In patients with a normal cervical spine CT but persistent tenderness or neurology, how often is a subsequent MRI abnormal? And what happens afterwards? Here's an answer from Gelong...
(Spoiler alert... the real question should be, "does MRI find occult injury that results
in genuine improvements in patient-oriented outcomes? Or does it cause
harm from overdiagnosis?")
These authors from a single centre, looked retrospectively
at a cohort of trauma patients that had both a negative cervical spine CT and a
subsequent MRI. (Adult patients had to be alert and <72 hours between the
studies.)
Results?
228 patients were included.
Of the 181 patients that had the MRI for persistent
tenderness, 35 (20% or one-in-five) had an abnormal MRI. Of
those, 14 were treated with a rigid collar and no patients underwent surgery.
Of the 47 patients that had the MRI for neurological
findings, 11 (23%) had an abnormal MRI. Four patients were managed
with collars. Two patients required surgery and the manuscript described
their presentation & hospital course. Their neurologic issues were not subtle.
The authors appropriately conclude that the MRI is of “questionable”
utility in those without neurology.
But could the MRI be even worse? Could it identify injuries
that would heal just fine had we never found them only to subject patients to
weeks of unnecessary immobilisation, discomfort, and potential harm? Unfortunately, this was not really addressed in this study.
With technology advances, MRI will only get more sensitive at
finding “abnormalities." In addition, MRI will become more readily available. We
need to have some serious discussions; just because we can, should we?
Covering:
Foster G, Russel B, Hibble B, et al. Magnetic resonance
imaging cervical spine in trauma: A retrospective single-centre audit of
patient outcomes. Emerg Med Aus. 2021 Sep 3.doi: 10.1111/1742-6723.13842. [link to
article]