Anterocollis and anterocaput

Abstract

Anterocollis/anterocaput is a subtype of cervical dystonia and the most infrequent of its abnormal head-positions. Anterocollis can be differentiated from anterocaput by the abnormal angle between thoracic and cervical spine or between skull-base and vertebrum-1 in anterocaput. Anterocollis/anterocaput is classified as primary (idiopathic) or secondary (due to identifiable neurological disease) and as pure or complex. Complex anterocollis is most frequently associated with other types of focal dystonia, such as torticollis or laterocollis. Patients complain about impaired head-movement and report to release the fixed head-position occasionally by a "geste antagonistique". Neurological exam shows tonic (contractures with anteflexion) or tremulous head-movements and neck-posturing. The diagnosis is based on the clinical presentation, needle-electromyography to identify affected muscles and rule out other conditions, X-ray of the cervical/thoracic spine, and cerebral MRI. Treatment of choice is botulinum toxin. If botulinum toxin is ineffective, drug-treatment can be tried. If botulinum toxin and drug treatment fail, deep brain-stimulation of the internal pallidal globes should be considered.

Keywords: Anterocollis; Botulinum toxin; Cervical dystonia; Dropped head; Focal dystonia.