Introduction: Sacroiliac joint (SIJ) pathology is a common cause of low back pain 
(LBP), accounting for 10–27% of cases of mechanical LBP below L5 level. If there is no 
definite clinical or radiological diagnostic criteria for SIJ pain, intra-articular injection 
of SIJ have become the choice assessment method for making the diagnosis of SIJ pain.
Aim of the work: This randomized clinical trial was designed to investigate and compare 
both accuracy and efficacy of the ultrasound and fluoroscopy guidance for sacroiliac joint 
injections with local anesthetic and steroids as a treatment modality for pain relief in 
patients with moderate to severe sacroiliitis. Patients and Methods: After Minia University 
ethical committee approval (14/10/2019) and written informed consents obtained from all 
patients, this prospective randomized clinical trial was carried out on 40 adult patients of both 
sex in the period from October 2019 to March 2020 at the pain management unit of Assuit 
University Hospital. The study had been registered at the clinical trial registry. 
ClinicalTrials.gov (ID: 14102019). Results: This prospective randomized clinical trial 
included 40 adult patients of both sex, who had moderate to severe sacroiliitis and were 
candidates for sacroiliac joint injection with local anesthetic and steroids. They were 
randomly allocated into two equal groups (20 patients each) by using a computer 
generated table. The US group was treated by sacroiliac joint injection using the ultrasound. 
while the FL group was treated by sacroiliac joint injection using the fluoroscopy.