain duration. The relationships between behavioural dimensions of pain weakened with chronicity, as did the relationship between subjective pain dimensions. These findings were discussed in relation to current accounts of chronic and recent onset pain and their implications for both theory and treatment were considered.