Many people are under the impression that MRIs are better than X-Rays. This is simply not so. They both have a specific purpose. Here's why.
The main differences between an X-Ray and an MRI are the images they produce. An X-Ray clearly shows the contrast between soft tissue and bone density.
That is why it is often used to examine broken bones. An MRI image shows a better contrast between different kinds of soft issue. That is why it produces such detailed images of other tissues.
A doctor may order X-Rays first to rule out broken bones and prescribe physical therapy for a few weeks. If the condition does not improve after a few weeks, he then may order an MRI to see what the problem is. This way, resources are not wasted unnecessarily and the cost of your care is kept down.
The bottom line is that MRIs are not always necessary right away.