LinköpingȱUniversityȱMedicalȱDissertationsȱ No.ȱ998ȱ
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PelvicȱGirdleȱPainȱandȱLumbarȱPainȱ inȱRelationȱtoȱPregnancyȱ
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AnnelieȱGutkeȱ
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DepartmentȱofȱHealthȱandȱSociety,ȱDivisionȱofȱPhysiotherapyȱ FacultyȱofȱHealthȱSciencesȱ
LinköpingȱUniversity,ȱSwedenȱ ȱ
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Linköpingȱ2007ȱ ȱ
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¤AnnelieȱGutke,ȱ2007ȱ annelie.gutke@ihs.liu.se http://www.ihs.liu.seȱ ȱ
Coverȱpicture/illustration:ȱMarjutȱMolénȱ ȱ
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Publishedȱarticleȱhasȱbeenȱreprintedȱwithȱtheȱpermissionȱofȱtheȱcopyrightȱholder.ȱ ȱ
PrintedȱinȱSwedenȱbyȱUniTryck,ȱLinköping,ȱSweden,ȱ2007ȱȱ ȱ
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ISBNȱ978Ȭ91Ȭ85715Ȭ14Ȭ5ȱȱ ISSNȱ0345Ȭ0082ȱ
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ȱ ȱ ȱ ȱ ȱ ȱ ȱ ToȱJanne,ȱ
JuliaȱandȱJanelleȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ
“Nothingȱinȱscienceȱhasȱanyȱvalueȱtoȱsocietyȱifȱitȱisȱnotȱcommunicated.”ȱ
ȱ ȱ ȱ ȱ ȱ ȱ ȱ ȱ AnneȱRoeȱ
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CONTENTSȱ
ABSTRACT ... 1
LISTȱOFȱPAPERS ... 3
ABBREVIATIONS... 4
DEFINITIONS... 5
INTRODUCTION... 7
BACKGROUND... 8
TERMINOLOGY... 8
EPIDEMIOLOGY ... 9
Prevalenceȱofȱlowȱbackȱpainȱinȱwomen... 9
Courseȱandȱpredictorsȱofȱlowȱbackȱpain... 10
PREGNANCYȬRELATEDȱPELVICȱGIRDLEȱPAINȱANDȱLUMBARȱPAIN 11 Classificationȱofȱlowȱbackȱpain ... 12
CAUSESȱOFȱPREGNANCYȬRELATEDȱPELVICȱGIRDLEȱPAIN ... 14
Muscleȱfunctionȱinȱrelationȱtoȱlumbopelvicȱstability... 15
Gait ... 17
CONSEQUENCESȱOFȱPREGNANCYȬRELATEDȱLOWȱBACKȱPAIN ... 17
HealthȬrelatedȱqualityȱofȱlife... 18
Pain... 18
Disability ... 20
DEPRESSION ... 21
Postpartumȱdepression ... 21
AIMSȱOFȱTHEȱTHESIS... 23
MATERIALSȱANDȱMETHODS... 24
DESIGN ... 24
STUDYȱPOPULATION... 26
MEASUREMENTSȱANDȱPROCEDURES ... 26
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SelfȬreportedȱquestionnaires ... 26
HealthȬrelatedȱqualityȱofȱlife ... 27
Pain... 27
Disability... 28
Postpartumȱdepression... 29
Classificationȱofȱtheȱcohort ... 29
Criteriaȱforȱtheȱcohortȱclassification ... 31
Reliabilityȱofȱtheȱclassificationȱprocedure ... 32
Physicalȱfunctioning ... 32
Backȱflexorȱmusclesȱendurance ... 33
Backȱextensorȱmusclesȱendurance ... 33
Maximalȱvoluntaryȱisometricȱhipȱextension ... 34
Gaitȱspeed... 34
STATISTICALȱANALYSES ... 35
ETHICALȱCONSIDERATIONS ... 38
RESULTS ... 39
PREVALENCEȱOFȱLOWȱBACKȱPAINȱINȱPREGNANCYȱANDȱ POSTPARTUM... 39
DropȬoutȱanalysis... 42
THEȱCOURSEȱOFȱLOWȱBACKȱPAIN ... 44
PREDICTORSȱFORȱPELVICȱGIRDLEȱPAINȱORȱCOMBINEDȱPAIN... 45
HEALTHȬRELATEDȱQUALITYȱOFȱLIFEȱINȱEARLYȱPREGNANCY ... 45
PAINȱANDȱDISABILITYȱINȱEARLYȱPREGNANCY ... 47
POSTPARTUMȱDEPRESSIVEȱSYMPTOMS ... 47
PHYSICALȱMEASURESȱINȱPREGNANCYȱANDȱPOSTPARTUM ... 49
Backȱflexorȱmusclesȱendurance... 49
Backȱextensorȱmusclesȱendurance ... 49
Maximalȱvoluntaryȱisometricȱhipȱextension ... 51
Gaitȱspeed ... 51
Painȱintensityȱinȱrelationȱtoȱphysicalȱmeasures ... 51
DISCUSSION ... 53
PREVALENCEȱOFȱLOWȱBACKȱPAINȱINȱPREGNANCYȱANDȱ POSTPARTUM... 53
Power... 54
Classificationȱofȱlowȱbackȱpain ... 55
COURSEȱANDȱPREDICTORS ... 58
HEALTHȬRELATEDȱQUALITYȱOFȱLIFE,ȱPAINȱANDȱDISABILITY... 62
MeasuresȱofȱhealthȬrelatedȱqualityȱofȱlifeȱandȱdisability ... 63
POSTPARTUMȱDEPRESSION ... 64
MUSCLEȱFUNCTION... 66
INTERNATIONALȱCLASSIFICATIONȱOFȱFUNCTIONING,ȱDISABILITYȱ ANDȱHEALTH... 68
CLINICALȱIMPLICATIONS... 71
FUTUREȱRESEARCH... 71
CONCLUSIONS ... 73
SUMMARYȱINȱSWEDISH... 74
ACKNOWLEDGEMENTS ... 76
REFERENCES ... 78 ȱ
ABSTRACTȱ
Theȱprevalenceȱofȱlowȱbackȱpainȱ(LBP)ȱisȱhigherȱinȱpregnantȱwomenȱcomparedȱ toȱ womenȱ ofȱ theȱ sameȱ ageȱ inȱ aȱ generalȱ population.ȱ PregnancyȬrelatedȱ LBPȱ persistsȱ 6ȱ yearsȱ afterȱ pregnancyȱ inȱ 16%ȱ ofȱ women.ȱ Consequently,ȱ pregnancyȱ representsȱaȱspecificȱriskȱforȱLBPȱandȱpersistentȱLBP.ȱPregnancyȬrelatedȱLBPȱisȱ usuallyȱ studiedȱ asȱ aȱ singleȱ entity,ȱ however,ȱ onlyȱ oneȱ subgroupȱ ofȱ LBP,ȱ i.e.ȱ pelvicȱgirdleȱpainȱ(PGP),ȱseemsȱtoȱbeȱassociatedȱwithȱpregnancy.ȱAccordingly,ȱ possibleȱdifferencesȱinȱsubgroupsȱofȱpatientsȱwithȱLBPȱareȱunknown.ȱ
ȱ Theȱaimsȱofȱthisȱthesisȱwereȱtheȱfollowing:ȱ1)ȱtoȱdescribeȱtheȱprevalenceȱofȱ clinicallyȱclassifiedȱsubgroupsȱofȱwomenȱwithȱLBPȱinȱaȱcohortȱ(noȱLBP,ȱlumbarȱ pain,ȱPGP,ȱandȱcombinedȱpainȱ(PGPȱandȱlumbarȱpain))ȱduringȱpregnancyȱandȱ postpartum,ȱandȱ2)ȱtoȱdetermineȱifȱthereȱwasȱaȱdisparityȱinȱtheȱcourse,ȱhealthȬ relatedȱqualityȱofȱlifeȱ(HRQL),ȱpainȱintensity,ȱdisability,ȱdepressiveȱsymptoms,ȱ orȱmuscleȱfunctionȱinȱsubgroupsȱofȱtheȱcohort,ȱandȱ3)ȱtoȱidentifyȱpredictorsȱforȱ havingȱpersistentȱpregnancyȬrelatedȱPGPȱpostpartum.ȱ
ȱ ConsecutivelyȬenrolledȱ pregnantȱ womenȱ wereȱ classifiedȱ intoȱ LBPȱ subgroupsȱ byȱ mechanicalȱ assessmentȱ ofȱ theȱ lumbarȱ spine,ȱ pelvicȱ painȱ provocationȱtests,ȱstandardȱhistory,ȱandȱpainȱdrawings.ȱAllȱwomenȱansweredȱ questionnairesȱ (backgroundȱ data,ȱ EQȬ5D).ȱ Womenȱ withȱ LBPȱ completedȱ theȱ Oswestryȱ Disabilityȱ Indexȱ andȱ painȱ measures.ȱ Theȱ Edinburghȱ Postnatalȱ Depressionȱ Scaleȱ wasȱ usedȱ toȱ evaluateȱ depressiveȱ symptomsȱ atȱ 3ȱ monthsȱ postpartumȱ (cutȬoffȱ ǃ10).ȱ Trunkȱ muscleȱ endurance,ȱ hipȱ muscleȱ strength,ȱ andȱ gaitȱspeedȱwereȱinvestigated.ȱMultipleȱlogisticȱregressionȱwasȱusedȱtoȱidentifyȱ predictorsȱfromȱselfȬreportsȱandȱclinicalȱexamination.ȱ
ȱ Atȱ theȱ 12Ȭ18ȱ gestationalȱ weekȱ evaluation,ȱ 118/308ȱ (38%)ȱ womenȱ hadȱ noȱ LBP,ȱ 33ȱ (11%)ȱ hadȱ lumbarȱ pain,ȱ 101ȱ (33%)ȱ hadȱ PGP,ȱ andȱ 56ȱ (18%)ȱ hadȱ combinedȱpain.ȱThreeȱmonthsȱpostpartum,ȱ183/272ȱ(67%)ȱwomenȱhadȱnoȱLBP,ȱ 29ȱ(11%)ȱhadȱlumbarȱpain,ȱ46ȱ(17%)ȱhadȱPGP,ȱandȱ14ȱ(5%)ȱhadȱcombinedȱpain.ȱ PregnantȱwomenȱwithȱcombinedȱpainȱwereȱmostȱaffectedȱinȱtermsȱofȱHRQL,ȱ painȱ intensity,ȱ andȱ disability.ȱ Depressiveȱ symptomsȱ wereȱ threeȱ timesȱ moreȱ prevalentȱ inȱ womenȱ withȱ LBPȱ (27/87,ȱ 31%)ȱ thanȱ inȱ womenȱ withoutȱ LBPȱ (17/180,ȱ 9%).ȱ Womenȱ withȱ PGPȱ and/orȱ combinedȱ painȱ hadȱ lowerȱ valuesȱ forȱ trunkȱ muscleȱ endurance,ȱ hipȱ extensorȱ strengthȱ andȱ gaitȱ speedȱ comparedȱ toȱ womenȱ withoutȱ LBP.ȱ Postpartum,ȱ 16Ȭ20%ȱ ofȱ theȱ womenȱ hadȱ persistentȱ combinedȱ painȱ orȱ PGP,ȱ whereasȱ 1/29ȱ hadȱ lumbarȱ pain.ȱ Predictorsȱ forȱ
persistentȱ PGPȱ orȱ combinedȱ painȱ wereȱ workȱ dissatisfaction,ȱ olderȱ age,ȱ combinedȱpainȱinȱearlyȱpregnancy,ȱandȱlowȱenduranceȱofȱtheȱbackȱflexors.ȱ ȱ Inȱ conclusion,ȱ womenȱ withȱ combinedȱ painȱ wereȱ identifiedȱ toȱ beȱ aȱ targetȱ groupȱ sinceȱ theyȱ hadȱ theȱ lowestȱ recoveryȱ rateȱ andȱ sinceȱ theȱ classificationȱ ofȱ combinedȱ painȱ wasȱ foundȱ toȱ beȱ aȱ predictorȱ forȱ persistentȱ PGPȱ orȱ combinedȱ painȱ postpartum.ȱ Theȱ hypothesisȱ ofȱ anȱ associationȱ betweenȱ muscleȱ dysfunctionȱ andȱ PGPȱ wasȱ strengthened.ȱ Basedȱ onȱ theȱ findingȱ ofȱ highȱ comorbidityȱofȱpostpartumȱdepressiveȱsymptomsȱandȱLBP,ȱitȱseemsȱimportantȱ toȱscreenȱforȱandȱconsiderȱtreatmentȱstrategiesȱforȱbothȱsymptoms.ȱȱ
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ISBNȱ978Ȭ91Ȭ85715Ȭ14Ȭ5ȱ ISSNȱ0345Ȭ0082ȱ
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LISTȱOFȱPAPERSȱ
I. Annelieȱ Gutke,ȱ Hansȱ Christianȱ Östgaard,ȱ Birgittaȱ Öberg.ȱ Pelvicȱ Girdleȱ Painȱ andȱ Lumbarȱ Painȱ inȱ Pregnancy:ȱ Aȱ cohortȱ studyȱ ofȱ theȱ consequencesȱ inȱ termsȱofȱhealthȱandȱfunctioning.ȱSpineȱ2006;ȱ31(5):ȱE149Ȭ155ȱ
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II. Annelieȱ Gutke,ȱ Annȱ Josefsson,ȱ Birgittaȱ Öberg.ȱ Pelvicȱ Girdleȱ Painȱ andȱ LumbarȱPainȱinȱRelationȱtoȱPostpartumȱDepressiveȱSymptoms.ȱAcceptedȱforȱ publicationȱinȱSpineȱJuneȱ1ȱ2007ȱ
