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Introduction

Chronicmyofascialpainisaconditionthataffectsthefascia,theconnectivetissuethatcoversthemuscles,hencethetermmyofascial.Itischaracterisedbytriggerpointsinthemusculatureandisthemostcommoncauseofmusculoskeletallowerbackandneckpain.Myofascialpainsyndrometypicallyoccursafteramusclehasbeencontractedrepetitivelyorbecauseofstress-relatedmuscletension.Indentistry,triggerpointsinthemasticatoryandcertainneckmusclescanmanifestasdentalpain,temporomandibularjoint(TMJ)dysfunctionandsinusproblems.Thesetriggerpoint-inducedconditionscanbeincrediblydebilitatingbecausetheiroriginsaredifficulttoidentify.Theycanberesponsibleforchronicpainthatseemstohavenomeansofrelief,whichcanultimatelyresultindepression.Here,theauthorwillattempttoexploretheinterrelationshipsbetweenmyofascialpainanddentistryandgivepracticaladvicesothatdentistscanmanagetheintriguingsymptomsofmyofascialoriginmoreeffectively.

So,whataretriggerpoints?

Theterm‘triggerpoint’wascoinedbyDrJanetTravellin1942todescribepainfulnodulesfeltwithintightbandsofmuscle.Theyaresoubiquitousthattheycanoccurinanyofthe700+musclesinourbodies–evenbabieshavethem.Unlikeacupuncturepoints,triggerpointsaremicrocontractionknotswithinamusclefibrethatcanbephysicallyfeltwiththefingers.Theyshould,however,notbeconfusedwithmusclespasmswhichaffecttheentiremuscle,andtheyarenotthesameastenderpointsinpatientswithfibromyalgiawhosufferfromwidespreaddiffusemusculoskeletalpain.

IdiopathicdentalconditionsandthepotentialinvolvementoftriggerpointsDrJamesTang,CES,MBA,BDS,LDSRCSGDP,NASMCorrectiveExerciseSpecialist,Level3PersonalTrainer(REPregistrationnoR1045463),SportsNutritionist&Level3SportsMassageTherapist,withspecialinterestinposturaldysfunctionandlowerbackproblems

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Theeffectoftriggerpointsinthehostmuscles

• Theyarehyperirritablespotslocatedwithinskeletalmuscleandfeellikenodulesonpalpation;whencompressed,theycauseasignificantamountofpain.

• Essentially,partofthemusclefibreiscontractedintoasmallthickenedareaandtherestofthefibreisstretched.Themusclefibresaffectedarenotavailableforcontractionastheyarealreadycontracted,makingthehostmuscleweak.Asaresult,musclescontainingtriggerpointsarefatiguedmoreeasilyanddonotreturntoarelaxedstateasquicklywhenmusclecontractionceases.

• Thecontractedtissuesrestrictbloodandlymphaticcirculationintheirimmediatevicinity,resultinginaccumulationofmetabolicby-productsanddeprivationofoxygenandnutrients.Thiscrisisofenergyproducessensitisingsubstancesthatcancausepain,e.g.bradykinin,whichisknowntoactivatethemuscle’snociceptors.

• Triggerpointswillnotdisappearwithoutintervention;theyaccumulateoveralifetimeandcanexistindefinitelyinalatentstate.Althoughtheactualpainmaysubsidewithinaweekorso,activetriggerpointssimplyturnlatentandcanbereactivatedeasily.

• Latenttriggerpointsarethemaincauseofstiffjointsandtherestrictionofarangeofmovementsduetomuscletightnessandweaknessofthehostmuscle.Theycanalsokeepmusclesoutofbalance,causingjointstoclickduringfunction,andcanpotentiallyleadtoosteoarthritis.

• Activetriggerpointsusuallyreferpainlocallyand/ortodistantareasofthebody,andcommonpatternshavebeenidentified,butthesereferralpatternsdonotnecessarilyconformtothenervepathways.Asthemajorityoftriggerpointsarenotlocatedwhereyoufeelsymptoms,treatingthepainfulareawillnotprovide

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relief.Tocomplicatethesituationfurther,theycanalsomanifestinsecondarymusclesorassatellitetriggerpointsinandaroundthevicinityoftheprimarysite.

