ObjectiveA-T　flap　has　been　extensively　applied　to　repair　dermal　soft　tissue　defects.　The　flap　design　completely　depends　on　the　experience　of　doctors.　Herein,　we　explored　the　approach　of　analyzing　the　reasonability　of　A-T　flap　design　and　performed　a　simulation　of　operation　processes　by　computer-aided　technology.　Afterward,　the　finite　element　analysis　software　(MSC.Marc/Mentat)　was　used　to　establish　the　simulation　model,　based　on　which　the　computer　simulation　of　flap　suturing　and　release　state　in　A-T　flap　surgery　was　performed.　MethodsA　geometrical　model　of　the　A-T　flap　was　established,　and　the　length-width　ratio　of　the　flap,　maximum　suture　distance,　and　suture　area　that　could　influence　the　postoperative　suture　effects　of　the　flap　were　analyzed.　The　reasonable　surgical　planning　for　A-T　flap　design　based　on　the　crossing　constraint　relationship　was　achieved.　The　simulation　model　was　established　by　the　finite　element　analysis　software　(MSC.Marc/Mentat),　based　on　which　computer　simulation　of　flap　suture　and　release　state　of　A-T　flap　in　surgery　processes　were　performed.　The　flap＇s　stress　and　deformation　distribution　results　confirmed　the　applicability　of　the　A-T　flap　design　method　proposed　in　the　present　study.　ResultsWhen　the　apex　angle　of　the　A-T　flap　was　60　degrees,　the　suture　area　was　the　smallest,　and　the　flap　design　had　the　highest　practicability.　ConclusionComputer-assisted　preoperative　assessment,　which　has　high　clinical　value,　could　provide　a　theoretical　basis　for　A-T　flap　design　in　clinical　practice.