Torticollis or wryneck is a condition characterized by lateral twisting of the neck, causing the head to tilt to one side and the chin rotating to the opposite side. A myriad of conditions can cause torticollis, but it must be emphasized that the differential diagnosis is quite different for infants (or babies) in comparison with children and adolescents.
Newborn baby having torticollis neck waiting for massage - Image Copyright: Blaj Gabriel / Shutterstock
The most common cause of torticollis in babies is congenital muscular torticollis linked to a contracture of the sternocleidomastoid muscle. Some unusual non-muscular causes of torticollis in babies also have to be considered, including benign paroxysmal torticollis, ocular torticollis caused by the disturbances in the oculomotor nerves, Sandifer’s syndrome as a result of gastroesophageal reflux disease, as well as neural axis abnormalities.
Congenital Muscular Torticollis
Congenital muscular torticollis is also known as wry neck, crooked neck and caput obstipum and represents a condition caused by unilateral fibrosis of the sternocleidomastoid muscle – the big ropey muscle that allows our neck to turn and rotate. Although numerous explanations and pathophysiological mechanisms have been proposed, the true etiology of this condition remains uncertain.
Still, various causes implicated in the development of congenital muscular torticollis include fibrosis form bleeding during birth, traumatic child delivery, intrauterine crowding, primary myopathies of the sternocleidomastoid muscle, as well as an intrauterine compartment syndrome of the same muscle.
The condition is already present at the time of birth (or develops right after birth), but it is generally discovered during the first 6 - 8 weeks after birth, when a newborn starts to gain control over the movement of head and neck. Furthermore, some infants with congenital muscular torticollis also present with developmental dysplasia of the hip – a dislocation of the hip joint present from birth and more frequently observed in girls.
In addition to head tilting, in babies with this condition the range of motion around the neck is limited, and they usually present with a soft lump in the neck muscle, and flattening of a side of the face due to sleeping on that side. In up to 90% of babies with congenital muscular torticollis, a plagiocephaly (flattening of one side of the baby’s skull) can be observed.
Observation and adequate physical therapy (with or without bracing) is usually sufficient in most cases of congenital muscular torticollis, especially if it is introduced within the first year of baby’s life. Stretching exercises including turning the neck from one side to another and slowly tilting the baby’s head to position the ear on the normal side are perfomed many times a day.
Botulinum toxin-A (popularly known as Botox) has recently been demonstrated as an effective intermediate treatment approach for more recalcitrant cases of congenital muscular torticollis. The sternocleidomastoid muscle lengthening often improves the range of motion, but not necessarily the facial asymmetry, plagiocephaly or cranial molding.
Other Causes of Torticollis in Infants
Benign paroxysmal torticollis represents a rare functional disorder in infants and is characterized by recurrent episodes of torticollis in healthy children. It usually occurs within the first three months of life with the unknown prevalence, but the benign nature of the disorder means that no treatment is necessary and the prognosis is excellent (although more serious conditions have to be excluded in the differential diagnosis).
Even though it can be seen in babies after four months of age, ocular torticollis usually manifests later than congenital muscular torticollis, according to the binocular-vision-development period. Common causes of ocular torticollis are congenital nystagmus and congenital paralytic squint.
Sandifer’s syndrome represents a rare pediatric condition that involves dystonic and abnormal movements of the neck, head, trunk, and upper extremities, and that is associated with gastro-esophageal reflux disease. Although the precise pathophysiology is unknown, dystonic movements and the posture of the head and neck are thought to arise as a response to the pain associated with gastro-esophageal reflux.
Neural axis abnormalities include, for example, Arnold-Chiardi syndrome and syringomyelia. Torticollis can be an early finding in both of these conditions, but also a presenting sign of cervical spine infection (osteomyelitis) and/or a tumor (such as pilocytic astrocytoma and extradural neuroblastoma).