CT-guided sacroiliac joint injection for chronic sacroiliitis: outcomes and predictors in a retrospective cohort study

PURPOSE: To evaluate the safety, technical success, and clinical outcomes of CT-guided sacroiliac joint (SIJ) injections in patients with chronic sacroiliitis and to assess the impact of disease etiology, age, and body mass index (BMI) on therapeutic response. MATERIALS AND METHODS: This retrospective study included 80 patients with clinically and radiologically confirmed sacroiliitis who underwent CT-guided intra-articular SIJ injection between February 2020 and May 2022. Pain and disability were assessed using the Numerical Rating Scale (NRS) and the Oswestry Disability Index (ODI) at baseline and at 1-week, 1-month, and 6-month follow-up intervals. Patients were stratified by etiology (inflammatory vs degenerative), age, and BMI. RESULTS: All procedures were technically successful and complication-free. Mean NRS scores improved from 6.86 ± 1.20 at baseline to 2.26 ± 0.78 at 6 months (p < 0.001). ODI scores decreased from 37.28 ± 9.84 to 5.68 ± 2.49 (p < 0.001). Greater ODI improvement was observed in inflammatory cases compared to degenerative ones (p < 0.05), though both subgroups showed significant clinical benefit. Age and BMI did not significantly affect outcomes. CONCLUSION: CT-guided SIJ injection is a safe and effective intervention for sacroiliitis, yielding sustained pain relief and functional improvement across both inflammatory and degenerative etiologies, independent of age and BMI.