Adult onset idiopathic isolated focal dystonia (AOIFD) is the third most common movement disorder. Its inheritance is autosomal dominant with a penetrance of 12-15%; sporadic cases are common due to markedly reduced penetrance. Cervical dystonia is the most frequent phenotype of AOIFD, however its pathogenesis remains unknown.
Cervical dystonia (CD) or spasmodic torticollis is characterised by ofen painful involuntary neck muscle contractions, causing your head to twist or turn to one side or tilt forward or backwards. It's a rare disorder which most often occurs in middle-age and affects more women than men.