Congenital muscular torticollis (CMT) is the most common cause of abnormal posture of the head and neck in infancy. Familial transmission of CMT has not been reported in Korean literature, to our knowledge. Four cases with CMT found in siblings are presented in this paper along with the review of literature on hereditary factor as one of the possible mechanisms on pathogenesis of CMT. Further case reports are required in order to verify heredity as a possible pathogenetic factor of CMT. (J Korean Acad Rehab Med 2009; 33: 731-734)