• Triggerpointshavebeenimplicatedinarangeofconditionsandtheycanoftenmimicthesymptomsofothers.Theycancausediversesymptomsthatarenotnormallyassociatedwithmuscularproblems.Manytypesofjointpainaremistakenlydiagnosedasarthritisortendonitis.

Physiologyoftriggerpoints

Musclecontractionbeginswiththetwocontractileproteins,myosinandactin,arrangedinaseriesofcompartmentscalledsarcomeresthatrunthelengthofthemyofibril.Theactinisanchoredtotheendandthemyosinsitswithinthemiddleofthesarcomere,pullingtheactinfromeitherendtowardsthemiddletogeneratetension(slidingfilamenttheoryofmusclecontraction).Duringmuscularcontraction,themyosinheadsattachthemselvestotheactinfilamentandrotate,pullingonthesefilaments.

Muscleswithtriggerpointsmanifestintheregionwheresarcomeresandmotorendplatesbecomeoveractive.Theactinandmyosinmyofilamentssittingwithinataughtbandstopslidingoveroneanother.Thecurrenthypothesisabouttheformationoftriggerpointsinvolvesthe“energycrisiscomponent”.

Whenthenerveimpulsearrivesatthemotorendplate,neurotransmitteracetylcholineisreleasedcausingcalciumtobereleasedfromthesarcoplasmicreticulum(SR)andthemusclefibreinvolvedtocontract.Normally,whencontractionofthemusclefibreceases,themotorendplatestopsreleasingacetylcholineandthe“calciumpump”intheSRrecyclecalciumbackintotheSR.

Wherethereisanexcessivemotorendplatereleaseofacetylcholine,surpluscalciumcanbereleasedbytheSRcausingamaximalcontractureofasegmentofmuscle,leadingtomaximalenergydemandandimpairmentoflocalcirculation.Asaresultofthisdeprivationoffuelandoxygen,thecalciumpumpisunabletoreturncalciumbackintotheSR,andthemusclefibrecontinuestocontract,creatingtriggerpoints.Thisviciouscircleisself-perpetuatingunlessthereissomeformofintervention.Furthermore,theattachmentsitesofthesetightmusclefibrescanalsobecometenderastheyarestressedbythecontractioninthecentreofthefibre.

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Whydowegettriggerpoints?

Activetriggerpointsareoftencausedbyaninjury,prolongedpoorpostureorrepetitiveuse.Itisbelievedthattriggerpointsarepartofourprotectivemechanism.Anychangeinmusclebiomechanicsovertimecanmanifestasareasoftightmuscles,andbecausetriggerpointsmakethehostmusclesweak,theyareausefulmechanismforrapidlyswitchingoffmusclepoweraroundaninjury.Thisisessentialif,forexample,thereisafracture.Myofascialmusclepainisthereforeakeypartofourprotectivemechanismbecausepainisavaluablealarmbellthatwarnsofaproblem.

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Therelevanceoftriggerpointsindentistry

Headandnecksymptomscausedbytriggerpointsinclude,butarenotlimitedto,toothache,hypersensitivity,malocclusion,TMJdysfunction,trismusandsinuspain.Triggerpointscancausediversesymptomssuchasblurredvision,dizziness,vertigo,dryeyesandbalanceproblems.Theycanalsocausenumblips,painfultongueanddroopingeyelid(TravellandSimons,1999,308–316).

Temporomandibularjoint(TMJ)dysfunction

TheTMJisasynovialjointbetweenthearticulationofthetemporalboneofthecraniumandthemandible.

ThesymptomsofTMJdysfunctioncanvaryfrommildoccasionaldiscomforttofrequentandextrememisery.AlthoughtriggerpointsareofteninvolvedinTMJdisorders,theyarenotalwaystheprimarycausebecausetheycandevelopsecondarytoconditionssuchasTMJsynovitisandarthritis.Whateverthecause,thepresenceoftriggerpointscanexacerbatethecondition,worsentheprognosisandinterferewithprimaryinterventions.

