Chondromalacia PatellaePatellaCartilage DiseasesJoint DiseasesFlatfootKnee JointCartilage, ArticularCollateral LigamentsTracheobronchomalaciaArthroplasty, SubchondralBaseballArthroscopyFemurKnee InjuriesJoint InstabilityIntegrin-Binding SialoproteinPatellar LigamentPatellofemoral JointPatellar DislocationNail-Patella SyndromeDislocationsKnee ProsthesisArthroplasty, Replacement, KneeProchloronOsteoarthritis, KneeTibiaRange of Motion, ArticularPatellofemoral Pain SyndromeArthralgiaOsteochondritis