Computed tomography guided corticosteroid injection of the sacroiliac joint in patients with spondyloarthropathy with sacroiliitis: clinical outcome and followup by dynamic magnetic resonance imaging

Abstract

Objective: To evaluate computed tomography (CT) guided corticosteroid injections of inflamed sacroiliac (SI) joints in patients with spondyloarthropathies (SpA), and to evaluate dynamic magnetic resonance imaging (DMRI) of the SI joints in serial examinations of these patients, who had different degrees of inflammatory back pain.

Methods: We examined and treated 30 patients with ankylosing spondylitis (n = 9) or undifferentiated SpA (n = 11) (14 women and 16 men, mean age 36.5 +/- 13.4 years, mean disease duration 5.4 +/- 4.0 years) who had severe inflammatory back pain for more than 3 months. All patients had DMRI of the SI joints before and 4-6 months after a CT guided injection of 40 mg triamcinolone acetonide into SI joints (n = 54; 24 patients received injections in both joints). Enhancement of the contrast agent gadolinium-DTPA was quantified by calculating the enhancement of the contrast agent gadolinium-DTPA was quantified by calculating the enhancement gradient Fenh. A subjective index with a visual analog scale (0 = no pain, 10 = very severe pain) was used for assessment of back pain. Followup visits were done every 3 months for a maximum of 18 months.

Results: There was significant improvement of inflammatory back pain and sacroiliitis at 5.2 +/- 1.3 months after therapy in 25/30 patients (83.3%). The differences between the Fenh values before (98.2 +/ 56.1) and after (44.3 +/- 31.2) therapy and of the subjective pain index (8.5 +/- 1.5 and 3.0 +/- 2.3, respectively) were statistically significant. Subjective improvement lasted a mean of 8.9 +/- 5.3 months.

Conclusion: CT guided corticosteroid injection of inflamed SI joints is a useful option in therapy for sacroiliitis in patients with SpA. Different degrees of inflammation in the SI joints can be quantitatively assessed by DMRI.