Question
Hey there. Is it possible to have functional scoliosis show up on an xray but not a MRI?

Answer
Dear Terry,

Good question, short and to the point...

The answer lies in the reasons why the two different tests are ordered in the first place.  X-rays are good for looking at structure in general, including curves and postural positions. They help us to see the gross anatomy of the bone structures. The best x-rays for determining a scoliosis are done when the patient is weight bearing, meaning that they are standing.  Some curves can change when the patient goes from standing to sitting, or from standing to lying down.

An MRI is not performed to rule in or rule out the condition of scoliosis, so a typical MRI report usually doesn't even mention whether or not the patient has a scoliosis. An MRI looks at each individual spinal segment and joint through slice pictures. An MRI helps to see disc problems and to look for spinal tumors. It is not given as a study to analyze the postural position or curves of the spine.  

So... Yes, you can have an x-ray report that gives a diagnosis of a scoliosis on simple spinal x-ray, and have an MRI of the same spine, with radiological written report, that makes no mention of scoliosis. Radiologists do not look for scoliosis in an MRI. It is not the ideal study for that purpose.

Terry, I hope that this helps you to better understand the two different tests and their usage relative to scoliosis. Here is a link that describes the difference between a functional and structural scoliosis. Basically, a functional scoliosis is described as a curve that can change with positions, such as standing or lying down, while a structural scoliosis will not change with positions.  http://www.theamericanchiropractor.com/articledetail.asp?articleid=912&category=...

Keith Biggs, DC
http://www.eastmesachiropractor.com