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III. AnnelieȱGutke,ȱHansȱChristianȱÖstgaard,ȱBirgittaȱÖberg.ȱMuscleȱfunctionȱ inȱ pregnancyȬrelatedȱ lowȱ backȱ pain.ȱ Aȱ prospectiveȱ cohortȱ studyȱ inȱ earlyȱ pregnancyȱandȱpostpartum.ȱSubmittedȱ
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IV. Annelieȱ Gutke,ȱ Hansȱ Christianȱ Östgaard,ȱ Birgittaȱ Öberg.ȱ Predictingȱ persistentȱpregnancyȬrelatedȱlowȱbackȱpain.ȱSubmittedȱ
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ABBREVIATIONSȱ
ASLRȱ ActiveȱStraightȱLegȱRaisingȱTestȱ BMIȱ BodyȬMassȬIndexȱ
EPDSȱ EdinburghȱPostnatalȱDepressionȱScaleȱ
EQȬ5Dȱ EuropeanȱQualityȱofȱLifeȱ5ȱDimensionsȱQuestionnaireȱ HRQLȱ HealthȬRelatedȱQualityȱofȱLifeȱ
ICCȱ IntraclassȱCorrelationȱCoefficientȱ LBPȱ LowȱBackȱPainȱ
LPȱ ȱ LumbarȱPainȱ(PaperȱI)ȱ
MDTȱ MechanicalȱDiagnosisȱandȱTherapyȱ MICȱ MinimalȱImportantȱChangeȱ
MIDȱ MinimalȱImportantȱDifferenceȱ ODIȱ OswestryȱDisabilityȱIndexȱ ORȱȱ OddsȱRatioȱ
PGPȱ PelvicȱGirdleȱPainȱ
PPGPȱ PregnancyȬrelatedȱ Pelvicȱ Girdleȱ Painȱ (Paperȱ I);ȱ theȱ sameȱ classificationȱasȱPGPȱinȱPapersȱIIȬIVȱ
RCTȱ RandomisedȱControlledȱTrialȱ
RDQȱ TheȱRolandȬMorrisȱDisabilityȱQuestionnaireȱ SFȬ36ȱ TheȱShortȱFormȱ36ȱHealthȱSurveyȱ
SIJȱ ȱ SacroiliacȱJointȱ
VASȱ VisualȱAnalogueȱScaleȱ ȱ
DEFINITIONSȱ
Backȱpainȱ Aȱgeneralȱtermȱusedȱwhenȱtheȱstudyȱreferredȱtoȱdoȱnotȱ specifyȱlocalisation.ȱ
Centralisationȱȱ If,ȱ asȱ aȱ resultȱ ofȱ repeatedȱ movementsȱ orȱ positions,ȱ theȱ radiatingȱ symptomsȱ originatingȱ fromȱ theȱ spineȱ andȱ referredȱ distally,ȱ regressȱ proximallyȱ towardsȱ theȱ lumbarȱ midlineȱ ofȱ theȱ spineȱ (57).ȱ Oppositeȱ ofȱ peripheralisation.ȱ
Clinicalȱnaturalȱcourseȱ Definedȱasȱwithoutȱdirectedȱinterventionȱfromȱtheȱstudyȱ exceptȱforȱevaluationȱofȱlowȱbackȱpainȱ(269).ȱ
Combinedȱpainȱ Affectedȱ byȱ theȱ twoȱ syndromesȱ pelvicȱ girdleȱ painȱ andȱ lumbarȱpain.ȱ
Deliveryȱ ȱ Givingȱbirth.ȱ
Disabilityȱ Aȱgeneralȱtermȱforȱimpairment,ȱactivityȱlimitations,ȱandȱ participationȱ restrictionsȱ fromȱ theȱ problematicȱ aspect,ȱ accordingȱtoȱICFȱ2001ȱ(255).ȱ
Functioningȱ Aȱ generalȱ termȱ forȱ allȱ bodyȱ functions,ȱ activities,ȱ andȱ participationȱ fromȱ aȱ healthyȱ perspective,ȱ accordingȱ toȱ theȱICFȱ2001ȱ(255).ȱ
Lowȱbackȱpainȱ Painȱ andȱ discomfortȱ localisedȱ belowȱ theȱ costalȱ marginȱ andȱaboveȱtheȱinferiorȱglutealȱfolds,ȱwithȱorȱwithoutȱlegȱ painȱ(242).ȱ
Lumbarȱpainȱ Painȱ perceivedȱ asȱ arisingȱ fromȱ anywhereȱ withinȱ aȱ regionȱ boundedȱ superiorlyȱ byȱ anȱ imaginaryȱ transverseȱ lineȱthroughȱtheȱtipȱofȱtheȱlastȱthoracicȱspinousȱprocess,ȱ inferiorlyȱ byȱ anȱ imaginaryȱ transverseȱ lineȱ throughȱ theȱ tipȱ ofȱ theȱ firstȱ sacralȱ spinousȱ process,ȱ andȱ laterallyȱ byȱ verticalȱ linesȱ tangentialȱ toȱ theȱ lateralȱ bordersȱ ofȱ theȱ lumbarȱerectorȱspinaeȱ(151).ȱ
Lumbopelvicȱpainȱ Includingȱ theȱ syndromesȱ pelvicȱ girdleȱ painȱ and/orȱ lumbarȱpainȱ(267).ȱ
NonpregnancyȬȱ
relatedȱlowȱbackȱpainȱ Lowȱ backȱ painȱ presentȱ outsideȱ pregnancyȱ withȱ noȱ ȱ ȱ ȱ knownȱassociationȱtoȱaȱpregnancyȱlikeȱtimeȱofȱdebut.ȱ Pelvicȱgirdleȱpainȱ Painȱ experiencedȱ betweenȱ theȱ posteriorȱ iliacȱ crestȱ andȱ
theȱ glutealȱ fold,ȱ particularlyȱ inȱ theȱ vicinityȱ ofȱ theȱ
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sacroiliacȱ joints.ȱ Theȱ painȱ mayȱ radiateȱ inȱ theȱ posteriorȱ thighȱ andȱ canȱ alsoȱ occurȱ inȱ conjunctionȱ with/orȱ separatelyȱinȱtheȱsymphysisȱ(258).ȱ
Peripheralisationȱ If,ȱ asȱ aȱ resultȱ ofȱ repeatedȱ movementsȱ orȱ positions,ȱ theȱ radiatingȱ symptomsȱ originatingȱ fromȱ theȱ spineȱ andȱ referredȱdistally,ȱprogressȱfartherȱdistallyȱ(57).ȱOppositeȱ ofȱcentralisation.ȱ
Persistentȱpainȱ Painȱpresentȱmostȱofȱtheȱtimeȱorȱrecurrentȱepisodesȱǃ12ȱ weeks.ȱ
Postpartumȱ Afterȱ deliveryȱ (Americanȱ English),ȱ similarȱ toȱ postnatalȱ (BritishȱEnglish).ȱ
Predictorȱvariableȱ Explanatoryȱvariableȱorȱcovariateȱ(6).ȱ PregnancyȬrelatedȱ
lowȱbackȱpainȱ Lowȱbackȱpainȱpresentȱinȱpregnancy.ȱ
Redȱflagȱ Aȱsymptomȱdescribedȱbyȱtheȱpatientȱthatȱmayȱindicateȱ seriousȱpathologyȱ(242).ȱ
Riskȱfactorȱ Aȱ determinantȱ thatȱ influencesȱ theȱ incidenceȱ (relativeȱ risk)ȱ(193).ȱ
Sensitivityȱ Theȱ abilityȱ ofȱ aȱ testȱ toȱ identifyȱ theȱ patientsȱ withȱ theȱ conditionȱ(224).ȱ
Specificityȱ Theȱ abilityȱ ofȱ aȱ testȱ toȱ identifyȱ theȱ absenceȱ ofȱ aȱ conditionȱ(224).ȱ
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INTRODUCTIONȱ
Theȱ startingȱ pointȱ ofȱ thisȱ thesisȱ wasȱ basedȱ onȱ theȱ historiesȱ ofȱ manyȱ womenȱ whoȱ sufferedȱ fromȱ lowȱ backȱ painȱ (LBP)ȱ inȱ relationȱ toȱ theirȱ pregnancy.ȱ Womenȱ whoȱ previouslyȱ hadȱ experiencedȱ ofȱ LBPȱ recurrentlyȱ statedȱ thatȱ theyȱ experiencedȱ aȱ “new”ȱ formȱ ofȱ LBPȱ whileȱ pregnant.ȱ Theȱ “new”ȱ LBPȱ wasȱ differentȱ inȱ termsȱ ofȱ locationȱ andȱ characterȱasȱwellȱasȱincludedȱnewȱsymptoms.ȱItȱcouldȱoccurȱinsteadȱofȱorȱinȱadditionȱtoȱ theȱ previouslyȱ experiencedȱ intermittentȱ LBP.ȱ Descriptionsȱ suchȱ asȱ “aȱ veryȱ strongȱ trainingȱ acheȱ thatȱ spread”,ȱ “Iȱ feelȱ likeȱ myȱ bodyȱ isȱ fallingȱ apart”,ȱ andȱ “myȱ hipȱ isȱ locking”ȱ wereȱ descriptionsȱ notȱ typicallyȱ heardȱ inȱ relationȱ toȱ nonpregnancyȬrelatedȱ LBP.ȱ
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LBPȱ inȱ pregnancyȱ isȱ sometimesȱ lookedȱ uponȱ asȱ aȱ normalȱ consequenceȱ ofȱ pregnancyȱ thatȱtheȱwomanȱmustȱendure.ȱTheȱquestionȱhasȱarisenȱasȱtoȱwhatȱimpactȱpregnancyȬ relatedȱLBPȱhasȱonȱdailyȱlife.ȱPreviousȱdescriptionsȱofȱtheȱimpactȱofȱpregnancyȬrelatedȱ LBPȱ onȱ functioningȱ haveȱ mostlyȱ beenȱ obtainedȱ fromȱ selfȬreportedȱ painȱ increasingȱ activitiesȱ orȱ sickȱ leaveȱ reports.ȱ Thereforeȱ itȱ isȱ difficultȱ toȱ compareȱ resultsȱ betweenȱ studiesȱandȱtoȱcompareȱwithȱstudiesȱonȱnonpregnancyȬrelatedȱLBP.ȱ
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Throughoutȱ theȱ years,ȱ oneȱ clinicalȱ opinionȱ hasȱ beenȱ thatȱ womenȱ withȱ pregnancyȬ relatedȱ LBPȱ areȱ womenȱ whoȱ areȱ lessȱ tolerantȱ toȱ pregnancy,ȱ eitherȱ physicallyȱ orȱ mentally.ȱTheȱquestionȱhasȱarisenȱasȱtoȱwhetherȱthereȱisȱaȱdifferenceȱinȱmuscleȱfunctionȱ inȱ womenȱ whoȱ haveȱ pregnancyȬrelatedȱ LBPȱ comparedȱ toȱ pregnantȱ womenȱ withoutȱ LBP.ȱAdditionally,ȱisȱthereȱanȱassociationȱbetweenȱpersistentȱLBPȱandȱmentalȱhealth,ȱ whichȱshouldȱbeȱconsideredȱbyȱtheȱcaregiverȱwhenȱplanningȱtheȱtreatmentȱstrategies?ȱ ȱ
Afterȱ delivery,ȱ theȱ majorityȱ ofȱ womenȱ reportȱ thatȱ theȱ “new”ȱ typeȱ ofȱ LBPȱ disappearsȱ whereasȱ theȱ “old”ȱ badȱ backȱ remains.ȱ Howeverȱ whatȱ happensȱ whenȱ theȱ “new”ȱ LBPȱ persistsȱbeyondȱdelivery?ȱFurthermore,ȱisȱitȱpossibleȱtoȱpredictȱearlyȱonȱwhoȱisȱatȱriskȱ forȱpersistentȱLBPȱpostpartum?ȱ
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BACKGROUNDȱ
TERMINOLOGYȱ
Painȱlocalisationȱisȱoneȱwayȱofȱclassifyingȱlowȱbackȱpainȱ(LBP).ȱLBPȱhasȱbeenȱ definedȱasȱpainȱlocatedȱbetweenȱtheȱtwelfthȱribȱandȱtheȱglutealȱfoldsȱ(89,ȱ242).ȱ Inȱthisȱthesisȱtheȱtermsȱlowȱbackȱpain,ȱpelvicȱgirdleȱpainȱandȱlumbarȱpainȱareȱ used.ȱ
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LowȱBackȱPainȱisȱconsideredȱasȱanȱumbrellaȱtermȱforȱpainȱlocalisedȱinȱtheȱpelvicȱ andȱ lumbarȱ regions.ȱ Theȱ numerousȱ termsȱ forȱ pregnancyȬrelatedȱ LBPȱ inȱ theȱ pelvisȱ(267)ȱreflectȱtheȱuncertaintyȱofȱtheȱetiologyȱandȱtoȱdate,ȱitȱisȱconsideredȱaȱ syndrome,ȱ i.e.ȱ aȱ groupȱ ofȱ signsȱ orȱ symptomsȱ whoseȱ appearanceȱ togetherȱ usuallyȱ indicatesȱ theȱ presenceȱ ofȱ aȱ particularȱ diseaseȱ orȱ disorderȱ (Chambersȱ Referenceȱ Online).ȱ Thereȱ existedȱ aȱ needȱ forȱ aȱ termȱ thatȱ describedȱ theȱ pregnancyȬrelatedȱ LBPȱ syndromeȱ andȱ includedȱ theȱ ligaments,ȱ jointȱ capsulesȱ andȱmusclesȱinȱtheȱpelvis,ȱasȱwellȱasȱtheȱsacroiliacȱjointȱ(SIJ)ȱandȱthatȱexcludedȱ gynecologicalȱ and/orȱ urologicalȱ disorders.ȱ Theȱ termȱ Pelvicȱ Girdleȱ Painȱ (PGP)ȱ wasȱproposed,ȱwithȱtheȱfollowingȱdefinition:ȱ“Pelvicȱgirdleȱpainȱ(PGP)ȱgenerallyȱ arisesȱ inȱ relationȱ toȱ pregnancy,ȱ traumaȱ orȱ reactiveȱ arthritis.ȱ Painȱ isȱ experiencedȱ betweenȱ theȱ posteriorȱ iliacȱ crestȱandȱ theȱglutealȱ fold,ȱparticularȱ inȱ theȱ vicinityȱ ofȱ theȱ sacroiliacȱjointsȱ(SIJ).ȱTheȱpainȱmayȱradiateȱinȱtheȱposteriorȱthighȱandȱcanȱalsoȱoccurȱ inȱ conjunctionȱ with/orȱ separatelyȱ inȱ theȱ symphysis.ȱ Theȱ enduranceȱ capacityȱ forȱ standing,ȱwalkingȱandȱsittingȱisȱdiminished.ȱTheȱdiagnosisȱofȱPGPȱcanȱbeȱreachedȱafterȱ exclusionȱ ofȱ lumbarȱ causes.ȱ Theȱ painȱ orȱ functionalȱ disturbancesȱ inȱ relationȱ toȱ PGPȱ mustȱbeȱreproducibleȱbyȱspecificȱclinicalȱtests.”(258).ȱ
