SOCIEDADE BRASILEIRA DE ORTOPEDIA E TRAUMATOLOGIA
w w w . r b o . o r g . b r
Review
Article
Rehabilitation
of
hamstring
muscle
injuries:
a
literature
review
夽
Gabriel
Amorim
Ramos,
Gustavo
Gonc¸alves
Arliani
∗,
Diego
Costa
Astur,
Alberto
de
Castro
Pochini,
Benno
Ejnisman,
Moisés
Cohen
UniversidadeFederaldeSãoPaulo,EscolaPaulistadeMedicina,DepartamentodeOrtopediaeTraumatologia,SãoPaulo,SP,Brazil
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Articlehistory:
Received4December2015 Accepted24February2016 Availableonline15December2016
Keywords:
Muscleskeletal/injuries Athleticinjuries
Musclestretchingexercises Physicaltherapymodalities
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Hamstringinjuriesareamongthemostfrequentinsports.Thehighrelapserateisa chal-lengeforsportsmedicineandhasagreatimpactonathletesandsportteams.Thetreatment goalistoprovidetheathletethesamefunctionallevelasbeforetheinjury.Thus,functional rehabilitationisveryimportanttothesuccessofthetreatment.Currently,severalphysical therapymodalitiesareused,accordingtothestageofthelesion,suchascryotherapy,laser therapy,therapeuticultrasound,therapeuticexercise,andmanualtherapy.However,the evidenceoftheeffectivenessofthesemodalitiesinmuscleinjuriesisnotfullyestablished duetothelittlescientificresearchonthetopic.Thisarticlepresentsanoverviewofthe physiotherapyapproachintherehabilitationofhamstringmuscleinjuries.
©2016SociedadeBrasileiradeOrtopediaeTraumatologia.PublishedbyElsevierEditora Ltda.ThisisanopenaccessarticleundertheCCBY-NC-NDlicense(http://
creativecommons.org/licenses/by-nc-nd/4.0/).
Reabilitac¸ão
nas
lesões
musculares
dos
isquiotibiais:
revisão
da
literatura
Palavras-chave:
Músculoesquelético/lesões Traumatismosematletas Exercíciosdealongamento muscular
Modalidadesdefisioterapia
r
e
s
u
m
o
Aslesõesdosisquiotibiaisestãoentreasmaisfrequentesdoesporte.Aaltataxaderecidivas representaumdesafioparaamedicinaesportivaeapresentagrandeimpactoparaatletase clubesesportivos.Oobjetivodotratamentoéproporcionaraoatletaomesmonívelfuncional anterioràlesão.Dessaforma,areabilitac¸ãofuncionalémuitoimportanteparaosucessodo tratamento.Atualmente,usam-seváriasmodalidadesfisioterápicasdeacordocomoestágio dalesão:crioterapia,laserterapia,ultrassomterapêutico,terapiamanualecinesioterapia. Entretanto,asevidênciasdaeficáciadessasmodalidadesnaslesõesmuscularesaindanão estãocompletamenteestabelecidas,devidoàbaixainvestigac¸ãocientíficasobreotema.O
夽
StudyconductedattheUniversidadeFederaldeSãoPaulo,EscolaPaulistadeMedicina,CentrodeTraumatologiadoEsporte, Depar-tamentodeOrtopediaeTraumatologia,SãoPaulo,SP,Brazil.
∗ Correspondingauthor.
E-mail:[email protected](G.G.Arliani).
http://dx.doi.org/10.1016/j.rboe.2016.12.002
presenteartigoapresentaumarevisãosobreaabordagemfisioterápicanareabilitac¸ãodas lesõesmuscularesdeisquiotibiais.
©2016SociedadeBrasileiradeOrtopediaeTraumatologia.PublicadoporElsevier EditoraLtda.Este ´eumartigoOpenAccesssobumalicenc¸aCCBY-NC-ND(http://
creativecommons.org/licenses/by-nc-nd/4.0/).
Introduction
Hamstringinjuriesaresomeofthemostfrequentinthefield ofsportsmedicine.1,2AprospectivestudybyElkstrandetal.3
demonstratedthattheyaccountfor37%ofmuscleinjuriesin professionalsoccerplayersandfor25%ofathletes’absence ingames.Otherstudiesindicatethatone-thirdofhamstring injuriesrelapse andthatmanyoftheserelapsestakeplace withinthefirsttwoweeksafterreturningtosport.4,5Thishigh
recurrenceratemayberelatedtoacombinationoffactors, suchasineffectiverehabilitationandinadequatecriteriafor returntosportpractice.
