Systematic assessment of inflammation by magnetic resonance imaging in the posterior elements of the spine in ankylosing spondylitis.

Objective: Magnetic resonance imaging (MRI) is sensitive for scoring inflammatory lesions in the spine, but attention has primarily focused on vertebral bodies, and no study has systematically examined the posterior elements. We aimed to systematically determine the frequency and distribution of inflammatory changes in the posterior elements of the spine using MRI, and to assess the reliability of their detection and their impact on discrimination of spinal MRI.

Methods: We scanned 32 patients recruited to placebo-controlled trials of anti-tumor necrosis factor therapy.