I am not sure of the answer. I don't think an MRI is 100% in showing problems of the spine. I think it is a fairly good test though which may show existing problems but not 100%. I think the MRI may show if there is compression on the nerves but other tests should be done to show if ther is nerve problems such as an EMG.
Was your MRI done with or without contrast? I have always heard an MRI is better then a CT scan.