ABSTRACT
INTRODUCTION: DEFINITION, PREVALENCE, AND COSTS OF CHRONIC PAIN The International Association for the Study of Pain (IASP) defines pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage” (1). Pain is the most common health-related complaint in the United States, accounting for over 80% of all doctor office visits (2). While acute pain serves a critical biologic survival mechanism, signaling injury, pain can develop from an acute, beneficial sensory phenomenon to a pathological, intractable condition. More than half of U.S. adults report experiencing some form of chronic pain during the past year and 50% of these individuals report pain lasting longer than one year (2). Chronic pain accounts for over $70 billion annually in health care costs and lost workplace productivity (2).
