Acute and persistent pain are very different clinical conditions. Acute pain is a result of tissue injury or inflammation, and serves the vital purpose of alerting you that there is an injury or disease in part of your body that you should attend to it. This pain is time limited, lasting minutes to a few months, and resolves when the tissue damage is healed.
Conversely, persistent pain is a disease state in which the pain outlasts normal healing times. It also serves no biologic purpose, and is often accompanied by psychological stress.
Medical approaches to acute pain are aimed at treating the underlying cause and blocking pain signals. The therapeutic approach to persistent pain is multidisciplinary, using multiple physical and psychological strategies to interrupt the pain cycle.