Thevariousmusclesthatcontroljawfunctionhavetoworkinsynchronyforoptimalmasticatoryperformance.Triggerpointsinthemasticatorymusclesofthejawandanteriorneck,suchasthesternocleidomastoid,aretypicallyinvolvedwiththesymptomsassociatedwithTMJdisorders,includingjawclicking,dislocation,trismusandmalocclusion(TravellandSimons,1999,379–384).

Furthermore,ifthelateralpterygoidistightorshortenedbytriggerpoints,thiscaneasilyleadtomisalignmentofthejaw,causingmalocclusionandassociatedproblems.Amazingly,triggerpointsthatcauseTMJproblemsmayalsocauseotherdiversesymptomssuchasvertigo,visiondisorders,tinnitus,itchinessdeepintheear,sinusissues,toothacheandmore!TheinvolvementoftriggerpointsinthesemusclesshouldnotberuledoutifapatientissufferingfromTMJsymptoms.

PracticaladviceonthemanagementofmyofascialTMJconditions

Principlesofmanagementarebasedonanaccuratediagnosisandshouldbenon-invasiveandreversible.Theobjectiveistocontrolpain,relaxmusclesanderadicatethecausativetriggerpoints.Althoughacombinationoftreatmentisoftenrequired,itispossibletoeradicatethesymptomssimplybyusing

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myofascialreleasetechniquestoremovetheculprittriggerpointsintheinvolvedmuscle(s).

Athoroughclinicalexamination,history-takingandradiographyshouldbeusedtoexcludeanypathologyintheTMJbecausestructuralchangesareusuallyabsentinmyofascialpain.

ItmaybenecessarytoreferyourpatientsforbehaviouralorpsychologicalassistancebecausethereisoftenastrongcorrelationbetweenTMJproblemsandvarioustypesofemotionalstress.Bruxismiscommonandmanypatientsexhibitnocturnalteethgrinding.Toavoidadditionalanxiety,itisimportanttoreassurethemthattheirconditionisoftenself-limiting.Generaladviceshouldalsorecommendtheavoidanceofrepetitivejawmovement(constantchewingovertaxesthemasticatorymuscles)andprolongedjawopening,aswellasasoftdiet.

Externalapplicationofheatcanberecommendedasthisincreasesbloodandlymphaticcirculationtomusclesthathavebeenaffectedbytriggerpoints.

Althoughtriggerpointsinmasticatorymusclescanresultinmalocclusion,poorocclusalbalancecanpredisposetomuscleimbalancesandthereforerectificationoftheprecipitatingocclusalproblemsmayhelptopreventrecurrenceofproblems.Softsplinttherapycanbeusedtodampentheimpactofjawclenchingandreducemuscleactivity.

Nevertheless,allthesemeasuresofferonlysymptomaticreliefandwillnoteradicatethetriggerpointsinvolved.Myofascialtherapyistheonlywaytogetridofthetriggerpoints.

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Practicaladviceonthemanagementof‘dental-related’myofascialtriggerpoints

Triggerpointsinthepterygoidmuscles

ThesetriggerpointsareafrequentcauseofpainintheTMJbutunfortunatelytheyarewellhiddenbythemandible,makingitdifficulttoaccessfortreatment.

Themedialpterygoid

Anatomy–thismuscleoriginatesfromthemedialsurfaceofthelateralpterygoidplateofthesphenoidbone,thepyramidalprocessofthepalatineboneandthemaxillarytuberosity.Itinsertstothemedialsurfaceoftheramusandtheangleofthemandible.

Action–elevatesandprotrudesthelowerjaw.

TriggerpointsinthemedialpterygoidrestrictjawopeningandcancausepainintheTMJ.Paincanbereferredtothehardpalateandtongue,makingswallowingpainful.

Treatment–itispossibletomassagethemedialpterygoidextra-orallybypressingupwithyourthumbinsidetheinneredgetowardsthebackofthemandible.

Thelateralpterygoid

Anatomy–thesuperiorheadoriginatesfromthelateralsurfaceofthegreaterwingofthesphenoidandinsertstothecapsuleandarticulardiscoftheTMJ.Theinferiorheadoriginatesfromthelateralsurfaceofthelateralpterygoidplateofthesphenoidandinsertstotheneckofthemandible.

Action–protrudesthemandible,opensthemouthandmovesthemandiblefromsidetoside.

