SUMMARY Congenital muscular torticollis is caused by abnormal contraction of the sternocleidomastoid (SCM) The condition typically presents in infants and children with a persistent head tilt toward the involved side Diagnosis is clinical, based on the presence of a palpable neck mass from a contracted SCM with the chin rotated toward the contralateral side Treatment is typically passive stretching, and the condition usually resolves within a year. Surgical lengthening of the SCM is indicated after failure of at least 1 year of stretching Epidemiology Incidence most common cause of infantile torticollis 0.3-2.0% Demographics 3:2 male-to-female ratio Anatomic location neck Risk factors oligohydramnios first pregnancy (limited intrauterine space) traumatic delivery breech delivery Etiology Pathophysiology contracture of the SCM cervical rotational deformity with the chin rotated away from the affected side and head tilted toward the affected side suspected muscle injury from compression and stretching of the SCM venous outflow obstruction compression that leads to decreased blood supply and subsequent compartment syndrome Associated conditions associated with other packaging disorders developmental dysplasia of the hip (5-15% association) metatarsus adductus calcaneovalgus feet plagiocephaly (asymmetric flattening of the skull) occurs on the contralateral side congenital atlanto-occipital abnormalities ANATOMY Sternocleidomastoid (SCM) muscle origins sternal head: anterior surface of manubrium sterni clavicular head: superior surface of medial third of the clavicle insertions lateral surface of the mastoid process on the temporal bone lateral occipital bone innervation cranial nerve XI (spinal accessory nerve) at risk during SCM release function ipsilateral neck flexion, contralateral head rotation PRESENTATION Symptoms head tilt and rotation painless passive motion Physical exam inspection palpable neck mass from the contracted SCM usually noted during the newborn exam or within the first 4 weeks of life head tilt and rotation head tilt toward the affected SCM chin rotation away from the affected SCM conduct routine newborn exam assess vision, hearing, and neurologic function examine for hip dysplasia, foot deformities, and spine abnormalities motion restriction of rotation and lateral flexion of the neck in older children SCM mass becomes a tight band IMAGING Radiographs recommended views AP and lateral views of the cervical spine indications head tilt and rotation with no palpable mass present rule out other bony conditions that can cause torticollis CT recommended views dynamic CT scan scan at C1-2 with the head in neutral, then in maximum rotation to the left and right indications rule out atlantoaxial rotatory subluxation MRI recommended views MRI brain and cervical spine indications rule out non-muscular and central nervous system causes of torticollis Ultrasound indications head tilt and rotation with decreased ROM in the presence of a palpable mass differentiate congenital muscular torticollis from more serious underlying neurologic or osseous abnormalities findings larger and hyperechoic SCM (due to fibrosis) on the involved side when compared to the contralateral side DIFFERENTIAL Atlantoaxial rotatory subluxation painful (unlike congenital muscular torticollis, which is painless) post-traumatic or post-infectious (Grisel's disease) Klippel-Feil syndrome classic triad: short, webbed neck low posterior hairline limited cervical ROM Ophthalmologic and vestibular conditions Lesions of the central and peripheral nervous systems TREATMENT Nonoperative passive stretching indications condition present for <1 year <30° limitation in ROM outcomes 90-95% respond to passive stretching in the first year of life Operative bipolar release or Z-lengthening of the SCM indications failure of at least 1 year of stretching outcomes good outcomes (92% success), even in older children facial asymmetry can improve as long as release is performed prior to 10 y/o TECHNIQUES Passive stretching technique stretch in the direction opposite of the deformity lateral head tilt away from affected side chin rotation toward the affected side Bipolar release of SCM or Z-lengthening technique proximal short incision behind the ear to divide the SCM distal single or dual incisions to reach the sternal and clavicular attachments of SCM complications SCM branch of CN XI (spinal accessory nerve) is at risk COMPLICATIONS Permanent rotational deformity risk factors untreated or undiagnosed Positional plagiocephaly risk factors untreated or undiagnosed Craniofacial deformities facial asymmetry facial hemihypoplasia Compensatory scoliosis Prognosis Typically resolves with stretching within the first year of life If left untreated permanent rotational deformity positional plagiocephaly craniofacial deformities facial asymmetry facial hemihypoplasia compensatory scoliosis