PatellaChondromalacia PatellaePatellar LigamentCartilage DiseasesPatellofemoral JointPatellar DislocationKnee JointNail-Patella SyndromeDislocationsCartilage, ArticularArthroplasty, Replacement, KneeKnee ProsthesisOsteoarthritis, KneeProchloronJoint InstabilityFemurRange of Motion, ArticularArthralgiaTreatment OutcomeTibiaPatellofemoral Pain SyndromeOsteochondritisKnee InjuriesFollow-Up StudiesMagnetic Resonance ImagingQuestionnairesQuadriceps MuscleBone WiresRetrospective StudiesJoint DiseasesKneeBiomechanical PhenomenaMolluscaLeadAnatomic LandmarksPainTime FactorsDepressionProspective StudiesCadaverSymptom AssessmentSeverity of Illness IndexTendonsPain MeasurementBone MalalignmentArthroscopyBone Diseases, DevelopmentalCross-Sectional StudiesReoperationRisk Factors