Persistent postoperative pain: where are we now?

There has been considerable interest and controversy around persistent postoperative pain for several years. Most of the available data arise from studies with methodological problems (especially its definition in terms of duration, severity, and effect on quality of life and function); however, more recent investigations have begun to address these issues. Although the quoted incidence varies considerably, analysis of the most conservative data shows that there is no doubt that persistent postoperative pain is a significant clinical problem and a burden to those who suffer from it. There is a wealth of literature describing factors associated with increased likelihood of persistent postoperative pain. Although it is difficult to be precise, it is clear that psychosocial factors probably play a role in some situations and that significant preoperative pain, severe immediate postoperative pain, and nerve damage are often good predictors. There are some data indicating that the incidence and severity of persistent postoperative pain can be reduced by special perioperative interventions; however, as yet, the evidence is not compelling and consistent. A reliable prevention strategy is not yet emerging from the published literature and considerably more work is required to deliver this.