Thegoalsofhamstringinjuryrehabilitationaretoachieve the same functional level observed prior to injury and to allowforthereturntosportspracticewithminimalriskof recurrence.6 Manyinterventionsarewidelyusedtoachieve
fullrehabilitation.TheseincludePRICE(protection,rest,ice, compression, and elevation), to control the inflammatory process7; therapeutic exercises to strengthen and restore
thefunctionalityofthemusculature8;photothermaltherapy
forinflammationmodulation9;massageandmobilizationto
realignandrelievetensionofsofttissues10;jointandnerve
manualtherapy11,12;andfunctionalrehabilitation.However,
evidenceoftheeffectivenessofthesetreatmentmodalitiesis notyetfullyestablished,duetothesparsescientificresearch onthesubject.
Therefore,thepresentstudyaimedtoinvestigatethe cur-rent evidence on physicaltherapy approaches used inthe rehabilitationofhamstringinjuries.
Methods
AliteraturereviewinthedatabasesPubMed,LILACS,SciELO, andtheCochraneDatabaseofSystematicReviews(Cochrane Library)wasmade.Thefollowingkeywordswereused:muscle injury,hamstringsinjury,musclestrain,functional rehabilita-tion,andphysicaltherapy.
Theinclusioncriteriaforthisstudywerestudieswithhigh qualityevidence,suchassystematicreviews,meta-analyses, randomizedcontrolledtrials,andclassicalstudiesrelevantto theproposedgoals.Theexclusioncriteriawerearticlesthat didnotmatchtheproposedtheme.
Classification
Muscle injury is characterized bychanges inthe morpho-logicalandhistochemicalaspectsthatcreateafunctionality deficitintheaffectedsegment.13
Therearetwomajorformsofmuscularinjuryinsports: musclestrainand contusion.14 Strainisthemostcommon
muscleinjuryinsports,andisclassifiedasfollows:gradeI,in whichthereisminimalstructuraldisruptionandrapidreturn tonormalfunction;gradeII,inwhichthereisapartialrupture, withpainandsomelossoffunction;andgradeIII,inwhich acompletetissueruptureisobserved,withmuscular retrac-tionandfunctionaldisability.15Ekstrandetal.3demonstrated
thathamstringsarethemusclesmostaffectedbythistypeof injury.
Theotherformismusclecontusion,whichisadirectresult of externaltrauma forces,common incontact sports.Itis characterizedbythepresenceofpain,swelling,stiffness,and rangeofmotionrestriction.15Itcanaffectanymuscle,butthe
quadricepsand thegastrocnemiusarethemostcommonly affected.14
Anewcomprehensiveclassificationsystem,knownasthe Munichconsensus,wasdevelopedbyspecialists16and
distin-guishesfourtypesofinjury.Thefirstgroupisthefunctional muscle disorders, comprising type 1 (disorders related to overexertion)andtype2(disordersofneuromuscularorigin). Thesedisordersarecharacterizedbynotpresentingevidence ofmacroscopiclesionsinthemusclefiber.Theclassification alsoincludesstructuralmuscledisorders,comprisingtype3 (partialmuscleinjuries)andtype4(totalorsubtotallesions that maypresent tendonavulsion).Inthesecases,thereis macroscopicevidenceofinjury,i.e.,structuraldamage. Sub-classificationsaregivenforeachtype.
Injury
mechanism
Twospecificmechanismsaredescribedforhamstringinjuries, which appeartoinfluence thelocation and severity ofthe injury.Heiderscheitetal.6demonstratedthat,during
termi-nal swing phaseof running, the hamstringsabsorb elastic energytocontracteccentricallyandpromotedecelerationof thelimb’sadvanceinpreparationfortheinitialcontactofthe calcaneus.Inthisphase,musclesbecomemoresusceptibleto damage;thebicepsfemorismuscleisthemostaffected,asitis moreactivethanthesemitendinosusandsemimembranosus muscles.17,18
Another mechanismthat commonlydamages the proxi-malportionofthesemitendinosusmuscleisamovementof combinedhighpowerandextremerangeofhipflexionwith knee extension,whichbiomechanically matchesthe move-mentsofkicking,runninghurdles,andartisticdancing.19,20
Risk
factors
Modifiable factors comprise muscle imbalances, includ-ing the strength ratio of the quadriceps and hamstrings of the same limb, and the bilateral relationship of the hamstrings.22,23Anotherfactorismusclefatigue,since
stud-ieshave shownthat theincidenceofhamstring injuriesis higherinthelaststagesofmatches andcompetitive train-ing,whenthemusculatureisatahighleveloffatigue.24,25A
hamstringflexibilitydeficitisalsoconsideredbysomeauthors tobeariskfactor,26,27butitisnotconsensual,asother
stud-ieshaveshownthatflexibilitydeficitwasnotassociatedwith injury.28Duringtherehabilitationprocess,thephysical
ther-apistshouldidentifythesefactorssothatthereturnofthe athletetosportpracticecanbemoreeffective.21
Regardingthenon-modifiableriskfactors,historyof previ-oushamstringinjuryisnoteworthy,asmanyauthorsconsider ittobethemainriskfactorforhamstringinjury.29–31
Pathophysiology
Jarvinenetal.32describedthestagesofmuscleinjuryhealing:
Step1 destruction (threetosevendays)– characterizedby disruption andsubsequentnecrosisofmyofibrilsby hematomaformationinthespaceformedbetweenthe tornmuscleandbyproliferationofinflammatorycells. Step2 repair(fourto21 days)–consistsofphagocytosisof necrotic tissue, regenerationofmyofibrils,and con-comitantproductionofscartissue,aswellasvascular neoformationandnervegrowth.
