Arthritis, PsoriaticPsoriasisArthritis, RheumatoidArthritisArthritis, ExperimentalArthritis, InfectiousArthritis, JuvenileArthritis, ReactiveJointsAntirheumatic AgentsDermatologic AgentsSynovial MembraneSpondylitis, AnkylosingSynovial FluidNail DiseasesSeverity of Illness IndexSynovitisRheumatic DiseasesHand JointsRheumatoid FactorReceptors, Tumor Necrosis FactorHLA-C AntigensSpondylitisTumor Necrosis Factor-alphaMethotrexateSpondylarthropathiesOsteoarthritisToe JointAntibodies, MonoclonalArthrographyBlood SedimentationImmunoglobulin GFinger JointSpondylarthritisFoot JointsTreatment OutcomePeriostitisAntibodies, Monoclonal, HumanizedArthritis, GoutyGenetic Predisposition to DiseaseRheumatologySkinPUVA TherapyUltraviolet TherapySacroiliac JointHLA-B27 AntigenMice, Inbred DBAAnti-Inflammatory AgentsIritisAutoantibodiesCase-Control StudiesKnee JointInjections, Intra-ArticularDouble-Blind MethodDisability EvaluationBiological ProductsImmunosuppressive AgentsBiological MarkersAge of OnsetAutoimmune DiseasesCohort StudiesImmunologic FactorsCollagen Type IIQuality of LifeJoint DiseasesCornified Envelope Proline-Rich ProteinsEtretinateNailsGene FrequencyPrevalenceDrug Therapy, CombinationCytokinesRats, Inbred LewAnti-Inflammatory Agents, Non-SteroidalHLA AntigensRisk FactorsQuestionnairesCoal TarProspective Studies