Congenital Muscular Torticollis
Congenital muscular torticollis is a postural deformity seen at birth or shortly after birth, primarily resulting from unilateral shortening and fibrosis of the sternocleidomastoid muscle. Infants with congenital muscular torticollis display head tilt to one side, which is often combined with rotation of the head to the opposite side. Congenital muscular torticollis is estimated to occur in one infant of every 300 live births. Plagiocephaly is reported as a coexisting impairment in 80% to 90.1% of children with congenital muscular torticollis.
Congenital muscular torticollis with impairment of the sternocleidomastoid muscle is the most frequent cause of torticollis in infants, but torticollis could also be the result of other underlying disorders. The congenital and developmental causes of torticollis in children have been classified as osseous, nonosseous, or neurogenic. The prevalence of nonmuscular causes of torticollis in children could be as high as 18%. Children with ocular torticollis could present with the postural signs of torticollis without restrictions in cervical range of movement. The child with impairment of extraocular muscles in one eye could tilt or turn the head to achieve a clear binocular view. Paresis of the superior oblique muscle could result in head tilt away from the side of impairment and is the most common source of ocular torticollis.
The pathophysiology and etiology of sternocleidomastoid impairment in congenital muscular torticollis is still unknown. Prominent theories related to the cause of sternocleidomastoid impairment in congenital muscular torticollis include intrauterine crowding, muscle trauma during a difficult delivery, soft tissue compression leading to compartment syndrome, and congenital abnormalities of soft tissue differentiation within the sternocleidomastoid muscle muscle.
Children with congenital muscular torticollis can be assigned to one of three clinical subgroups: 1) children with a palpable swelling or pseudotumor of the sternocleidomastoid, 2) children with sternocleidomastoid muscle tightness but no tumor, and 3) children with all the features of muscular torticollis without muscle tightness or tumor. An alternative system of classification considers pseudotumor of infancy and congenital muscular torticollis as separate diagnoses.
The diagnosis of torticollis is usually made by the pediatrician in the first 2 or 3 months of life when a pseudotumor of the sternocleidomastoid muscle, abnormal head posture, restricted cervical range of movement, or plagiocephaly is noted during a “well baby” visit. The mean age for diagnosis of torticollis is reported as 24 days, 9 1.1 months, 19 and 4 months.
A subgroup of children with congenital muscular torticollis develop a pseudotumor or swelling in the body of the sternocleidomastoid muscle, which can be palpated as early as 2 to 3 weeks of age. When a pseudotumor is present in the sternocleidomastoid muscle within the first few weeks of life, it is usually a soft, nontender enlargement of the muscle belly. The most frequent site of the pseudotumor is the middle to lower third of the sternal portion of the sternocleidomastoid muscle. A pseudotumor is palpated in 28.2% 1 to 47.2% 17 of infants with congenital muscular torticollis. The pseudotumor usually becomes larger after it is first noted and then slowly resolves over a period of 5 to 21 months.
Pediatricians are advised to refer infants with plagiocephaly or torticollis to physical therapy by 2 to 3 months of age if neck movement does not improve after intervention with parent instructions in the physician’s office. Children with less than 10 degrees difference in range of cervical rotation between sides could comprise a group that is easily managed with parental advisement from their pediatricians. Conservative treatment is not different for children with and without tumor.
Outcomes at 12 months of age are described as “good” for 69.3% of American children who receive conservative treatment of congenital muscular torticollis. Tight bands of residual fibrosis resulting from contracture of the sternocleidomastoid muscle muscle could be present after resolution of the pseudotumor in children for whom conservative intervention does not yield satisfactory results. Surgical intervention could be required to release the fibrotic tissues.
Surgical release of the sternocleidomastoid muscle is required more frequently when children have a history of sternocleidomastoid muscle tumor or deficits of greater than 30 degrees in cervical rotation at the time of diagnosis. Children who are younger at presentation and initiation of physical therapy are less likely to require surgery to lengthen their sternocleidomastoid muscles.
Plagiocephaly is reported in up to 90% of children with congenital muscular torticollis. Torticollis could result in deformities of the developing skull base, cranium, or face. When plagiocephaly and torticollis coexist in a neonate, they could both be the result of a limitation of the intrauterine space that caused persistent asymmetric compression of the cranium and unilateral shortening of the sternocleidomastoid muscle in the final weeks of gestation.
Congenital muscular torticollis could cause plagiocephaly in infants who do not present with plagiocephaly at birth. In cultures where young infants sleep in the supine position, unilateral compression of the skull base will occur in the child with torticollis if there is rotation of the chin away from the shortened muscle. Unilateral shortening of the sternocleidomastoid muscle causes the young infant to consistently position the head on the occiput contralateral to the tight sternocleidomastoid muscle while unloading the occiput on the ipsilateral side. With continued unilateral weight bearing, the skull base and cranium will deform so that the vertex view reveals a parallelogram-shaped head.
Mild to moderate facial asymmetries usually resolve with conservative treatment, including orthotics if necessary. The classic facial deformities associated with muscular torticollis that is severe, discovered late, or untreated have been described as “a suborbital torsional deformity of the face toward the affected side”. Deformities observed in clinical photographs included posterior displacement of the ipsilateral ear (94%), posterior regression of the ipsilateral zygoma (87%) and forehead (81%), mandibular deviation toward the affected side (44%), inferior positioning of the affected eye (31%), and deviation of the nasal tip to the affected side (19%). Skull base and cranial deformation toward a rhomboidal shape occurs before onset of facial deformities.
