Pars defects can be difficult to see on MRI. Lets look at how best to find them.
WHAT IS THE PARS INTERARTICULARIS?
Bone that connects the superior and inferior articular process at each level.
WHAT DOES A NORMAL PARS INTERTICULARIS LOOK LIKE ON MRI?
- A continuous piece of bone extending from the pedicle down to the inferior articular process
WHAT DOES A PARS DEFECT LOOK LIKE ON MRI AND WHICH PLANE IS BEST TO SEE IT?
- The best plane is Sagittal. More difficult to see on axial.
- The KEY is to see a continuous piece of bone between the superior and inferior articular processes
- If you dont see a continuous bone, there is a pars defect
- Sometimes need to follow on 2-3 slices as it may not be in a true sagittal plane
See also our post on Spondylolisthesis: From Pars Defect or Degeneration: How to differentiate quickly