Pathophysiology and Mechanisms of Chronic Musculoskeletal Pain

Chronic Musculoskeletal Pain is a prevalent cause of Chronic pain with a significant economic burden. Musculoskeletal pain can be caused by repetitive strain, overuse, work-related musculoskeletal disorders, or disease conditions. It has a variety of causes which involves any condition that affects the muscles, bone, joints, connective tissue and systemic diseases with musculoskeletal manifestations. Pain becomes chronic when it lasts for longer than 3 months and lasts more than the anticipated usual course of an acute disease or injury. The pathophysiology of chronic pain involves a combination of peripheral, central and psychologic mechanisms. It is a complex disease process that has neurologic, psychological and physiologic components. The mechanisms and modulation of pain involves a complicated process involving peripheral nociceptors, spinal cord, central nervous system, ascending and descending pain pathways, pain producing chemical agents, neurotransmitters, immune cells, and sympathetic nervous system. A complicated interaction of sensory, motivational and cognitive processes determines the complex expression of pain behavior. There are psychosocial, cultural and environmental factors involved in addition to biology that affect the complex pain experience. This Biopsychosocial model of pain experience is important in designing effective chronic pain programs and including an interdisciplinary model in the evaluation and treatment of chronic pain.