Pain, according to the International Association for the Study of Pain, is “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage”.
It is the most common reason to visit a doctor and it is a major symptom in many medical conditions. It is classified according to specific characteristics, which include the region of the body, the system whose dysfunction may be causing the pain, duration and pattern of occurrence, intensity and tie since onset and the origin.
Pain is part of the body’s natural defence system and it produces a reflex retraction from the painful stimulus, and has tendencies to protect the affected body part while it heals and to avoid the harmful situation in the future. It is an important part of life and vital to healthy survival.
Types of Pain
Chronic – the main difference between acute and chronic pain is relied up on the interval of time from onset and the two most commonly used markers being up to 3 months and 6 months from onset. A popular definition of chronic pain involves no fixed duration and that it’s pain that extends beyond the expected period of healing. Richard Melzack and Patrick Wall proposed that the gate control theory that suggests that the spinal cord contains a neurological “gate” that either blocks pain signals or allows them to continue on to the brain.
Nociceptive – is caused by stimulation of the peripheral nerve fibres that respond only to a stimulus that approaches or exceeds a harmful intensity. It is classified according to the stimulus: thermal (heat or cold), mechanical and chemical. It can also be divided into visceral (diffuse, difficult to locate and often referred pain), deep somatic (initiated by stimulation of nociceptors in ligaments, bones, blood vessels, muscle, etc) and superficial somatic pain (initiated by activation of nociceptors in the skin). It is here where pain descriptions are used. It is usually described as deep, sickening, squeezing, dull, aching, sharp, well defined or poorly localized.
Neuropathic – is caused by damage to any part of the nervous system. It is often described as burning, tingling, electrical, stabbing or pins and needles.
Phantom – is more common in amputees and it is felt in a part of the body that has been lost or from which the brain no longer receives signals from.
Psychogenic – is caused, increased or prolonged by mental, emotional or behavioural factors.
Breakthrough – comes on suddenly for short periods of time and not alleviated by normal pain management. It is most common in cancer patients and those whose pain is controlled by medication.
Incident – arises as a result of activity
Idiopathic – persists after trauma or pathology that has healed or arises without any apparent cause