case_images: PMC4383127_01
case_images: Ankylosing spondylitis: sacroiliitis (roentgenogram)
case_images: AER-9-98-g001.jpg
case_images: PMC4383127_01_AER-9-98-g001.jpg
case_images: F1
case_images: Radiological studies done 1 month previously, revealed solid ankylosis of the facet joints between all lumbar vertebrae [Figure 1].
case_images: Catheters inside the psoas compartment and parasacral space
case_images: AER-9-98-g002.jpg
case_images: PMC4383127_01_AER-9-98-g002.jpg
case_images: F2
case_images: Approximately, 5 mL of contrast (iohexol with 300 mg/mL Ominipaque ) were injected in both catheters to study the dispersion of a local anesthetic [Figure 2].