简介：<正>Background:Significanteffortshavebeenmadetoidentifymodifiableriskfactorsofnon-contactanteriorcruciateligament(ACL)injuriesinmaleandfemaleathletes.However,currentliteratureontheriskfactorsforACLinjuryarepurelydescriptive.Anunderstandingofbiomechanicalrelationshipbetweenriskandriskfactorsofthenon-contactACLinjuryisnecessarytodevelopeffectivepreventionprograms.Purpose:Tocomparelowerextremitykinematicsandkineticsbetweentrialswithandwithoutnon-contactACLinjuriesandtodetermineifanydifferenceexistsbetweenmaleandfemaletrialswithnon-contactACLinjuriesregardingthelowerextremitymotionpatterns.Methods:Inthiscomputersimulationstudy,astochasticbiomechanicalmodelwasusedtoestimatetheACLloadingatthetimeofpeakposteriorgroundreactionforce(GRF)duringlandingofthestop-jumptask.MonteCarlosimulationswereperformedtosimulatetheACLinjurieswithrepeatedrandomsamplesofindependentvariables.Thedistributionsofindependentvariablesweredeterminedfrominvivolaboratorydataof40maleand40femalerecreationalathletes.Results:Inthesimulatedinjuredtrials,bothmaleandfemaleathleteshadsignificantlysmallerkneeflexionangles,greaternormalizedpeakposteriorandverticalGRF.greaterkneevalgusmoment,greaterpatellatendonforce,greaterquadricepsforce,greaterkneeextensionmoment.andgreaterproximaltibiaanteriorshearforceincomparisontothesimulateduninjuredtrials.Nosignificantdifferencewasfoundbetweengendersinanyoftheselectedbiomechanicalvariablesinthetrialswithsimulatednon-contactACLinjuries.Conclusion:Smallkneeflexionangle,largeposteriorGRF.andlargekneevalgusmomentareriskfactorsofnon-contactACLinjurydeterminedbyastochasticbiomechanicalmodelwithacause-and-effectrelationship.