Decoding chronic pain: insights into the transition from acute to persistent pain

Chronic pain-the persistence of pain-delineates a huge challenge to the healthcare system. During the process of pain chronification, when acute pain transitions into chronic pain, processing and pathways associated with nociceptive impulse progressively undergo diverse anatomical and physiological alterations in a process known as sensitization. Pain sensitization, which occurs in both the peripheral and central nervous system, entails intricate neurobiological mechanisms that can lead to a cascade of effects, including reduced pain threshold, augmented excitability of pain pathways and heightened sensitivity to painful stimuli. Due to the complex interplay of these neurobiological mechanisms, optimal treatment for chronic pain remains elusive. Elucidating these mechanisms further is essential to devise targeted interventions for preventing or managing chronic pain, particularly following surgical procedures. This review explores the key neurobiological mechanisms involved in the transmission of nociceptive signalling, an in-depth mechanism contributing to pain chronification, with a special focus on peripheral and central sensitization, neuroimmune interactions and neuroplastic changes within the central nervous system. It also encompasses a comprehensive overview of various therapeutic interventions, which is crucial for enhancing therapeutic strategies and patient outcomes in chronic pain management.