w w w . r b o . o r g . b r
Original
Article
Reconstruction
of
the
medial
patellofemoral
ligament
in
cases
of
acute
traumatic
dislocation
of
the
patella:
current
perspectives
and
trends
in
Brazil
夽
,
夽夽
Gustavo
Gonc¸alves
Arliani
a,∗,
Adriano
Vaso
Rodrigues
da
Silva
b,
Léo
Renato
Shigueru
Ueda
b,
Diego
da
Costa
Astur
a,
João
Alberto
Yazigi
Júnior
b,
Moises
Cohen
baSportsTraumatologyCenter,DepartamentofOrthopedicsandTraumatology,UniversidadeFederaldeSãoPaulo(UNIFESP),SãoPaulo,
SP,Brazil
bDepartamentofOrthopedicsandTraumatology,UniversidadeFederaldeSãoPaulo(UNIFESP),SãoPaulo,SP,Brazil
a
r
t
i
c
l
e
i
n
f
o
Articlehistory: Received20June2013 Accepted23August2013 Availableonline29July2014
Keywords: Knee Kneejoint
Medialpatellofemoralligament Reconstruction
Rehabilitation
a
b
s
t
r
a
c
t
Objective:ToevaluatetheapproachesandproceduresusedbykneesurgeonsinBrazilfor treatingmedialpatellofemorallesions(MPFL)ofthekneeincasesofacutetraumatic dislo-cationofthepatella.
Materialsandmethods:Aquestionnairecomprising15closedquestionsontopicsrelating totreatingMPFLofthekneefollowingacutedislocationofthepatellawasused.Itwas appliedtoBraziliankneesurgeonsduringthethreedaysofthe44thBrazilianCongressof OrthopedicsandTraumatology,in2012.
Results:106kneesurgeonscompletelyfilledoutthequestionnaireandformedpartofthe sampleanalyzed.MostofthemwerefromthesoutheasternregionofBrazil.Themajority (57%)reportedthattheyperformfewerthanfiveMPFLreconstructionproceduresperyear. Indicationofnon-surgicaltreatmentafterafirstepisodeofacutedislocationofthepatella waspreferredanddoneby93.4%ofthesample.Only9.1%oftheparticipantsreportedthat theyhadneverobservedpostoperativecomplications.Intraoperativeradioscopywasused routinelyby48%.Theprofessionalswhodidnotusethistooltodeterminethepointof ligamentfixationinthefemurdidnothaveastatisticallygreaternumberofpostoperative complicationsthanthosewhousedit(p>0.05).
Conclusions: Thereareclearevolutionarytrendsintreatmentsandrehabilitationforacute dislocationofthepatelladuetoMPFL,inBrazil.However,furtherprospectivecontrolled studiesareneededinordertoevaluatetheclinicalandscientificbenefitofthesetrends.
©2014SociedadeBrasileiradeOrtopediaeTraumatologia.PublishedbyElsevierEditora Ltda.Allrightsreserved.
夽
Please cite this article as: Arliani GG, da Silva AVR, Ueda LRS, Astur DC, Yazigi Júnior JA, Cohen M. Reconstruc¸ão do liga-mentopatelofemoral medial na luxac¸ãotraumática aguda da patela:perspectivas e tendências atuaisno Brasil. RevBras Ortop. 2014;49(5):499–506.
夽夽
WorkdevelopedattheSportsTraumatologyCenter,DepartmentofOrthopedicsandTraumatology,UniversidadeFederaldeSãoPaulo, SãoPaulo,SP,Brazil.
∗ Correspondingauthor.
E-mail:ggarliani@hotmail.com(G.G.Arliani).
http://dx.doi.org/10.1016/j.rboe.2014.07.005
Reconstruc¸ão
do
ligamento
patelofemoral
medial
na
luxac¸ão
traumática
aguda
da
patela:
perspectivas
e
tendências
atuais
no
Brasil
Palavras-chave: Joelho
Articulac¸ãodojoelho
Ligamentopatelofemoralmedial Reconstruc¸ão
Reabilitac¸ão
r
e
s
u
m
o
Objetivo: AvaliarascondutaseosprocedimentosfeitospeloscirurgiõesdejoelhodoBrasil notratamentodaslesõesdoligamentopatelofemoralmedial(LPFM)dojoelhonaluxac¸ão agudatraumáticadapatela.
