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There are two types of nociceptors corresponding todierent pain sensations. Myelinated pain bers conductat speeds of 12 to 30 m/sec and produce the sensation offast (rst) paina feeling of sharp! locali"ed! stabbingpain percei#ed at the time of in$ury. %nmyelinated painbers conduct at speeds of 0.& to 2.0 m/sec and producethe slow (second) pain that followsa longer'lasting! dull!

diuse feeling. (ain from the s)in! muscles! and $oints iscalled somatic pain, while pain from the #iscera is calledvisceral pain.The latter often results from stretch! chemicalirritants! or ischemia *poor blood +ow,! and it is oftenaccompanied by nausea.590

Saladin: Anatomy &Pysiolo!y: "e #nity of$orm and $%nction, "irddition- The Mcrawillompanies! 2003

'%taneo%s and eep Somatic Pain

utaneous pain arises from supercial structures! such asthe s)in and subcutaneous tissues. paper cut on the ngeris an eample of easily locali"ed supercial! or cutaneous!pain. 4t is a sharp! bright pain with a burning 5ualityand may be abrupt or slow in onset. 4t can be locali"ed accuratelyand may be distributed along the dermatomes. 6ecausethere is an o#erlap of ner#e ber distribution betweenthe dermatomes! the boundaries of pain fre5uently are notas clearcut as the dermatomal diagrams indicate.7eep somatic pain originates in deep body structures!such as the periosteum! muscles! tendons! $oints! and blood#essels. This pain is more diuse than cutaneous pain.8arious stimuli! such as strong pressure eerted on bone!ischemia to a muscle! and tissue damage! can producedeep somatic pain. This is the type of pain a person eperiences

from a sprained an)le. 9adiation of pain from theoriginal site of in$ury can occur. :or eample! damage to aner#e root can cause a person to eperience pain radiatingalong its ber distribution.

Sin Pain and eep Sensi*ility s indicated earlier! the ner#eendings in each tissue are acti#ated by dierent mechanisms! andthe pain that results is characteri"ed by its 5uality! locale! and temporalattributes. Skin pain is of two types; a pric)ing pain! e#o)edimmediately on penetration of the s)in by a needle point! and astinging or burning pain! which follows in a second or two. Togetherthey constitute the ewis. 6oth types

of dermal pain can be locali"ed with precision. ompression ofner#e by the application of a tourni5uet to a limb abolishes pric)ingpain before burning pain. >i)e the sensation of a limb

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analgesic medication * (%6>4D4E 7484D4AE 2005,

Managing painonsidering the dierent causes and types of pain!as well as its nature and intensity! management can

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re5uire an interdisciplinary approach. The elements ofthis approach include treating the underlying cause ofpain! pharmacological and nonpharmacological therapies!and some in#asi#e *surgical, procedures.

Treating the cause of pain underpins the idea ofmanaging it. 4n$uries are repaired! diseases are diagnosed!

and certain encounters with pain can be anticipatedand treated prophylactically *by pre#ention,. owe#er!there are no guarantees of immediate relief from pain.9eco#ery can be impeded by pain and 5uality of life canbe damaged. Therefore! pharmacological and other therapiesha#e de#eloped o#er time to address these aspectsof disease and in$ury.PA/-A'123'A1 P"34S. (ain'relie#ing drugs!otherwise called anal!esics! include nonsteroidal antiinammatorydr%!s *ED47s,! acetaminopen! narcotics!antidepressants! anticon#ulsants! and others.ED47s and acetaminophen are a#ailable as o#er'thecounterand prescription medications! and are fre5uentlythe initial pharmacological treatment for pain. These drugscan also be used as ad$uncts to the other drug therapies!which might re5uire a doctorBs prescription.ED47s include aspirin! ibuprofen *Motrin! d#il!Euprin,! naproen sodium *le#e,! and )etoprofen*Arudis CT,. These drugs are used to treat pain fromin+ammation and wor) by bloc)ing production of painenhancingneurotransmitters! such as prostaglandins.cetaminophen is also eecti#e against pain! but its abilityto reduce in+ammation is limited.ED47s and acetaminophen are eecti#e for mostforms of acute *sharp! but of a short course, pain! butmoderate and se#ere pain may re5uire stronger medication.Earcotics handle intense pain eecti#ely! and areused for cancer pain and acute pain that does not respondto ED47s and acetaminophen. Earcotics are classiedas either opiates or opioids! and are a#ailable only with adoctorBs prescription. Apiatesinclude morphine andcodeine! which are deri#ed from opium! a substance naturallyfound in some poppy species. Apioids are syntheticdrugs based on the structure of opium. This drug classincludes drugs such as oycodon! metadone! andmeperidine *7emerol,.Earcotics may be ineecti#e against some forms ofchronic pain! especially since changes in the spinal cordmay alter the usual pain signaling pathways. :urthermore!narcotics are usually not recommended for longterm

use because the body de#elops a tolerance to narcotics!reducing their eecti#eness o#er time. 4n such situations!pain can be managed with antidepressants andanticon#ulsants! which are also only a#ailable with adoctorBs prescription.lthough antidepressant dr%!s were de#eloped totreat depression! it has been disco#ered that they are alsoeecti#e in combating chronic headaches! cancer pain!and pain associated with ner#e damage. ntidepressants

