My son 20 year old His latest MRI report is: Focal areas of sclerosis are seen along the artcular surface of both Focal areas of sclerosis. There is reduced joint space with erosion s of articular margins along both sacro iliac joints there is mild enhancement of ligamentous and synovial parts of sacoiliac joints bilaterally representing enthesitis and synovitis respectively Patch abnormal high signal intensity areas on STIR images showing post constrast enhancements are also seen involving the sacrum and iliac bone in sub articular locations representing osteitis. One Doctor prescribed Inj Enbrel The other says that we may try first Inj Endonax Kindly tell me which one is better and side effects.