Materiaisemétodos:Questionáriode15questõesfechadasqueabordavatópicosrelacionados aotratamentodaslesõesdoLPFMdojoelhoapósluxac¸ãoagudadapatela.Foiaplicadoa cirurgiõesbrasileirosdejoelhoduranteostrêsdiasdo44◦CongressoBrasileirodeOrtopedia
eTraumatologia,em2012.
Resultados: Preencheramcompletamenteoquestionárioefizerampartedaamostra anal-isada 106 cirurgiões de joelho. A maior parte era proveniente da Região Sudeste. A maioria(57%)relatoufazermenosdecincoprocedimentosdereconstruc¸ãodoLPFM/ano.A indicac¸ãodotratamentonãocirúrgicoapósprimeiroepisódiodeluxac¸ãoagudadapatelaé apreferidaefeitapor93,4%daamostra.Somente9,1%dosparticipantesrelataramnunca ter observado complicac¸õesno pós-operatório.Aradioscopia intraoperatóriaé adotada rotineiramentepor 48%.Osprofissionaisquenãoausamparadeterminac¸ãodoponto defixac¸ãodoligamentonofêmurnãoobservamestatisticamentemaiscomplicac¸ões pós-operatóriascomparadoscomosqueusamessaferramenta(p>0,05).
Conclusões: Existem claras tendências deevoluc¸ãono tratamento ena reabilitac¸ão da luxac¸ãoagudadapatelacomlesãodoLPFMnoBrasil.Noentanto,maisestudosprospectivos controladossãonecessáriosparaavaliarobenefícioclínicoecientíficodessastendências.
©2014SociedadeBrasileiradeOrtopediaeTraumatologia.PublicadoporElsevier EditoraLtda.Todososdireitosreservados.
Introduction
Acutedislocationofthepatellaisaninjurytypicalofyoung andactivepatientsofbothsexes.Theprevalenceinthe pop-ulationis6–77casesper100,000inhabitants.1,2 Theoverall recurrencerateafterafirstepisodeiscloseto40%.3
Normalfunctioningofthefemoropatellarjointisassured throughstaticanddynamicstabilizers.However,overrecent years, there has been growing interest in the orthopedic literatureinstudyingtheligamentstructuresthataidin sta-bilizationofthepatella.4,5
Amongthesestructures,theonethathasbeenmost stud-iedis certainlythe medialpatellofemoralligament (MPFL). This extends from the medialand superior margin ofthe patellatothefemur,whereitisinsertedbetweenthe adduc-tortubercleandthemedialepicondyle.Itisresponsiblefor 50–60%ofthelateralrestrictionstrengthofthepatella.6,7
TheMPFLisoftendamagedafterepisodesofpatellar dislo-cation,andmanydifferentsurgicalreconstructiontechniques havenowbeendescribedintheliterature.3
Overrecentyears,severalstudieshavebeenconductedon thissubject.5,8,9 However,thereisstillno consensusinthe literature,regardingavarietyofissues.3
Thehighincidenceoftheseinjuriesandthegreat impor-tanceofsocialandeconomicfactorsrelatingtothem,along withtheenormousdivergencesintheliteratureonthis sub-ject,makeitextremelyrelevanttoevaluatemanagementand trendsrelatingtothistopic.
Theaimofthis study wastoevaluatethemanagement andproceduresimplementedbykneesurgeonsinBrazil,in
treatingacuteinjuriesoftheMPFL.Fromtheresultsofthis study,wewouldbeabletodelineatenationaltrendsrelating tothissubjectandguidefuturequalitystudies.
Materials
and
methods
Thiswasadescriptivestudyconsistingofapplyinga question-nairetoasampleofkneesurgeonsinBrazil.Thequestionnaire wasdrawnupandapprovedbytheauthorsinsuchawaythat itwouldbeveryeasytounderstandandsimple.Itconsisted of 15 closed questions that addressed topics like the sur-geons’numberofyearsofexperienceandnumberofMPFL reconstructions performedper yearand avarietyofissues relatingtoindicationsandtreatmentsusingthesemethods (Annex1).
