Congenital Torticollis

Etiology

Several theories exist regarding the etiology of congenital torticollis, including ischemia, trauma during childbirth, and intrauterine malposition (pelvic position).[10] However, none of these theories have been proven, and the exact cause remains unknown.

The leading cause is believed to be intrauterine deformation, which often occurs in situations associated with limited intrauterine space, such as in first pregnancies, decreased amniotic fluid volume, or uterine compression syndrome. Other causes of congenital torticollis include positional deformation, vertebral anomalies, unilateral atlantooccipital fusion, Klippel-Feil syndrome, unilateral absence of sternocleidomastoid muscle, and pterygium colli.[11] The most common form of torticollis in childhood is congenital muscular torticollis, characterized by sternocleidomastoid muscle abnormalities.

The neck muscles comprise a complex system, distinguished into 2 levels: a superficial level consisting of long neck muscles and a deep level consisting of paravertebral muscles. Among these, the sternocleidomastoid muscle is the most targeted superficial muscle in the anterior region of the neck, forming a visible and palpable mass. Its insertions on the sternum (sternum furcula), clavicle (two-thirds medial), occipital region (two-thirds side of the neckline), and mastoid apophysis, with its fibers oriented obliquely upward and outward direction. This muscle facilitates contralateral rotation, ipsilateral inclination, and flexion of the head, resulting in the head and neck tilting towards the side of the active muscle and rotation of the head to the opposite side.

Congenital torticollis is commonly diagnosed during the neonatal period or infancy.[8] In a prospective cohort study involving 155 infants under 12 months with congenital muscular torticollis, it was found that 30% of patients had gastroesophageal reflux disease (GERD). However, there were no differences in the demographic or clinical characteristics between torticollis patients with and without GERD.[12]

Epidemiology

The global incidence of congenital torticollis ranges between 0.3% and 1.9%, with some studies indicating a ratio of 1 in 250 newborns, ranking it as the third most common congenital orthopedic anomaly. There is a preponderance in males and among first pregnancies.[3][4]

The incidence of congenital torticollis has been reported to be 2% in traumatic deliveries and 0.3% in nontraumatic deliveries.[13] Additional data indicate an incidence of 53% in children born to primiparous mothers, particularly those with a history of traumatic childbirth. Typically, congenital torticollis is identified in neonates around 2 to 3 weeks of age and can persist until 1 year. It commonly manifests unilaterally but rarely can be bilateral. There may be a visible, palpable swelling known as a sternomastoid tumor in up to 50% of cases.[14]

Congenital muscular torticollis is categorized into 3 types:

• Postural (20%): The infant exhibits a postural preference without muscle tightness or restriction to the passive range of motion. 

• Muscular (30%): Characterized by tightness of the sternocleidomastoid muscle and limitation of passive range of motion.

• Sternocleidomastoid mass (50%): Presents with thickening of the sternocleidomastoid muscle and restricted passive range of motion.

There is a noted correlation between congenital muscular torticollis and developmental dysplasia of the hip. Therefore, in infants diagnosed with congenital muscular torticollis, conducting physical examinations and imaging to screen for and identify developmental dysplasia of the hip can result in early diagnosis and treatment, increasing the likelihood of successful nonoperative management.[15] However, congenital muscular torticollis has not been recognized as a risk factor when treatment for developmental dysplasia of the hip fails. 

Pathophysiology

In congenital muscular torticollis, where a palpable mass is present in the sternocleidomastoid muscle, it primarily consists of fibrous tissue. This mass usually disappears during infancy, being replaced by a fibrous band. Muscle biopsies and MRI studies of the mass have suggested the presence of muscle injury, likely resulting from compression and stretching of the muscle. 