TriggerpointsinthismusclearetheprimesourceofmyofascialpainandTMJdysfunction.Constanttriggerpoint-generatedtensionheretendstopullthemandibleforward,makingtheTMJclickandpossiblyevendislocatingthejoint.Triggerpointscandevelopinthismuscleasaresultofrepetitivebiting,teethgrinding,prolongedjawopeningduetodental

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workorbreathingdifficulties,emotionalstress,thumbsucking,nailbitingorocclusalmalalignment.Paincanalsobereferredtothecheekandcanmimicsinuspain(aswiththemasseter).

Triggerpointsinthemasseterandtemporaliscanpredisposetosatellitetriggerpointsdevelopinginthelateralpterygoidbymakingthemworkhardertoopenthemouth.Treatment–massagethelateralpterygoidintra-orallywiththeindexfinger.Thefingertipshouldseekthedeeppocketposteriortotheuppermolarsthenpushbothinwardandupwardusingtiny,shortstrokes.Iftriggerpointsarepresent,thiscanbeexcruciatinglypainful.

Sternocleidomastoid(SCM)triggerpoints

Triggerpointsinthismusclecancauseanincredibleamountofpain(butitisallreferredelsewhereandthemusclesthemselvesrarelyhurt)andabewilderinglydiversesetofsymptoms,includingheadache,drycough,sorethroat,sinuspain,excessiveeyetearing,visualdisturbancesanddizziness.Anatomy–theSCMoriginatesfromthemastoidprocesswiththesternaldivisionrunsdiagonallydownwardstoattachtothesternum.Theclaviculardivisionattachesontothemedialaspectoftheclavicle.Action–unilateralcontractionturnstheheadtowardstheoppositesidewhilstbilateralcontractionflexestheneckandtranslatestheheadforward.Characteristics–triggerpointsinthesternaldivisionreferpaindeepintheorbit,TMJ,backandtopofthehead.Theclaviculardivisionreferspaintotheforehead,earandipsilateralmolarteeth.Itisunusualfortriggerpointsononesidetoreferpaintothecontralateralside,butfrontalheadachescausedbyclaviculartriggerpointscanbecross-referredtotheoppositesideoftheforehead.TriggerpointsintheSCMarefrequentlysponsoredbytriggerpointactivitiesintheuppertrapezius–typicallyinducedbyaforwardheadposturewhentheseneckextensorshavetoremainconstantlycontractedtosupporttheweightofthehead.

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Management–triggerpointsinthesternocleidomastoidcanbesotendertopressurethattheycanbemistakenfortenderlymphnodes.Tomassagethesternocleidomastoid,gripthemusclesbetweenyourfingersandkneadfirmly.Searchfortriggerpointsineachofthetwobranches,startingupbehindtheearlobe,allthewaydowntotheclavicle.Pleasebewarethecarotidarteriesandavoidmassagingwhereyoucanfeelapulse,highupunderthechinalongsidethetrachea.

Massetertriggerpoints

Anatomy–themasseterisapowerfulmuscleofmasticationconsistingofasuperficialanddeephead,bothoriginatingfromthezygomaticarch.Thesuperficialpartinsertsonthemassetertuberosityattheoutersurfaceofthemandibularanglewhereasthedeeppartrunsfurtherdorsallytotheoutersurfaceoftheramusofthemandible.

Characteristics–thoseinthedeeplayeranteriortotheearcancausepainintheTMJ.Massetertriggerpointscanincreasemuscletensionsomuchthatitcanresultintrismus.

Triggerpointsinthesuperficialmasseterinthemiddleofthemusclebellycausetoothachethatresemblesdentalabscesspain.Patientscanusuallypinpointtheirtoothacheintheirlowermolars.Triggerpointsinthesuperficialmasseterjustbelowthezygomaticarchgivepatientsafeelingoftoothachethatextendsupintotheroots,withsensitivityintheirupperpremolarsandfirstuppermolar.Painistypicallyworseintheearlymorningorearlyevening.LikemanyofthetriggerpointsintheTMJmusculatures,thisoneisactivatedbyunevenandrepetitivechewingorbitingonhardobjects(suchasregularnailbiting).Theseunpleasantsymptomscanbeavoidedbygivingupthesehabits.Misinterpretationofthesesymptomscanresultinunnecessaryandirreversibledentalprocedures,suchasextraction.Thesecondaryeffectofmassetertriggerpointsisthattheymaycausepatientstoneglectbrushingduetohypersensitivity,leadingtodeteriorationoftheiroralhealth.Triggerpointsinthemassetercanalsocausepaininthefrontoftheface,undertheeyesorovertheeyebrows,symptomsoftenmistakenforsinusitis.

