Rev. bras. ortop. vol.49 número2

rev bras ortop.2014;49(2):202–205

w w w . r b o . o r g . b r

Case

Report

Fixation

of

an

osteochondral

fragment

after

acute

patellar

dislocation

in

an

immature

skeleton

夽

,

夽夽

Rodrigo

Pires

e

Albuquerque

,

José

Félix

dos

Santos

Neto

,

Maria

Isabel

Pires

e

Albuquerque

_,

_Vincenzo

_Giordano

_,

_Ney

_Pecegueiro

_do

_Amaral

b_{OrthopedicsService,HospitalMunicipalMiguelCouto,RiodeJaneiro,RJ,Brazil}

c_{InstitutoNacionaldoCâncer,RiodeJaneiro,RJ,Brazil}

a

r

t

i

c

l

e

i

n

f

o

Articlehistory: Received1May2013 Accepted12July2013

Availableonline27March2014

Keywords: Osteochondritis Bonefractures Patella Kneejoint

a

b

s

t

r

a

c

t

Fixationofanosteochondralfractureafteracutepatellardislocationisaninfrequentformof treatment.Likewise,thelocationofthisfragmentinthelateralregionofthelateralfemoral condyle,functioningasafreebody,isuncommon.Theaimofthisstudywastopresenta caseofosteochondralfractureofthepatellaatanunusualsite,alongwiththetherapyused andtheclinicalfollow-up.

©2014SociedadeBrasileiradeOrtopediaeTraumatologia.PublishedbyElsevierEditora Ltda.Allrightsreserved.

Fixac¸ão

do

fragmento

osteocondral

após

luxac¸ão

aguda

da

patela

no

esqueleto

imaturo

Palavras-chave: Osteocondrite Fraturasósseas Patela

Articulac¸ãodojoelho

r

e

s

u

m

o

Afixac¸ãodafraturaosteocondralapósaluxac¸ãoagudadapatelaéumtratamento infre-quente,bemcomoalocalizac¸ãodessefragmentonaregiãolateraldocôndilofemorallateral quefuncionacomoumcorpolivre.Oobjetivodestapesquisafoiapresentarumcasode fraturaosteocondraldapatelaemsítionãousual,assimcomoaterapêuticaadotadaeo seguimentoclínico.

©2014SociedadeBrasileiradeOrtopediaeTraumatologia.PublicadoporElsevierEditora Ltda.Todososdireitosreservados.

夽_{Pleasecitethisarticleas:AlbuquerqueRPe,FélixdosSantosNetoJ,AlbuquerqueMIPe,GiordanoV,PecegueirodoAmaralN.OFixac¸ão}

dofragmentoosteocondralapósluxac¸ãoagudadapatelanoesqueletoimaturo.RevBrasOrtop.2014;49:202–205.

夽夽_{Workperformedatthe“ProfessorNovaMonteiro”OrthopedicsandTraumatologyService,HospitalMunicipalMiguelCouto,Riode}

Janeiro,RJ,Brazil. ∗ _{Correspondingauthor.}

E-mail:rodalbuquerque@ibest.com.br(R.P.e.Albuquerque).

2255-4971/$–seefrontmatter©2014SociedadeBrasileiradeOrtopediaeTraumatologia.PublishedbyElsevierEditoraLtda.Allrightsreserved.

rev bras ortop.2014;49(2):202–205

203

Introduction

Acutedislocationofthepatellainanimmatureskeletonisnot anunusualinjuryintheagegroupbetween13and15years.1 Intra-articularosteochondralfracturesare complications thathavebeenestimatedtooccurinaround5%ofcasesof acutedislocationofthepatellaamongchildren,althoughit shouldbeemphasizedthatitisveryrareforfragmentsofthe patellatofunctionasfreebodiesinthejoint.1

Theaimofthisstudywastopresentacaseoffixationof anosteochondralfragmentsubsequenttoacutedislocation ofthepatella,emphasizingthelocationofthefragmentinan unusualregion,thetherapyusedandtheclinicalfollow-up.

