Current Section Author: Mark A. Lumley (Wayne State University)
Original Section Author 2008-2009: David A. Williams (University of Michigan)
There are many forms of chronic pain and many ways to classify or subtype it. Chronic pain may be classified according to an underlying disease process (e.g., cancer pain, rheumatoid arthritis), a region of the body (e.g., low back pain, headaches, neck pain), a specific bodily system or medical specialty (e.g., gastrointestinal pain, urogenital pain, musculoskeletal pain, rheumatologic pain), a presumed environmental cause (e.g., whiplash-related pain, repetitive movement pain), and even a period of life (e.g., pediatric pain). Furthermore, patients evaluated and treated in practice settings, such as pain clinics, typically have a wide range of pain types and causes. Some studies of treatments of chronic pain focus on only a specific subtype, and other studies include patients with a wide range of pain types. This makes matching research-supported treatments to specific types of pain rather complicated.
Whereas acute pain acts as a warning signal of actual or imminent damage to the body, chronic pain appears to have no inherent value for survival and is best thought of as a disorder. Interventions for acute pain often fail for chronic pain, which suggests that there are different underlying pathophysiologic mechanisms and the need for distinct approaches to treatment. Pain perception is an integration of nociceptive (neural sensory system), emotional, and cognitive evaluation. Any aspect of this integrated experience can become aberrant and contribute to the maintenance and/or exacerbation of pain. Interventions for acute pain tend to target the nociceptive system; successful interventions for chronic pain tend to be those that address affective, cognitive, and behavioral factors as well. Although some psychological interventions may be effectively applied to all types of chronic pain, other psychological interventions may have greater effectiveness if targeted towards specific pain types or specific aspects of chronic pain conditions.