Fluoroscopy Versus Ultrasound Guidance for Sacral Lateral Branch Radiofrequency Ablation

Inclusion Criteria: * Low back pain due to sacroiliac joint dysfunction \>6 months with a score ≥ 4 on a numeric rating scale. * 50% pain relief after prognostic sacral lateral branch block * At least 3 positive physical examination maneuvers \[ Faber ( flexioni abduction and external rotation), POSH (posteripr shear), REAB ( resisted abduction), Gaenslen's test, Distraction test\] * Refractory to conservative therapy Exclusion Criteria: The exclusion criteria were; * Uncontrolled psychiatric or neurological illness * Sacroiliac joint pain due to other disorders, * Lumbar radiculopathy * Rheumatological diseases * Systemic active infections * Malignancies, previous surgery on the affected sacroiliac joint, * History of traumatic hip injury, * History of bleeding disorders, * Platelet values \< 150.000 / µl, * Sacroiliac joint injection within the preceding 3 months, * Allergy to local anesthetics and steroids, * Pregnancy, inability to concent, Implanted pacemaker or defibrilator.