SUMMARY Congenital Muscular Torticollis is a musculoskeletal deformity caused by the abnormal contraction of the sternocleidomastoid muscle. The condition typically presents in infants and children with a persistent head tilt toward the involved side. Diagnosis is made clinically with the presence of a palpable neck mass from a contracted sternocleidomastoid muscle with the chin rotated towards the contralateral side. Treatment is typically passive stretching with the condition resolving within a year. Surgical lengthening of the SCM muscle is indicated with failed response to 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 sternocleidomastoid (SCM) cervical rotational deformity with chin rotation away from the affected side and head tilt towards the affected side suspected muscle injury from compression and stretching of SCM venous outflow obstruction compression leading 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 contralateral side congenital atlanto-occipital abnormalities ANATOMY Muscles sternocleidomastoid muscle (SCM) origins sternal head - anterior surface of manubrium sterni clavicular head - superior surface of medial third of clavicle insertions lateral mastoid process on temporal bone lateral occipital bone innervation cranial nerve XI - spinal accessory nerve at risk when operatively releasing SCM function ipsilateral neck flexion, contralateral head rotation PRESENTATION Symptoms head tilt and rotation painless passive motion Physical exam inspection palpable neck mass from contracted SCM usually noted within the first four weeks of life or during newborn exam head tilt & rotation neck tilt towards the affected SCM chin rotation away from the affected SCM conduct routine baby exam assess visual function, auditory assessment, and neurologic exam examine for hip dysplasia, foot deformities, as well as spine abnormalities motion in older children - restriction of rotation and lateral flexion of neck mass becomes a tight band IMAGING Radiographs recommended views AP and lateral 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-C2 level with head straight, then in maximum rotation to left and right indications rule out atlantoaxial rotatory subluxation MRI recommended views MRI brain and cervical spine indications rule out non-muscular and central causes of torticollis Ultrasound indications head tilt and rotation with decreased ROM in the presence of a palpable mass findings larger and hyperechoic (due to fibrosis) SCM on involved side when compared to contralateral side differentiate congenital muscular torticollis from more serious underlying neurologic or osseous abnormalities DIFFERENTIAL Atlantoaxial rotatory subluxation painful (compared to painless for congenital muscular torticollis) post-traumatic or post-infectious (Grisel's disease) Klippel-Feil syndrome classic triad: short webbed neck low posterior hairline limited cervical range of motion Ophthalmologic and vestibular conditions Lesions of central and peripheral nervous system TREATMENT Nonoperative passive stretching indications condition present for less than 1 year less than 30° limitation in ROM outcomes 90-95% respond to passive stretching in the first year of life Operative bipolar release of SCM or Z-lengthening indications failed response to at least 1 year of stretching outcomes good outcomes (92% success), even in older children facial asymmetry can improve as long as release done prior to 10 years of age TECHNIQUES Passive stretching technique 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 short, proximal incision behind the ear to divide SCM single or dual incision to reach sternal and clavicular attachments of SCM complications SCM branch of CN XI (spinal accessory nerve) is at risk COMPLICATIONS Permanent rotational deformity risk factors left untreated or unnoticed Positional plagiocephaly risk factors left untreated or unnoticed Craniofacial deformities facial asymmetry facial hemihypoplasia Compensatory scoliosis Prognosis Typically resolves with stretching within the first year If left untreated permanent rotational deformity positional plagiocephaly craniofacial deformities facial asymmetry facial hemihypoplasia compensatory scoliosis