Chronic pain is a debatable topic, and there are uncertainties regarding its diagnosis and treatment as a clinical condition (e.g., CRPS, fibromyalgia). However past few decades, tremendous progress have been made to understand the peripheral and central processes intricate in chronic pain conditions.
The standard definition of chronic pain endorsed by the International Association for the Study of Pain states that it is pain that persists past the healing phase following an injury (Merskey and Bogduk, 1994). The medical literature defines chronic pain as pain that has lasted for more than three months.
Types of chronic pain
There is a long list of chronic clinical pain conditions. These are generally labelled by their site of injury (e.g., back, head, neck, viscera) and type of injury (e.g., neuropathic, arthritic, cancer, myofascial, diabetic).
Among these the most common one is chronic back pain.
Neuroscience of chronic pain: Most chronic pain conditions produce changes in the brain that contribute to what can be termed the “centralization of pain.” This implies that ongoing pain produces progressive alterations in brain connections, molecular biology, chemistry, and structure, with behavioural consequences. The brain region consistently affected in chronic pain conditions is the dorsolateral prefrontal lobe. which involved in several higher-order functions, including cognition, motor planning, and working memory. This centralization of pain involves alterations in sensory, emotional, and modulatory circuits, which normally inhibit pain. Thus, chronic pain may alter cognition and emotion, leading to increased fear, anxiety, or depression.
The Psychosocial factors of chronic pain: A long series of studies now describe psychosocial and psychological factors in predicting functional and social disability, where the interrelationship between ratings of catastrophizing, pain-related fear of (re-) injury, depression, disability, and pain severity is studied and modelled in combination with demographics in various chronic pain conditions. Depression is ranked as one of the strongest predictors for low back pain.
Management of Chronic Pain
Medical Management:
The clinical manifestations of chronic pain are often a combination of multiple pain conditions; even in a single condition several diverse tissue types are observed to contribute. So, it is difficult for a clinician to locate the main cause and treat patient. Recent studies shows that early mobilization and the early use of effective analgesic agents (Hagen et al., 2005) can prevent from turning into a chronic condition. However, for chronic conditions, multi-disciplinary techniques utilizing non-pharmacologic, pharmacologic and anaesthesiologic interventions are variably beneficial.
Psychological intervention:
Relaxation and Imagery Training : It has been employed in both acute and chronic pain and has been successfully implemented in the treatment of tension headache, migraine headache, temporomandibular joint pain, chronic back pain, and myofascial pain syndrome. Progressive muscle relaxation (PMR) is the most common approach used. Imagery involves talking the patient through vivid images that are particularly comforting and relaxing
Hypnosis : It is a self-induced state brought on by the patient with the assistance of the hypnotist. The mechanism of pain relief brought on by hypnosis is unclear hypnosis as a form of focused attention that is useful in managing acute and chronic pain states, including headache, fibromyalgia, back pain, trigeminal neuralgia, arthritis, phantom limb pain, and cancer pain. Analgesia produced in response to hypnosis was thought to be brought on by modification of attention control systems (i.e., anterior frontal cortex) within the brain.
Psychotherapies : Cognitive behavioral therapy, psychodynamic Psychotherapy, supporting therapy and other relevant therapies are useful in treating the chronic pain as well as the secondary effect of it, depression, anxiety and fear.