Venous neck compression during childbirth could have contributed to decreased blood supply and subsequent compartment syndrome. Histological studies of material collected at delivery revealed edema, muscle fiber degeneration, and fibrosis, supporting the presence of compartment syndrome.[3][11]

In a retrospective study involving 2599 children diagnosed with congenital muscular torticollis, ultrasound examination of the sternocleidomastoid muscle identified 3 types: local mass, uniform thickening, and atrophy. Among these, children with the local mass type of congenital muscular torticollis demonstrated high success rates with nonoperative management.[16]

A retrospective study examining the sternocleidomastoid muscle, upper trapezial muscle, and cross-sectional area of the accessory nerve identified thicker structures in patients with congenital muscular torticollis. The study postulated that the size of the sternocleidomastoid muscle might influence the thickness of the upper trapezius muscle via the accessory nerve in congenital muscular torticollis patients.[17]

Histopathology

The basic tissue abnormality observed in congenital torticollis is endomysial fibrosis, characterized by collagen deposition and the accumulation of fibroblasts around the muscle fibers, resulting in muscle atrophy.[14][18] In addition, this fibrotic process can lead to decreased flexibility and range of motion in affected muscles, contributing to the characteristic symptoms of torticollis.

Gross examination reveals no hemorrhages or necrosis. Microscopic examination reveals a diffuse proliferation of uniform fibroblasts and myofibroblasts, degenerative skeletal muscle fiber, and scar-like collagen. Biopsied tissue stains positive for vimentin and actin. Pathological study with hematoxylin and eosin staining shows apparent interstitial fibrosis around residual myofibers in the lesion specimens.[19]

History and Physical

Parents often notice the infant's tilted head and raise concerns. The evaluation of a newborn with congenital torticollis should include a comprehensive clinical history, including any history of oligohydramnios, traumatic delivery, or pelvic presentation, and a thorough physical examination, paying particular attention to palpation of the sternocleidomastoid muscle. Clinical signs of congenital torticollis include:

• Fibrosis or shortening of the sternocleidomastoid muscle.

• A lateral tilt of the head in the frontal plane and contralateral rotation in the transverse plane with notable limitation of the active and passive cervical range of motion and a fixed postural stiff neck resulting from a restricted or fixed muscle.

• A painless palpable mass or tumor over the side of the neck along the sternocleidomastoid muscle; these are evident in neonates aged 2 to 3 weeks. The swelling is firm, movable under the skin, and soft. If the mass is small or missed in the neonatal period, the infant's head is usually tilted and flexed to the side of the lesion. Diagnostic confirmation is found in 50% of cases within 2 months. The nodule may grow for 2 months until it reaches the approximate size of an almond before it begins to regress; it may disappear entirely until the eighth month of life.[20]

• Modification of cranial morphology (related to the presence of plagiocephaly) by flattening the parieto-occipital zone and anteriorization of the contralateral ear to the affected sternocleidomastoid muscle with frontal flattening homolateral to the affected sternocleidomastoid muscle.[5]

• Compensatory postures of the cervical, thoracic, trunk, extremities, shoulder elevation, or trunk inclination to the affected side.

Due to unilateral muscle shortening, children with congenital torticollis often prefer to sleep in the prone position, with the affected side down. This position can exert asymmetrical pressure on the skull and developing facial bones. The constant pressure on the head can lead to remodeling of the cheekbones and result in facial hemihypoplasia or plagiocephaly. These changes affect proper breastfeeding positioning, making it difficult for the baby to suckle during breastfeeding. Throughout the child's motor development, language, and balance in different positions, such as sitting and crawling, compensations from disparate systems may occur, potentially resulting in consequences on orthostatic postures, such as scoliosis.[21]

In older children, the sternocleidomastoid muscle often appears thickened and condensed along its length, resulting in restricted rotation and lateral neck flexion towards the unaffected side (see Image. Child with Torticollis). These rotational changes can lead to flattening of the head, known as positional plagiocephaly. This condition may correlate with other musculoskeletal abnormalities, such as positional musculoskeletal deformities, including metatarsus adductus, calcaneovalgus feet, developmental dysplasia of the hip, and brachial plexus palsy.[2]

Evaluation

Physical examination is the easiest and most effective means of diagnosing congenital torticollis. Assessment methods include evaluating the passive cervical range of motion using an arthrodial goniometer, often performed by physical therapists. Additionally, assessing an active range of motion, if possible, and conducting a global assessment is essential.