Step3 remodeling(14daysto14weeks)–periodof matura-tionoftheregeneratedmyofibrils,andreorganization ofthemusclefunctionalcapacity.
Thephysiotherapistneedstounderstandthehealing pro-cessinordertousetheadequatetherapeuticapproachesin theappropriateperiod,sothatrehabilitationcanbeconducted properly.
Rehabilitation
Cryotherapy
Thetraditionaltreatmentinacutemuscleinjuryisdescribed bythePRICEprotocol.33,34Themosteasilyrecognizableeffect
ofcryotherapyisthereductionoftissuetemperature.Infact, virtually all the effects observed in cryotherapy are direct resultsofthechangeintissuetemperature.35Theseeffects
includereducedperfusion,reducedinflammatorysigns(heat, redness,swelling,andpain),andreducedmetabolicrate.7
Itis believed that the mostimportantgoal of cryother-apyisthereductionofmetabolicrateofthecoldtissue.This reductionisbeneficial,asitincreasestheabilityofatissueto survivetheeventsofsecondaryinjuryfollowingtheprimary trauma.Thus,thetotalamount ofinjuredtissueislimited, reducingthetimerequiredtorepairthedamageandreturnto activity.7,36
Theauthorsrecommendcryotherapyfor20minutesevery twohoursduringtheacutestageofmuscularinjuries.37
Therapeuticultrasound(TUS)
TUS is a commonly used resource in musculoskeletal injuries.38AccordingtoBackeretal.,39theacousticvibration
producedbyTUSinducescellularchangesthatchangesthe concentrationgradientofmolecules,aswellascalciumand potassiumions,whichexcitescellularactivity.Thiseventmay result inseveral changes,suchas increase inprotein syn-thesis, secretionof mast cells, fibroblast proliferation, and angiogenesisstimulation,amongothers.
Nonetheless, the effectiveness of TUS in muscle injury repairing process isstillcontroversial.Whilesome authors have observedpositive resultswith use ofTUS,40,41 others
havenot.36,42Somefactors,suchasintensityandfrequency
of treatment with ultrasound, and,moreover, lack of cali-bration ofthe deviceandofaprotocolfordeterminingthe specificdoseforeachindividualcontributetothedivergence ofresults.38
Lowlevellasertherapy(LLLT)
LLLTisalightsourcethatdiffersfrom othersbecause itis monochromatic,coherentintimeandspace,andcollimated, whichallowsforagoodtissuepenetration.43
Thehighincidenceofmuscleinjuryhascausedanincrease in studies related to physical therapy resources that are involved in the injury healing process.44 Among the most
widelyused,LLLTisnoteworthy,asittriggerstheproduction ofadenosinetriphosphate(ATP),45enhancesthemigrationof
satellitecells andfibroblasts,and promotesangiogenesis.46
Theseeffectsareessentialtoachievemoreeffectivemuscle regenerationandpreventtissuefibrosis.9 Theconclusionof
the mostrecentsystematicreviewonthe subjectconfirms thesefindingsandhighlightsthepositiveeffectsofLLLTon musclerepair.47
Manualtherapy
This approach assesses and treats articular, neural, and muscularsystems.Thehandcontactstimulates mechanore-ceptors, which produce afferent impulses and cause neu-romodulations inthecentralnervoussystemtoprovidean analgesicresponseandanimprovementinmuscleandjoint function.48
Cibulkaetal.11hypothesizedarelationshipbetween
ham-stringinjury andpelvichypomobility.Their studyobserved a gain intorque in the flexor muscles as well as a faster returntosportintheexperimentalgroup,whichreceiveda traditionalrehabilitationtreatmentofhamstringinjuries,in additiontojointmanipulationsofthepelvisduringtreatment. Consideringthesefacts,thoseauthorsrecommendadetailed pelvicassessmentinindividualswithhamstringinjury,asthe patientmaybenefitfromjointmobilizations.