ThequestionnairewasappliedtoBraziliankneesurgeons duringthethreedaysofthe44thBrazilianCongressof Ortho-pedics and Traumatology, in 2012. Only orthopedists who performedkneesurgeryfilledoutthequestionnaire.Atotalof 116questionnaireswerefilledout.Ofthese,tenwereexcluded becausetheyhadnotbeenfilledout completely.Toresolve anydoubtswhilesubjectswerefillingoutthequestionnaire, three researchers were present throughout the application period.
Fromthedataextractedfromthequestionnaires, descrip-tive statistics on the variables involved were produced,in ordertocharacterizethesample.
Table1–DescriptionofthelengthofexperienceofMPFLsurgeryprofessionalsaccordingtoeachcharacteristicof interestandtheresultsfromthecomparisons.
Variable No Yes v
Mean SD N Mean SD N
1/3Medialpatellartendon 5.66 6.01 89 7.93 6.18 14 0.195
1/3Medialquadricepstendon 5.74 6.09 87 7.25 5.86 16 0.360
Gracilisandsemitendinosusflexortendons 5.34 5.38 76 7.74 7.49 27 0.077
DirectrepairofMPFL(arthroscopicor open)
5.86 6.10 96 7.43 5.59 7 0.512
Gracilisflexortendon 5.94 6.20 84 6.11 5.54 19 0.915
Semitendinosusflexortendon 5.90 5.74 69 6.12 6.74 34 0.864
Other 6.22 6.14 97 2.00 1.67 6 0.098
Femur
Endobutton 6.02 6.12 96 5.29 5.50 7 0.758
Interference/Biotenodesisscrew 5.03 5.99 33 6.41 6.08 70 0.281
Anchors 6.00 6.03 93 5.7 6.57 10 0.882
Screw(Post) 6.12 6.16 98 3.00 2.00 5 0.263
Clips(AGRAF) 5.97 6.05 103 0 a
Directsuturing 5.93 5.85 91 6.25 7.71 12 0.866
Others 5.97 6.05 103 0 a
Patella
Endobutton 5.82 6.01 93 7.40 6.57 10 0.435
Interference/Biotenodesisscrew 5.94 6.15 94 6.33 5.20 9 0.852
Anchors 5.71 5.72 75 6.68 6.93 28 0.471
Screw(Post) 5.97 6.05 103 0 a
Clips(AGRAF) 5.97 6.05 103 0 a
Directsuturing 5.66 5.70 86 7.53 7.61 17 0.247
Others 6.17 6.24 94 3.89 3.02 9 0.282
Surgicaltreatmentindicatedafter firstepisodeofpatellardislocation
5.65 5.85 96 12.00 6.93 6 0.012
Useofintraoperativeradioscopyto determinefixationpointforfemoral “neoligament”
6.35 6.43 52 5.81 5.76 48 0.664
ResultfromStudentttest.
a Notpossibletocalculatetheabsenceofprofessionalswhoperformtheprocedure.
Results
The questionnaire was completely filled out by 106 sur-geons,and thesesubjects comprisedthe sampleanalyzed. Themajorityofthesurgeons(56.6%)were from the south-easternregion.Regardingtheirlengthofexperience,themean obtainedwas5.97years(±6.054),withaminimumofoneyear andmaximumof30years.Themajorityoftheparticipants (57%)reporteddoingfewerthanfiveMPFLreconstruction pro-ceduresperyear.Thetypesofgraftmostusedwerethetendon ofthesemitendinosusmuscle,by36%,andbothoftheflexor tendons(gracilisandsemitendinosus),by28%.Theoptionof graftfixationatkneeflexionof30◦or45◦waschosenbythe
greatestproportionofthe sample(75%);50% ofthe partic-ipantsperformedthefixationwiththe kneesflexedat30◦.