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that ha#e been shown to ha#e analgesic *pain reducing,properties include amitriptyline *Hla#il,! tra"odone*7esyrel,! and imipramine *Tofranil,. Anticonv%lsantdr%!s share a similar bac)ground with antidepressants.7e#eloped to treat epilepsy! anticon#ulsants were foundto relie#e pain as well. 7rugs such as phenytoin *7ilantin,

and carbama"epine *Tegretol, are prescribed to treatthe pain associated with ner#e damage.Ather prescription drugs are used to treat specictypes of pain or specic pain syndromes. :or eample!corticosteroids are #ery eecti#e against pain caused byin+ammation and swelling! and sumatriptan *4mitre,was de#eloped to treat migraine headaches.7rug administration depends on the drug type andthe re5uired dose. Dome drugs are not absorbed #ery wellfrom the stomach and must be in$ected or administeredintra#enously. 4n$ections and intra#enous administrationmay also be used when high doses are needed or if anindi#idual is nauseous. :ollowing surgery and other medicalprocedures! patients may ha#e the option of controllingthe pain medication themsel#es. 6y pressing a button!they can release a set dose of medication into anintra#enous solution. This procedure has also beenemployed in other situations re5uiring pain management.nother mode of administration in#ol#es implantedcatheters that deli#er pain medication directly to thespinal cord. 7eli#ering drugs in this way can reduce sideeects and increase the eecti#eness of the drug.44PA/-A'123'A1 P"34S. (ain treatmentoptions that do not use drugs are often used as ad$unctsto! rather than replacements for! drug therapy. Ane of thebenets of non'drug therapies is that an indi#idual canta)e a more acti#e stance against pain. 9elaation techni5ues!such as yo!a and meditation! are used todecrease muscle tension and reduce stress. Tension andstress can also be reduced through *iofeed*ac! inwhich an indi#idual consciously attempts to modify s)intemperature! muscle tension! blood pressure! and heartrate.(articipating in normal acti#ities and eercising canalso help control pain le#els. Through physical therapy!an indi#idual learns benecial eercises for reducingstress! strengthening muscles! and staying t. 9egulare6ercise has been lin)ed to production of endorphins! thebodyBs natural pain )illers.Ac%p%nct%re in#ol#es the insertion of small needles

into the s)in at )ey points. Ac%press%re uses these same)ey points! but in#ol#es applying pressure rather thaninserting needles. 6oth of these methods may wor) byprompting the body to release endorphins. pplying heator being massaged are #ery relaing and help reducestress. Transcutaneous electrical nerve stim%lation*THED, applies a small electric current to certain parts ofner#es! potentially interrupting pain signals and inducingrelease of endorphins. To be eecti#e! use of THED

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should be medically super#ised.347AS37 P/'#/S.There are three types ofin#asi#e procedures that may be used to manage or treatpain; anatomic! augmentati#e! and ablati#e. These proceduresin#ol#e surgery! and certain guidelines should befollowed before carrying out a procedure with permanent

eects. :irst! the cause of the pain must be clearly identied.Eet! surgery should be done only if nonin#asi#eprocedures are ineecti#e. Third! any psychologicalissues should be addressed. :inally! there should be areasonable epectation of success.natomic procedures in#ol#e correcting the in$uryor remo#ing the cause of pain. 9elati#ely commonanatomic procedures are decompression surgeries! suchas repairing a erniated dis in the lower bac) or relie#ingthe ner#e compression related to carpal t%nnel syndrome.nother anatomic procedure is neurolysis! alsocalled a ner#e bloc)! which in#ol#es destroying a portionof a peripheral ner#e.ugmentati#e procedures include electrical stimulationor direct application of drugs to the ner#es that aretransmitting the pain signals. Hlectrical stimulationwor)s on the same principle as THED. 4n this procedure!instead of applying the current across the s)in! electrodesare implanted to stimulate peripheral ner#es or ner#es inthe spinal cord. ugmentati#e procedures also includeimplanted drug'deli#ery systems. 4n these systems!catheters are implanted in the spine to allow direct deli#eryof drugs to the EDand diagnostic tests to determine underlying causes.Dome e#aluations re5uire assessments from se#eral #iewpoints!including neurology! psychiatry and psychology!and physical therapy. 4f pain is due to a medical procedure!management consists of anticipating the type andintensity of associated pain and managing it preempti#ely

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