Bening paraxysmal torticollis is a sensoriomotos trigeminocervical convergence merchanisms? Experimental evidence.

Introduction Benign paroxysmal torticollis (BPT) is likely an age-sensitive, childhood periodic syndromes that are commonly precursors of migraine, with atypical postural behavior (torticollis) to start early and self-limited, which of unknown etiology. Objective To prove the existence of forms of sensorimotor convergence between the trigeminal nerve and upper cervical roots respectively. Methods Ninety-five rats Norvegicus were submitted to infraorbital nerve blockade using botulinum neurotoxin type A (BoNT/A) (n=48) controlled by isotonic saline solution animals (ISS) (n=47). After 84 days the animals were evaluated on their motor functions using open field test and postural behavior. Results Of the 48 animals in the BoNT/A group one animal showed the torticollis ipsilateral to BoNT/A injection. The macroscopic analysis showed fasciculations on clavotrapezius muscle. The biopsy with optical and electronic microscopy of this muscle showed changes suggestive of denervation secondary to BoNT/A. Conclusion We suggested the existence of a pathway sensoriomotor probably in the brainstem involves the trigeminal system and cervical motoneurons.