Inȱthisȱthesis,ȱtheȱPGPȱthatȱarisesȱinȱrelationȱtoȱpregnancyȱisȱstudied.ȱ ȱ
Theȱ termȱ Lumbarȱ Painȱ isȱ usedȱ forȱ painȱ thatȱ isȱ ofȱ lumbarȱ originȱ (151),ȱ withȱ orȱ withoutȱradiationȱinȱtheȱleg,ȱandȱwithoutȱaȱspecificallyȱdefinedȱpainȱstructure.ȱ
EPIDEMIOLOGYȱ
Prevalenceȱofȱlowȱbackȱpainȱinȱwomenȱ
Inȱgeneral,ȱwomenȱreportȱmoreȱmusculoskeletalȱpainȱthanȱmenȱ(15,ȱ114,ȱ257).ȱ Amongȱ allȱ musculoskeletalȱ disorders,ȱ LBPȱ isȱ theȱ largestȱ entityȱ (195).ȱ Inȱ aȱ generalȱpopulation,ȱitȱhasȱbeenȱfoundȱthatȱ10Ȭ28%ȱofȱwomenȱrelateȱtheirȱdebutȱ ofȱLBPȱtoȱaȱpregnancyȱ(20,ȱ229).ȱ
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PregnancyȬrelatedȱbackȱpainȱhasȱbeenȱreportedȱfromȱallȱoverȱtheȱworldȱ(2,ȱ24,ȱ 55,ȱ 61,ȱ 72,ȱ 128,ȱ 137,ȱ 138,ȱ 150,ȱ 157,ȱ 169,ȱ 174,ȱ 185,ȱ 235,ȱ 236,ȱ 241,ȱ 245,ȱ 263).ȱ Theȱ incidenceȱ ofȱ backȱ painȱ inȱ pregnancyȱ isȱ rarelyȱ reported,ȱ andȱ theȱ 2ȱ studiesȱ identifiedȱshowedȱaȱlargeȱvariationȱ(27Ȭ61%)ȱ(116,ȱ177).ȱInȱaȱrecentȱreview,ȱtheȱ periodȱprevalenceȱofȱanyȱtypeȱofȱLBPȱwasȱestimatedȱtoȱ45%ȱ(rangeȱ3.9Ȭ89.9%)ȱ inȱ pregnancyȱ andȱ 25%ȱ (rangeȱ 0.3Ȭ67%)ȱ postpartumȱ (267).ȱ Althoughȱ notȱ directlyȱinȱassociationȱwithȱtheȱpregnancyȱterm,ȱaȱselfȬreportedȱ1Ȭyearȱperiodȱ prevalenceȱofȱLBPȱofȱ45Ȭ54%ȱwasȱfoundȱinȱgeneralȱNordicȱpopulationsȱofȱ30ȱtoȱ 50ȱ yearȱ oldȱ femalesȱ (126).ȱ Theȱ pointȱ prevalenceȱ ofȱ LBPȱ inȱ theȱ femaleȱ reproductiveȱ yearsȱ hasȱ beenȱ selfȬreportedȱ asȱ 26%ȱ inȱ theȱ 25Ȭ44ȱ yearȱ ageȱ bandȱ (195),ȱandȱ20%ȱinȱtheȱ16Ȭ44ȱyearȱageȱbandȱ(237).ȱTheȱpointȱprevalenceȱofȱLBPȱinȱ pregnantȱ womenȱ isȱ increasedȱ (rangeȱ 22Ȭ63.4%)ȱ comparedȱ toȱ womenȱ ofȱ theȱ sameȱmeanȱageȱ(6.3%)ȱinȱaȱgeneralȱpopulationȱ(19,ȱ116,ȱ177).ȱSixteenȱpercentȱofȱ womenȱ withȱ pregnancyȬrelatedȱ LBPȱ reportedȱ persistentȱ painȱ 6ȱ yearsȱ afterȱ childbirthȱ(182).ȱPregnancyȱisȱtherebyȱaȱspecificȱsituationȱthatȱincreasesȱtheȱriskȱ ofȱLBP,ȱasȱwellȱasȱtheȱriskȱofȱpersistentȱLBP.ȱ
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Theȱ prevalenceȱ ofȱ LBPȱ inȱ pregnancyȱ andȱ postpartumȱ isȱ mostlyȱ basedȱ uponȱ selfȬreportsȱthroughȱquestionnairesȱorȱinterviewsȱ(24,ȱ61,ȱ66,ȱ128,ȱ138,ȱ154,ȱ169,ȱ 176,ȱ 177,ȱ 185,ȱ 211,ȱ 235,ȱ 236)ȱ andȱ rarelyȱ confirmedȱ andȱ classifiedȱ withȱ clinicalȱ evaluationȱ (3,ȱ 14,ȱ 116,ȱ 121,ȱ 183).ȱ Differencesȱ inȱ terminology,ȱ methodology,ȱ includingȱ differentȱ classificationȱ criteriaȱ forȱ theȱ studiedȱ syndrome,ȱ andȱ theȱ samplesȱ underȱ study,ȱ e.g.ȱ onlyȱ thoseȱ withȱ painȱ warrantingȱ medicalȱ help,ȱ areȱ plausibleȱcausesȱforȱtheȱwideȱrangeȱinȱreportedȱprevalence.ȱ
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Inȱaȱfewȱstudies,ȱPGPȱwasȱclinicallyȱdifferentiatedȱfromȱpainȱofȱlumbarȱorigin.ȱ TheȱreportedȱprevalenceȱofȱPGPȱduringȱpregnancyȱwasȱfoundȱtoȱbeȱ14Ȭ28%ȱ(2,ȱ 121,ȱ 157)ȱ andȱ 4Ȭ5%ȱ 2Ȭ3ȱ monthsȱ postpartum.ȱ Theȱ prevalenceȱ ofȱ lowerȱ lumbarȱ painȱinȱpregnancyȱwasȱreportedȱasȱ6.5%ȱbyȱAlbertȱetȱal.ȱ(2000)ȱ(2)ȱandȱasȱ13.2%ȱ
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byȱMousaviȱetȱal.ȱ(2007)ȱ(157),ȱhoweverȱtheȱpostpartumȱprevalenceȱofȱlumbarȱ painȱisȱunknown.ȱ
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ItȱisȱcomplicatedȱtoȱcompareȱtheȱprevalenceȱofȱpregnancyȬrelatedȱLBPȱwithȱtheȱ epidemiologyȱ ofȱ LBPȱ inȱ generalȱ populations.ȱ Besidesȱ methodologicalȱ differences,ȱ generalȱ populationsȱ usuallyȱ haveȱ broaderȱ ageȱ ranges,ȱ olderȱ ageȱ bands,ȱLBPȱofȱlongerȱduration,ȱandȱareȱnotȱgenderȱdifferentiated.ȱHowever,ȱitȱ doesȱ appearȱ thatȱ theȱ 9Ȭmonthȱ prevalence,ȱ asȱ wellȱ asȱ theȱ pointȱ prevalenceȱ ofȱ LBPȱinȱaȱpregnancyȱisȱhigherȱcomparedȱtoȱwomenȱofȱtheȱsameȱageȱinȱaȱgeneralȱ population.ȱ
Courseȱandȱpredictorsȱofȱlowȱbackȱpainȱ
Moreȱ thanȱ 70%ȱ ofȱ theȱ industrializedȱ populationȱ hasȱ LBPȱ sometimeȱ duringȱ theirȱ lifetime.ȱ Amongȱ patientsȱ withȱ acuteȱ LBP,ȱ 76Ȭ90%ȱ improvedȱ withinȱ 1ȱ monthȱ (8,ȱ 44,ȱ 79),ȱ regardlessȱ ofȱ theȱ typeȱ ofȱ treatmentȱ receivedȱ (99).ȱ Howeverȱ theseȱnumbersȱdoȱnotȱreferȱtoȱcompleteȱrecovery.ȱTheȱmajorityȱcontinueȱtoȱbeȱ symptomaticȱafterȱ1ȱyear,ȱwithȱonlyȱ21%ȱhavingȱrecoveredȱwithȱregardȱtoȱpainȱ andȱ25%ȱwithȱregardȱtoȱdisabilityȱ(48).ȱWithinȱaȱyear,ȱrelapsesȱareȱseenȱinȱ60%ȱ (rangeȱ 44Ȭ78%)ȱ ofȱ theȱ patientsȱ (89).ȱ Nonspecificȱ LBPȱ isȱ increasinglyȱ regardedȱ asȱhavingȱaȱpersistent,ȱfluctuatingȱsymptomȱcourseȱwithȱintermittentȱflaresȱ(48,ȱ 262).ȱ
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MostȱwomenȱrecoverȱfromȱpregnancyȬrelatedȱLBP,ȱalthoughȱtheȱriskȱofȱLBPȱinȱ aȱsubsequentȱpregnancyȱisȱhighȱ(36).ȱImprovementȱisȱapparentȱuntilȱaboutȱ3Ȭ6ȱ monthsȱpostpartumȱ(112,ȱ176,ȱ182).ȱForȱthoseȱwomenȱwithȱpersistentȱpainȱatȱ3ȱ monthsȱpostpartum,ȱtheȱriskȱofȱlongȬtermȱproblemsȱisȱgreatȱ(176,ȱ182),ȱwhichȱisȱ similarȱ toȱ nonpregnancyȬrelatedȱ LBPȱ ofȱ durationȱ longerȱ thanȱ 3ȱ monthsȱ (89).ȱ Theȱ timeȱ pointȱ mayȱ haveȱ anȱ associationȱ withȱ theȱ earlyȱ findingsȱ ofȱ theȱ remissionȱ ofȱ jointȱ relaxation,ȱ whichȱ terminatesȱ 6ȱ monthsȱ postpartumȱ atȱ theȱ latestȱ(90).ȱInȱaȱ12ȬyearȱfollowȬupȱstudyȱofȱwomenȱwithȱLBPȱsevereȱenoughȱtoȱ requireȱ sickȱ leaveȱ whileȱ pregnant,ȱ 92%ȱ reportedȱ LBPȱ duringȱ aȱ subsequentȱ pregnancyȱandȱ86%ȱhadȱrecurrentȱLBPȱwhileȱnotȱpregnantȱ(36).ȱ
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Oneȱ ofȱ theȱ mostȱ frequentlyȱ reportedȱ predictorsȱ forȱ eitherȱ developingȱ LBPȱ duringȱ pregnancyȱ orȱ havingȱ persistentȱ LBPȱ postpartumȱ isȱ theȱ previousȱ experienceȱ ofȱ LBP,ȱ eitherȱ inȱ anȱ earlierȱ pregnancyȱ orȱ outsideȱ theȱ pregnancyȱ (11).ȱ Reportedȱ premorbidȱ riskȱ factorsȱ areȱ traumaȱ ofȱ theȱ backȱ orȱ pelvis,ȱ (5),ȱ previousȱ lowerȱ abdominalȱ painȱ (121),ȱ andȱ multiparityȱ (5,ȱ 177).ȱ Aȱ greaterȱ
numberȱ ofȱ yearsȱ ofȱ previousȱ regularȱ leisureȱ physicalȱ activityȱ decreasedȱ theȱ riskȱ ofȱ developingȱ pregnancyȬrelatedȱ LBPȱ (153).ȱ Reportedȱ episodeȬrelatedȱ factorsȱ forȱ LBPȱ inȱ pregnancyȱ areȱ lackȱ ofȱ exerciseȱ (121),ȱ youngerȱ ageȱ (177),ȱ higherȱ levelsȱ ofȱ stress,ȱ workȱ dissatisfactionȱ (5),ȱ uncomfortableȱ workingȱ conditionsȱ (121,ȱ177),ȱ occupationsȱ describedȱ asȱ mainlyȱ physicallyȱdemandingȱ (153),ȱandȱhigherȱBMIȱ(116).ȱ
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EpisodeȬrelatedȱ factorsȱ associatedȱ withȱ persistentȱ LBPȱ andȱ PGPȱ includeȱ featuresȱ specificȱ toȱ theȱ painȱ episodeȱ (severityȱ ofȱ complaints,ȱ earlierȱ onsetȱ ofȱ pain,ȱ highȱ painȱ intensity,ȱ andȱ walkingȱ deficiency),ȱ andȱ maternalȱ factorsȱ (higherȱ BMI,ȱ age,ȱ andȱ jointȱ hypermobility)(11,ȱ 154,ȱ 211).ȱ Lumbarȱ painȱ hasȱ shownȱ aȱ strongerȱ associationȱ toȱ preȬpregnancyȱ LBPȱ (14,ȱ 183),ȱ whileȱ PGPȱ isȱ moreȱ closelyȱ relatedȱ toȱ aȱ pregnancyȱ inȱ occurrenceȱ andȱ recurrence.ȱ Theȱ selfȬ reportedȱ predictorsȱ andȱ courseȱ ofȱ pregnancyȬrelatedȱ LBPȱ postpartumȱ areȱ partlyȱ known,ȱ butȱ notȱ forȱ clinicallyȱ classifiedȱ subgroupsȱ ofȱ patientsȱ withȱ pregnancyȬrelatedȱ LBP.ȱ Thusȱ itȱ isȱ notȱ knownȱ whetherȱ orȱ notȱ aȱ specificȱ subgroupȱ ofȱ patientsȱ withȱ pregnancyȬrelatedȱ LBPȱ hasȱ anȱ increasedȱ riskȱ forȱ persistency.ȱ
