Lasegue sign or straight leg raising test (SLRT) is a neurodynamic exam to assess nerve root irritation in the lumbosacral area.[1] It is an ...NCBISkiptomaincontentSkiptonavigationResourcesHowToAboutNCBIAccesskeysMyNCBISignintoNCBISignOutNCBIBookshelf.AserviceoftheNationalLibraryofMedicine,NationalInstitutesofHealth.StatPearls[Internet].TreasureIsland(FL):StatPearlsPublishing;2021Jan-.StatPearls[Internet].ShowdetailsTreasureIsland(FL):StatPearlsPublishing;2021Jan-.SearchtermLasegueSignJoeMDas;MustafaNadi.AuthorInformationAuthorsJoeMDas1;MustafaNadi2.Affiliations1BirminghamChildren'sHospital,SteelhouseLn,BirminghamB46NH2DalhousieLastUpdate:March31,2021.Definition/IntroductionLaseguesignorstraightlegraisingtest(SLRT)isaneurodynamicexamtoassessnerverootirritationinthelumbosacralarea.[1] Itisanintegralelementtotheneurologicalexamforpatientspresentingwithlowbackpainwithorwithoutradicularpain.TheotherlesscommonlyusednameisLazarevicsign.HistoricalEvolutionTraditionally,Ernest-CharlesLasegue(1816-1883)isconsideredthefirstphysicianwhoverballydescribedthissignandemphasizeditsimportanceinpatientswithsciatica.[2] Albeit,hedidnotwriteitinhispublications.[3]PublicationofthesignwasbyoneofLasegue'sstudents,JJForst,whodescribeditinhisdoctoralthesistitled Contribuition al’etudeCliniquedelaSciatique in1881.BothLasegueandForstproposedthatthesharppainelicitedbythetestwasduetocompressionofthesciaticnervebymuscularcontraction.[2] Historically,Lazarevic(1851-1891)wasthefirstphysicianwhopublishedthissignin1880withasoundpathophysiologicalexplanation.[2] Thelattersuggestedsciaticnervestretchingasthecauseofpainwhiledoingthetest.HisexplanationhadbackingbyLuciendeBeurmanncadavericexperimentin1884.[2][4] SeveralmodificationswereintroducedtoSLRT,anddifferentmethodswereimplementedtoprovokepaininirritatednerveroots.ThesemodificationsintendedtoimproveSLRTaccuracyandsomeothertestscouldbecomplementary.[5][6] Ofnote,althoughthereisnogeneralagreementoninterpretingtheresultsofSLRTanditsvariants[7], perfo