Arthritis, PsoriaticArthritis, RheumatoidArthritisPsoriasisArthritis, ExperimentalArthritis, InfectiousPrevalenceArthritis, JuvenileArthritis, ReactiveJointsAntirheumatic AgentsSynovial MembraneSpondylitis, AnkylosingSynovial FluidSeverity of Illness IndexSynovitisNail DiseasesRheumatic DiseasesHand JointsRheumatoid FactorSpondylarthropathiesOsteoarthritisSpondylitisToe JointReceptors, Tumor Necrosis FactorMethotrexateTumor Necrosis Factor-alphaArthrographyFinger JointBlood SedimentationFoot JointsImmunoglobulin GSpondylarthritisAntibodies, MonoclonalTreatment OutcomeDermatologic AgentsPeriostitisArthritis, GoutyHLA-C AntigensRheumatologyAntibodies, Monoclonal, HumanizedRisk FactorsSacroiliac JointCross-Sectional StudiesMice, Inbred DBAHLA-B27 AntigenGenetic Predisposition to DiseaseAutoantibodiesCohort StudiesKnee JointInjections, Intra-ArticularIritisDisability EvaluationQuestionnairesCase-Control StudiesAnti-Inflammatory AgentsBiological MarkersDouble-Blind MethodJoint DiseasesCollagen Type IIProspective StudiesAge of OnsetAutoimmune DiseasesQuality of LifeBiological ProductsImmunosuppressive AgentsDrug Therapy, CombinationGenotypeFollow-Up StudiesTime FactorsGene FrequencyRats, Inbred LewImmunologic FactorsNewfoundland and LabradorHealth StatusEtretinateUnited StatesHLA-B39 Antigen