PREGNANCYȬRELATEDȱPELVICȱGIRDLEȱPAINȱANDȱ LUMBARȱPAINȱ
SeveralȱauthorsȱhaveȱidentifiedȱPGPȱandȱlumbarȱpainȱasȱ2ȱmajorȱsubtypesȱofȱ painȱinȱtheȱlowerȱpartȱofȱtheȱspineȱandȱinȱtheȱpelvisȱduringȱpregnancyȱ(38,ȱ40,ȱ 61,ȱ 116,ȱ 157,ȱ 183,ȱ 189,ȱ 228,ȱ 238).ȱ Womenȱ withȱ PGPȱ haveȱ aȱ differentȱ clinicalȱ presentationȱ thanȱ womenȱ withȱ lumbarȱ painȱ (Tableȱ 1)(183,ȱ 228).ȱ Clinicalȱ experience,ȱasȱwellȱasȱpreviousȱresearch,ȱsuggestȱdifferentȱtreatmentȱstrategiesȱ forȱPGPȱandȱlumbarȱpainȱinȱrelationȱtoȱpregnancyȱ(183,ȱ189).ȱItȱhasȱbeenȱstatedȱ thatȱPGPȱcanȱworsenȱifȱtreatedȱasȱgeneralȱnonpregnancyȬrelatedȱLBPȱ(183).ȱItȱ hasȱ furtherȱ beenȱ reportedȱ thatȱ PGPȱ andȱ PGPȱ combinedȱ withȱ lumbarȱ painȱ (combinedȱpain)ȱhaveȱaȱgreaterȱimpactȱonȱdailyȱactivityȱsuchȱasȱwalkingȱandȱ houseworkȱthanȱlumbarȱpainȱaloneȱ3ȱyearsȱafterȱpregnancyȱ(168).ȱ
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Tableȱ1.ȱCharacteristicȱfeaturesȱofȱpregnancyȬrelatedȱPelvicȱGirdleȱPainȱandȱLumbarȱPainȱ fromȱclinicalȱexperience.ȱ
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Featuresȱ PelvicȱGirdleȱPainȱ LumbarȱPainȱ
Painȱ Locationȱ
Deepȱuni/bilateralȱpainȱinȱbuttocksȱbetweenȱiliacȱcrestȱandȱ glutealȱfold,ȱdistalȱtoȱlumbarȱspineȱorȱinȱtheȱsymphysis.ȱ Mayȱradiateȱtoȱposterolateralȱthigh,ȱtoȱknee,ȱrarelyȱtoȱcalf,ȱ neverȱtoȱfoot.ȱ
Painȱoriginȱinȱandȱbesideȱtheȱ lumbarȱspine,ȱwithȱorȱwithoutȱ radiationȱtoȱlegȱorȱfoot.ȱ Functionalȱ
Limitationsȱ
Prolongedȱpositionsȱorȱactivities,ȱaboveȱallȱsitting,ȱ standing,ȱwalking.ȱActivitiesȱinvolvingȱabductionȬexternalȱ rotationȱofȱhipȱorȱasymmetricalȱloadingȱofȱtheȱpelvisȱ
Someȱpositionsȱorȱactivitiesȱ decreaseȱpain;ȱothersȱincrease.ȱ Clinicalȱ
Featuresȱ
Catchingȱofȱtheȱleg*.ȱDelayȱinȱpainȱresponse.ȱPainȱdebutȱinȱ relationȱtoȱpregnancy.ȱNoȱpositiveȱnerveȱrootȱtest.ȱ
Restrictedȱspinalȱrangeȱofȱ motion.ȱRecurrentȱpainȱ episodesȱbeforeȱpregnancy.ȱ Mayȱhaveȱpositiveȱnerveȱrootȱ test.ȱȱ
*Catchingȱofȱtheȱleg:ȱdifficultyȱinȱmovingȱoneȱorȱbothȱlegsȱforwardȱwhenȱwalkingȱ(228).ȱ
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Mostȱ studiesȱ doȱ notȱ differentiateȱ betweenȱ PGPȱ andȱ lumbarȱ pain,ȱ neitherȱ duringȱpregnancyȱnorȱpostpartumȱ(12,ȱ66,ȱ128,ȱ138,ȱ154,ȱ169,ȱ174,ȱ176,ȱ182,ȱ185,ȱ 235,ȱ 236,ȱ 263),ȱ orȱ excludeȱ womenȱ withȱ lumbarȱ painȱ (3,ȱ 121,ȱ 165).ȱ However,ȱ clinicalȱ classificationȱ isȱ importantȱ inȱ orderȱ toȱ evaluateȱ possibleȱ differencesȱ inȱ subgroupȱ prevalence,ȱ course,ȱ cause,ȱ consequences,ȱ andȱ predictorsȱ ofȱ persistency,ȱandȱtherebyȱpossibleȱdifferencesȱinȱmanagement.ȱPregnancyȱitselfȱ mayȱ interfereȱ withȱ studiedȱ factors.ȱ Thereforeȱ itȱ isȱ importantȱ toȱ followȱ allȱ pregnantȱ womenȱ ofȱ aȱ cohort,ȱ includingȱ womenȱ withȱ allȱ typesȱ ofȱ nonspecificȱ LBP,ȱasȱwellȱasȱwomenȱwithoutȱLBP.ȱ
Classificationȱofȱlowȱbackȱpainȱ
Healthcareȱ planningȱ andȱ clinicalȱ professionalsȱ needȱ informationȱ sufficientȱ enoughȱ toȱ decideȱ onȱ theȱ choiceȱ ofȱ treatmentȱ andȱ preventiveȱ measures.ȱ Theȱ goalȱ ofȱ classificationȱ isȱ toȱ haveȱ aȱ diagnosisȱ thatȱmayȱ explainȱ theȱ causeȱ ofȱ theȱ syndrome/disease,ȱgiveȱaȱprognosis,ȱassistȱinȱtheȱchoiceȱofȱtherapy,ȱandȱpredictȱ theȱoutcomeȱofȱaȱspecificȱtherapy.ȱ
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Theȱ onlyȱ acceptedȱ classificationȱ ofȱ nonspecificȱ LBPȱ isȱ theȱ durationȱ ofȱ pain.ȱ AcuteȱLBPȱisȱwhenȱtheȱdurationȱisȱlessȱthanȱ6ȱweeks,ȱsubacuteȱLBPȱisȱwhenȱtheȱ painȱ durationȱ isȱ 6Ȭ12ȱ weeks,ȱ andȱ persistentȱ LBPȱ isȱ classifiedȱ whenȱ painȱ durationȱ isȱ moreȱ thanȱ 12ȱ weeksȱ (242).ȱ Thisȱ classificationȱ isȱ notȱ enoughȱ forȱ guidingȱ managementȱ andȱ itȱ mayȱ notȱ beȱ relevantȱ forȱ classificationȱ ofȱ LBPȱ inȱ pregnancy.ȱ Anotherȱ wayȱ toȱ classifyȱ LBPȱ isȱ accordingȱ toȱ theȱ severityȱ ofȱ theȱ complaintsȱthatȱmayȱbeȱofȱimportanceȱforȱunderstandingȱtheȱcourseȱ(58).ȱThisȱ
appearsȱ toȱ beȱ anȱ importantȱ classification,ȱ butȱ fromȱ aȱ clinicalȱ perspective,ȱ itȱ shouldȱbeȱmadeȱwithinȱtheȱsubgroupsȱofȱpatientsȱwithȱLBP.ȱ
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Thereȱ isȱ noȱ anatomicallyȬspecificȱ diagnosticȱ toolȱ forȱ possibleȱ painȱ sourcesȱ ofȱ PGP.ȱ Additionally,ȱ noȱ objectiveȱ findingsȱ forȱ PGPȱ onȱ XȬray,ȱ MRI,ȱ orȱ inȱ bloodȱ samplesȱhaveȱbeenȱidentifiedȱ(84).ȱFromȱaȱclinicalȱpointȱofȱview,ȱaȱdiagnosticȱ triageȱ thatȱ differentiatesȱ betweenȱ seriousȱ pathologyȱ (redȱ flags),ȱ nerveȱ rootȱ problems,ȱ andȱ nonspecificȱ LBPȱ isȱ theȱ firstȱ stepȱ toȱ takeȱ forȱ patientsȱ withȱ LBPȱ (111,ȱ 242).ȱ Theȱ majorityȱ ofȱ patientsȱ withȱ LBPȱ fallȱ intoȱ theȱ categoryȱ ofȱ nonspecificȱ LBPȱ andȱ aȱ furtherȱ classificationȱ isȱ neededȱ inȱ orderȱ toȱ chooseȱ treatmentȱ strategies.ȱ Thisȱ classificationȱ doesȱ notȱ necessarilyȱ needȱ toȱ includeȱ explanationȱofȱtheȱcause.ȱ
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Basedȱ onȱ currentȱ knowledgeȱ andȱ existingȱ guidelinesȱ forȱ PGPȱ (258)ȱ andȱ LBPȱ (242),ȱclinicalȱevaluationȱofȱpregnancyȬrelatedȱLBPȱshouldȱincludeȱpelvicȱpainȱ provocationȱ tests,ȱ aȱ neurologicalȱ examination,ȱ takeȱ knownȱ characteristicsȱ ofȱ PGPȱ andȱ lumbarȱ painȱ intoȱ account,ȱ andȱ beȱ sufficientȱ enoughȱ toȱ identifyȱ discogenicȱpainȱandȱredȱflagȱconditions.ȱ
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Manyȱ differentȱ pelvicȱ painȱ provocationȱ testsȱ andȱ criteriaȱ haveȱ beenȱ usedȱ forȱ classifyingȱ PGPȱ (2,ȱ 14,ȱ 115,ȱ 164,ȱ 165,ȱ 180,ȱ 181,ȱ 226,ȱ 228,ȱ 264).ȱ Noȱ conclusionsȱ canȱ beȱ drawnȱ asȱ toȱ whichȱ criteriaȱ orȱ clinicalȱ testsȱ shouldȱ beȱ usedȱ forȱ PGP.ȱ Regardingȱcriteriaȱforȱtheȱ numberȱofȱpositiveȱpelvicȱpainȱprovocationȱtests,ȱ1ȱ (2,ȱ 183),ȱ 2ȱ (164,ȱ 264),ȱ andȱ 3ȱ (165)ȱ positiveȱ pelvicȱ painȱ provocationȱ testsȱ haveȱ beenȱ suggestedȱ orȱ usedȱ asȱ diagnosticȱ criteriaȱ forȱ PGP.ȱ Inȱ anotherȱ study,ȱ theȱ bestȱ discriminatoryȱ abilityȱ wasȱ achievedȱ byȱ theȱ combinationȱ ofȱ 5ȱ painȱ provocationȱtests,ȱwhichȱwasȱreportedȱtoȱhaveȱaȱsensitivityȱofȱ67%,ȱspecificityȱ ofȱ84%,ȱandȱpredictiveȱvalueȱofȱ57%ȱwhenȱidentifyingȱwomenȱwithȱLBPȱinȱtheȱ lumbosacralȱ regionȱ (115).ȱ Furthermore,ȱ itȱ wasȱ shownȱ thatȱ pregnantȱ womenȱ withoutȱ PGPȱ mostlyȱ hadȱ negativeȱ painȱ provocationȱ testsȱ (0Ȭ15%)ȱ despiteȱ ligamentȱ laxityȱ dueȱ toȱ theȱ pregnancy.ȱ Despiteȱ noȱ LBPȱ thereȱ wasȱ palpableȱ tendernessȱ overȱ theȱ symphysisȱ inȱ 35%ȱ ofȱ theȱ womenȱ whichȱ makesȱ theȱ testȱ questionable.ȱ
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Classificationȱ ofȱ PGPȱ requiresȱ exclusionȱ ofȱ lumbarȱ causesȱ (258).ȱ Severalȱ testsȱ forȱ examinationȱ ofȱ theȱ lumbarȱ spineȱ inȱ pregnancyȱ haveȱ beenȱ describedȱ (115,ȱ 183,ȱ228).ȱHoweverȱtheȱtestȱreactionȱinȱtermsȱofȱpainȱorȱstiffnessȱisȱnotȱspecificȱ enoughȱ toȱ excludeȱ intervertebralȱ discȱ pathology,ȱ whichȱ isȱ probablyȱ theȱ mostȱ commonȱstructuralȱsourceȱofȱnonspecificȱLBPȱ(26,ȱ215).ȱThereȱisȱnoȱdifferenceȱ
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inȱ discȱ abnormalityȱ prevalenceȱ betweenȱ pregnantȱ andȱ nonpregnantȱ populationsȱ(250).ȱItȱisȱthereforeȱimportantȱtoȱalsoȱexamineȱpossibleȱdiscogenicȱ problemsȱinȱaȱpregnantȱpopulationȱwithȱLBP.ȱ