Anotherapproachisneuralmobilization,whichisasetof manualtherapytechniquesthatallowforcontrolled mobiliza-tionandstretchingoftheconnectivetissuesurroundingthe nervesandofthenerveitself,whichinturnimprovesnerve conductionanditsintrinsicmobility.49Albeitanuncommon
mobilitydeficitinthesciaticnerve.12Inarecentcasestudy,
AggenandReuteman50reportedthiscomplicationinan
ath-letewho hadsufferedagradeIIIhamstringinjury. Inorder toimproveneuralmobilityandreduceitsmechanical sensi-tivity,neuralglidingtechniqueswereinitiated.Conservative treatmenthasshowntobeeffective.Theauthorssuggestthat neuralglidingtechniquesshouldbeusedincasesofpositive slumptestafterahamstringinjury.
Therapeuticexercises
One of the initial goals of muscle injury rehabilitation is to restore normal neuromuscular control and prevent the formation of tissue fibrosis.6 Therapeutic exercises, such
as isometric strengthening and controlled, pain-free, low-intensityactivemovements,arestrategiesrecommendedby expertstoachievetheseobjectivesatanearlystage.51
In an intermediate phase, an increase in the inten-sityofexercisesisallowed,withneuromusculartrainingat higheramplitudesandtheinitiationofeccentricresistance training.51 Asklinget al.52 demonstratedthe importanceof
eccentricstrengtheninginhamstringinjuries,bycomparinga protocolwithconventionalexercisesandaprotocolbasedon eccentricexerciseswithmaximumdynamicstretching.Their studyconcludedthattheeccentricexerciseprotocolwasmore effective,asitprovidedafasterreturntosportandalower relapserate.Heiderscheitetal.6stressedtheimportanceof
restoringflexibilityatthisstage,inordertopromotebetter ori-entationoffibersduringhealing.Nonetheless,itisimportant torespectpatient’stolerancetostretching.
Inthefinalphaseofrehabilitation,itisrecommendedto increasethe eccentric training and thehigh-speed specific neuromusculartrainingofthesportmovement,in prepara-tion for the return tosport.32,51,53 Sherry et al.4 compared
twointerventionprograms:oneconsistedofspecific stretch-ing exercises and progressivestrengthening of hamstrings andtheothercomprisedprogressiveagilitytrainingand lum-bopelvicstabilization.Theauthorsfoundthattimetoreturnto sportandrecurrenceratewerelowerinthegroupthat under-wentfunctionaltraining,whichdemonstratedtheimportance of agility exercises and of lumbopelvic stabilization dur-ingrehabilitation.Anotherstrategyindicatedtoimprovethe reactive abilityof the neuromuscularsystem isplyometric training,anexercisethatactivatestheeccentric-concentric cycleofthemusculoskeletalsystemandprovidesagainof mechanical,elastic,andmuscularreflexability.54
Return
to
sport
criteria
Thedeterminationofobjective criteriatodefinethe appro-priatetimeforanathletetoresumesportpracticeremains achallengeandanimportantareaforfutureresearch.Based onthebestevidenceavailable,6,55,56athleteswhohavebeen
authorizedtoreturntosportsactivitieswithoutrestrictions shouldbeabletoperformfunctionalskills(running,jumping, dribbling)atfullspeedwithoutpainorstiffnesscomplaints. Flexibilityneedstobesimilartothecontralaterallimb, with-outcomplaints.Regardingstrength,theathleteshouldbeable tocomplete four consecutive repetitions ofmaximal effort
withoutpaincomplaintsinthemanualtestofkneeflexion strength.Ifpossible,isokineticstrengthtestingshouldalsobe performed,underbothconcentricandeccentricaction con-ditions;thepeaktorqueshouldhaveadeficitlowerthan10% whencomparedwiththecontralateralside.
Final
considerations
Hamstring injuriesare common inthe athletic population andhaveahighrecurrencerate.Throughacomplete physi-calevaluationandunderstandingofthemechanismofinjury andriskfactors,arehabilitationspecialistcandeterminethe mostappropriateandindividualizedtreatment.Proper reha-bilitationmustaddressmuscularstrengthdeficits,flexibility, neuromuscularcontrol, lumbopelvicstability, and eccentric strengthening,sincethesehavebeenshowntobeimportant therapeutictargetsforasuccessfulreturnoftheathleteto sports,withlowerriskofrecurrence.Furthermore,LLLThas arisenasanimportantresourceinhelpingtohealtheinjury. Futureresearchshouldincludeevaluationoftheeffectiveness ofcurrentrehabilitationprograms,identificationof appropri-atereturn-to-sportcriteria,andthedevelopmentofeffective preventionstrategiestoreducetheoccurrenceofinjuries.
Conflicts
of
interest
Theauthorsdeclarenoconflictsofinterest.
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