I believe x-rays would be the best to see the bone structures to look for bone issues such as osteophytes, fractures, breaks, etc. An MRI would be much better to see soft tissue problems, such as disc herniations, cysts & other masses, ligament problems, etc. Other than that, just what Tet said...they usually do some neurologic exams, test your reflexes, perhaps have you try to bend in different directions; Then they would look at your x-rays and/or MRI's and try to put it all together.