Acute to chronic pain transition in extremity trauma: A narrative review for future preventive interventions (part 1)

BackgroundSeveral studies have been conducted over the last decade that describe the issue of pain and prognostic factors of acute to chronic pain transition post extremity trauma (ET). However, no thorough interventions to prevent chronic pain development in ET patients have yet been proposed.ObjectivesThis first part of a series of two articles aimed to provide a comprehensive analysis of literature on the epidemiology of pain post-ET, the impact of persistent pain on ET patients and the relevant biological transformations involved in acute to chronic pain transition. The second article will focus on risk and protective factors relating to chronic pain that could potentially assist in the development of preventive interventions.MethodsA narrative review of the literature was undertaken. Databases were searched to identify relevant studies and seminal works on the topics of interest.ResultsThe review revealed that acute pain converts to chronic pain in up to 86% of ET patients. Analysis of study findings also indicated that chronic pain interferes with activities of daily living and capacity to work. Weak associations between chronic pain and anxiety as well as depression have been demonstrated. Anxiety and depression have been identified as important predictors of chronic pain post-ET. Neuro-immunological transformations, genetics and an emotional shift in the brain circuitry involved in nociception have been shown to contribute to the transition towards chronic pain.ConclusionsThis narrative review supports the view that acute to chronic pain transition is a prevalent and significant issue post-ET. It also provides information about patients who present a higher risk of chronic pain and features that should be integrated in preventive interventions as well as methodological considerations pertaining to the evaluation of such interventions.