Francis William Smith MD, Presenter: Nothing to Disclose

To improve diagnosis in patients following whip-lash injury

20 patients (14 female, 6 male) age range 15 - 69 yrs (Mean 47yrs), previously investigated following a hyperextension injury of the neck with reportedly normal MRI examination of the cervical spine were entered in to the study. Previous MRI examinations had comprised sagittal T1 & T2 weighted images together with axial T2 weighted images at all levels from C2/3 to C7/T1 . For the study, patients were studied in the seated upright position, where in addition to the sequences above, had a series of Coronal T2 weighted images and coronal and axial proton density images made from the skull base down to the C2/3 level.Spinal alignment, integrity of the intervertebral discs, alignment of the atlanto axial joints and atlanto-occiptal joints, the integrity of the alar and cruciate ligaments, as well as the integrity of the neck muscles were assessed in all cases. If dislocation of either the atlanto-axial or atlanto-occipital joints were observed, further axial imaging at these levels was made with the head turned to the right and the left to assess for instability.

In 50% of the patients, the comprenhensive imaging protocol found no cause that could be attributed to hyperextension injury of the neck. In the other 10 patients, eight had dislocation at the atlanto-axial joint two of which showed instability when the rotation images were assessed. Two showed stable dislocation at the antlanto-occipital joint, one of which also had low lying cerebellar tonsils.

We believe that the accepted practice of imaging the cervical spine, limiting the axial images to below the axis is inadequte and under estimates the incidence of significant post traumatic dislocation above this level. For thorough MRI examination of the neck in patients following hyper-extension injury, the use of good resolution imaging of the cranio-cervical junction in both the coronal and axial planes is mandatory, both to find evidence of dislocation and also to exclude it when it is not present.

The cost implications of under diagnosis of mechanical damage at the cranio-cervical junction, both in terms of patient suffering and cost in insurance claims, is very large. We believe it is of paramount importance to not only to show dislocation and ligamentous damage when present, but also to categorecally exclude such damage when it is not present.

Smith, F, Diagnostic Accuracy of MRI Following Whiplash Injury Is Improved by Routine Imaging of the Cranio-cervical Junction.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14008738.html