What is the best machine (x-ray, ct scan or mri) to see/identify arthritis? more specifically for hip and back arthritis. thank you :)

X-ray often good: Each imaging modality has its own strengths and weaknesses. Usually will start with a regular x-ray..Since it may answer the question, is fast, easy and less expensive. If it does not answer the question, a ct or MRI may be needed. The MRI would be the best to see if there is nerve root impingement, and is best for looking at the discs.

Well it depends: Ct and xray shows bone but not muscle, cartilage, labrum, bursitis or disc herniation as well as mri. So after a normal xray - or just an xray showing spurs most doctors order a 3t MRI if they really want to see the labrum (can diagnose labral tears without contrast). And as a neuroradiologist i would say that 3t (if possible) MRI is much better in imaging the back - do a web search.