Neurological and auditory assessments are fundamental to exclude other potential differential diagnoses. It is crucial to evaluate visual function, including eye alignment, the presence of red reflex, and pupillary reaction to light, to determine whether the eyes fixate and follow objects. Weakness in oculomotor muscles, such as the lateral rectus or superior oblique, may suggest that the torticollis results from a compensatory mechanism to improve vision.

During physical examination, if no muscle contracture is evident and joint amplitudes remain intact, this suspicion warrants referral to ophthalmology.[22] A collaborative approach involving ophthalmologists and other relevant specialists can ensure comprehensive care and optimal outcomes for patients with suspected visual involvement in congenital torticollis.

The incidence of hip dysplasias in patients with congenital torticollis is approximately 15%; however, other studies report that 1 in 5 babies with congenital torticollis has associated hip dysplasias. Regular hip examination and ultrasound scan by 4 to 6 weeks of age or a plain radiograph of the hips at 4 to 6 months are recommended.[2] Several risk factors correlate with a higher incidence of hip dysplasia, including female sex, first childbirth, family history of hip dysplasia, presence of other deformities such as congenital torticollis, birth with a pelvic presentation, cesarean delivery, and large fetus. While hip dysplasia can be bilateral, it is most often unilateral.

Early diagnosis of hip dysplasia is crucial as it is typically asymptomatic in newborns, and early detection allows for effective treatment, thereby improving prognosis. Late diagnosis can result in sequelae such as lameness, chronic pain, degenerative arthritis, and mental impairment. Thus, appropriate screening for this condition is essential, focusing on clinical signs indicative of hip dysplasia and the need for early diagnosis. When in doubt, referral to a specialist is recommended.

The clinical diagnosis of hip dysplasia systematically relies on major and minor clinical signs. Major signs are the Ortolani/Barlow sign and hip abduction limitation, while minor signs encompass the Galeazzi sign and asymmetry of the folds (inguinal and thighs).[23]

The evaluation of congenital torticollis plays a crucial role in treatment planning.[2][24] Diagnosis is primarily clinical, with only a few cases requiring complementary diagnostic tests. Typically, diagnosis occurs 2 months of age in 50% of cases, often identified by parents and sometimes correlated with plagiocephaly. 

Ultrasonography is the most common imaging modality, especially in the neonatal period. Magnetic resonance imaging (MRI) can be helpful to rule out nonmuscular causes of torticollis. Ultrasound is advantageous for assessing a neck mass, such as a pseudotumor, and long-term monitoring and posttreatment evaluation.

The tumor on the affected side of the neck along the sternocleidomastoid muscle usually resolves between 4 and 8 months of age.[2][25][26] Histopathologic studies are rarely necessary when imaging modalities regarding the etiology are inconclusive. Fine-needle aspiration cytology (FNAC) specimens are an option. Biopsy or surgical specimens yield fewer findings in the early course of the condition since they are obtained later in the disease course.

Treatment / Management

Treatment of congenital torticollis can be approached in several ways, with no standardized therapeutic approach. Professionals from various fields, including physiotherapy and osteopathy, may recommend techniques for treating torticollis in infants.[27]

With proper treatment, 90% to 95% of children show improvement before the first year of life, and 97% of patients improve if treatment begins before the first 6 months.[20][28][29] In cases of congenital torticollis, a palpable sternocleidomastoid mass is an important indicator for initiating intervention by the second month of life, as it influences the child's normal motor development.[10] The main objective is to attain an age-appropriate active and passive range of motion of the neck to prevent contractures and promote symmetry of the face, head, and neck.(B2)

Initial treatment focuses on passive range stretching and close follow-up. Parents are advised to incorporate positioning maneuvers into the infant's daily routine, such as during feeds, including chin rotation towards the affected shoulder. Infants can also benefit from supervised time spent on their stomachs when awake, facilitating motor skill development in the prone position.

