Group leader and participants Chronic Pain -Dr. Daniel Clauw Associate Dean for Clinical and Translational Research and Director, Chronic Pain and Fatigue Research Center, Univ. of Michigan -Dr. William Maixner Director, Center for Neurosensory Disorders, Univ. of North Carolina at Chapel Hill -Dr. Clifford Woolf Director, Neural Plasticity Research Group and Richard Kitz Chair of Anesthesia Research, Massachusetts General Hospital and Harvard Univ. -Dr. Jim Witter Program Director, Division of Skin and Rheumatic Diseases, NIAMS -Dr. Jonelle Drugan Science Policy Analyst, Office of Science Policy and Planning, NIAMS -Dr. Cheryl Lapham Program Director, Division of Skin and Rheumatic Diseases, NIAMS -Dr. Gayle Lester Program Director, Division of Musculoskeletal Diseases, NIAMS -Dr. John Kusiak Director, Molecular and Cellular Neuroscience Program, National Institute of Dental and Craniofacial Research 2008 NIAMS Scientific Retreat

Overarching question -How can the NIAMS contribute toward understanding chronic pain and developing treatment options for patients who suffer from chronic musculoskeletal pain? Key Discussion Points -Types of pain -Neuroplasticity and pain -Heterogeneity of pain syndromes Chronic Pain 2008 NIAMS Scientific Retreat

All Pain is not the Same Four types of pain -Nociceptive, protective pain—generated by the presence of tissue-damaging stimuli and responds to NSAIDs and opioids -Neuropathic pain—caused by damage or entrapment of peripheral nerves and responds to neuroactive compounds (such as tricyclic antidepressants) and traditional analgesics -Inflammatory pain—caused by tissue injury -Dysfunctional, non-nociceptive (central) pain—occurs without obvious signs of tissue damage Inflammatory pain and non-nociceptive pain are associated with -Allodynia—the perception of pain in response to a benign stimulus -Hyperalgesia—heightened sensitivity to noxious stimuli 2008 NIAMS Scientific Retreat

Points of Consideration Interactions among the peripheral and central nervous systems and the inflammatory system -Patients with chronic pain conditions undergo neurobiological, psychological, and cognitive and behavioral changes that dramatically affect symptoms and functioning Reversible and permanent biochemical and anatomic changes that cause or are caused by chronic pain -Mechanisms underlying allodynia and hyperalgesia -Transition from pain as a symptom of a disease to a chronic condition that can be prevented, treated, or cured The heterogeneity of pain syndromes -Genetic risk factors -Mechanisms by which chronic pain develops -Variations in phenotypic manifestations 2008 NIAMS Scientific Retreat