Inrelationtothegraftfixationmethod,themajorityusedan interference/Biotenodesisscrew(70%)forgraftfixationtothe femurandanchors(28%)forfixationtothepatella.Indication ofnon-surgicaltreatmentafterafirstepisodeofacute disloca-tionofthepatellawaspreferredandwasdoneby93.4%ofthe sample.Preoperativeevaluationwithcomplementary exam-inations before performing MPFL reconstruction was done by98.1%.Aperiodofonetofour weeksbetweentheacute
dislocationofthepatellaandthesurgicalprocedurewas con-sideredidealbythelargestnumberoftheparticipants(31.6%). Intraoperative radioscopy was performedroutinely by48%. Themajority(60.8%)hadaspecificpostoperative rehabilita-tionprotocol.Regardingbracesforimmobilizationduringthe postoperativeperiod,70.3%usedthem.Thelargest number ofthosewhousedimmobilizationaftersurgerydidsoforup tooneweek(30.7%).Failureofconservativetreatment(86.9%) andpresenceoffactorspredisposingtowardpatellar instabil-ity(63.3%)werethefactorsthatwereconsideredtobemost determinantinmakingadecisiontooperateonapatient.Pain (75.8%)andkneejointeffusion(33.3%)werethecomplications mostobservedduringthepostoperativeperiod.Only9.1%of the surgeonsreportedneverhavingobservedpostoperative complications.Table1showsthat,onaverage,the profession-alswhoindicatedsurgicaltreatmentafterafirstepisodeof patellardislocationhadhadstatisticallysignificantlylonger experienceofMPFLreconstructionsurgery(p=0.012).Table2
showsthatthetimeintervalbetweentheinjury/dislocation andthesurgerythattheprofessionalsjudgedtobeidealdid nothaveanystatisticallysignificantinfluenceonthetypes andfrequenciesofcomplicationsobserved(p>0.05).Table3
Table2–Descriptionofthetimeintervalbetweeninjury/dislocationandsurgerythatwasjudgedtobeideal,according tothecomplicationsobservedandtheresultsfromthecomparativetests.
Complicationsobserved postoperatively
Timeintervalbetweeninjury/dislocationandsurgerythatwasjudgedtobeideal Total p
Upto7days 1–4weeks 4–12weeks 12–24weeks 6–12months >1year
N % N % N % N % N % N %
Pain 0.590
No 3 12.5 8 33.3 4 16.7 1 4.2 7 29.2 1 4.2 24
Yes 2 2.8 23 32.4 16 22.5 13 18.3 15 21.1 2 2.8 71
Quadricepsdysfunction 0.146
No 5 7.6 22 33.3 15 22.7 9 13.6 13 19.7 2 3.0 66
Yes 0 0.0 9 31.0 5 17.2 5 17.2 9 31.0 1 3.4 29
Presenceofgrip 0.701
No 5 5.5 29 31.9 19 20.9 14 15.4 21 23.1 3 3.3 91
Yes 0 0.0 2 50.0 1 25.0 0 0.0 1 25.0 0 0.0 4
Diminishedkneerangeof motion
0.762
No 5 7.5 19 28.4 16 23.9 12 17.9 12 17.9 3 4.5 67
Yes 0 0.0 12 42.9 4 14.3 2 7.1 10 35.7 0 0.0 28
Lateralpatellar subluxation/dislocation
0.274
No 5 6.1 29 35.4 15 18.3 11 13.4 20 24.4 2 2.4 82
Yes 0 0.0 2 15.4 5 38.5 3 23.1 2 15.4 1 7.7 13
Medialpatellar subluxation/dislocation
0.854
No 3 3.4 31 35.2 20 22.7 9 10.2 22 25.0 3 3.4 88
Yes 2 28.6 0 0.0 0 0.0 5 71.4 0 0.0 0 0.0 7
Patellarfracture 0.298
No 5 5.6 31 34.4 19 21.1 10 11.1 22 24.4 3 3.3 90
Yes 0 0.0 0 0.0 1 20.0 4 80.0 0 0.0 0 0.0 5
Kneejointeffusion 0.760
No 3 4.6 23 35.4 12 18.5 10 15.4 16 24.6 1 1.5 65
Yes 2 6.7 8 26.7 8 26.7 4 13.3 6 20.0 2 6.7 30
Infection 0.217
No 5 5.4 31 33.7 19 20.7 13 14.1 22 23.9 2 2.2 92
Yes 0 0.0 0 0.0 1 33.3 1 33.3 0 0.0 1 33.3 3
Withoutcomplications 0.238
No 3 3.5 28 32.6 19 22.1 13 15.1 20 23.3 3 3.5 86
Yes 2 22.2 3 33.3 1 11.1 1 11.1 2 22.2 0 0.0 9
ResultsfromMann–Whitneytest.
observestatisticallygreaternumbersofpostoperative compli-cationsthanwerenotedbythosewhousedthisintraoperative tool(p>0.05).