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Manyȱ classificationȱ systemsȱ existȱ forȱ patientsȱ withȱ LBP;ȱ theȱ strengthsȱ andȱ weaknessesȱhaveȱbeenȱdiscussedȱinȱreviewsȱ(22,ȱ192,ȱ205).ȱSeveralȱclassificationȱ systemsȱ forȱ LBPȱ patientsȱ haveȱ beenȱ identified,ȱ whichȱ areȱ relevantȱ forȱ physiotherapistsȱ(53,ȱ69,ȱ142,ȱ191,ȱ218).ȱTheȱMechanicalȱDiagnosisȱandȱTherapyȱ (MDT)(142)ȱhasȱbeenȱidentifiedȱasȱaȱwellȱdescribedȱclassificationȱsystem.ȱItȱisȱ commonlyȱ usedȱ (13,ȱ 77)ȱ andȱ includesȱ aȱ standardisedȱ history,ȱ neurologicalȱ examination,ȱ andȱ evaluationȱ ofȱ redȱ flags.ȱ Withinȱ theȱ protocol,ȱ symptomȱ responseȱ duringȱ andȱ afterȱ repeatedȱ movementsȱ isȱ evaluated,ȱ andȱ thisȱ procedureȱhasȱshownȱpromisingȱresultsȱinȱreliabilityȱstudiesȱ(110,ȱ141,ȱ201).ȱIf,ȱ asȱ aȱ resultȱ ofȱ repeatedȱ movementsȱ orȱ positions,ȱ theȱ radiatingȱ symptomsȱ regressȱ proximallyȱ (centralisation)ȱ orȱ theȱ opposite,ȱ progressȱ distallyȱ (peripheralisation),ȱtheȱsymptomsȱareȱconsideredȱdiscogenicȱandȱhaveȱshownȱ aȱ highȱ prognosticȱ valueȱ (56,ȱ 57,ȱ 252).ȱ Furthermore,ȱ pelvicȱ painȱ provocationȱ testsȱ wereȱ evaluatedȱ withinȱ theȱ MDTȱ protocol,ȱ withȱ aȱ reportedȱ sensitivityȱ toȱ detectȱ SIJȱ syndromeȱ ofȱ 0.91ȱ andȱ specificityȱ ofȱ 0.83ȱ (124).ȱ Itȱ wasȱ arguedȱ thatȱ positiveȱSIJȱtests,ȱinȱtheȱabsenceȱofȱcentralisation,ȱareȱsaferȱinȱdiagnosticȱtriageȱ thanȱpelvicȱpainȱprovocationȱtestsȱalone.ȱ
CAUSESȱOFȱPREGNANCYȬRELATEDȱPELVICȱGIRDLEȱPAINȱ
DiscussedȱcausesȱofȱpregnancyȬrelatedȱLBPȱinȱtheȱpelvisȱareȱmainlyȱbasedȱonȱ biomechanicalȱandȱhormonalȱchangesȱduringȱpregnancy.ȱHippocratesȱ(cȱ460Ȭcȱ 377ȱBC)ȱhadȱalreadyȱhypothesisedȱthatȱanȱirreversibleȱrelaxationȱofȱtheȱpelvisȱ occursȱ duringȱ pregnancy.ȱ Radiologicalȱ studiesȱ inȱ theȱ earlyȱ 20thȱ centuryȱ confirmedȱ relaxationȱ ofȱ theȱ pelvicȱ joints,ȱ andȱ showedȱ thatȱ itȱ wasȱ dependentȱ uponȱnormalȱbiologicalȱprocessesȱthatȱbeganȱinȱtheȱearlyȱstagesȱofȱpregnancyȱ (90,ȱ268).ȱTowardsȱtheȱendȱofȱtheȱ1920s,ȱitȱbecameȱmethodologicallyȱpossibleȱtoȱ studyȱtheȱroleȱhormonesȱplayedȱwithȱregardȱtoȱincreasedȱmobility.ȱRelaxinȱisȱ oneȱ pregnancyȬrelatedȱ hormoneȱ studied,ȱ consideredȱ toȱ playȱ aȱ roleȱ inȱ theȱ mobilityȱ ofȱ theȱ pelvicȱ joints.ȱ Theȱ hypothesisȱ thatȱ aȱ highȱ levelȱ ofȱ relaxinȱ correlatesȱwithȱPGPȱhasȱbeenȱconfirmedȱinȱsomeȱstudiesȱ(117,ȱ135),ȱbutȱnotȱinȱ othersȱ(4,ȱ190).ȱ
ȱ
Theȱ earlyȱ reportsȱ ofȱ increasedȱ mobilityȱ inȱ theȱ symphysis,ȱ asȱ wellȱ asȱ inȱ theȱ posteriorȱ pelvicȱ joints,ȱ areȱ probablyȱ theȱ basisȱ forȱ theȱ hypothesisȱ thatȱ PGPȱ isȱ
mainlyȱdueȱtoȱhypermobility.ȱYet,ȱinȱtheȱmidȬ1990s,ȱatȱtheȱtimeȱofȱtheȱplanningȱ ofȱ theȱ presentȱ thesis,ȱ thisȱ wasȱ anȱ establishedȱ beliefȱ amongȱ caregivers.ȱ However,ȱ itȱ hadȱ alreadyȱ beenȱ shownȱ withȱ roentgenȱ stereophotogrammetryȱ thatȱ theȱ quantityȱ ofȱ SIJȱ mobilityȱ wasȱ theȱ sameȱ inȱ womenȱ withȱ andȱ withoutȱ PGPȱ (227).ȱ Aȱ pregnancyȬinducedȱ physiologicalȱ increaseȱ inȱ laxityȱ ofȱ theȱ symphysealȱ softȱ tissueȱ hadȱ beenȱ reported.ȱ However,ȱ noȱ evidenceȱ wasȱ foundȱ thatȱ theȱ degreeȱ ofȱ symphysealȱ distensionȱ determinesȱ theȱ severityȱ ofȱ pelvicȱ painȱinȱpregnancyȱorȱpostpartumȱ(25).ȱItȱhasȱbeenȱsuggestedȱthatȱasymmetricȱ laxityȱofȱtheȱrightȱandȱleftȱSIJȱduringȱpregnancyȱisȱaȱpredictorȱforȱpersistenceȱofȱ moderateȬtoȬsevereȱpregnancyȬrelatedȱPGPȱpostpartumȱ(51).ȱ
Muscleȱfunctionȱinȱrelationȱtoȱlumbopelvicȱstabilityȱ
Onlyȱ inȱ moreȱ recentȱ yearsȱ hasȱ theȱ contributionȱ ofȱ muscleȱ functionȱ towardsȱ lumbopelvicȱ stabilityȱ beenȱ discussed.ȱ Accordingȱ toȱ Bastiaanssenȱ etȱ al.ȱ (2005)ȱ (11)ȱLehmannȱetȱal.ȱ(1861)ȱandȱSnellingȱetȱal.ȱ(1870)ȱwereȱtheȱfirstȱtoȱmentionȱ thatȱ greatȱ physicalȱ and/orȱ muscularȱ weaknessȱ wereȱ causesȱ ofȱ theȱ painfulȱ
“sensations”ȱ inȱ theȱ pelvis.ȱ Overȱ theȱ 100ȱ yearsȱ followingȱ theseȱ earlyȱ studies,ȱ veryȱfewȱauthorsȱhaveȱdiscussedȱtheȱimportanceȱofȱmuscles.ȱ“ReȬeducation”ȱofȱ theȱ backȱ muscles,ȱ afterȱ daysȱ ofȱ treatmentȱ withȱ completeȱ bedȱ rest,ȱ hasȱ brieflyȱ beenȱ mentionedȱ (268).ȱ Genellȱ (1949)ȱ discussedȱ theȱ causeȱ ofȱ aȱ positiveȱ Trendelenburg’sȱ testȱ inȱ severeȱ casesȱ andȱ consideredȱ looseningȱ ofȱ theȱ SIJȱ andȱ symphysisȱ toȱ beȱ soȱ extremeȱ thatȱ theȱ musclesȱ couldȱ notȱ holdȱ upȱ theȱ nonsupportedȱhalfȱofȱtheȱpelvisȱ(75).ȱFarbrotȱ(1952)ȱdiscussedȱtheȱimportanceȱ ofȱ theȱ longȱ hipȱ extensorsȱ andȱ theȱ abdominalȱ musclesȱ whichȱ preventȱ aȱ horizontalȱpositionȱofȱtheȱsacrumȱ(65).ȱLikewise,ȱtheȱwastingȱofȱtheȱabdominalȱ wallȱ musclesȱ wasȱ mentionedȱ asȱ aȱ probableȱ causeȱ ofȱ PGP.ȱ Furthermore,ȱ theȱ valueȱ ofȱ “systematicȱ exercise”ȱ wasȱ discussedȱ asȱ aȱ prophylacticȱ measure.ȱ Inȱ anotherȱ study,ȱ itȱ wasȱ statedȱ thatȱ “aȱ moreȱ orȱ lessȱ functionalȱ insufficiencyȱ ofȱ musculatureȱofȱtheȱpelvicȱgirdleȱhasȱitsȱplaceȱinȱtheȱsymptomatology”ȱ(238).ȱ ȱ
Theȱ lumbopelvicȱ regionȱ needsȱ toȱ beȱ stableȱ inȱ orderȱ toȱ permitȱ loadȱ transferȱ fromȱ theȱ trunkȱ toȱ theȱ lowerȱ extremities.ȱ Atȱ theȱ sameȱ time,ȱ thereȱ mustȱ beȱ aȱ certainȱamountȱofȱmobilityȱinȱorderȱtoȱachieveȱlocomotion.ȱStaticȱandȱdynamicȱ stabilityȱ areȱ achievedȱ whenȱ theȱ active,ȱ passiveȱ andȱ controlȱ systemsȱ workȱ togetherȱ (188).ȱ Aȱ biomechanicalȱ modelȱ ofȱ aȱ selfȬlockingȱ mechanismȱ ofȱ theȱ pelvicȱ joints,ȱ basedȱ onȱ theȱ principlesȱ ofȱ formȱ andȱ forceȱ closure,ȱ hasȱ beenȱ describedȱ (221,ȱ 260).ȱ Formȱ closureȱ refersȱ toȱ theȱ closelyȱ fittingȱ sacroiliacȱ jointȱ surfaces.ȱForceȱclosureȱrefersȱtoȱtheȱcompressiveȱforcesȱneededȱinȱadditionȱtoȱ
ȱ
theȱ formȱ closureȱ inȱ orderȱ toȱ withstandȱ theȱ verticalȱ loadȱ onȱ theȱ relativelyȱ flatȱ surfacesȱofȱtheȱSIJ.ȱTheȱmusculoligamentousȱsystem,ȱgovernedȱbyȱtheȱnervousȱ system,ȱ isȱ responsibleȱ forȱ forceȱ closure.ȱ Theȱ musclesȱ mayȱ beȱ dividedȱ intoȱ 2ȱ functionalȱ muscleȱ systems:ȱ aȱ deep/localȱ andȱ aȱ superficial/globalȱ systemȱ (16).ȱ Theȱ localȱ musclesȱ areȱ thoughtȱ toȱ provideȱ controlȱ andȱ fineȬtuningȱ ofȱ intersegmentalȱmotionȱthatȱisȱnotȱspecificȱtoȱtheȱdirectionȱofȱforceȱwhereasȱtheȱ globalȱmusclesȱcontrolȱtheȱorientationȱofȱtheȱspineȱandȱdirectȱmovements.ȱTheȱ conceptȱofȱmotorȱcontrol,ȱwhereȱtheȱdeepȱmuscleȱcorsetȱandȱtheȱglobalȱmusclesȱ workȱinȱconcert,ȱdetermineȱtheȱlumbopelvicȱstabilityȱ(92,ȱ203,ȱ220).ȱ
ȱ
Severalȱ studiesȱ suggestȱ anȱ associationȱ betweenȱ nonpregnancyȬrelatedȱ PGPȱ andȱ decreasedȱ stabilityȱ ofȱ theȱ pelvis,ȱ probablyȱ dueȱ toȱ dysfunctionȱ ofȱ theȱ musclesȱwhichȱcontributeȱtoȱforceȱclosureȱofȱtheȱpelvicȱjointsȱ(96,ȱ184,ȱ198,ȱ204,ȱ 243).ȱ Whenȱ theȱ muscularȱ capacityȱ andȱ theȱ tensionȱ ofȱ theȱ ligamentsȱ areȱ inadequate,ȱ decreasedȱ compressionȱ acrossȱ theȱ SIJȱ willȱ occur,ȱ insufficientȱ stabilityȱ willȱ follow,ȱ andȱ optimalȱ loadȱ transferȱ betweenȱ theȱ backȱ andȱ legsȱ becomesȱcompromisedȱ(198).ȱȱ
ȱ
Theȱerectorȱspinae,ȱtheȱbicepsȱfemorisȱandȱtheȱgluteusȱmaximusȱareȱimportantȱ musclesȱforȱforceȱclosureȱofȱtheȱSIJȱ(243,ȱ259).ȱOtherȱmusclesȱofȱimportanceȱinȱ stabilizationȱofȱtheȱlumbopelvicȱareaȱareȱtheȱtransverseȱabdominalsȱ(204)ȱandȱ theȱ pelvicȱ floorȱ musclesȱ (212).ȱ Strengthȱ andȱ enduranceȱ ofȱ musclesȱ inȱ theȱ lumbopelvicȱ areaȱ haveȱ notȱ beenȱ testedȱ inȱ pregnantȱ women.ȱ However,ȱ itȱ hasȱ beenȱ reportedȱ that,ȱ comparedȱ toȱ healthyȱ controls,ȱ patientsȱ withȱ LBPȱ haveȱ lowerȱenduranceȱinȱtheȱbackȱextensorsȱ(1,ȱ95)ȱandȱhipȱextensorsȱ(middleȬagedȱ women)ȱ(106),ȱdeficiencyȱinȱtrunkȱmusclesȱstrengthȱ(233),ȱandȱpoorerȱabilityȱtoȱ senseȱaȱchangeȱinȱlumbarȱposition,ȱespeciallyȱafterȱfatigueȱ(232).ȱ
ȱ
Muscleȱ functionȱ inȱ pregnancyȱ hasȱ beenȱ investigatedȱ inȱ 1ȱ studyȱ usingȱ electromyographyȱ (217).ȱ Theȱ resultsȱ indicatedȱ thatȱ reducedȱ backȱ muscleȱ activityȱ atȱ theȱ beginningȱ ofȱ pregnancyȱ leadsȱ toȱ moreȱ painȱ andȱ disabilityȱ throughoutȱtheȱpregnancy.ȱLowȱenduranceȱofȱbackȱandȱhipȱmusclesȱhasȱbeenȱ reportedȱinȱwomenȱwithȱlongstandingȱPGPȱandȱlumbarȱpainȱafterȱpregnancyȱ (168).ȱItȱwasȱindicatedȱthatȱmuscularȱinsufficiencyȱmayȱbeȱanȱimportantȱfactorȱ regardingȱ persistentȱ problems.ȱ Itȱ isȱ unknownȱ ifȱ theȱ reportedȱ insufficiencyȱ developedȱ dueȱ toȱ longstandingȱ problemsȱ orȱ ifȱ theȱ womenȱ alreadyȱ hadȱ muscularȱinsufficiencyȱearlyȱonȱinȱtheȱpregnancy.ȱ
ȱ
