Evaluation of MR imaging guided steroid injection of the sacroiliac joints for the treatment of children with refractory enthesitis-related arthritis.

Objectives: To test the hypothesis that MR imaging guided triamcinolone acetonide injection into the sacroiliac joints of children with enthesitis-related arthritis is feasible, accurate and safe; and effectively reduces sacroiliac inflammation and disease progression.
Methods: A retrospective analysis of 14 children (6/14 [43%] female, 8/14 (57%) male; mean age, 13.2 years; range, 6-16 years) who received MR imaging guided sacroiliac joint injections at 0.2 Tesla or 1.5 Tesla for enthesitis-related arthritis and acute sacroilitis refractory to medical therapy was performed. 20 mg triamcinolone acetonide were injected. Assessed were intra-articular drug delivery; image quality, duration, and complications. Success of therapy was defined by change of sacroiliac inflammation. Remission time and erosions were assessed by follow-up MRI (range, 10-22 months).
Results: Twenty four procedures resulted in intra-articular injection. Image quality was sufficient. No complications occurred. Procedure time was 40 min. Sedation time was 22 min. Success of therapy was achieved in 11/14 (79%) children. Sacroiliac inflammation decreased significantly (-59%). Median remission time was 13.7 months. No erosions occurred.
Conclusions: MR imaging guided steroid injection of the sacroiliac joints is feasible, accurate, and safe and can effectively reduce sacroiliac inflammatory activity and may therefore aid in the prevention of disease progression.