简介：Non-lineardynamics,fractals,periodicoscillations,bifurcations,chaos,andotherterminologieshavebeenusedtodescribehumanbiologicalsystemsintheliteratureforafewdecades.Theeightmanuscriptsincludedinthisspecialissuediscussedthehistoricalbackground,selectedtheoretical

简介：Background:Preventinganteriorcruciateligament(ACL)injuriesisveryimportantforathletes,anddynamickneevalgusisconsideredariskfactorfornon-contactACLinjury.However,littleisknownaboutwhetherthefunctionsofthehipabductorandrear-footincreasedynamickneevalgus.Atwo-dimensional(2D)video-basedscreeningtestfocusedonhipabductorandrear-footfunctionsamongfactorsinvolvedindynamickneevalgus.Thepresentstudydeterminedassociationsbetweenhipandrear-footdynamicalignmentanddynamickneevalgus.Methods:Thiscross-sectionalstudyrecruited130femalebasketballplayers(258legs)fromninehigh-schoolteams.Theplayersperformedsingle-legsquatsandsingle-legdroplandingstoprovideknee-in(KID)andhip-out(HOD)distanceson2Dvideoimages.Hipandrear-footdynamicalignmentwasevaluatedusingadynamicTrendelenburgtest(DTT)andadynamicheel-floortest(HFT).Results:TheChi-squaretestrevealednosignificantdifferenceintheprevalenceofDTT-positivitybetweensingle-legsquats(28.7%)andsinglelegdroplandings(23.3%).TheprevalenceofHFT-positivitywassignificantlygreaterduringlandings(51.4%)thanduringsingle-legsquats(31.0%,p<0.01).TheKIDvaluesforbothsingle-legsquatsandsingle-legdroplandingsweregreaterintheDTT-positivethanintheDTTnegativegroup(15.15.4cmand20.27.5cm,p<0.001).TheHODvaluesweresimilarlygreaterintheDTT-positivegroup(15.21.9cmand17.62.8cm,p<0.001).TheKIDvaluesforbothsingle-legsquatsandsingle-legdroplandingsweregreaterintheHFT-positivethanintheHFT-negativegroup(12.25.1cm,p<0.01;14.77.2cm,p<0.001),whereasHODvaluesforthesetasksdidnotsignificantlydifferbetweenthetwogroups.Conclusion:Dynamichipmal-alignmentmightbeassociatedwithbothgreaterKIDandHOD,whereasrear-footeversionisassociatedonlywithgreaterKID.Hipabductorandrear-footdysfunctionareimportantfactorsfordynamickneevalgusandthusevaluatingDTTandHFTwi

简介：<正>Background:Stochasticresonancestimulation(SRS)transmitssubsensoryelectricalGaussianwhitenoiseintothebodytoenhancesensorimotorfunction.Thistherapyhasimprovedstaticsinglelegbalanceinsubjectswithfunctionalankleinstability.However,theeffectofthisstimulationondynamicsinglelegbalanceisnotknown.ImprovementsindynamicsinglelegbalancewithSRSmayhaveimplicationsForenhancingfunctionalrehabilitationforankleinstability.Thus,thepurposeofthisstudywastodeterminetheeffectsofSRSondynamicsinglelegbalanceinsubjectswithfunctionalankleinstability.Methods:Thisstudywasanexperimentalresearchdesignanddatawerecollectedinasportsmedicineresearchlaboratory.Twelvesubjectswithfunctionalankleinstability(69±15kg;173±10cm;21±2years)reportedahistoryofanklesprainsandinstabilityattheanklewithphysicalactivity.Asinglelegjump-landingtestwasusedtoassessdynamicbalance.Subjectswererequiredtojumpbetween50%and55%ofthemaximalverticaljumpheight,landonasinglelegatopaforceplate,andstabilizeasquicklyaspossible.Jump-landingtestswereperformedwithandwithoutSRS.Threetrialswereperformedforeachtreatmentcondition(SRSandcontrol).Arandomizedblockdesignwasusedtodeterminetestorder.Anterior/posteriorandmedial/lateraltime-to-stabilizationwerecomputedtoassessdynamicbalance.Lessertimeindicatedbetterstability.One-tailedpairedsamplesttestswereusedforanalysis(α≤0.05).Results:SRSimprovedanterior/posteriortime-to-stabilization(stochasticresonance=1.32±0.31s,control=1.74±0.80s,p=0.03),butdidnotenhancemedial/lateraltime-to-stabilization(stochasticresonance=1.95±0.40s,control=1.92±0.48s,p=0.07).Conclusion:CliniciansmightuseSRStofacilitatebalanceimprovementswithsagittalplanedynamicsinglelegbalanceexercisesthatpatientsmaynotbeabletoperformotherwise.