Idiopathic dental conditions and the potential involvement ... · These trigger point-induced...
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1 Introduction Chronic myofascial pain is a condition that affects the fascia, the connective tissue that covers the muscles, hence the term myofascial. It is characterised by trigger points in the musculature and is the most common cause of musculoskeletal lower back and neck pain. Myofascial pain syndrome typically occurs after a muscle has been contracted repetitively or because of stress- related muscle tension. In dentistry, trigger points in the masticatory and certain neck muscles can manifest as dental pain, temporomandibular joint (TMJ) dysfunction and sinus problems. These trigger point-induced conditions can be incredibly debilitating because their origins are difficult to identify. They can be responsible for chronic pain that seems to have no means of relief, which can ultimately result in depression. Here, the author will attempt to explore the interrelationships between myofascial pain and dentistry and give practical advice so that dentists can manage the intriguing symptoms of myofascial origin more effectively. So, what are trigger points? The term ‘trigger point’ was coined by Dr Janet Travell in 1942 to describe painful nodules felt within tight bands of muscle. They are so ubiquitous that they can occur in any of the 700+ muscles in our bodies – even babies have them. Unlike acupuncture points, trigger points are micro contraction knots within a muscle fibre that can be physically felt with the fingers. They should, however, not be confused with muscle spasms which affect the entire muscle, and they are not the same as tender points in patients with fibromyalgia who suffer from widespread diffuse musculoskeletal pain. Idiopathic dental conditions and the potential involvement of trigger points Dr James Tang, CES, MBA, BDS, LDS RCS GDP, NASM Corrective Exercise Specialist, Level 3 Personal Trainer (REP registration no R1045463), Sports Nutritionist & Level 3 Sports Massage Therapist, with special interest in postural dysfunction and lower back problems
Transcript of Idiopathic dental conditions and the potential involvement ... · These trigger point-induced...
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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)