Pregnancyȱ causesȱ biomechanicalȱ andȱ hormonalȱ changesȱ toȱ theȱ stabilisingȱ systemȱ ofȱ theȱ lumbopelvicȱ areaȱ forȱ allȱ women,ȱ howeverȱ notȱ allȱ getȱ LBP.ȱ Theȱ previouslyȱ suggestedȱ “hypermobilityȱ hypothesis,”ȱ asȱ aȱ causeȱ ofȱ PGP,ȱ canȱ beȱ translatedȱintoȱtheȱinabilityȱofȱtheȱmusculoligamentousȱsystemȱtoȱcompensateȱ forȱtheȱincreasedȱlaxityȱofȱtheȱpelvicȱjointsȱthroughȱdynamicȱstabilization.ȱItȱisȱ possibleȱ thatȱ theȱ relationsȱ areȱ notȱ linear,ȱ butȱ ratherȱ areȱ relatedȱ toȱ aȱ certainȱ threshold.ȱ
Gaitȱ
Gait,ȱwithȱitsȱunilateralȱloading,ȱrequiresȱlumbopelvicȱstability.ȱAȱprerequisiteȱ forȱstabilityȱisȱadequateȱmuscleȱfunctionȱandȱthereȱareȱindicationsȱthatȱmusclesȱ andȱ theirȱ biomechanicalȱ conditionsȱ changeȱ duringȱ pregnancy.ȱ Pregnantȱ womenȱ areȱ sometimesȱ describedȱ asȱ havingȱ anȱ alteredȱ gaitȱ pattern,ȱ “aȱ waddlingȱ gait,”(150)ȱ definedȱ asȱ anȱ increasedȱ baseȱ ofȱ supportȱ (23).ȱ Byȱ waddling,ȱ theȱ womenȱ avoidȱ rotationȱ ofȱ theȱ lumbopelvicȱ regionȱ andȱ therebyȱ decreaseȱdemandsȱonȱstability.ȱȱ
ȱ
Theȱnaturalȱcustomaryȱwalkingȱspeedȱforȱadultsȱisȱfromȱ1.0ȱtoȱ1.67ȱm/sȱ(248).ȱ Inȱhealthyȱpregnantȱwomen,ȱcomfortableȱwalkingȱspeedȱhasȱbeenȱreportedȱinȱ someȱstudiesȱtoȱbeȱlowerȱcomparedȱtoȱnonpregnantȱwomenȱ(161,ȱ266),ȱandȱnotȱ changedȱinȱanotherȱ(68).ȱ
ȱ
WomenȱwithȱPGPȱreportȱactivityȱlimitationȱinȱwalkingȱ(66,ȱ85,ȱ136,ȱ150,ȱ264).ȱ Maximumȱ gaitȱ velocityȱ duringȱ walkingȱ wasȱ studiedȱ onȱ aȱ treadmillȱ inȱ 9ȱ womenȱ withȱ persistentȱ PGPȱ postpartumȱ (265).ȱ Maximumȱ attainableȱ walkingȱ speedȱ variedȱ greatlyȱ inȱ womenȱ withȱ PGPȱ (0.17ȱ Ȭ1.50ȱ m/s)ȱ asȱ comparedȱ toȱ healthyȱ controls,ȱ whereȱ allȱ womenȱ reachedȱ theȱ highestȱ levelȱ (1.50ȱ m/s).ȱ Theȱ authorȱ speculatedȱ thatȱ muscleȱ coordinationȱ parametersȱ wereȱ perhapsȱ responsibleȱforȱtheȱdifference.ȱ
CONSEQUENCESȱOFȱPREGNANCYȬRELATEDȱLOWȱBACKȱ PAINȱ
Inȱ backȱ painȱ research,ȱ recommendedȱ studyȱ domainsȱ includeȱ genericȱ healthȱ status,ȱ pain,ȱ backȬspecificȱ function,ȱ workȱ disability,ȱ andȱ patientȱ satisfactionȱ (29).ȱ
ȱ
HealthȬrelatedȱqualityȱofȱlifeȱ
Accordingȱ toȱ theȱ Worldȱ Healthȱ Organisationȱ (WHO),ȱ healthȱ isȱ “aȱ stateȱ ofȱ completeȱphysical,ȱmentalȱandȱsocialȱwellȬbeing,ȱandȱnotȱmerelyȱtheȱabsenceȱofȱ disease”ȱ (254).ȱ Healthȱ outcomeȱ researchȱ hasȱ restrictedȱ toȱ usingȱ theȱ conceptȱ
“healthȬrelatedȱ qualityȱ ofȱ life”ȱ (HRQL)ȱ thatȱ addressesȱ theȱ consequencesȱ ofȱ diseaseȱ and/orȱ impairment,ȱ ratherȱ thanȱ aȱ specificȱ assessmentȱ ofȱ pathology,ȱ diseaseȱorȱimpairmentȱthatȱisȱatȱtheȱorganȱorȱbodyȱsystemȱlevelȱ(102).ȱHRQLȱ includesȱ theȱ perceptionȱ ofȱ anȱ individualȱ ofȱ hisȱ orȱ herȱ degreeȱ ofȱ physical,ȱ psychologicalȱandȱsocialȱwellȬbeingȱandȱtheȱimpactȱtheȱillnessȱhasȱonȱdailyȱlifeȱ (87,ȱ102).ȱ
ȱ
InȱaȱSwedishȱpopulationȱsurvey,ȱwomenȱreportedȱaȱsignificantlyȱlowerȱHRQLȱ thanȱ men;ȱ specificallyȱ inȱ theȱ ageȱ groupsȱ 20Ȭ29,ȱ 30Ȭ39ȱ andȱ 60Ȭ69ȱ yearsȱ (37).ȱ Duringȱ normalȱ pregnancy,ȱHRQLȱ isȱ reportedlyȱ decreasedȱ (94).ȱWellȬbeingȱ inȱ pregnancyȱ isȱ affectedȱ byȱ severalȱ symptomsȱ suchȱ asȱ nauseaȱ (33),ȱ sleepingȱ disordersȱ (209)ȱ andȱ LBP.ȱ Onlyȱ 2ȱ pregnancyȬrelatedȱ LBPȱ studiesȱ wereȱ identifiedȱ thatȱ measuredȱ HRQL.ȱ Inȱ lateȱ pregnancy,ȱ womenȱ reportedȱ lowerȱ HRQLȱ thanȱ nonpregnantȱ healthyȱ womenȱ (173).ȱ Womenȱ withȱ backȱ painȱ reportedȱ theȱ mostȱ impairedȱ HRQL.ȱ Inȱ aȱ 2Ȭyearȱ followȬupȱ ofȱ aȱ randomisedȱ controlledȱ trialȱ withȱ treatmentȱ forȱ persistentȱ PGP,ȱ womenȱ whoȱ improvedȱ inȱ painȱ andȱ disabilityȱ reportedȱ comparableȱ HRQLȱ scoresȱ onȱ theȱ Shortȱ Formȱ 36ȱ HealthȱSurveyȱ(SFȬ36)ȱtoȱnormalȱscoresȱfromȱaȱgeneralȱNorwegianȱpopulationȱ (226).ȱ Onȱ theȱ contrary,ȱ theȱ controlȱ groupȱ demonstratedȱ lowerȱ scoresȱ ofȱ physicalȱhealthȱbutȱnormalȱscoresȱofȱmentalȱhealthȱonȱtheȱSFȬ36.ȱ Itȱwouldȱbeȱ interestingȱ toȱ evaluateȱ howȱ pregnantȱ womenȱ estimateȱ theirȱ HRQLȱ inȱ earlyȱ pregnancyȱ andȱ compareȱ theȱ impactȱ onȱ healthȱ forȱ differentȱ typesȱ ofȱ LBPȱ experiencedȱ duringȱ pregnancy.ȱ Sinceȱ economicȱ analysisȱ ofȱ PGPȱ hithertoȱ isȱ limitedȱtoȱsickȱleaveȱcosts,ȱthereȱisȱaȱneedȱforȱanȱinstrumentȱthatȱcanȱbeȱusedȱinȱ formalȱ decisionȱ analysisȱ andȱ costȬeffectivenessȱ analysis,ȱ whereȱ PGPȱ canȱ beȱ relatedȱtoȱotherȱconditions.ȱThereȱisȱ aȱlackȱofȱknowledgeȱregardingȱHRQLȱinȱ earlyȱpregnancyȱinȱwomenȱwithȱdifferentȱtypesȱofȱLBP.ȱ
Painȱ
Painȱ isȱ aȱ subjectiveȱ experienceȱ andȱ includesȱ severalȱ components.ȱ Painȱ intensity,ȱdurationȱandȱlocalisationȱareȱincludedȱinȱtheȱsensoryȬdiscriminativeȱ component,ȱ andȱ itȱ isȱ influencedȱ byȱ emotionsȱ (affectiveȬmotivationalȱ component)ȱ asȱ wellȱ asȱ thoughts,ȱ beliefsȱ andȱ previousȱ experiencesȱ inȱ lifeȱ (evaluativeȬcognitiveȱ component)(147,ȱ 148).ȱ Measuresȱ ofȱ painȱ severityȱ areȱ
differentȱfromȱmeasuresȱofȱpainȱaffectȱ(261).ȱPainȱseverityȱisȱaȱglobalȱconstructȱ measuredȱ byȱ painȱ intensityȱandȱ interferenceȱ withȱ activities.ȱ Painȱaffectȱ isȱ theȱ degreeȱ ofȱ emotionalȱ arousalȱ orȱ changesȱ inȱ actionȱ readinessȱ causedȱ byȱ theȱ sensoryȱexperienceȱofȱpain.ȱPainȱisȱthusȱaȱmultidimensionalȱconstructȱandȱnoȱ consensusȱexistsȱasȱtoȱhowȱtoȱmeasureȱorȱclassifyȱpain.ȱChronicȱpainȱhasȱbeenȱ definedȱ asȱ “…thatȱ whichȱ persistsȱ beyondȱ theȱ normalȱ timeȱ ofȱ healing”(98).ȱ Persistentȱbackȱpainȱhasȱbeenȱdefinedȱasȱpainȱthatȱisȱpresentȱmostȱofȱtheȱtimeȱ forȱ aȱ periodȱ ofȱ 6ȱ monthsȱ orȱ moreȱ duringȱ theȱ priorȱ yearȱ (81).ȱ However,ȱ recurrentȱ painȱ episodesȱ thatȱ lastȱ lessȱ thanȱ 6ȱ monthsȱ mayȱ beȱ aȱ formȱ ofȱ persistentȱpainȱ(261).ȱThroughoutȱthisȱthesis,ȱtheȱtermȱpersistentȱpainȱisȱusedȱ insteadȱ ofȱ chronicȱ painȱ andȱ isȱ definedȱ asȱ recurrentȱ episodesȱ orȱ painȱ presentȱ mostȱofȱtheȱtimeȱǃ12ȱweeks.ȱ
ȱ
Theȱ frequencyȱ inȱ whichȱ painȱ shouldȱ beȱ measuredȱ inȱ orderȱ toȱ obtainȱ anȱ accurateȱpictureȱofȱtheȱpainȱexperienceȱisȱaȱmatterȱofȱdiscussion.ȱMeanȱpresentȱ painȱ intensityȱ scoresȱ haveȱ beenȱ shownȱ toȱ correlateȱ (ǃ0.80)ȱ withȱ averageȱ painȱ intensityȱscoresȱfromȱtheȱpreviousȱweekȱ(52).ȱHowever,ȱitȱisȱstillȱcontroversialȱ asȱ toȱ whetherȱ orȱ notȱ theȱ useȱ ofȱ aȱ singleȱ ratingȱ ofȱ currentȱ painȱ isȱ moreȱ appropriateȱthanȱtheȱuseȱofȱanȱaverageȱpainȱratingȱoverȱaȱspecificȱperiodȱ(28,ȱ 52).ȱAȱpainȱdrawingȱisȱanȱoutlineȱofȱtheȱbodyȱonȱwhichȱtoȱmarkȱpainȱlocationsȱ (200).ȱItȱisȱcommonlyȱusedȱtoȱevaluateȱandȱdescribeȱpainȱlocations,ȱwhichȱhaveȱ beenȱshownȱtoȱbeȱrelatedȱtoȱdisabilityȱ(172).ȱ
ȱ
Painȱintensityȱinȱpregnantȱwomenȱwithȱbackȱpainȱhasȱbeenȱevaluatedȱatȱoneȱorȱ severalȱtimeȱpointsȱduringȱpregnancyȱ(85,ȱ116,ȱ175,ȱ228),ȱasȱwellȱasȱpostpartumȱ (166,ȱ 176,ȱ 182).ȱ Fewȱ authorsȱ haveȱ classifiedȱ backȱ painȱ andȱ reportedȱ painȱ intensityȱ amongȱ patientsȱ subgroupedȱ forȱ differentȱtypesȱ ofȱ pain.ȱ Inȱ pregnantȱ women,ȱnoȱdifferenceȱinȱpainȱintensityȱwasȱidentifiedȱamongȱtheȱthreeȱpatientȱ painȱ subgroups:ȱ thoracicȱ pain,ȱ lumbarȱ painȱ andȱ posteriorȱ pelvicȱ painȱ (228).ȱ However,ȱsomeȱwomenȱbelongedȱtoȱ2ȱsubgroupsȱandȱthereȱwasȱlargeȱspreadȱ inȱtheȱnumberȱofȱgestationalȱweeksȱ(12Ȭ40),ȱwhichȱmakesȱtheȱresultsȱdifficultȱtoȱ interpret.ȱ Inȱ anotherȱ study,ȱ atȱ 7ȱ monthsȱ postpartumȱ noȱ differenceȱ inȱ painȱ intensityȱ wasȱ foundȱ betweenȱ patientsȱ groupedȱ accordingȱ toȱ theȱ followingȱ typesȱ ofȱ pain:ȱ posteriorȱ pelvicȱ pain,ȱ lumbarȱ pain,ȱ mixedȱ painȱ andȱ noȱ painȱ localisationȱ (166).ȱ Thereȱ isȱ aȱ lackȱ ofȱ knowledgeȱ regardingȱ painȱ intensityȱ inȱ earlyȱpregnancyȱinȱwomenȱwithȱdifferentȱtypesȱofȱLBP.ȱ
ȱ
Disabilityȱ
Theȱ consequencesȱ ofȱ LBPȱ areȱ relatedȱ toȱ theȱ functioningȱ ofȱ patients.ȱ Functioningȱ isȱ aȱ generalȱ termȱ forȱ allȱ bodyȱ functions,ȱ activities,ȱ andȱ participationȱ fromȱ theȱ healthyȱ perspectiveȱ accordingȱ toȱ theȱ Internationalȱ Classificationȱ ofȱ Functioning,ȱ Disabilityȱ andȱ Healthȱ (ICF)ȱ (ICFȱ 2001)(255).ȱ Disabilityȱ isȱ aȱ generalȱ termȱ forȱ impairment,ȱ activityȱ limitations,ȱ andȱ participationȱrestrictionsȱfromȱtheȱproblematicȱaspect.ȱ