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Practicaladviceoneradicatingtriggerpointsinthemasseter:thetriggerpointsareinthebellyofthemasseterjustbehindtherootsoftheteeth.Pressingonthisknottedmusclecanusuallyreproducethesymptomsintheteeth.Massagethemasseterwithtwofingers,oneinsideandoneoutside,withyourthumbinsidethemouth,andkneadthemusclebetweenyourthumbandfingers.Seekouteachexquisitelytenderknot,fromthemaxillatothebottomofthemandible,andmassageitasstronglyasisbearable.Alternatively,applyfirmbutconstantpressureonthetriggerpointuntilthepainsubsides.Repeatedtreatmentmayberequiredforstubborntriggerpointstocompletelyrelease.

Temporalistriggerpoints

Anatomy–thetemporalisisalarge,thin,fan-shapedmasticatorymusclelocatedinthesideoftheskullaboveandinfrontoftheear.Itoriginatesfromthetemporalandinfratemporalcrest,passingbeneaththezygomaticarchandinsertingintothecoronoidprocessandtheanteriorramusofthemandible.Itelevatesandretractsthemandible.

Causesoftemporalistriggerpoints–masticatorymusclesareeasilyoverloaded,especiallywhenweclenchorgrindourteeth(bruxism)whichcanactivatetriggerpointsinthemuscle,ortriggerpointsinthemusclecancausebruxism.Inbothcases,thetemporalisbecomesoverworkedandstrained.

Triggerpointscanresultfromprolongedjawopeningduetodentaltreatment:extensivedentalworkleadstotriggerpointsinthetemporalismuscle,addingtothefacialpainandpost-operativetoothache,leadingtothemistakenassumptionthatfurtherdentalworkisrequired,whichofcourseonlyworsenstheproblem.

Othercausesincludechronicmouthbreathing,excessivegumchewing,acolddraftofaironthesideofthefaceandpoorocclusion.

Characteristics–triggerpointsinthemasseterandsternocleidomastoidsponsorsatellitetriggerpointsinthetemporalisandcaneasilybereactivatedshortlyafterattemptstosubduethem.Furthermore,ahyperkyphoticposture,typicallyrelatedtoaforwardheadposture,canalsoleadtoformationoftriggerpointsinthetemporalis.Unfortunately,muscleshavethistypeofeffectononeanother.Itisthereforeimportanttotrackdownandtreatallthemusclesthatareinterrelatedbyproximityorfunction.

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Temporalistriggerpointsareassociatedwithheadpain.Theyreferpaintotheipsilateralhead,sometimestothefrontoftheheadovertheeyebrow,andtothefaceandupperteeth.Sometimes,paincanbefeltinthesideofthefaceasadiffusejawpainextendingallthewaydowntotheneckregion.Temporalistriggerpointscanalsocausepainandhypersensitivityinthemaxillaryteeth.Diffusepainintheupperteethduringmasticationislikelytobecomingfromthetemporalis.Triggerpointsinthefrontcreatesensitivityinthefrontteethandthoseinthebackcreatesensitivityinthebackteeth.

TemporalistriggerpointsareafeatureofTMJproblemsandchronictriggerpointsinthetemporalisandmassetermusclescancausepermanentstructuraldamagetothesynovialjointoftheTMJ.

Adviceontreatmentoftemporalistriggerpoints–findthetriggerpointsatthefrontofthemusclefirstandbuildupgentlepressure.Thisoftenreproducesthedeeppainthatradiatestotheteeth.Similartothetreatmentofthemassetertriggerpoints,maintainafirmandconstantpressureuntilthepainalleviates.Then,massagetheareagentlyandrepeatwiththenexttriggerpoint.

