Summary of function, disease activity, and metrology in juvenile-onset (JoAS) versus adult-onset ankylosing spondylitis (AoAS).
| Domain | Characteristic | JoAS More Likely/Higher/Worse (Ref. No.) | Equal JoAS & AoAS (Ref. No.) | AoAS More Likely/Higher/Worse (Ref. No.) |
|---|---|---|---|---|
| Function | ||||
| BASFI | (5, 6, 11) | (12, 14, 16) | (7) | |
| BASFI domains | (6) | |||
| Functional capacity (Steinbrocker) | (10) | |||
| Functional class (ACR criteria) | (8) | |||
| ASAQ (including spinal mobility) | (9) | |||
| Disease activity | ||||
| BASDAI | (5) NS (16) | (11, 12) | ||
| Metrology | ||||
| BASMI | (5, 11, 16) | (12) | ||
| Wall to tragus distance | (8) | |||
| Cervical spine rotation | (12) | |||
| Lumbar forward flexion (Schober) | (8) | |||
| Spinal forward flexion (Bruckel deformity score) | NS (6) | |||
| Lumbar lateral flexion | (12) | |||
| Chest expansion | (8, 12) | |||
| Forced vital capacity | (8) | |||
NS: not statistically significant; ACR: American College of Rheumatology; BASDAI: Bath AS Disease Activity Index; BASFI: Bath AS Function Index; BASG: Bath AS Patient Global; BASMI: Bath AS Metrology Index; ASAQ: Ankylosing Spondylitis Assessment Questionnaire.