Discussion
Severalstudiesontreatmentofacutedislocationofthepatella andMPFLreconstructionwerefound,butnoneofthemhad theaimofevaluatingtheperspectivesandtrendsintreating andrehabilitatingpatientswithinjuriestothisligamentafter traumaticdislocation.Studieshaverecentlybeenconducted inBrazil,butwiththeaimofevaluatingthetreatment meth-odsusedincasesoflateral anklesprains,anteriorcruciate ligamentinjuriesandunicompartmentalkneearthrosis.10–12 In evaluating the regional frequencies of participating
Table3–Descriptionofthepresenceofcomplicationsaccordingtouseofintraoperativeradioscopyfordeterminingthe fixationpointfortheneoligamentinthefemurandtheresultsfromtheassociationtests.
Complicationsobservedpostoperatively Useofintraoperativeradioscopytodeterminethe fixationpointoftheneoligamentinthefemur
Total p
No Yes
N % N %
Pain 0.680
No 13 26.0 11 22.4 24
Yes 37 74.0 38 77.6 75
Quadricepsdysfunction 0.099
No 30 60.0 37 75.5 67
Yes 20 40.0 12 24.5 32
Presenceofgrip 0.678a
No 46 92.0 47 95.9 93
Yes 4 8.0 2 4.1 6
Diminishedkneerangeofmotion 0.213
No 32 64.0 37 75.5 69
Yes 18 36.0 12 24.5 30
Lateralpatellarsubluxation/dislocation 0.076
No 46 92.0 39 79.6 85
Yes 4 8.0 10 20.4 14
Medialpatellarsubluxation/dislocation 0.160a
No 48 96.0 43 87.8 91
Yes 2 4.0 6 12.2 8
Patellarfracture 0.027a
No 50 100.0 44 89.8 94
Yes 0 0.0 5 10.2 5
Kneejointeffusion 0.477
No 35 70.0 31 63.3 66
Yes 15 30.0 18 36.7 33
Infection >0.999a
No 47 94.0 47 95.9 94
Yes 3 6.0 2 4.1 5
Withoutcomplications 0.741a
No 46 92.0 44 89.8 90
Yes 4 8.0 5 10.2 9
ResultsfromChi-squaretest. a ResultsfromFisher’sexacttest.
patella.Arecentstudydemonstratedthatfixationwith inter-ferencescrewswasjustasstrongasthetechniqueofusing transversetunnelsinthepatella,forMPFLreconstruction.14 Anotherstudy demonstrated that graftfixation using tran-sosseoussuturesinthe patellaprovidedloadingsimilar to failure,but lower rigiditythan withfixationusinganchors, interferencescrewsortransversaltunnels.9Indicationof non-surgical treatment after a first episode ofacute traumatic dislocationofthepatellawaspreferredinourstudy(93.4%). Thereisstillnoconsensusregardingthismatterinthe litera-ture.However,moststudieshaverecommendedconservative treatmentafterafirstepisodeoftraumaticpatellar disloca-tion,intheabsenceofosteochondrallesionsandsignificant riskfactorsforrecurrence.Thesestudiesdidnotshowany dif-ferencebetweensurgicalandnon-surgicaltreatmentsaftera firstepisodeofacutepatellardislocation.15,16 However,Bitar etal.demonstratedthatMPFLreconstructionusingthe patel-lartendonproduced betterresults,based onthe incidence
wedidnotfindthatthetimeintervaluntilthesurgeryanduse ofintraoperativeradioscopyshowedanycorrelationwiththe complicationsobservedafterthesurgery.However,previous studieshaveshownthataroundhalfofthecomplicationsare consequenttotechnicalerrorssuchaspoorpositioningofthe femoraltunnel.20
Conclusion
This study demonstrated that there are clear evolutionary trendsintreatingandrehabilitatingcasesofacutedislocation ofthepatellawithMPFLinjury.However,furthercontrolled
prospectivestudiesareneededinordertoevaluatetheclinical andscientificbenefitofthesetrends.
Conflicts
of
interest
Theauthorsdeclarenoconflictsofinterest.
Annex
1.
Knee
MPFL
surgery
and
rehabilitation
r
e
f
e
r
e
n
c
e
s
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