Fig. 20

Lumbar PsA. (a) AP and (b) lateral radiograph in a 50-year-old man show voluminous paravertebral ossifications anteriorly and at the right side of the third lumbar vertebra and adjacent iv spaces. MRI, (c) sagittal STIR, (d) T1 and (e) post-contrast T1-weighted images, demonstrates manifest osseous inflammation (osteitis) in the form of oedema and enhancement of the vertebral body, slight enhancement in the paravertebral new bone formation and erosion of the upper vertebral plate compatible with a mixture of osteitis, enthesitis and erosive changes