Manual stretches involving flexion, extension, and lateral rotation should be performed at least 3 times a week, with each set comprising 15 stretches. Each stretch should be held for 1 second with a 10-second pause between each repetition. If the sternocleidomastoid muscle exhibits a fibrous aspect, stretching techniques are considered the most essential and evidence-based treatment.[2][7] (A1)

While numerous protocol studies in the literature demonstrate the effectiveness of physical therapy for congenital torticollis, there is limited reported data on the frequency and types of exercise. In many studies, the initial frequency of therapy sessions ranged from 2 times per week in the 1st month, progressing to once per week; some authors advocate for an initial frequency of 3 times a week. The duration of physiotherapy treatment for congenital torticollis varies depending on the timing of rehabilitation initiation, with studies indicating that earlier intervention leads to quicker establishment of normal cervical biomechanics and better outcomes. Published studies predominantly focus on stretching, muscle energy techniques, and other exercises promoting motor development.[30](B3)

The Tubular Orthosis for Torticollis (TOT) collar is recommended for children over 4 months of age. It supports the impaired side of the neck in a neutral position and can be worn during the daytime while the child is awake.[31] (B3)

Physical therapy may not always yield effective results for treatment, prompting the exploration of alternative interventions. One such approach involves the adjunctive use of botulinum toxin injections in the sternocleidomastoid muscle and other affected muscles in the region.[32] Surgery may be considered a last resort in more severe cases where conservative measures fail. However, physical therapy remains integral at all stages of treatment and follow-up. A retrospective study has reported that botulinum toxin type A is a safe and effective treatment option for refractory cases of congenital torticollis.[33]

Surgical intervention may be indicated in cases where there is no improvement after 6 months of manual stretching, if there are more than 15°in passive rotation and lateral bending, or if a tight muscular band is present in the sternocleidomastoid muscle. Surgical procedures may include unipolar or bipolar sternocleidomastoid muscle lengthening, "Z" lengthening, or radical resection of the sternocleidomastoid muscle.[34][35] (A1)

Surgical management has yielded positive outcomes in patients with long-standing untreated torticollis, including correction of head position and improvement in cervical range of motion. However, facial asymmetry typically does not get corrected through surgical intervention.[36] Additionally, a prospective study has reported significant improvements in health-related quality of life and clinical outcomes after surgical treatment of congenital torticollis.[37](B2)

Differential Diagnosis

Differential diagnosis is essential to rule out other pathologies. Some of the potential differential diagnoses for congenital torticollis include: 

• Vertebral anomalies like hemivertebrae and Klippel-Feil Syndrome
• Unilateral congenital absence of the sternocleidomastoid muscle
• Congenital scoliosis
• Ocular torticollis
• Sandifer syndrome
• Arnold Chiari malformation
• Neurological diseases
• Visual disturbances
• Syringomyelia
• Cervical spine tumor
• Brain tumor [8][26]

Prognosis

Most cases of congenital torticollis are benign and resolve spontaneously or with manual stretching. With proper treatment, 90% to 95% of children improve before the first year of life, and 97% of patients improve if treatment starts before the first 6 months. Craniofacial asymmetry also improves, especially in cases treated early. When the patients present late or when physical therapy fails to yield results, surgical management may be necessary. The results of surgical treatment are generally positive, with improvement in neck range of motion and correction of deformity.[8]

Complications

Delayed or unavailable treatment for congenital torticollis can lead to permanent anatomic abnormalities, including disfigurement, cosmetic concerns, and functional impairment. Craniofacial asymmetry may develop as a long-term complication if the contracted sternocleidomastoid muscle is not released. Therefore, it is imperative to correct torticollis promptly to prevent the progression of facial asymmetry and mitigate potential long-term consequences.[22]

Positional plagiocephaly is commonly associated with muscular torticollis, underscoring the importance of distinguishing this benign condition and craniosynostosis. A careful examination of the sutures, along with imaging such as a radiograph or ultrasound, may be necessary for accurate differentiation.

Management of plagiocephaly involves advising parents to implement frequent positional changes to halt the skull remodeling. Referral to physical therapy to improve neck motion is paramount for comprehensive management.