Case

report

Thepatientwasahealthy14-year-oldmalewhosuffered a fallfromastandingpositionthatcauseddirecttraumatothe rightknee,andwastakentotheemergencyserviceofour hos-pital.Thepatient’sconditionevolvedimmediately,withpain, hemarthrosisandincapacitytowalk. Physicalexamination revealededemaintheright kneeand hypermobilityofthe patella,incomparisonwiththecontralateralside.Atthetime ofthetrauma,thepatient’sweightwas60kgandhisheight was1.68m.

Radiographyontherightkneeshowedamarginalfracture ofthepatellawithanosteochondralfragmentlocatedinthe lateralregionofthelateralfemoralcondyle(Fig.1).Computed tomographywasperformedontherightkneetotryto con-firmthediagnosisandmeasurethesizeoftheosteochondral fragment(Fig.1).

Thephysicalexaminationconductedinconjunctionwith theimagingexaminationsconfirmedthediagnosisofacute dislocationofthepatellaand presenceofafreebodyfrom thejoint,locatedinthelateralregionofthelateralfemoral condyle.

Thesurgerywasperformedtwodaysafterhospital admis-sion,usingatourniquetandastraightmedialincisioninthe right knee. The surgicaltechnique used consisted ofopen reductionand osteosynthesis withthree3-mm cannulated

metalscrews intheosteochondralfragmentofthe patella. Themedialpatellofemoralligamentwasrepairedbymeans ofatransosseoussuture(Fig.2AandB).Theosteosynthesis wastestedbymeansofcarefulflexionofthekneejoint.

Aftertheoperation,thekneewasimmobilizedusingalong kneeimmobilizerforsixweeks.Thiswasremovedforactive rehabilitationexercisesinordertoavoidatrophyofthe quadri-ceps.The programconsistedofisometric exercisesfor the quadricepsduringtheimmobilizationperiodandactive exer-cisesforthequadricepswithprogressiveincreasesinrange ofmotion.Completerangeofmotionandafullyfunctioning kneewereachievedinfivemonths.

Ourpatientwasevaluatedoneweek,15days,onemonth, 45daysandtwomonthsaftertheoperationandthenmonthly untilthesixthmonth,whentheconsultationsbecame three-monthly.Wehavenowfollowedupthispatientfortwoyears andhehasreturnedtohishabitualactivitiesaccompaniedby radiologicalcontrols(Fig.3).Inthefunctionalevaluationson theknee,weusedthemodifiedLysholmsystem.2_Weobtained ameanscoreof94pointsintherightknee,whichisconsidered excellentinthisevaluationsystem(Fig.4).

Discussion

Thecasesinthe literaturehavepredominantly occurredin females.1 _{Our case goes against the data inthe literature,} whichemphasizestheimportanceofthepresentcasereport. Webelievethatfemalesaremoreaffectedbecauseofgreater ligament laxity, and also because of hormonal alterations resultingfromthebeginningofthemenstrualcycle.

Themeanageaccordingtotheliteratureis13.3years,and thiswascorroboratedbyourpatient,whowas14yearsofage.1 Hernandezetal.3_{observedthatosteochondralfragments} subsequenttodislocationofthepatellamaygounnoticedon radiographsoftheknee.Wesharedtheirthinkingand,forthis reason,eventhoughwehad madethediagnosis bymeans of radiographs, werequested computed tomography scans inordertounderstandtheinjurybetter.Unfortunately,our servicedoesnothavemagneticresonanceimaging(MRI) avail-able,whichwewouldotherwisehaverequested.Webelieve

204

Fig.2–(AandB)Intraoperativeanalysis.

rev bras ortop.2014;49(2):202–205

205

Fig.4–Postoperativefunctionalevaluation.

thatMRIistheimagingexaminationthatbestassessesthe softtissuesoftheknee.

