Abstract
Background: Botulinum neurotoxin A (BoNT) is the first line treatment for cervical dystonia (CD) and treatment outcome significantly depends on the correct identification of the muscles involved.
Phenomenology shown: In a case with insufficient response to BoNT treatment further work up with magnetic resonance imaging (MRI) of the neck revealed a hypertrophic spinalis cervicis muscle, that is not commonly involved in CD.
Educational value: This highlights the use of MRI for muscle selection in treatment refractory CD cases.