This　paper　introduces　an　efficient　contact-based　registration　method　for　minimally　invasive　anterior　hip　arthroplasty.　Unlike　existing　methods　that　involve　radiation　exposure,　implanted　screws,　or　tedious　point　collection,　our　method　requires　only　one　contact　within　the　acetabulum　and　two　contacts　on　the　landmarks.　Inspired　by　the　probe＇s　ball　tip,　we　define　a　unique　position,　named　stable　point,　to　decouple　translation　from　the　overall　transformation.　The　stable　point　in　patient　space　is　easily　acquired　by　our　tool,　simplifying　translation　estimation　to　compute　the　stable　point　in　image　space.　We　present　a　fast　computation　method　based　on　dichotomic　search.　After　aligning　the　stable　points,　we　introduce　two　bone　landmarks　for　rotation　estimation　in　a　center-aware　manner.　Additionally,　a　deltille　grid　position-sensing　(DGPS)　marker　is　used　to　improve　instrument　tracking　robustness.　Experiments　were　conducted　to　evaluate　the　performance　of　our　methods,　demonstrating　an　average　accuracy　of　0.16±0.03mm　for　instrument　tracking　and　1.41±0.16mm　for　registration.　Moreover,　the　entire　process　takes　less　than　1　minute.　Results　suggest　that　our　method　has　significant　potential　for　clinical　application.　©　2024