The idiopathic musculoskeletal pain syndromes in childhood

Pain is a ubiquitous experience and musculoskeletal pain in children is com-mon [1]. Acute musculoskeletal pain is frequent and the cause of the pain is usually obvious. Chronic pain often proves to be a difficult diagnostic and therapeutic challenge and, by definition, there are no obvious or overt noxious stimuli in children with idiopathic musculoskeletal pain to explain the pain. Because pain is subjective [2], the pain exists, it is real to the children, and it and can cause much suffering and disability to the individual and the family, often resulting in multiple visits to many different health care providers in search of diagnosis and treatment. Thus the role of the rheumatologist is a critical one, initially ruling out the multitude of mechanical, inflammatory, neoplastic, and genetic conditions that can cause chronic pain, then—once a diagnosis of idio-pathic pain is established—initiating treatment, including working with the child and family to understand and cope effectively with pain. Pain pathophysiology Acute pain in response to a noxious stimulus arises from nociceptors com-prised of either the thinly myelinated Ad fibers or by slow-conducting, non-myelinated C fibers [3]. The former are responsible for well localized, immediate pain and the later more poorly localized, burning pain. These transmit their signal by way of neuropeptides including substance P and calcitonin gene-related peptide within several spinal segments in the spinal cord. Here the signals ascen