The International Association for the Study of Pain defines pain as an unpleasant sensory and emotional experience with actual or potential tissue damage.
Acute pain is the normal, predicted physiological response to a noxious chemical, thermal or mechanical stimulus and typically is associated with invasive procedures, trauma and disease. It is generally time-limited.
Chronic pain is defined as pain that persists beyond the usual course of an acute disease or injury, usually considered to be from six weeks to 90 days. Chronic pain may or may not be associated with an acute or chronic pathologic process that causes continuous or intermittent pain over months or years.
Chronic pain is classified into three types; Nociceptive, Neuropathic and Psychogenic.
Nociceptive pain is caused by tissue damage. Somatic Nociceptive pain from musculoskeletal sources is a localized pain whereas visceral pain is non-localized, such as that from gallbladder or kidney.
Neuropathic pain is that pain caused by damage to nerves from diseases such as diabetes mellitus, herpetic neuralgia, sickle cell disease or reflex sympathetic dystrophy.
Psychogenic pain is included in the American Psychological Association diagnosis for Pain Disorder, which describes the mental, social and behavioral processes of chronic pain.
Multimodal therapy is well established in the treatment of chronic pain. Physical therapy, manipulation, soft tissue treatments; massage and stretching as well as acupuncture and other alternative care recommendations are endorsed by the author.