Deformational plagiocephaly has increased in frequency since initiation of the “back to sleep” program. Secondary contractures of the sternocleidomastoid muscle could develop in infants with deformational plagiocephaly resulting from consistent positioning with the head turned to one side. Infants with deformational plagiocephaly often present with limited extensibility of cervical muscles. However, the flattened occiput is not always opposite to the side of sternocleidomastoid muscle tightness, and examination often reveals that the sternocleidomastoid muscle is not the muscle causing the limited extensibility.
The examination of the child with torticollis should begin with a careful history to reveal the presence of coexisting conditions and to determine if the history is compatible with a diagnosis of congenital muscular torticollis. Recommendations for use of diagnostic procedures, including x-ray and imaging, vary among authors.
Treatment of the infant with torticollis is guided by the age of the infant, the severity of the torticollis, the abilities of the parents to perform the exercises and repositioning procedures, the diagnosis of plagiocephaly, and the presence of associated neuromuscular or orthopedic impairments. The first line of treatment for young infants with either deformational plagiocephaly or torticollis is aggressive repositioning. American Academy of Pediatrics guidelines instruct physicians to counsel parents in repositioning their infants in the first weeks of life.
Conservative management of infants with torticollis consists of positioning, gentle range of motion, and strengthening through activation of head and trunk muscles as the infant gains control of upright postures. Overall goals of the physical therapist in the management of infants with congenital muscular torticollis could include: 1) age-appropriate active and passive range of motion of cervical and trunk movements if possible; 2) prevention of contractures or further loss of motion in infants with sternocleidomastoid muscle nodules or significant fibrosis; 3) symmetry of shape in the face, head, and neck; 4) development of postural reactions in all directions; 5) centered upright posture of the head and neck without persistent tilt to the involved side; and 6) symmetry of gross motor patterns throughout development.
The physical therapist’s responsibilities include assessment of the infant and family to determine the causes of the child’s movement disorder followed by implementation of a management program. The home program should be incorporated into the family’s routines and include: ways to handle, feed, carry, and position the baby; activities to encourage midline head and trunk postures; and gentle active and/or passive cervical range of motion exercises opposite to the torticollis posture and away from the plagiocephalic, flattened side. Parental compliance is mandatory for successful outcomes.
Manual stretching is the most common form of treatment for congenital muscular torticollis. Proper stabilization and hand placement is vital for the success of each stretch; however, all child/parent pairs will not be comfortable with the same method of stretching or the same stretch positions. The severity of the torticollis, the age of the child, the tolerance of the child for handling, and the parent’s ability to carry out the exercise program will determine the method of stretching. When performing stretching exercises, the position of the head and neck in flexion versus extension will impact the effectiveness of the stretch. Stretches should not be painful and should be carried out by the parents and caregivers whenever possible. Reducing the intensity of the stretch slightly could avoid pain and muscle guarding. The tight muscles of infants with sternocleidomastoid muscle tumors should be gently stretched toward end range using active and passive exercises with similar intensity to the stretch imposed on tight muscles without sternocleidomastoid muscle nodules.
Stretching and strengthening exercises can be carried out through holding, carrying, and playing with the baby in postures and positions selected to achieve the desired active and passive movements. Strengthening overstretched muscles on the side opposite to the torticollis could be accomplished through postural reactions as the infant matures and gains better control of the head and trunk. Torticollis influences acquisition of motor skills. Restrictions and imbalances in the cervical muscles can lead to asymmetry of motor development. Since the introduction of the “back to sleep” program, there has been an increase in the incidence of delayed gross motor development. Torticollis can augment the impact of supine sleeping on motor development by further diminishing head control in antigravity positions leading to decreased weight bearing on the arms or by causing uneven weight shifts through the trunk. Trunk shortening on the torticollis side and asymmetrical transitional movements into sitting and standing are common. The adaptive compensations of the musculoskeletal system in the trunk and upper extremities can contribute to abnormal movements and posture.
Massage of tight neck muscles and subcutaneous tissues is commonly used in the management of infants with congenital muscular torticollis to aid in increasing pain free range of motion. Joint mobilization, myofascial release, and craniosacral therapies are emerging areas of practice in infants with torticollis. Therapeutic taping is sometimes used to support weak and overstretched muscles.
Guidelines for discharge from physical therapy and for monitoring after discharge are not well defined. Torticollis posture could reappear during periods of growth. The sternocleidomastoid muscle on the involved side may not grow at the same rate as on the uninvolved side, creating a risk of return of contracture. During periods of illness, teething, and acquisition of new motor functions, regression to the torticollis posture could occur.
Many infants with torticollis have coexisting deformational plagiocephaly severe enough to warrant use of a cranial remolding orthosis. The duration of treatment with a cranial remolding orthosis could be longer for children with torticollis and plagiocephaly who have residual limitations in cervical range of motion.
Cervical orthoses have been used as treatment adjuncts for those children whose lateral head tilt does not resolve with exercises. The most commonly used collar in children with torticollis is the Tot Collar. The Tot collar is adjusted to support the neck on the impaired side in the neutral position. The Tot collar is worn only during waking hours and is not used for children younger than 4 months of age.
Contemporary management of infants and children with congenital muscular torticollis must address the needs of a changing population. Since the introduction of the “back to sleep” program, there has been an increase in the incidence of infants with plagiocephaly with and without torticollis. Early detection and initiation of physical therapy is related to improved outcomes and less need for surgical lengthening of the sternocleidomastoid muscle. Repositioning is a required element of early management of both torticollis and plagiocephaly. Cranial remolding orthoses and cervical collars could be necessary as adjuncts to treatment. Active and passive cervical and trunk range of motion are an effective treatment for children with torticollis.