A 21-day-old boy is brought to the office by his mother because of a palpable bulge in the child's neck. He continues to feed well but appears comfortable only when held with his body sideways under the breast. He is at the 50th percentile for height, weight, and head circumference. The child favors looking toward the right and cries when his head is turned to the left. There is a firm mass on the left side of his neck that does not move when the child swallows. The remainder of the examination is unremarkable. Which of the following conditions was most likely present prenatally?

Question

A 21-day-old boy is brought to the office by his mother because of a palpable bulge in the child's neck.  He continues to feed well but appears comfortable only when held with his body sideways under the breast.  He is at the 50th percentile for height, weight, and head circumference.  The child favors looking toward the right and cries when his head is turned to the left.  There is a firm mass on the left side of his neck that does not move when the child swallows.  The remainder of the examination is unremarkable.  Which of the following conditions was most likely present prenatally?

Quizplus · Accepted Answer

11ec160b_3a01_f1f4_9249_4542a9550077_MD0001_00 This infant has congenital torticollis, which typically develops by 2 to 4 weeks of age. It is most commonly caused by birth trauma (eg, breech delivery) or malposition of the head in utero (eg, due to fetal macrosomia or oligohydramnios), both of which can result in sternocleidomastoid muscle (SCM) injury and fibrosis. Children with congenital torticollis may have additional musculoskeletal anomalies, including hip dysplasia, metatarsus adductus (ie, adduction of the forefoot), and talipes equinovarus (ie, clubfoot). The diagnosis of congenital torticollis is made clinically. On physical examination, the head is tilted toward the affected side with the chin pointed away from the contracture. A soft-tissue mass may be palpable in the inferior one-third of the affected SCM. Plagiocephaly and facial asymmetry may be seen in severe cases. Most cases resolve with conservative therapy and stretching exercises. (Choice A) Folate deficiency during the first trimester of pregnancy is associated with fetal neural tube defects (eg, spina bifida). (Choice C) Defective collagen synthesis causes osteogenesis imperfecta (brittle bone disease). Patients with the lethal variety usually die in utero or in early infancy due to severe fractures, pulmonary failure, or intracerebral hemorrhage. (Choice D) Alcohol consumption during pregnancy can cause fetal alcohol syndrome. Affected infants have poor growth, functional developmental deficits, and characteristic facial abnormalities including a smooth philtrum, thin vermilion border, and small palpebral fissures. (Choice E) The majority of upper respiratory infections in pregnancy are benign. However, rubella, one of the TORCH infections, is transmitted by the respiratory route and can cause severe birth defects, including hearing loss, cataracts, and congenital heart defects. Educational objective: Congenital torticollis is typically noted by 2 to 4 weeks of age, after which the child prefers to hold the head tilted to one side. It is most commonly the result of malposition of the head in utero or birth trauma. Most cases resolve with conservative therapy and stretching exercises. __________ References: Torticollis in infants and children: common and unusual causes. (http://www.ncbi.nlm.nih.gov/pubmed/16958498)

A 21-Day-Old Boy Is Brought to the Office by His