Aims: Previous data suggests that patients with juvenile-onset ankylosing spondylitis (JoAS) have more severe disease and worse functional outcomes than adult-onset AS (AoAS). The purpose of this study was to evaluate clinical, functional and radiographic differences between patients with JoAS and AoAS in a large cohort of patients with long-standing disease. METHODS: A total of 402 subjects who met the Modified New York Criteria for definitive AS and had had disease >or=20 years were enrolled in a multi-centre cross-sectional study (Prospective Study of Outcomes in Ankylosing Spondylitis; PSOAS). JoAS was defined as initial symptoms 展开▼