Topreventthesetriggerpointsfromrecurring,adviseyourpatientstoeradicatecausativefactorssuchasgumchewingorchewinghardsubstances(e.g.fingernails).

Falsesinussymptoms

Triggerpointsinthejawmusclescanmimicthesymptomsofsinusitis.Whenconventionalsinusmedicationdoesnotrelieveapatient’ssinusdiscomfort,itispertinenttoconsidertheinvolvementoftriggerpointsasadifferentialdiagnosis.

Triggerpointsinthefacialmuscles,jawsandfrontoftheneckcancausetheproductionofexcessmucusinthesinuses,nasalcavitiesandthroat,whichcanleadtocontinuingsinusdrainage,constantclearingofthethroat,chroniccough,allergicrhinitis(runnynose),andpersistenthayfeverorcoldsymptoms.

Naturally,allthesewidelyvaryingsymptomscanhavecausesotherthanmyofascialtriggerpoints.Nevertheless,anyexaminationshouldconsidertheinvolvementoftriggerpointsforabnormalandunexplainedsymptomsintheface,earsandjaws.Unfortunately,manydentistsandpatientsarestillill-informedabouttriggerpoints.

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Management–whentriggerpointsarethecauseofsymptomsinthejaws,face,eyes,earsorteeth,significantreliefcanbeobtainedbyapplyingmyofascialreleasetechniques.

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Practicaladviceonthegeneralprincipleofmanagingtriggerpoints

Combinedwithsomesimplelifestylechanges,myofascialreleaseoftriggerpointscanyielddramatic,immediateandsustainableresults.Theobjectivesofsuchtherapiesare:

• Toidentifythecorrecttriggerpoint(s).• Todeactivatethepoint(s)usingmyofascialrelease.• Topreventrecurrence.

Identifythecorrecttriggerpoint(s)

Itisimportanttohavegoodknowledgeoftheanatomyofthemusclestobetreatedbecausealleviatingmyofascialpaindependsonlocatingthetriggerpoints.Thegoodnewsisthattheyalwaysoriginateatthemidpointofamuscle’sfibreswherethemotornerveenters,transmittingthenerveimpulsewhichinitiatesmusclecontraction.Theproblemoccurswhenthefibresdonotalwaysrunfromoneendofamuscletotheother.Theorientationofthefibresinmusclesvaries,dependingontheirdesignatedfunction.Inamusclemadeforspeed,thefibresareparallel,runningstraightfromendtoend,anditstriggerpointsareeasilyfoundhalfwayalong.However,musclesthataremadeforpower,likethemasticatorymuscles,havetheirfibresrunningdiagonallyatsomeangletoitslength.Sincetriggerpointsmaybefoundinthecentreofeachindividualfibre,theymaybesituatedanywherealongthemuscle.Thatsaid,triggerpoints(active/latent)arerelativelyeasytolocatebecausetheyarealwaysverypainfulonpalpation.

Anotherproblemwithtreatingtriggerpointsisthattheytypicallyreferpaintoanothersiteandworkingontheareawherethepainisfeltwillnotofferpainrelief.Fortunately,thereferralpatternisreproducibleandwelldocumented.Thepatternofreferralcanbeeasilyreproducedwhenthetriggerpointispressed.Tocomplicatethematterfurther,triggerpointsinthesternocleidomastoidanduppertrapeziuscansponsorsatellitetriggerpointsinthemasticatorymusclesandunlessthese‘primary’triggerpointsarealsodealtwith,simplyeradicatingthoseinthesatellitesitesmaynotproducethedesiredlong-lastingeffects.Itisthereforeimportanttotrackdownandtreatallthemusclesthatareinterrelatedbyproximityorfunction.Musclesdonotoperateinisolation–thisexplainswhy

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developmentofprimary,centraltriggerpointsinoneareaofthebodymayleadtosecondaryorsatellitetriggerpointsdistally.

Usingappropriatetechniquestodeactivatethepoint(s)

Eradicatingthesetriggerpointscompletelyusuallyrequiresmultipletreatmentsessions,dependingonthemuscleinquestionandtheirritabilityofthetriggerpointsinvolved–uptofivetimesadayforaweekorsomayberequired.Persistencepaysoff.Clearlyitisimpracticalfordentiststobealwaysinvolvedsoitisadvisabletoinstructpatientstocarryoutself-myofascialreleasesothattheycanmangetheirowntriggerpointsinthecomfortoftheirhome.

