O-arm-guided sacroiliac joint injection: New techniques with reflux test.

Diagnosis of degenerative sacroiliac pain syndrome is difficult. Sacroiliac injection confirms diagnosis by relieving pain. The present study aimed to describe a sacroiliac injection technique under O-arm guidance. Fifty-four patients, with a mean age of 58 years, presenting resistant sacroiliac pain syndrome after two 2D CT-guided injections received O-arm guided sacroiliac injection. Anesthetic reflux on joint lavage validated the technique. Clinical efficacy was assessed as pain relief on a simple numeric scale (positive if>70%). Reflux was observed in 92% of cases. Pain was relieved in 81%, with mean score reduced to 3.1 from 8.5. O-arm guided sacroiliac injection was reproducible and relieved sacroiliac pain after failure of 2D-guided injection, thus confirming the clinical diagnosis.