Why do I need to have a MRI of the lumbar spine, a CT scan of the pelvis and a nerve study prior to surgery?
Please remember that sacroiliac dysfunction is a diagnostic of exclusion. We therefore need to exclude other diseases that may mimic this problem. The MRI of the lumbar spine mainly checks for a disc herniation pinching a nerve root. The CT scan of the pelvis check for other (much rarer) diseases of the sacroiliac joint, such as infection or tumor. If your symptoms have remained the same and if you have had those tests within the last year, those would do, but we would like to see the pictures ourselves besides the report. The nerve study will check for nerves or nerve roots problems. A variation of the test (that is usually not performed in the standard test) will tell us if your sciatic nerve is pinched as it exits the pelvis.
