Inclusion Criteria:  Pateint >18 years old. Patients fulfilling ASAS criteria for SpA with a diagnosis confirmed by a rheumatologist. Patients having BME of the SIJ on MRI . Able to be followed-up regularly  Exclusion Criteria:  Patient < 18 years old. Malignancy, DM, Hepatitis and active infectious disorders Spine surgery. Ankylosed sacroiliac joint Recent SIJ injection