Pain

An unpleasant sensory and emotional experience associated with or resembling that associated with actual or potential tissue damage

The normal predicted physiological response to an adverse chemical, thermal or mechanical stimulus

Long standing pain that persists beyond the usual recovery period or occurs along with a health condition such as arthritis

A type of pain caused by damage to body tissue it feels like sharp, aching or throbbing often caused by an external injury

A term used to describe persistent pain that arises from altered nociception despite no clear evidence of actual or threatened tissue damage

Occurs when a health condition affects the nerves that carry sensations to your brain

Damaging or threatens damage to normal tissues potentially causing pain it exceeds a certain threshold to activate nociceptors

The process of painful stimuli being transformed into a signal that can be carried to the central nervous system

The relay functions by which the message is carried from the site of injury to the brain regions underlying perception

Perception of pain occurs when stimulation of nociceptors is intense enough to activate if its not we wont feel pain

Process by which the body alters a pain signal as it is transmitted along the pain pathway, it explains why individuals response to the same painful stimulus differs

The sensory nervous systems process of encoding noxious stimuli

Specialised sensory nerve ending that can detect noxious stimuli usually associated with tissue damage or potential injury

Pain response to a normally non painful stimulus

Found in areas of tissue damage

Evident in skin adjacent or distant to the area of damage

Mechanociceptors - respond only to intense mechanical stimulation such as pinching Thermalnociceptors - respond to the above stimuli as well as thermal stimuli

Mechanical, chemical or thermal

Biological - age, existing medical conditions, medications and genetics Sociological - cultural beliefs, social support, where injury took place and activities of daily living Psychological - stress, coping mechanisms, beliefs about pain, mood and expectations

Increased excitability - repeated stimulation causes release of mediators which increase resting potential causing hyperalgesia Stimulation of silent neurons - inflammatory mediators causes the stimulation this causes allodynia Up regulation of gates - sodium ion channel gates are held open, more gates are produced

Wind up - progressive amplification of pain signals in response to stimuli leading to increased perception of pain over time Opening NMDA channels - facilitates increased calcium influx contributing to synaptic potential and heightened responsiveness to pain stimuli Neuroinflammation - release of inflammatory bio markers sensitise nociceptive pathways amplifying pain signals Dysregulated pain modulation and neurotransmitter release - imbalance between excitatory and inhibitory signalling leading to enhanced pain perception

Hyperalgesia - increased axonal sensitivity to mechanical, thermal and chemical stimuli Allodynia - the occurrence of pain in response to stimuli that are not typically painful Spontaneous pain - neuropathic pain can involve spontaneous pain sensations including burning, tingling or shooting which may occur without a trigger Altered synaptic transmission and central sprouting - refers to abnormal communication between nerve cells and the abnormal growth of nerve fibres contributing to dysfunctional signalling in nervous system and amplification of pain perception