Nomuraetal.4_{observedintheirseriesthatthemedialfacet} ofthepatella wasthe mostfrequentsite ofosteochondral fractures.However,theydidnotobserveanyfragmentinthe lateralregionofthelateralfemoralcondyle.Forthisreason,we believethatitwasimportantforourrarecasetobepublished. ConradandStanitski5 _{concludedthattreatmentsuccess} dependson early diagnosis ofthe osteochondralfragment andarapidlyimplementedsurgicalapproach.Wecorroborate thisthinkingandemphasizethatawell-performedimaging studyfavorssurgicalplanning.FelusandKowalczyk6_andBitar etal.7_{statedthatthesizeoftheosteochondralfragmentwould} determinewhetherfixationorremovalwastobeperformed. HintonandSharma8_{observedthatosteochondralfragments} generallydonotpresentsufficientsizeforreductionand fixa-tionandnormallyareremoved.Nietosvaaraetal.1_onlyused fixationinthreecasesoftheirsample.Inthislight,ourcaseis relevantbecauseofthegoodfunctionalresultandthetherapy adopted.

Conradand Stanitski5 _{alsoshowedthatmany materials} are available forfixation of osteochondralfragments after acutedislocationofthe patella.Weusedcannulated metal screwsbecausetheseweretheonlyfixationdevicesthatwere availabletousinourhospitalatthatmoment.Kramerand Pace9 _{observedthatinthepediatricpopulation, becauseof} thelackofstudiesorinvestigationswithlong-termfollow-up, itwasnotpossibletostatethatoneimplantwassuperiorto another.

In our opinion, medial arthrotomy was the best surgi-calapproach because of the location of the osteochondral fragment and because of the ability to view the medial patellofemoralligament.KramerandPace9_agreedthat frag-ments of the patella should be dealt with through this access.

Hinton and Sharma8 _{advocated early exercise with} goodguidance,progressivelyimplementedaccordingtothe patient’s level of pain. They reported that through this approach,theatrophyofthequadricepswasdiminishedand thejointcartilagewaskepthealthy.Weagreewiththis think-ing.

Conclusion

Fixationofthe osteochondralfragment ofthe patellaafter acutedislocationusingmetalscrewswasagoodtherapeutic approach.Theunusuallocationofthisfragment,which func-tionedasafreebodyinthejoint,madethisarareinjury.Our patienthasbeenfollowedupfortwoyearssincethe opera-tion,withanexcellentresultaccordingtothescoringsystem used.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

r

e

f

e

r

e

n

c

e

s

1.NietosvaaraY,AaltoK,KallioPE.Acutepatellardislocationin children:incidenceandassociatedosteochondralfractures.J PediatrOrthop.1994;14(4):513–5.

2.TegnerY,LysholmJ.Ratingsystemsintheevaluationofknee ligamentinjuries.ClinOrthopRelatRes.1985;(198):43–9. 3.HernandezAJ,FavaroE,LarayaMH.Luxac¸ãoagudadapatela.

RevBrasOrtop.2004;39(3):65–74.

4.NomuraE,InoueM,KurimuraM.Chondralandosteochondral injuriesassociatedwithacutepatellardislocation.

Arthroscopy.2003;19(7):717–21.

5.ConradJM,StanitskiCL.Adolescentacutepatellardislocation. OperTechSportsMed.2001;9(3):190–3.

6.FelusJ,KowalczykB.Age-relateddifferencesinmedial patellofemoralligamentinjurypatternsintraumaticpatellar dislocation:caseseriesof50surgicallytreatedchildrenand adolescents.AmJSportsMed.2012;40(10):2357–64. 7.BitarAC,D’EliaCO,DemangeMK,ViegasAC,CamanhoGL.

Estudoprospectivorandomizadosobrealuxac¸ãotraumática dapatela:tratamentoconservadorversusreconstruc¸ãodo ligamentofemoropatelarmedialcomtendãopatelar–mínimo dedoisanosdeseguimento.RevBrasOrtop.2011;46(6):675–83. 8.HintonRY,SharmaKM.Acuteandrecurrentpatellarinstability

intheyoungathlete.OrthopClinNorthAm.2003;34(3):385–96. 9.KramerDE,PaceJL.Acutetraumaticandsports-related