AbstractMusculoskeletal pain (MSKP) was proposed to arise from various mechanisms out of which nociceptive mechanism was common. Role of Sympathetic nervous system (SNS) in MSKP was not recognized until stress was found to have effect on MSKP. Thus this review focuses on the role of SNS in MSKP and itsevaluation and treatment.Recent studies have suggested that SNS contributes to chronic pain. It forms the secondary component of pain dysfunction. This type of pain was termed as ‘Sympathetically Maintained Pain’ (SMP). It can occur due to a pathophysiological or pathomechanical cause. Various mechanisms have been proposed for SMP based on animal and human studies. It has been proposed that sympathetic- sensory coupling is responsible for SMP. Sympathetic- sensory coupling can occur directly in dorsal root ganglia, chemical coupling in the skin, or development of alpha adrenoceptor mediated supersensitivity. The mediator for the coupling is nor-adrenalin and the adrenergic receptors involved are the alpha 2 adrenoceptors.Diagnosis of SMP is based on signs and symptoms, routine physical examination, specific neurodynamic tests like Sympathetic Slump test, and sympathetic blockade. SMP is managed using pharmalogical treatment and physical therapy. Thus, SMP presents as a true clinical challenge and key to successful management is early diagnosis and treatment.
Keywords: Sympathetically maintained pain; Chronic pain; Sympathetic nervous system; Musculoskeletal pain; Sympathetic slump.