ȱ
Evaluationȱ ofȱ consequencesȱ ofȱ LBPȱ inȱ termsȱ ofȱ disabilityȱ isȱ importantȱ inȱ theȱ rehabilitationȱ processȱ forȱ identifyingȱ targetȱ areasȱ inȱ treatmentȱ strategies.ȱ Inȱ oneȱ ofȱ theȱ mostȱ commonlyȱ usedȱ backȬspecificȱ measuresȱ ofȱ selfȬreportedȱ functioning,ȱtheȱOswestryȱDisabilityȱIndexȱ(ODI)ȱ(29),ȱdisabilityȱisȱdefinedȱasȱ
“theȱlimitationsȱofȱaȱpatient’sȱperformanceȱcomparedȱwithȱthatȱofȱaȱfitȱperson”ȱ (accordingȱ toȱ Garradȱ andȱ Bennettȱ (1971)ȱ inȱ Fairbank’sȱ article)(64).ȱ Thisȱ definitionȱ isȱ reasonablyȱ confinedȱ toȱ disabilityȱ accordingȱ toȱ theȱ WHOȱ definition.ȱ
ȱ
Pregnantȱ womenȱ reportedȱ restrictionsȱ inȱ activitiesȱ ofȱ dailyȱ life,ȱ howeverȱ pregnantȱ womenȱ withȱ backȱ painȱ reportedȱ significantlyȱ moreȱ restrictionsȱ inȱ physicalȱ abilitiesȱ (173).ȱ LBPȱ inȱ pregnancyȱ isȱ sometimesȱ lookedȱ uponȱ asȱ aȱ normalȱ consequenceȱ ofȱ pregnancyȱ (72,ȱ 134).ȱ Yet,ȱ aȱ thirdȱ ofȱ pregnantȱ womenȱ reportȱ LBPȱ asȱ aȱ severeȱ problemȱ whichȱ interferesȱ withȱ activitiesȱ ofȱ dailyȱ lifeȱ andȱ compromisesȱ theirȱ abilityȱ toȱ workȱ (116,ȱ 138,ȱ 177).ȱ Pregnantȱ womenȱ whoȱ consultedȱphysicalȱtherapistsȱbecauseȱofȱPGP,ȱreportedȱaȱconsiderableȱlevelȱofȱ complaintsȱinȱactivitiesȱofȱdailyȱlivingȱsuchȱasȱwalking,ȱstanding,ȱsitting,ȱlyingȱ down,ȱ andȱ changingȱ positionsȱ (210).ȱ Inȱ anotherȱ study,ȱ aȱ highȱ proportionȱ ofȱ womenȱwithȱPGPȱcouldȱnoȱlongerȱcarryȱoutȱactivitiesȱsuchȱasȱlifting,ȱcarrying,ȱ andȱvacuumȬcleaningȱbyȱthemselvesȱ(121).ȱOnȱtheȱcontrary,ȱinȱaȱsmallȱstudy,ȱ lowȬgradeȱdisabilityȱwasȱreportedȱbyȱtheȱmajorityȱofȱwomenȱwithȱbackȱpainȱinȱ lateȱpregnancyȱ(186).ȱ
ȱ
ConsequencesȱofȱpregnancyȬrelatedȱLBPȱhaveȱthusȱprimarilyȱbeenȱreportedȱinȱ termsȱofȱactivitiesȱthatȱproduceȱorȱincreaseȱpainȱ(66,ȱ85,ȱ136,ȱ138,ȱ177,ȱ210)ȱasȱ wellȱ asȱ inȱ termsȱ ofȱpainȱ intensityȱandȱ sickȱ leaveȱ (109,ȱ183,ȱ231).ȱAccordingly,ȱ consequencesȱ onȱ disabilityȱ andȱ HRQLȱ wereȱ mainlyȱ notȱ describedȱ withȱ establishedȱ measurementȱ toolsȱ atȱ theȱ planningȱ ofȱ theȱ presentȱ study.ȱ Furthermore,ȱ thereȱ isȱ aȱ lackȱ ofȱ knowledgeȱ regardingȱ disabilityȱ andȱ HRQLȱ inȱ earlyȱpregnancyȱinȱwomenȱwithȱdifferentȱtypesȱofȱLBP.ȱ
DEPRESSIONȱ
Fromȱ researchȱ onȱ nonpregnancyȬrelatedȱ LBP,ȱ itȱ hasȱ beenȱ shownȱ thatȱ psychosocialȱ factorsȱ playȱ aȱ roleȱ inȱ LBPȱ (8,ȱ 79,ȱ 114).ȱ Inȱ aȱ generalȱ Swedishȱ community,ȱ theȱ annualȱ incidenceȱ ofȱ firstȱ timeȱ depressionȱ inȱ womenȱ wasȱ reportedȱasȱ7.6ȱperȱ1000ȱpersonȱyearsȱ(208).ȱAmongȱfemaleȱpatientsȱinȱprimaryȱ healthcareȱinȱtheȱNordicȱcountries,ȱtheȱreportedȱprevalenceȱofȱdepressionȱwasȱ 9.9Ȭ14.2%ȱ(158).ȱAlthoughȱitȱisȱnotȱclearȱwhichȱcomesȱfirst,ȱdepressionȱorȱLBP,ȱ itȱhasȱbeenȱshownȱthatȱaȱdepressedȱmoodȱincreasesȱtheȱriskȱforȱpainȱproblemsȱ andȱthatȱpsychosocialȱvariablesȱareȱclearlyȱlinkedȱtoȱtheȱtransitionȱfromȱacuteȱ toȱpersistentȱpainȱdisabilityȱ(129).ȱTheȱriskȱofȱsufferingȱfromȱdepressionȱwhenȱ havingȱ backȱ painȱ hasȱ beenȱ reportedȱ toȱ increaseȱ byȱ 1.40ȱ toȱ 2.06ȱ inȱ aȱ generalȱ populationȱ(144).ȱOneȱaimȱofȱtheȱphysicalȱtherapyȱexaminationȱisȱtoȱidentifyȱorȱ excludeȱ conditionsȱ thatȱ canȱ contraindicateȱ treatmentȱ orȱ reduceȱ theȱ effectivenessȱofȱinterventionȱ(83).ȱItȱhasȱbeenȱreportedȱthatȱprimaryȱhealthȱcareȱ physiciansȱ (196),ȱ asȱ wellȱ asȱ physiotherapistsȱ (83),ȱ doȱ notȱ accuratelyȱ identifyȱ symptomsȱofȱdepression.ȱ
ȱ
Accordingȱ toȱ theȱ Diagnosticȱ andȱ Statisticalȱ Manualȱ ofȱ Mentalȱ DisordersȬIVȱ classificationsȱ (7),ȱ depressiveȱ symptomsȱ areȱ definedȱ asȱ theȱ following:ȱ depressedȱmood,ȱlossȱofȱinterestȱorȱpleasure,ȱalteredȱappetite,ȱweightȱorȱsleepȱ patterns,ȱpsychomotorȱagitation/retardation,ȱfatigue/lossȱofȱenergy,ȱfeelingsȱofȱ worthlessness,ȱ selfȬreproachȱ orȱ inappropriateȱ guilt,ȱ diminishedȱ abilityȱ toȱ think,ȱ concentrateȱ orȱ indecisivenessȱ andȱ recurrentȱ thoughtsȱ ofȱ deathȱ orȱ suicidalȱideation.ȱAȱmajorȱdepressionȱisȱdefinedȱasȱ5ȱorȱmoreȱofȱtheȱdepressiveȱ symptomsȱthatȱhaveȱbeenȱpresentȱduringȱaȱ2Ȭweekȱperiodȱandȱincludeȱatȱleastȱ depressedȱmoodȱorȱlossȱofȱinterestȱorȱpleasure.ȱ
Postpartumȱdepressionȱ
Depressionȱisȱapproximatelyȱtwiceȱasȱcommonȱinȱwomenȱasȱitȱisȱinȱmen,ȱandȱ thereȱ isȱ aȱ peakȱ inȱ depressionȱ debutȱ duringȱ theȱ childbearingȱ yearsȱ (251).ȱ Emotionalȱ problemsȱ inȱ relationȱ toȱ pregnancyȱ mayȱ fallȱ intoȱ 3ȱ categoriesȱ thatȱ rangeȱ fromȱ theȱ lighterȱ maternalȱ blues,ȱ overȱ postpartumȱ depression,ȱ intoȱ theȱ moreȱ severeȱ psychosis.ȱ Maternalȱ bluesȱ areȱ consideredȱ aȱ relativelyȱ mild,ȱ selfȬ limitingȱ moodȱ stateȱ thatȱ occursȱ inȱ theȱ earlyȱ postpartumȱ period,ȱ andȱ affectsȱ betweenȱ 50Ȭ80%ȱ ofȱ mothers.ȱ Postpartumȱ psychosisȱ is,ȱ onȱ theȱ contrary,ȱ aȱ rareȱ conditionȱaffectingȱ0.1Ȭ0.4%ȱofȱmothersȱ(223,ȱ251).ȱAroundȱ10–20%ȱofȱwomenȱ sufferȱ fromȱ depressiveȱ illnessȱ duringȱ pregnancyȱ orȱ theȱ firstȱ yearȱ postpartumȱ (46,ȱ 76,ȱ 104).ȱ Mostȱ womenȱ experienceȱ theȱ depressionȱ onsetȱ withinȱ 6ȱ weeksȱ
ȱ
postpartum,ȱandȱtheȱdurationȱisȱtypicallyȱ2ȱtoȱ6ȱmonthsȱ(43).ȱIfȱleftȱuntreated,ȱitȱ mayȱstillȱpersistȱforȱ1ȱyearȱafterȱdeliveryȱinȱupȱtoȱ25%ȱofȱwomenȱ(32).ȱ
ȱ
Whenȱ studyingȱ postpartumȱ depression,ȱ itȱ isȱ essentialȱ toȱ excludeȱ itemsȱ thatȱ mightȱ reflectȱ physicalȱ discomfortȱ andȱ therebyȱ confuseȱ depressionȱ withȱ theȱ somaticȱeffectsȱofȱpregnancyȱandȱchildbirth.ȱThisȱisȱaȱprimaryȱfeatureȱwithȱtheȱ EdinburghȱPostnatalȱDepressionȱScaleȱ(EPDS)(45,ȱ104).ȱAlthoughȱtheȱEPDSȱisȱ notȱdiagnostic,ȱitȱisȱaȱvalidȱscreeningȱmeasureȱ(86).ȱFiveȱofȱtheȱitemsȱinȱEPDSȱ areȱ concernedȱ withȱ dysphoricȱ moodȱ itself,ȱ twoȱ withȱ anxiety,ȱ andȱ oneȱ eachȱ withȱguilt,ȱsuicidalȱideasȱandȱnoncoping.ȱ
ȱ
InȱaȱpostalȱsurveyȱinȱAustralia,ȱpregnancyȬrelatedȱbackȱpainȱwasȱfoundȱtoȱbeȱ associatedȱ withȱ aȱ 2.2ȱ increasedȱ riskȱ ofȱ postpartumȱ depressionȱ (35).ȱ Inȱ aȱ treatmentȱ studyȱ forȱ postpartumȱ PGP,ȱ noȱ differenceȱ inȱ mentalȱ disordersȱ wasȱ foundȱ betweenȱ womenȱ whoȱ hadȱ receivedȱ specificȱ orȱ nonspecificȱ treatmentȱ strategiesȱ forȱ PGPȱ (226).ȱ Furthermore,ȱ postpartumȱ depressionȱ hasȱ beenȱ associatedȱ withȱ sickȱ leaveȱ inȱ pregnancyȱ dueȱ toȱ pregnancyȬrelatedȱ complicationsȱ (103).ȱ Inȱ theȱ Scandinavianȱ countries,ȱ backȱ painȱ isȱ theȱ mostȱ frequentȱreasonȱforȱsickȱleaveȱduringȱpregnancyȱ(230,ȱ264).ȱThereforeȱitȱisȱalsoȱ relevantȱ toȱ evaluateȱ theȱ associationȱ betweenȱ LBPȱ andȱ depression.ȱ Clinicalȱ classificationȱ ofȱ theȱ experiencedȱ LBPȱ wouldȱ giveȱ additionalȱ informationȱ regardingȱpossibleȱdifferencesȱinȱdepressiveȱsymptomsȱbetweenȱtypesȱofȱLBP.ȱ ȱ
Inȱ conclusionȱ LBPȱ isȱ oneȱ ofȱ theȱ mostȱ commonȱ complicationsȱ ofȱ pregnancy,ȱ withȱnegativeȱconsequencesȱforȱtheȱaffectedȱwoman,ȱasȱwellȱasȱforȱsociety.ȱTheȱ consequencesȱ needȱ toȱ beȱ betterȱ describedȱ forȱ theȱ differentȱ subtypesȱ ofȱ LBP.ȱ Thereȱ areȱ biomechanicalȱ changesȱ thatȱ influenceȱ lumbopelvicȱ stabilityȱ duringȱ pregnancyȱandȱsomeȱindicationsȱthatȱthereȱmayȱbeȱinterindividualȱdifferencesȱ inȱmuscularȱadaptationȱtoȱtheȱchanges.ȱIdentificationȱofȱwomenȱwhoȱareȱatȱriskȱ forȱ persistentȱ postpartumȱ LBPȱ isȱ ofȱ valueȱ forȱ clinicalȱ management.ȱ Likewise,ȱ evaluationȱofȱpossibleȱinfluencesȱonȱcomorbidityȱisȱimportant.ȱ
AIMSȱOFȱTHEȱTHESISȱ
Theȱoverallȱaimsȱofȱthisȱthesisȱwereȱtheȱfollowing:ȱ ȱ
x toȱinvestigateȱifȱthereȱwereȱdifferencesȱinȱhealthȬrelatedȱqualityȱofȱlife,ȱ painȱintensity,ȱdisability,ȱdepressiveȱsymptomsȱorȱmuscleȱfunction,ȱinȱ subgroupsȱofȱlowȱbackȱpainȱinȱrelationȱtoȱpregnancy,ȱ
ȱ
