Arthritis, PsoriaticArthritis, RheumatoidArthritisPsoriasisArthritis, ExperimentalArthritis, InfectiousInflammationArthritis, JuvenileArthritis, ReactiveJointsAntirheumatic AgentsSynovial MembraneSpondylitis, AnkylosingSynovial FluidSynovitisSeverity of Illness IndexNail DiseasesRheumatic DiseasesHand JointsRheumatoid FactorTumor Necrosis Factor-alphaReceptors, Tumor Necrosis FactorOsteoarthritisSpondylarthropathiesSpondylitisToe JointMethotrexateBlood SedimentationArthrographyFinger JointAntibodies, MonoclonalFoot JointsImmunoglobulin GSpondylarthritisTreatment OutcomeDermatologic AgentsInflammation MediatorsPeriostitisArthritis, GoutyAnti-Inflammatory AgentsHLA-C AntigensAntibodies, Monoclonal, HumanizedRheumatologyMice, Inbred DBABiological MarkersSacroiliac JointHLA-B27 AntigenGenetic Predisposition to DiseaseCytokinesAutoantibodiesKnee JointInjections, Intra-ArticularDisease Models, AnimalIritisC-Reactive ProteinDouble-Blind MethodDisability EvaluationAutoimmune DiseasesCollagen Type IICase-Control StudiesJoint DiseasesRats, Inbred LewMice, Inbred C57BLAnti-Inflammatory Agents, Non-SteroidalCohort StudiesImmunosuppressive AgentsSkinImmunologic FactorsTime FactorsBiological ProductsDrug Therapy, CombinationAge of OnsetEnzyme-Linked Immunosorbent AssayProspective StudiesQuality of LifeInterleukin-6PrevalenceEtretinateT-LymphocytesRisk FactorsMice, KnockoutHLA-B39 Antigen