<prompt> Radiological sign in case of Pehes disease ?Epiphyseal calcificationOrganized calcificationLateral subluxation femur headRestriction of abduction  <response>: Ans. is b i.e., PA factor positive Seronegative spondvloahropathies The seronegative spondyloahropathies are a group of disorders that share ceain clinical features and genetic associations. The word seronegative referes to the absence of rheumatoid factor in this group of disorders. The seronegative spondyloahropathies include ? Ankylosing spondylitis Reactive ahritis -- Reiter syndrome and enteritis associated ahritis Psoriatic ahritis Ahritis associated with inflammatory bowel disease, i.e. enteropathic ahritis Features of seronegative spondyloahropathies o Onset usually before 40 years Absence of RA factor HLA - B27 positive Presence of uveitis 