x toȱidentifyȱpredictorsȱforȱpersistentȱpregnancyȬrelatedȱpelvicȱgirdleȱpainȱ orȱcombinedȱpainȱpostpartum.ȱ
ȱ
ȱ ȱ Theȱspecificȱaimsȱofȱthisȱthesisȱwereȱtheȱfollowing:ȱ ȱ
x toȱdescribeȱtheȱprevalenceȱofȱclinicallyȱclassifiedȱsubgroupsȱofȱlowȱbackȱ painȱinȱaȱcohortȱofȱwomenȱduringȱpregnancyȱandȱpostpartumȱ(Iȱ&ȱIV),ȱ ȱ
x toȱ evaluateȱ ifȱ thereȱwasȱaȱ disparityȱ inȱ theȱ courseȱofȱ clinicallyȱ classifiedȱ subgroupsȱ ofȱ lowȱ backȱ painȱ inȱ pregnancyȱ andȱ postpartum,ȱ andȱ toȱ predictȱearlyȱonȱinȱpregnancyȱwhoȱwasȱatȱriskȱforȱpersistentȱpregnancyȬ relatedȱpelvicȱgirdleȱpainȱorȱcombinedȱpainȱ(IV),ȱ
ȱ
x toȱ evaluateȱ theȱ consequencesȱ ofȱ pregnancyȬrelatedȱ lowȱ backȱ painȱ inȱ termsȱ ofȱ healthȬrelatedȱ qualityȱ ofȱ life,ȱ painȱ intensity,ȱ andȱ disabilityȱ forȱ differentȱsubgroupsȱofȱlowȱbackȱpainȱduringȱpregnancyȱ(I),ȱ
ȱ
x toȱ evaluateȱ ifȱ thereȱ wasȱ anȱ associationȱ betweenȱ lowȱ backȱ painȱ postpartumȱ andȱ depressiveȱ symptomsȱ andȱ toȱ evaluateȱ ifȱ thereȱ wasȱ aȱ differenceȱ inȱ theȱ prevalenceȱ ofȱ depressiveȱ symptomsȱ amongȱ differentȱ subgroupsȱofȱlowȱbackȱpainȱ(II),ȱ
ȱ
x toȱ evaluateȱ muscleȱ functionȱ duringȱ pregnancyȱ andȱ postpartumȱ inȱ womenȱ withoutȱ lowȱ backȱ painȱ andȱ inȱ subgroupsȱ ofȱ womenȱ withȱ lowȱ backȱpainȱ(III).ȱ
ȱ
ȱ
MATERIALSȱANDȱMETHODSȱ
DESIGNȱ
Theȱ studyȱ consistedȱ ofȱ 2ȱ parts:ȱ aȱ prospectiveȱ cohortȱ studyȱ andȱ aȱ RCTȱ whereȱ womenȱwithȱpersistentȱpostpartumȱPGPȱorȱcombinedȱpainȱwereȱfollowedȱforȱ2ȱ yearsȱafterȱpregnancy.ȱThisȱthesisȱcomprisesȱdataȱcollectedȱinȱtheȱprospectiveȱ cohortȱ studyȱ atȱ theȱ evaluationȱ duringȱ gestationalȱ weeksȱ 12Ȭ18ȱ andȱ atȱ theȱ evaluationȱ3ȱmonthsȱpostpartumȱ(Figureȱ1).ȱ
ȱ
Evenȱ thoughȱ PGPȱ mayȱ start,ȱ onȱ averageȱ inȱ theȱ 18thȱ gestationalȱ weekȱ (267)ȱ itȱ wasȱ theȱ intentionȱ toȱ evaluateȱ asȱ earlyȱ asȱ possibleȱ duringȱ pregnancyȱ butȱ pastȱ theȱ pointȱ ofȱ highestȱ riskȱ forȱ miscarriage.ȱ Anotherȱ limitingȱ factorȱ forȱ theȱ timeȱ pointȱ ofȱ inclusionȱ wasȱ thatȱ theȱ womenȱ neededȱ toȱ beȱ ableȱ toȱ performȱ theȱ muscleȱtestsȱbeforeȱtheȱgrowingȱabdomenȱhinderedȱtheȱtesting.ȱAdditionally,ȱitȱ wasȱdesiredȱtoȱstudyȱpotentialȱpredictiveȱfactorsȱearlyȱonȱinȱpregnancyȱwhenȱ symptomsȱ wereȱ lessȱ established.ȱ Theȱ secondȱ evaluationȱ wasȱ atȱ threeȱ monthsȱ postpartumȱsinceȱlittleȱimprovementȱfromȱpregnancyȬrelatedȱPGPȱoccursȱafterȱ 3ȱmonthsȱ(112,ȱ176,ȱ182).ȱ
THE PART OF THE STUDY INCLUDED IN THE THESIS TIME
EQ-5D PAIN VAS ODI MUSCLE FUNCTION GAIT
ȱ PREGNANTȱ
CLASSIFICATIONȱCLASSIFICATION EQ-5D PAIN VAS ODI MUSCLE FUNCTION GAIT
EQ-5D PAIN VAS ODI EPDS MUSCLEȱ FUNCTION ȱ GAIT
CLASSIFICATIONȱ SPECIFIC STABILISATION CLINICAL NATURAL COURSE GESTATIONAL WEEKS 12-18 3 MONTHS AFTER DELIVERY
3, 6, 12, 24 MONTHS AFTER INCLUSION
E P D S ȱ
NO LBP LUMBAR PGP COMBINED PAIN
MaterialsȱandȱMethodsȱ 25
ȱ1. Flow chart of the study.ȱ
ȱ
STUDYȱPOPULATIONȱ
TheȱprenatalȱhealthcareȱsystemȱinȱSwedenȱservesȱalmostȱ100%ȱofȱtheȱcountry’sȱ pregnantȱwomen,ȱprovidingȱregularȱphysicalȱandȱpsychologicalȱhealthȱcheckȬ upsȱduringȱpregnancyȱandȱpostpartum.ȱSixȱmidwifesȱatȱ2ȱprenatalȱhealthcareȱ clinics,ȱhousedȱinȱaȱsociodemographicallyȱdiverseȱcommunityȱofȱ26000ȱpeople,ȱ wereȱ involvedȱ inȱ theȱ recruitmentȱ processȱ thatȱ lastedȱ 2ȱ years.ȱ Theȱ studiedȱ cohortȱwasȱcomprisedȱofȱallȱpregnantȱwomenȱconsecutivelyȱregisteredȱatȱtheȱ2ȱ prenatalȱ healthcareȱ clinics.ȱ SwedishȬspeakingȱ womenȱ withȱ anȱ expectedȱ normalȱ pregnancyȱ (asȱ determinedȱ byȱ theȱ midwives)ȱ wereȱ approachedȱ forȱ participationȱ duringȱ gestationalȱ weeksȱ 12Ȭ18.ȱ Womenȱ wereȱ excludedȱ ifȱ theyȱ hadȱ aȱ systemicȱ locomotorȱ disease,ȱ aȱ verifiedȱ diagnosisȱ ofȱ aȱ spinalȱ problemȱ duringȱtheȱpreviousȱ2ȱmonths,ȱorȱaȱhistoryȱofȱfracture,ȱneoplasm,ȱorȱpreviousȱ spinal,ȱpelvicȱorȱfemurȱsurgery.ȱ
MEASUREMENTSȱANDȱPROCEDURESȱ
Oneȱphysiotherapist,ȱ(AG)ȱscheduledȱtheȱparticipantsȱforȱassessmentȱandȱdidȱ allȱ theȱ evaluationsȱatȱ 1ȱ primaryȱ healthȱ careȱ clinic.ȱ Allȱ participantsȱ completedȱ questionnairesȱandȱwereȱphysicallyȱevaluatedȱduringȱgestationalȱweeksȱ12Ȭ18ȱ andȱ3ȱmonthsȱpostpartum.ȱEachȱfullȱassessmentȱtookȱapproximatelyȱ1.5ȱhoursȱ toȱcomplete.ȱ
SelfȬreportedȱquestionnairesȱ
First,ȱwhenȱchoosingȱaȱmeasurementȱtool,ȱitȱisȱnecessaryȱtoȱassessȱwhetherȱorȱ notȱtheȱinstrumentȱmeasuresȱtheȱappropriateȱconstructȱunderȱstudyȱandȱifȱitȱisȱ appropriateȱforȱtheȱparticularȱpopulationȱ(faceȱvalidity).ȱPriorȱtoȱtheȱstudy,ȱtheȱ questionnaireȱ wasȱ examinedȱ byȱ anȱ expertȱ inȱ PGPȱ andȱ filledȱ inȱ byȱ 5ȱ womenȱ withȱPGP,ȱwhoȱconfirmedȱtheȱfaceȱvalidity.ȱ
ȱ
Theȱ questionnaireȱ includedȱ backgroundȱ data,ȱ asȱ wellȱ asȱ questionsȱ regardingȱ urinaryȱ incontinence,ȱ activityȱ levelȱ (71),ȱ employmentȱ status,ȱ workȱ dissatisfaction,ȱ andȱ HRQL.ȱ Participantsȱ whoȱ hadȱ previouslyȱ experiencedȱ nonspecificȱLBPȱalsoȱansweredȱquestionsȱaboutȱsickȱleaveȱdueȱtoȱLBP,ȱwhetherȱ LBPȱhadȱhinderedȱtheirȱworkȱ duringȱtheȱpastȱ5ȱyears,ȱpresentȱpainȱintensity,ȱ andȱ disability.ȱ Theȱ postpartumȱ questionnaireȱ wasȱ theȱ sameȱ asȱ theȱ questionnaireȱ inȱ gestationalȱ weeksȱ 12Ȭ18ȱ exceptȱ forȱ specificȱ questionsȱ
regardingȱdelivery,ȱsuchȱasȱmodeȱofȱdelivery,ȱdeliveryȱposition,ȱvaginalȱcutsȱatȱ delivery,ȱbabyȱweight,ȱbreastȱfeedingȱasȱwellȱasȱquestionsȱaboutȱtreatmentȱandȱ treatmentȱeffectȱinȱtheȱcaseȱofȱLBP.ȱAlso,ȱpostpartum,ȱaȱdepressionȱscaleȱwasȱ added.ȱ Theȱ participantsȱ hadȱ theȱ opportunityȱ toȱ askȱ questionsȱ regardingȱ theȱ questionnaire,ȱifȱneeded.ȱ
HealthȬrelatedȱqualityȱofȱlifeȱ
TheȱEuropeanȱQualityȱofȱLifeȱ5ȱDimensionsȱQuestionnaireȱ(EQȬ5D)ȱ(199,ȱ234)ȱ wasȱusedȱforȱmeasuringȱHRQL.ȱTheȱdevelopmentȱofȱEQȬ5Dȱforȱtheȱassessmentȱ ofȱ HRQLȱ withinȱ populationȱ surveys,ȱ aimedȱ atȱ creatingȱ aȱ healthȱ stateȱ classificationȱ throughȱ whichȱ anȱ overallȱ indexȱ couldȱ beȱ derivedȱ usingȱ preferencesȱ fromȱ theȱ generalȱ population,ȱ andȱ therebyȱ enablingȱ calculationȱ ofȱ Qualityȱ Adjustedȱ Lifeȱ Yearsȱ (QALYs).ȱ QUALYsȱ areȱ quantitativeȱ estimatesȱ reflectingȱhowȱindividualsȱvalueȱhealthȱstates,ȱandȱareȱtypicallyȱscaledȱfromȱ0ȱ toȱ1.ȱQUALYsȱcanȱbeȱusedȱinȱeconomicȱanalysesȱ(42).ȱ
ȱ
TheȱEQȬ5DȱconsistsȱofȱtwoȱpartsȱthatȱmonitorȱHRQL.ȱTheȱfirstȱpartȱinvolvesȱaȱ healthȱstateȱclassificationȱschemeȱofȱ5ȱitemsȱwithȱ3ȱresponseȱcategoriesȱ(1ȱ=ȱnoȱ problems,ȱ 2ȱ =ȱ moderateȱ problems,ȱ andȱ 3ȱ =ȱ severeȱ problems).ȱ Theȱ questionsȱ involveȱ theȱ followingȱ dimensions:ȱ mobility,ȱ selfȱ care,ȱ usualȱ activities,ȱ pain/discomfort,ȱ andȱ anxiety/depression.ȱ Thereȱ areȱ 243ȱ (35)ȱ possibleȱ distinctȱ healthȱ states.ȱ Eachȱ healthȱ stateȱ hasȱ aȱ preferenceȱ valueȱ attachedȱ toȱ itȱ andȱ possibleȱvaluesȱrangeȱfromȱȬ0.59ȱtoȱ1.0ȱwhereȱ1.0ȱisȱoptimalȱhealth.ȱTheȱsecondȱ partȱ ofȱ EQȬ5Dȱ isȱ aȱverticalȱ20ȱ cmȱ VASȱrangingȱ fromȱ 0ȱ (worstȱ possibleȱ healthȱ state)ȱ toȱ 100ȱ (bestȱ possibleȱ healthȱ state),ȱ onȱ whichȱ theȱ respondentsȱ rateȱ howȱ theyȱ perceiveȱ theirȱ healthȱ onȱ thatȱ particularȱ day.ȱ Theȱ VASȱ isȱ notȱ usedȱ whenȱ derivingȱtheȱpreferenceȱvalue.ȱTheȱminimalȱimportantȱdifferenceȱ(MID)ȱforȱtheȱ EQȬ5Dȱscoreȱhasȱbeenȱreportedȱtoȱrangeȱbetweenȱ0.09Ȭ0.22ȱandȱforȱtheȱEQȬ5Dȱ VAS,ȱtheȱestimatesȱrangeȱfromȱ3.82ȱtoȱ8.43ȱ(216).ȱ
Painȱ
Painȱ intensityȱ wasȱ measuredȱ inȱ theȱ questionnairesȱ onȱ 2ȱ separateȱ 100ȱ mmȱ horizontalȱVAS,ȱwithȱtheȱendsȱlabeledȱasȱtheȱextremesȱofȱpainȱi.e.ȱ“noȱpain”ȱtoȱ
“worstȱ imaginableȱ pain”ȱ (97).ȱ Theȱ firstȱ VASȱ wasȱ usedȱ toȱ assessȱ presentȱ painȱ intensityȱandȱtheȱsecondȱVASȱwasȱusedȱtoȱassessȱaverageȱpainȱintensityȱduringȱ theȱpastȱweekȱ(52).ȱPainȱintensityȱwasȱalsoȱmeasuredȱwithȱaȱplasticȱVASȱrulerȱ withȱ aȱ slidingȱ marker,ȱ beforeȱ andȱ afterȱ eachȱ physicalȱ functioningȱ test.ȱ Aȱ previousȱstudyȱhasȱshownȱthatȱtheȱscoreȱchangesȱwithȱtheȱbestȱcutȬoffȱpointsȱ
