Congenital muscular torticollis (CMT) or torticollis as it is often referred to, literally means a condition that is present at birth that causes the neck to twist. It is caused by a shortened muscle on one side of an infant's neck which produces a tilting of the neck to the affected side and a rotation of the head to the opposite side. The incidence is about 1 in 250 births. There are other causes of torticollis such as vertebral abnormalities which is different from CMT in that it is quite rigid, and resists any attempt at correcting it passively.