However,beforeattemptingtotreatpatients,youshouldfamiliariseyourselfwiththeeffectofself-myofascialrelease.Thebestplacetostartistorunyourfingersalongyourquadriceps–youwillalmostcertainlybeabletofeelnumerous‘nodules’thatarepainfultofirmpressure.Applyingathinlayerofcreamoroilwillhelpyourfingertoglidealongtheskin.Youshouldusethethumbofonehandsupportedbythethumboftheother.Onceyoucanfeeltheknot,pressonitfirmly(ischemiccompression)untilyoucanfeelthepain(intensity7/10;ifyouapplytoomuchpressureandcausetoomuchpain,yourmuscleswillcontractunnecessarily).Maintainthesamepressureuntilthepaindissipates(thisusuallytakes30–60seconds).Unlikethetriggerpointsinthemasticatorymuscleswhichcanbeeasilymanipulatedwiththefingers,fingerpressuremaynotbeadequateonthethickmusclesofthelegsandyoumayrequiretoolssuchasfoamrollers.

Myofascialreleasewithdeepstrokemassagescanalsobeused.Theyworkbybreakingintothechemicalandneurologicalfeedbackloopthatmaintainsthemicromuscularcontraction.Theyalsoincreasethecirculationthathasbeenrestrictedbythecontractedtissue.Massageshouldbedeepandinonedirectiononly(donotattempttorubthetriggerpointstoandfro)andthepaceshouldbeslowbecausetheaimistodeactivateoveractivetissueandnothingshouldbedonetomakethetissuemoreexcited.

Youmaybetemptedtodiscontinueworkingonthetriggerpointthemomentitstopsactivelyreferringpain.However,ifthetriggerpointstillhurtswhenyoupressonit,youhaveonlysootheditintoalatentstatewhichcanbeeasilyreactivatedwiththeslightestoverload,suchasbitingheavilyorrepetitivechewing.

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ThesciencebehindthisinvolvesautogenicinhibitionbyactivatingtheGolgitendonorganslocatedinthemusculotendinousjunctions.SkeletalmusclecontainsmusclespindlesandtheGolgitendonorgans,twoneuralreceptors.Musclespindlesaresensitivetoachangeandrateofmusclebeingstretched.Whenstimulated,theywillgenerateastretchreflexthatcausesthemuscletocontract.TheGolgitendonorgansarestimulatedbyachangeandrateoftension;thisstimulationcausesthemuscletorelax.Whenachangeintensionissustainedatanadequateintensityandduration,musclespindleactivityisinhibitedcausingadecreaseintriggerpointactivity,allowingthemusclefibrestostretch,unknotandrealign.

Note,therearecertainmedicalcontraindicationsfortriggerpointtherapy,suchas,butnotlimitedto,infectiousskinconditionsintheareainvolved,heartfailure,oranyotherorganfailure,andcancer.

Preventionstrategies

Althoughachesandpainsfromtriggerpointsarecommon,therecanoftenbeanunderlyingpathology.Itisequallyimportanttoidentifythecausativefactorsofthesetriggerpointsastheyrarelydevelopinisolationandmayreturniftheunderlyingcauseisnotidentifiedandaddressed,whetheritbeaforwardheadposture,repetitivechewingactions,bruxismorfaultyocclusionetc.Ifthesearenotrectified,symptomscansimplyrecur.

SummaryThisarticlehighlightsthediversityofsymptomsthatcanbecausedbytriggerpoints.Asaconsequence,itispossibletoconsidertheirinvolvementasadifferentialdiagnosisforapatient’sdentalconditions.

Presentingsymptoms Likelylocationoftriggerpoint(s)

Bruxism TemporalisTrismus Masseter

ZygomaticusmajorTMJdysfunctionsyndrome Pterygoidmuscles

MasseterSinussymptoms Sternocleidomastoid

Lateralpterygoid

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Toothacheandhypersensitivity ClavicularbranchofsternocleidomastoidUppertrapeziusMasseterTemporalisLonguscapitis(oneoftheneckflexors)