Early recognition of unilateral absence of sternocleidomastoid muscle in a newborn presenting with contralateral congenital torticollis

A term infant was noticed to have right-sided torticollis on day 4 ([figure 1A][1]). His neurological and spine examination were normal. He did not have a sternocleidomastoid tumour. However, the sternocleidomastoid muscle (SCM) on the opposite side could not be palpated. There was a noticeable