Arthritis, PsoriaticArthritisArthritis, RheumatoidPsoriasisArthritis, ExperimentalAntirheumatic AgentsArthritis, InfectiousSpondylitis, AnkylosingJointsArthritis, JuvenileArthritis, ReactiveSynovial MembraneNail DiseasesSynovial FluidHand JointsRheumatic DiseasesSeverity of Illness IndexSynovitisSpondylitisToe JointSpondylarthropathiesReceptors, Tumor Necrosis FactorRheumatoid FactorSpondylarthritisFinger JointFoot JointsPeriostitisTumor Necrosis Factor-alphaDermatologic AgentsArthrographyMethotrexateAntibodies, MonoclonalBlood SedimentationOsteoarthritisHLA-C AntigensImmunoglobulin GAntibodies, Monoclonal, HumanizedTreatment OutcomeSacroiliac JointHLA-B27 AntigenRheumatologyIritisGenetic Predisposition to DiseaseDouble-Blind MethodKnee JointEtretinateAnti-Inflammatory AgentsHLA-B39 AntigenDisability Evaluation