Introduction: Pain and its Mechanism

Abstract

Classification of pain and their mechanisms are described in this chapter. Pain is classified into three categories according to the mechanisms; these are nociceptive pain, neuropathic pain and psychological pain. Nociceptive pain is caused by tissue damage and accompanies inflammation. Neuropathic pain is defined as pain arising as a direct consequence of a lesion or disease affecting the somatosensory system. Psychological pain is pain that is particularly attributable to the thought process, emotional state, or personality of the patient in the absence of an organic or delusional cause or tension. The characteristics of these different types of pain and methods of pain assessment are also described.