pain threshold (redirected from pain thresholds)

pain threshold,

the point at which a stimulus, usually one associated with pressure or temperature, activates pain receptors and produces a sensation of pain. Individuals with low pain thresholds experience pain much sooner and faster than those with higher thresholds; individuals' reactions to stimulation of pain receptors vary.

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pain,

n an unpleasant sensation created by a noxious stimulus mediated along specific nerve pathways to the central nervous system, where it is interpreted. The sensation of pain is a protective mechanism that warns of danger without giving too much information about the specific nature of the danger. It initiates nociceptive reflexes.

pain and suffering,

n an element in a claim for damages in a liability lawsuit. It requests compensation to an individual for mental and physical pain and discomfort as a result of an injury.

pain, assessment,

n an evaluation of the reported pain and the factors that alleviate or exacerbate a patient's pain; used as an aid in the diagnosis and the treatment of disease and trauma.

pain, chest,

n pain that occurs in the chest region because of disorders of the heart (e.g., angina pectoris, myocardial infarction, or pericarditis), pulmonary artery (pulmonary embolism or hypertension), lungs (pleuritis), esophagus (“heartburn”), abdominal organs (aerophagia, biliary tract disease, splenic infarction, or gaseous distention in the splenic flexure), or the chest wall (neoplasia, costochondral strains, trauma, hyperventilation, or muscular tension).

pain clinic,

n a multidisciplinary association of health care professionals devoted to the diagnosis and treatment of patients with acute and chronic pain.

pain, deep,

n dull, aching, or boring pain originating in muscles, tendons, and joints. It is poorly localized and tends to radiate.

pain dysfunction syndrome,

n in dentistry, a phrase used to describe a condition in patients who appear to have a psychophysiologic basis for stress overload on the temporomandibular joint. The preferred term is
mandibular stress syndrome.

pain, ghost,

n See odontalgia, phantom.

pain mechanism,

n the network that communicates unpleasant sensations and the perceptions of noxious stimuli throughout the body in association with both physical disease and trauma involving tissue damage.

pain, nerve ending,

n a receptor nerve ending that is relatively primitive and ends in an undifferentiated arborization. The nerve ending for the sensation of pain is a protective mechanism that warns of danger without giving too much information about the specific nature of the danger. The danger stimuli give rise to nociceptive reflexes, or defensive, protective, or withdrawal movements. The nociceptive reflexes supersede other, less urgent, reflexes that are thus inhibited.

pain, projected pathologic,

n pain erroneously perceived to arise in a peripheral region because of a stimulus from end-organs supplying the region (e.g., sciatic pain). Actually the stimulus occurred somewhere along the pain pathway from the nerve to the cortex.

pain, reaction,

n the individual's manifestation of the unpleasant sensation.

pain, referred,

n pain caused by an agent in one area but manifested in another (e.g., pain caused by caries in the maxillary third molar may be referred to the mandible, so the source of pain appears to be in the mandible).

pain stimulus,

n an agent that has the potential to induce pain, whether through chemical, mechanical, or thermal means.

pain, tactile stimuli,

n any of a number of physical sources that may aggravate dentin hypersensitivity, such as dental instruments, toothbrush bristles, ill-fitting oral prostheses, and various personal oral habits a patient may have.

pain, thermal stimuli,

n dentin hypersensitivity related to abrupt changes in temperature of teeth as a result of contact with very cold or very hot foods and liquids, rapid intake of air through the oral cavity, and during professional oral hygiene procedures requiring rapid drying of teeth.

pain threshold,

n the point at which a stimulus causes pain. It varies widely among individuals.

pain, tolerance,

n the maximum pain level an individual is able to withstand.

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pain

a feeling of distress, suffering or agony, caused by stimulation of specialized nerve endings. Its purpose is chiefly protective; it acts as a warning that tissues are being damaged and induces the sufferer to remove or withdraw from the source.

All receptors for pain stimuli are free nerve endings of groups of myelinated or unmyelinated neural fibers abundantly distributed in the superficial layers of the skin and in certain deeper tissues such as the periosteum, surfaces of the joints, arterial walls, and the falx and tentorium of the cranial cavity. The distribution of pain receptors in the gastrointestinal mucosa apparently is similar to that in the skin; thus, the mucosa is quite sensitive to irritation and other painful stimuli. Although the parenchyma of the liver and the alveoli of the lungs are almost entirely insensitive to pain, the liver as an organ and the bile ducts are extremely sensitive, as are the bronchi, ureters, parietal pleura and peritoneum.

Some pain receptors are selective in their response to stimuli, but most are sensitive to more than one of the following types of excitation: (1) mechanical stress of trauma; (2) extremes of heat and cold; and (3) chemical substances, such as histamine, potassium ions, acids, prostaglandins, bradykinin and acetylcholine.

The conscious perception of pain probably takes place in the thalamus and lower centers; interpretation of the quality of pain is probably the role of the cerebral cortex.

There are some naturally occurring internal systems in the body that are known to control pain but none of them has been completely verified. One of the best known is the gate control system in which it is thought that pain impulses are mediated in the substantia gelatinosa of the spinal cord.

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abdominal pain

pain occurring in the area between the thorax and pelvis. Manifestations vary between species. Identifiable syndromes include: (1) horse—pawing, flank watching, rolling, straddling as though to urinate, lying on the back; (2) cattle—may depress back and paddle with hindfeet but mostly arched back, grunting, immobility; (3) dogs and cats—arched back, grunting, depression, reluctance to move. Sometimes there is elevation of the hindquarters, with the chest and forelegs on the ground (the so-called 'praying dog' attitude).

Beagle pain syndrome

see beagle pain syndrome.

projected pain

pathology in one area can affect the nerve supply to a distant area in which pain is experienced.

pain receptors

free nerve endings of tufts of fine points or buttons.

referred pain

pain felt in an area distant from the site of pathology but not mediated through a common innervation. There is no evidence that referred pain occurs in animals but it seems likely on anatomical grounds.

pain threshold

the lowest level at which a stimulus can be applied and cause perceptible pain.

pain tolerance

the level of stimulation at which pain becomes intolerable.